I wanted a Single PowerChair that goes INDOOR & OUTDOOR in Comfort, Properly! MK2 Version
Snow & Mud, on the Beach, in the Woods, Shopping Centres, Pubs, Vans, Houses & Tables are all no problem. It’s a very small Powerchair and is POWERFUL & compact with a low seat. Has speed, torque, range & unsurpassed Indoor capability as well as TRUE Outdoor abilities. No other Powerchair has this combined dual personality.
All FULL TIME ACTIVE Power wheelchair users actually “need” all terrain wheelchairs all day long! See why here!
This ultimate every day Do Everything Powerchair started out life as an old Sunrise Medical F55s donor Powerchair. But is now extremely modified and re-manufactured with just the main frame rail & a few seat components remaining as Sunrise originally intended.
All the rest is either hand fabricated by me or very modified or replaced with other better parts.
To see how and why it is truly better & what’s REALLY involved, please see and read the previous 2 pages. And also the earlier MK1 version – the “slightly” modified powerchair as this version is just an evolution of that one.
Ultimate do all power wheelchair!
This Powerchair makes pages like this one and Powerchair Manufacturers generally look ridiculous!
Total Cost: Just £1700 or $2500 + some effort!
Even with its tight class leading narrow width measurements it still uses Full Sized Group 24 batteries or my preferred 68ah AGM Odyssey batteries for safe 1 hour charging and full all day range.
And a very radically Re-Programmed 100 amp per channel controller, very powerful low impedance 4 pole 6,2mph motors.
To be swapped for an even better Dynamic DX2 system very soon. TOP END Control System (Interesting Reading!)
The X5 Powerchair for example is its only serious competition, (but its way too big indoors) I tested an X5 (Frontier) powerchair and It felt huge, high and gutless and didn’t fit my house or my van without a desperate fight. Too high and wide too long…
My chair a narrow 25,25 inches wide (640mm) as shown with its off road all terrain tyres and full sized batteries AND including its18 inch wide cushion (and that’s pretty narrow!)
40 inches short (1000mm) including anti tips and a very generous 10 inch deep centrally located footplate, A very compact and manoeuvrable chair indoors with “rounded corners” (no swing away footrests and no rear casters swinging about in the way) And its got 4 inches ground clearance and 16 to 18 inch seat height (adjustable).
It’s more compact & manoeuvrable than almost all “indoor only” small powerchairs! See here
18 inch (or less if wanted) seat height, A very powerful (masses of torque) and reliable Powerchair. With no ugly great battery box sticking out of the back (looking like its taking a dump) like most commercial rear drive chairs. Aesthetics matter And that usual lump hanging out of the rear on most powerchairs also gets in your way indoors! So I don’t have one.
POWERCHAIRIt fits my van, my house, dining table easily and goes anywhere outdoors in snow or on the beach with ease with better ride comfort and better controllability than any other powerchair. For a variety of important reasons that we will see later on!
Shown here (above) with its “Dry Summer” Kevlar lined Puncture Proof Lawn (and road) Summer tyres. Good for grass, dry tracks, road and pavements and Off Road in the dry summer months. A VERY smooth ride with huge sidewalls and low pressure compared to any conventional skinny tyred powerchair. Much better than “suspension” at the low speeds we travel at. And they are puncture proof Kevlar Shielded! OK on carpets (if dry!) too.
Shown opposite with its “Off Road” or all terrain winter wheels & tyres (tires) fitted. Good in mud, snow, sand etc. But they wear out faster on dry roads and pavements. Also OK on carpets IF clean and dry… Both give a much smoother ride than normal “mobility sized” wheelchair tyres due to the huge sidewalls and low pressures and greater floatation. (Powerchair Bigger Take a better look here!)
Both the above tyre styles deform over objects and bumps easily due to huge sidewalls, very low pressures and great floatation (large footprint). No road vibration or muscle spasm problems any longer! Better for pressure sore prevention too (less jarring and less sheer forces). Powerchair suspension sucks, is heavy, and takes up valuable space. Fat soft balloon type tyres are a much better solution that actually works better even on nice “smooth” pavements and roads. Not just off road. But they do that too! If you tried this for yourself you would be amazed how smooth it feels compared to any conventional powerchair.
Some Fun! See Movies (Windows media files) Warning… Turn the sound down as the program I use to convert the .mov files from my camera to .wmv ones somehow doubles the volume and turns up the high frequencies! It really just sounds smooth and clicks like every other nice shiny new powerchair. In all these movies it is radio controlled and has no occupant in it. Although I will post some asap that have, since I have been using this one for months now!
This is using Radio Control The same home made radio link gadget (sat on the seat) that I use when moving any powerchairs about while working on them, cleaning or putting a spare one into my van etc. Extremely useful device. Should be available from the manufacturers as disabled people NEED these kind of assistive devices. I can get into my van while sat in one powerchair for example and then drive an empty powerchair in afterwards. So helpful, as it allows me more independence and means I don’t spend all day waiting for other people. People do look at it a bit strange though! How? Drive your Powerchair by Radio Control
Looks a bit odd with nobody on board and driving about! Scares the dog. Don’t worry the radio link is safe because it fails safely too. Any signal loss or any radio interference and it stops dead instantly. Wont go again until it sees the correct encoded radio signal. And its really easy to drive remotely. Anyway the story continues!
And using THIS Anderson Plug and Socket and a 30 amp fast charger (below) it can be charged up 90+ percent fully charged in around one hour ready for an evening out! Perfectly safely. See advantages of Fast Charging Your Powerchair. Nobody likes waiting. Certainly not overnight! And I have way less time to waste than most! How long do you have to wait for yours to charge??? In addition my batteries now last about twice as long as they did when I used to run them all day and charge overnight. Now they get topped up in the middle of the day or when I get chance while eating or checking mail..
Switch Mode 30 amp, 1 hour Fast Charger. Fully digitally controlled 4 stage safe fast charging. Designed for Good AGM batteries like the Optima, and Hawker Odyssey ones that I use. Full overnight charging is still required at least every second day or so (to equalise and “even up” all the cells) but opportunity charging during the day (say 5.00pm while you check your email) is both advantageous to the user since you get to go out again “topped up” and ready for anything and makes your batteries last longer due to a lower average depth of discharge.
No matter what some other ill informed so called “experts” may tell you. And charging the batteries at 30 amps (or much higher) is perfectly within these batteries specifications and capability. Many Gel batteries can be fast charged safely too according to their manufacturers but they may take 2 hours due to inferior higher internal resistance. I have forgotten more about batteries than most sop called “experts” ever knew. And contrary to popular “opinion” opportunistic charging extends battery life considerably provided they also get at least one complete overnight slow charge every day or second day.
There are thousands of “normal” indoor & outdoor top of range powerchairs by a large number of different manufacturers which are small enough to fit in both my van and in my house and allow “reasonable” (but nothing like good enough) outdoor performance. But no off road capability. And also they are available the other way around.
There is one that tries to do both like mine does and almost succeeds – the X5 over here but it has a few issues regarding width and seat height for me as well as weak arms and mid wheel drive etc and typical horrible build quality and finish…. Have you ever seen a mid drive dragster, off road car or bike, or race car? No because adding a bunch of casters to both ends is ungainly and doesn’t work well. And it offends my mechanical sensibilities as an engineer… Anyway its too big / high / wide for sensible indoor and in my van usage.
Don’t worry about black tyres marking your carpets (unless they are white/light possibly!). I have a fully carpeted house (although mostly darker colours) and in ten years have never left a visible mark that didn’t just vanish with a vacuum cleaner when dry. Unless the carpet or the tyres are wet or even slightly damp you wont leave a mark anyway. If I come in from the rain then I just go into the tiled kitchen for a few mins until they dry. They do leave scuff marks on door frames if you are drunk and hit them but that just wipes off. Life’s too short to worry about this.
As far as I know, there isn’t a single powerchair on the market that can do both indoor and outdoor plus have some real off road ability.
I have looked very hard over many years. It has to be as small as my manual wheelchair while being able to operate all day long both on and off road and fit into my van and house and under the dining table with ease…
And also have speed and all day range and be totally reliable and long lasting as well as well built and finished well. And not just turn to iron oxide with the first shower. A tall order? It shouldn’t be since I accomplished it easily enough as a disabled end user in my bedroom! The manufacturers are taking the piss…
What exactly are the manufacturer – the “experts” actually doing? Beats me… I cant buy a decent chair!
EVERY PART OF AN INCH COUNTS. So its GOT TO BE SMALL!
TRUE SMOOTH OUTDOOR CAPABILITY IS ALSO ESSENTIAL.
Plus I have a life so FAST CHARGING in under an hour (for a 90+ percent charge) or top up as needed was an essential requirement too. This powerchair does all of this stuff and much more.
When I go out in the evening its charged up and fresh again. Ready for whatever happens. No matter how far I travelled in the morning. And lowering the average battery discharge level at the same time extends the batteries useful service life.
Also important is controllability and good programming and power/range/manoeuvrability. This chair beats any other powerchair in all of these things that I have ever found and tested by absolutely miles. Partly due to C of G position and partly due to Low Level Programming that manufacturers “wouldn’t approve” of!
I just wanted, of course, what other busy & active Para/Quad/Other “full time” wheelchair users really needs! I want and in fact NEED “everything” in one single long lasting reliable chair! A well built and well designed Electric Power Wheelchair that does absolutely everything well (Swapping chairs for different terrain, indoors etc isn’t an option!)
I needed one that allows me to leave my computer desk or dining table and get straight into my van to drive it from the very same wheelchair to take the dog for a walk in the local woods. Off road or along the beach for example. And then to the Pub on the way home for a beer. Come winter, rain, snow or summer.
Amazingly after all these years No Such Commercial Powerchair Exists! If it did I would have bought one already. But why the hell not? Its what we all need! Manufacturers please note, I get dozens of mails every week from people wanting to buy one! But that’s YOUR job!
So for myself I had to build one (actually I have 3) as you can see here. There was simply NO CHOICE! And build quality is up to my usual total OCD* perfectionist level! Because I am a nut case perfectionist engineer and want it to look good and wash clean and still look just as good 5 years down the line! (*Obsessive Compulsive Disorder)
Its a shame you have to build your own though, but non of the “real manufacturers” seem to quite “get it”. God only knows why. It wasn’t even difficult to build. IN A BEDROOM WITH BASIC HAND TOOLS by a T4 paraplegic end user! If I was a manufacturer I would do massively better than this chair too!
Finish — As such all parts of this powerchair, old, new and freshly designed/fabricated – even brand new boxed parts – are first shot blasted and then powder coated PROPERLY with the toughest thickest mile deep rock hard show quality powder coating, to make damned sure they are going to wash clean AND STAY SHINY after a few salty winters. Even the bits you don’t see. In fact especially those bits! EVERY SINGLE LAST PART.
All bolts are replaced with hand polished greased stainless steel cap headed (Allen) bolt ones, We don’t like corrosion!
All bearings replaced with corrosion resistant stainless steel versions as used in the food industry in the interests of longevity. Ever had a front caster bearing die? Its very common. That’s because hair gets wound in and water and corrosion follows… No nasty cheap steel bearings or fasteners on any parts anywhere on this powerchair. Its either Stainless Steel or its HEAVILY Show Standard Powder Coated – properly. Even all of the new alloy fabricated parts and the brand new wheels were blasted and powder coated to show standard along with EVERY single tiny part… I am very obsessive!
As you can see I have a choice of Tubeless Tyres. Two different types. For good reason. Actually I have complete sets of wheels and tyres to choose from. I modified the wheel mounting system to take cheaper better Tubeless Wheels and Tyres in these bigger sizes. They are now dead simple to swap over in minutes. One single Allen key. And swap the wheel and tyre complete. And much cheaper and better than the inferior grey small sized tubed hard “disabled” tyres that “normal” powerchairs use. So I keep a “spare” wheel complete and ready to fit in my van just in case it is ever needed. Although its unlikely for a bunch of reasons – later!.
I use these big low pressure (4 to 7 psi max) fat soft balloon type tyres not because they look cool, (yes I know they do!) but because they “float” over soft ground like grass and mud/sand without sinking in. Or when on a beach they ride above the sand. And also because on our pavements and footpaths you get a super smooth ride that’s far better than any overweight suspension system that any current powerchair has. I mean VASTLY better.
Actually fitting them and keeping the powerchair down to a narrow 25.25 inches (640mm) wide was a major engineering job though! Much brain strain.. Although as an end user quite why I should have to do this myself completely beats me.
Front caster wheels are actually “mini bike” wheels because they are cheap, light STRONGER prettier 3 spoke design plus easy to get (eBay as usual). The bearings and spacers and axles are all new fabricated and stainless steel or Aluminium alloy. I don’t like the corrosion that you always will get with stock steel powerchairs axles/spacers. (and bearings too…) That’s just cheap!
The axle location is now directly into the modified caster fork leg which stops the things coming loose for a bunch of reasons instead of being located by the bolts as were the stock axles. Who designs these things? This is common practice on most powerchairs and then it needs “tab washers” to stop them coming loose as all the shock loads go through the thread! I fixed the problem rather than try to cure the symptoms… Looks prettier too and no rusty steel bolts..
I can for example run over the shaft of a big hammer laid on the floor in my workshop as I did today with these fat balloon off road style tyres and not really know it! You barely feel anything at all. due to their huge sidewalls and low pressures absorbing the hammers shaft. With either of these tyres the world feels smooth and shocks and vibration simply do not make it through to you! No suspension can do that at the slow speeds with small wheels that we have.
They just “deform” around the object (or curb / bump / rock etc).. Its the same in the street as bumps and shocks or rocks are not really felt at all. You ride and float on a cushion of low pressure air. The off road ones are “slightly” better at this “floatyness” than the lawn or road style one is, but both offer a really good ride compared to stock hard grey narrow high pressure wheelchair tyres, even with the so called suspension that some powerchairs use for marketing points!
Both big tyre types perform much better in this respect than any normal powerchair tyre/suspension can do. When will the manufacturers actually realise all this obvious and pretty basic stuff? Why do we still even have hard narrow tyres designed to damage your spine and help cause pressure sores? Why do OT’s and powerchair manufacturers not understand even this basic stuff? Designed by “teams” of people with lots of paper qualifications and no real engineering clue comes to mind. So instead of one guy with some natural understanding and drive and vision we get designed by committee!
I will only normally use tubeless tyres on any chair since they are massively less likely to suffer a puncture. No tube to “pop” like a balloon. Or stretch around the puncture hole stopping any sealer from fixing it or letting the air out.
And on my chairs tyres are always 1/4 filled (that’s a HUGE amount!) with off road puncture seal fluid… Just in case!
So why do most bought powerchairs have either puncture prone small hard tubed tyres or “solid/foam filled” tyres in the 21st century when much better alternatives are available??? Again it completely beats me. Its not like I can get out and walk home!
The Off Road style tyres look “cool” and are much better in winter on wet or muddy ground or snow and on sand (beach?) The road styled ones are actually grass/lawn tyre designed for lawnmowers etc, are better and harder wearing in summer and are Kevlar lined and almost completely puncture proof.. You have to choose! Both are way better than skinny mobility HARD SMALL grey tyres. Even less to worry about. Both have a high degree of comfort and “floatation”. See the previous pages for full details.
Even with those fatter grass / lawnmower tyres it still fits in my van as planned with 2 inches each side to spare. Its total width with these fitted is a narrow 26 inches dead. (25.25 inches with the other Off Road rubber below) Why does it matter? Because wider is useless indoors! Like most other top end powerchairs…
With the other off road 145/70-6 tyres fitted (below) its under 25.25 inches wide (640mm). That was why this project was a pain in the bum… Trying to keep to the 25.25 inch (640mm) total width with a foot (300mm) of rubber was not easy! It leaves just 16 inches to fit two very powerful 4 pole motors and the full sized group 24, 75 amp hour (ah) batteries in the middle. The manufacturers still don’t seem to have this figured out. See previous pages…
The “Off Road All Terrain Tyres” are 1 inch narrower still. So there in now about 3 inches or so to spare on the ramp with those quad bike All terrain tyres fitted. The total width is now just fractionally over 25 inches (640mm) that’s the same as most indoor only powerchairs and narrower than most full size top end Powerchairs like the Quantum Rehab R4400 etc. And this measurement INCLUDES an 18 inch cushion fitted —
Which means the arms are moved outwards to accommodate it.- the manufacturers do not include this as it makes their total measurement wider still… Makes you wonder what they are on! One day they will figure out that every inch or part of an inch really does matter. Until then I will build my own!
The hand “push grips” on the seat uprights “backrests” are shortened by some 4 inches too, as they are in the way normally and hit walls especially now the seat has been relocated rearwards to move the C of G back to allow some real control. manoeuvrability and wheelies etc. Now they are just long enough to hang your shopping on but don’t get in the way. It want practical to manually push it anyway so why impair its indoor capability because of them?
Every single part inch matters and they all add up to a very agile and small but extremely strong powerful powerchair that doesn’t look it! Very compact in every dimension but full all day power and range. Never buy a powerchair that has less than 70ah batteries/100 Amp controller. At least if you are a serious all day active user. If you are heavy (as I am), and expect some reasonable range or performance from a powerchair, then any less is not going to work… You cant beat simple physics no matter what the “specs” say.
Its also short enough to easily turn around inside here with masses of space to spare. total length is just 40 inches (1000mm) including a very “deep” full footplate and it has no “corners” (factory swing away footrests or rear castors swinging around behind you) making it extremely manoeuvrable in very tight spaces. Much more so than traditional mid drive indoor powerchairs that cannot turn around in my bathroom or hallway for example.
These are my winter tyres. 145/70 – 6 sized off road quad bike tyres. They are not puncture proof like the Kevlar lined lawn tyres so have a full litre of off road puncture seal liquid in each one! Off road sealer is way better than the usual road going tyre seal, for slow vehicles. Its thicker and more effective but causes balance problems in faster machinery like cars.
They are tubeless tyres and wheels although this one has a tube in it. That’s a bad thing and it will be removed as soon as I get chance. That’s Brian’s fault. He fitted the tube while I was looking elsewhere because he thought it needed one… You cant get the staff!
Because of the very low pressure a tube actually is not as puncture prone in these tyres as they are in a “normal” powerchair. As they (tyres) just deform around nails, glass etc anyway due to the huge area and low pressure. If they run over your fingers it does not hurt at all. Or the dogs tail. I manage that at least daily! He complains less with these on!
As I keep saying and trying to tell people EVERY INCH or tiny fraction of an inch matters. A lot!
As does its Programming … This chair is the ONLY chair I ever tested that has accurate powerful control – follow the link!
That’s why the rear anti tip wheels, swing away footrests, arms, arm tops and control pod mounting (not fitted yet) are all either removed, modified or shortened or cut off etc… There isn’t much left on this chair that isn’t modified or completely replaced or moved, one way or another apart from the main tubular frame. I ACTUALLY like that part! But even it could be improved on… I have a plan…
Even the anti tip wheels have been relocated 4 inches more inboard each side and are 2 inches shorter and an inch higher & use much smaller diameter prettier harder wearing wheels so as to make the chair as tight as humanly possible and as short as it can ever be. As they are more inboard too they don’t hit anything when manoeuvring indoors.
Every inch or two removed on arms, front end, etc all more than add up! They are actually 44mm diameter skateboard wheels shown with stainless steel bearings and spacers. (as used in all of this powerchair) to prevent any corrosion from ever happening. I build things to last. And the mountings and the alloy bar are HEAVILY powder coated. Quick wash and its as good as the day I built it. Salt doesn’t turn this chair to dust.
There are 4 wheels and a bar going across to make it harder for them to sink into soft ground when off road. This powerchair wheelies like a mad thing because of the power, the programming, and the C of G position and these allow it to tip back to some 40 degrees as they are higher up than stock too. Only the spirited user need apply. It can sit back stationary, on its anti tip wheels balanced in this position at will. Just use the joystick to reverse A LITTLE and stop quickly. It then sits parked up, but up ended while I drink beer…
This means that I can easily tip it back on to its rear anti tip wheels and sit for an hour at a time safely and chill out in the pub while drinking a beer. Relaxing and pressure relieving with a quick touch of the joy-stick. Much quicker than a slow tilt seat! Which I am about to add anyway… Now also done!
No single part of this powerchair is just built without some SERIOUS thought as to how the whole thing functions together.
No built by committee here! I leave that to the teams of “experts”. Even the anti tip system had much consideration. How can we get the manufacturers to do the same? Not everyone wants the same thing but they could add adjustability too much like sports manual wheelchairs..
All the bolts used (yes all) are polished stainless steel cap headed or domed Allen bolts and are greased on assembly. No rusty steel hex heads on this powerchair! Makes my blood boil! These things cost as much as a small car and they rust and corrode after one winter as supplied from new if you actually use them as intended.
Every single part (yes all of it!) seen or otherwise new, old, or hand made has been powder coated with thick mile deep gloss applied electro statically as a powder and cured in a kiln (oven) to prevent any future corrosion and so ALL PARTS will look this good after a few years road salt and abuse with just a quick wash! That’s how it SHOULD be. Not just the frame as on production power chairs.
I hate to see other peoples powerchairs looking so dull, deteriorated and corroded even after a single year. The paint on 90 percent of the parts on a new powerchair is unbelievably thin and dull and plain cheap and goes grey/matt.. A quick coat of thin black satin paint without primer is all most parts normally get. Even if powder coated from new the quality is dismal. Usually just the frame gets some decent paint. And they get away with this because nobody complains or seems to understand the difference. Its fast, cheap and looks good for a few months and in the showroom only. I don’t like it. So I do it properly to last.
Another rear view. The rear lights don’t actually work. They could but I cannot be bothered. There are no front lights either. I don’t need lights but this light cluster fills a gap without me having to fabricate anything!
It could work of course if I wanted. The stock front lights and associated bracketry all weighs a ton, gets in the way and hits things and is another dirt/rust trap. So another 12lb of wiring, lights etc in the bin!
And lights on the front serves no useful purpose unless you really want to get killed on the roads! I keep off them at night its just safer unless crossing the road. Other than its technically a “legal requirement” in this country to have lights on any powerchair that goes faster than 4mph If you do REALLY WANT lights then much smaller more efficient lighter LED lighting is available instead of the stuff stock heavy huge things steel and glass things all powerchairs seem to come with.
These rear ones are lightweight though. The lenses are epoxied in place now neatly. As stock they don’t even fit well and keep popping out! As usual I had to fix this.
A similar view with the other set of winter wheels and tyres fitted. These are about half the price of grey mobility “hard narrow” tyres. And come complete with wheels! So now dead easy to swap with just 1 Allen key. Especially useful if you get a puncture and have someone bring you a spare from your home or van.
Front — with a white reflector! My attempt at road safety! Note adjustable bars and rose joints. The lightest and prettiest and strongest way to make adjustable seat and footplate supports. Everything is lightweight alloy, powder coated and adjustable.
Rose Joints – About £1.70 each on eBay from Karting suppliers. I used 14 of them in total on this powerchair. They are strong, self aligning, do not rust as they are heavily plated and are adjustable for length. Also available in stainless steel.
The bars are powder coated alloy of course. Manufacturers manage to do this kind of stuff with lumps of iron that you cant lift so it can go all rusty! Footplate is 4mm alloy plate too. the whole front end is very light. Even the front wheels are lighter than stock and use stainless steel bearings and bolts, and alloy spacers etc.
Why not off road style front tyres? Well only a fool would do that!
See those floor tiles? They are 12 inches square (actually 300mm). The tyres overlap each side by around 1 inch (25.4mm). That’s just 26.00 inches with these tyres and just 25.25 inches (640mm) with the off road tyres fitted according to my very accurate ruler.
Same rose joints/rod ends as the front support the frame/motors/rear sub frame here on the rear etc. There are four bars to make sure the motors cannot “twist” as they do in a badly designed stock chair as the rear swinging arms bend under load. All rose joints are 8mm. All alloy bars are 16mm diameter. And powder coated of course! They are 12 inch tiles. That should make you see how narrow this fat tyred powerchair really is!
This older “stock” SLIGHTLY modded powerchair above is 25.5 inches wide. A quarter of an inch wider than the new fatter tyred version! And its heavier with its hard narrow (tubeless) tyres and suspension arms and shock absorbers etc, giving the typical powerchair very harsh ride outdoors with its useless suspension! Fat low pressure tyres are so MUCH better.
The abovee is my “standard” powerchair setup. This is here only so you can see the differences and that the width is still the same overall as the stock SUNRISE F55s Powerchair.
And so you can see what a pig of a job it is to fit everything in without making the powerchair wider than stock! Remember it still has the same sized batteries! Actually they are a touch bigger now! (AGM Group 24 Odyssey) I still have two of these narrow tyred powerchairs… This one is absolutely unused and was finished only 2 months ago as a “spare” just in case. Both will be modded to fit the motors/batteries/wheels/tyres to match the new one since its just as good indoors with “corners” a rearward C of G and very small measurements, just massively better at everything else outdoors!
Back to the new version! Old fully detailed build is here (six pages) But most or the rationale behind the new chair is on here, these pages only document the additional changes.
Side. Look at the shine on those powder coasted wheels! Standard powerchairs do not shine like this one. Every last bit of it. ALL parts. Salt in winter has no effect on this chair. There’s nothing to rust! And a quick rinse in my shower room sees it clean and shiny with ease! Photos do not do it justice somehow.
Kitchen. MMust push that arm in! And tighten it up… And fit the control pod on the inside of the arm to save another inch or so. Not quite finished yet.
The seat height is also pretty low. Here its tilted back. That lifts the front edge. Currently as seen its 18.25 inches. If the seat is levelled then its 2 inches or 50mm lower or a little more at the front. That’s much lower than many other power wheelchairs. Plus there is no reason that I couldn’t make it say 2 inches (50mm) lower still as there is nothing below the (modified) seat base.
And I made the seat mounting plate anyway so as to move the complete seat backwards by 3 inches or so to put the C of G in the correct place. I have a spare “ram” (actuator) somewhere. When I find it I will replace the adjustable bar with it and then the seat angle can be adjusted via the joystick like my other previous powerchair build here
The complete centre section is hand built so as to allow the batteries to be turned around long ways and the motors to be mounted inboard to make room for the big tyres…
The batteries are AGM Hawker Odyssey as they offer 20 percent less cycle life in return for being able to produce enough current to supply the 4 pole motors via the reprogrammed 100 amp x2 Penny and Giles control system. Gel batteries just cannot Its down to the difference in internal resistance.
BCI Battery Sizes, Group 22, 24, 34, 27 – battery sizes
But I really need Lithium Ion Batteries for Powerchairs and Scooters
Tried a set of MK Gel batteries (sent FOC by a dealer) and they were frankly crap! Even fully charged there is half the torque or wheelie capability. And they get worse throughout the day. Gels cant do big currents well.
This wouldn’t effect most Chairs and they are normally very good batteries but this one actually takes its 100 amps per channel much of the time due to programming and very low impedance motors. That why it can tow a car or pull up tree stumps! At least it can with the Hawker Odyssey or Optima batteries! Not with MK Gels. They (optima/hawker) may not give the cycle life 400 against 500 but they do give the power!
Battery internal resistance matters. As does battery cable resistance. Mine are shortened as much as possible and the loom simplified and shortened and uses just one plug and socket and sensible cable size. Every volt that you lose due to resistance under load (batteries, loom, or controller/motors) is power wasted. Under say full load gel batteries drop about 1/4 of their voltage when half discharged. Internal resistance increases as batteries become discharged…
Drive your powerchair by Radio Control (how its done page)
Ignore the strange thing on the seat. Its my home made Radio Control interface that allows me to drive all my different powerchairs around empty by radio control. It means I can work/clean one while being sat in another! It just plugs into the lead that would go to the normal control “pod” if I had one fitted yet! Its on my desk… Awaiting stainless steel bolts again.
Notice inboard motors, longitudinal batteries, and the new small single bit footrest plate and the adjusting rose jointed bars. All powder coated of course! And the seat frame has had the swing away footrest mounting points cut off…
The arms have had the stock big (sweat and pressure sore inducing) plastic sides removed. These things stop you getting to your pockets too, what were they on?
Also removed because they are an inch thick and heavy and look awful. That inch holds the arms and the arm tops an inch each side wider than is really needed! Since it hits the user first. (every inch matters and there’s another two!)
And then the arm tops are fitted in a way that wastes another inch each side as is the control pod… So another 3 (yes three!) inches saved there after correction… Do these guys ever actually test or try these things? That’s 5 INCHES TOTAL SAVED just by a little re engineering the arms alone! An 18 inch cushion and total width of 25.25 inches.
rear drive electric wheelchair
x5 PowerchairBattery Door can be released with one bolt (one Allen key) then the door hinges downwards. The batteries slide out on a rail or track. Easy to swap in a hurry. Much easier than a stock powerchair. And unlike many powerchairs off road or otherwise there is no great ugly battery box sticking out of the rear. That great lump hanging out behind most powerchairs is reason alone to stop me buying one. Looks terrible!
E.G. The “almost made it” Frontier X5 >>>
Its underpowered, slightly, just an inch or two too wide and the seat is too high, but the rear view and length is the real problem! That and I hate mid drive 6 wheel chairs with extra wheels sticking out all over to hinder your manoeuvrability… No T shirt!
Nothing looks worse than a powerchair with a huge battery box hanging out of its bum… Any normal 50 amp hour to 75 amp hour battery can be used here in my chair but its best to use quality AGM batteries if you intend to use the performance and to fast charge the powerchair in one hour.
Dunno why I put this pic here! But it shows how easily it goes in the van! And how accurate my Radio Controlled driving is! But we did that already! I give up and the pubs open… More soon.
The arms are not adjusted or tightened up here. So right one is sticking out too far and for a 20 inch cushion. left one properly fits my 18 inch Jay2 gel cushion.
Ever been drag racing? That’s where I have seen that look before…
I could easily fit a car type Recaro seat of course (I have several Recaro seats that I have removed) as they look sexy as fitted by many manufacturers for photos and brochures. But they move the C of G up and forwards and that means it works badly as a powerchair! So they can stay in the garage. To me function is way more important than a fancy car type seat!
Up the ramp and straight to the steering wheel where the powerchair gets automatically locked in place by a device on the floor. This simply clamps hold of a 16mm bolt. It releases electrically at the touch of a button.
Locked in place by the electronic wheelchair clamp and ready for me to drive away! Except I am sat in this other identical powerchair and driving that one via a radio control link and taking photos while drinking a cold beer…
So I cant drive away obviously. But at least I can check it fits the fie down as per the plan! My ruler said it should. But we need to test.
From the other side Don’t get confused by my left hand drive van! It misses everything neatly, and fits perfectly and is lined up centrally with the steering wheel. Perfect. Rulers work! 1 inch between this tyre and the vans door pillar. And there’s a good inch clearance to the side pillar where the door closes. And the chairs arm misses the door pocket by miles. So all is correct.
Reversed up to a wall to show how a good powerchair SHOULD look. This is important. If you reverse to a wall and your head doesn’t touch it first then the powerchair is in the way. Its too long at the rear making you as a vehicle longer than needed,
There is no way you can turn into a doorway or around in a loo or a corridor if the length exceeds the available space. Length matters way more than “turning radius” which makes little difference if the chairs too long! Manufacturers love quoting that. But its pretty meaningless.
So either modify it or sell it. I am serious! A powerchair that will be used indoors needs as much manoeuvrability and needs to be as small in overall dimensions as humanly possible. As I keep saying EVERY INCH COUNTS.
When I am seated I am a specific length. My head forms the rear limit and my toes form the other. That’s my seated length. Width is also important. Having the wheels in the middle, the rear, or the front doesn’t make any real difference. Length is much more important. As is diagonal width (corners formed by rear castors or front swing away footrests etc) when you need to turn in a tight space.
Every effort possible went into making both width and length and diagonal “corners” as small as humanly possible in my heavily redesigned powerchair. Its now less than almost every other chair regardless of “size” or manufacturer.
The “corners” matter most because they hit door frames etc while trying to turn into a doorway where space is limited. For this reason I hate mid drive or front drive powerchairs as they have casters swinging about being you forming big corners! And they are generally in the way when you reverse to a wall so the whole chair is longer than needed. Or swing away footrests at the front…. Just as bad.
One picture I had left…
The seat is relocated rearwards by around 3 inches or so compared to a stock F55s (adjustable on mine), and the wheelbase shortened compared to the stock powerchair by moving the rear motors forwards an extra inch. Because… Amongst other things…
It now wheelies like a mad thing. Which is great! Even when already moving at say half maximum speed it wheelies at will. It means getting up a curb is a matter of a quick “wheelie” by accelerating harder (push joystick) and let the big soft rear tyres take the “bump” out of the ride up the curb, as they deform around it.
Leaving a curb is the same, quick accelerate off the edge and a small wheelie and land smoothly on the big soggy balloon 5 psi rear tyres only. Just as people in manual wheelchairs have been doing for decades only smoother.
Most stock rear drive powerchairs are very nose heavy so this kind of stuff (or any semblance of actual control) isn’t possible and you would land bad or break something. The only disadvantage is that I “could” tip myself out of the rear in extreme situations. And I have done several times. But that too is no different to any sporty “tippy” manual wheelchair. Its down to user control and how far you wish to push your luck!
At least in my chair I get to chose rather than the safety Nazi manufacturers telling me I cant.. Anti tip wheels stop that ever happening on hard surfaces, but it is possible on the beach! Or steep ramp. (Ask me how I know!) So if I come across any really steep bits (so steep most wont attempt it) I just reverse up. The limit then is me sliding out of the seat… A lap belt helps. Its got lots of power so the limit here is you!
The rearward C of G means full control in the same way as a manual sports wheelchair. As any uneven surface just means a front caster leaves the ground rather than a rear wheel so full control is maintained. E.G. I can let a front wheel go over the edge of a curb or ramp and the chair just sits on three wheels. So tree roots, off road stuff is all dead easy and fully controllable. That’s NOT the case in 99 percent of rear drive powerchairs as they are all front heavy.
Rearward C of G means that a puncture in a front caster wheel can be ignored for days. I can actually take a front wheel off and still go to the pub. Yes I did that with the last powerchair
Rearward C of G saves battery power, range, and average depth of discharge too! Turning on carpet, grass and to a lesser extent on smooth outdoor surfaces takes many more amps than driving along even flat out. Up to and including the maximum amps your controller allows.
If there is lots of weight over the front of your powerchair then this gets worse. As the C of G is moved rearwards the effort and energy expended to turn (amps) gets less. In addition when driving in a straight line on a less than level surface (left to right say, like the camber of the road edge) the front of your powerchair tries to head for the kerb.
So to go in a straight line one motor must pull and the other must push twice as hard fighting it as well as pushing you along!! So moving the C of G back also reduces this huge power sapping loss too. Of course mid drive chairs do this already. But they have too many legs and sticky out bits for my liking!
Bedroom built F55s/Off Road, Indoor, One Off Special do all powerchair Specs…
Total length not including footplate 30 inches (750mm). for transport. Seat back removable too with thumbwheels.
Total length including footplate:
40 inches (1000mm) at the moment which is already about as short as you will find for a full power top end powerchair.
If I cheated and used a narrow footplate like on the X5 or on most manual wheelchairs or swing away footplates then about 6 inches or so less! Bt the reality is that your feet stick out anyway so what’s the point?
But it also has no corners as the single plate is in the centre only helping manoeuvrability further still. No wide cumbersome swing away footplates stuck out in the corners. And no casters swinging around at the rear. If I modify the frame or make my own as I have considered then the front casters can come back a few inches further and the foot plate can follow. So it could be even shorter. Say 35 inches total. Or less than 30 with a shorter footplate!
Width at widest point (rear tyres)
25.25 inches (640mm) It depends on tyre pressures! And tyre manufacturer. They vary a fraction. That’s as narrow as almost all indoor powerchairs and narrower than most.. They vary from 23 to 27 inches generally and my measurement is s with an 18 inch cushion! Manufacturers use small cushions when quoting width to cheat as the arms have to be adjusted outwards further than mine do.
Tilted back by 12 degrees 18.25 inches That’s pretty low for a powerchair. At the front If levelled it can be as low as 16.25 inches. You have to add a cushion typically 2 inches to that in use. It could be made an inch and a half lower than that without hitting anything if required or as high as you wanted. It just involves a pair of new fabricated seat brackets but there is plenty of space to do so. So you can choose!
Unknown will update but its Lots lighter than stock F55s was judging by the pile of rust prone iron I cant lift in the corner of my workshop. Includes a multitude of steel tubes and brackets, the swing away footplates and lights, as well as the heavy rear swinging arm and suspension components, fake carbon fibre bodywork, original heavy wheels, “sides” that were on the arms and loads more.
Depends on user! 4 inch is easy enough even in this chair. But it hurts… Bigger maybe possible with the new one since its soft fat tyres deform around objects like curbs and they feel “smoother” Dunno depends how brave you are… Get it right and 4 inches is easy. Get it wrong and tip out the back! Done that too. Doesn’t hurt as long as you hold your head forwards! But you cant get back up without help!
Going down 4 inch curbs is easy with a quick wheelie and quite smooth.
Max user weight:
Unknown, I am about 20 stone see notes about range. 25 stone or more wouldn’t hurt it physically but batteries / range would suffer… There can never be a real “range” figure on any powerchair. Too many variables involved making such claims meaningless. Weight figures are meaningless.
More than 15 degrees. Probably 18 is safe if you can lean forwards.. Unknown max depends on user weight and seating position. Power isn’t an issue here no matter how steep.
If you can stay in the seat it would reverse up very steep slopes. More but requires user skill and control like a manual wheelchair going forwards. Safe in reverse on VERY steep ramps if you don’t fall out of the front! But tips back going forwards if its too steep. Requires some user skills like a sport manual chair… Not for old ladies. It has the power for steep angles even with my considerable weight in it. If not the stability! If you want manoeuvrability, and a machine that wheelies easily then it tips back easily. Its a user adjustment choice much like a manual wheelchair.
See this page! Length is all that matters. (!) This chair is very manoeuvrable and is short and has no corners to hit door frames etc when turning
100 amp (2x 100) Penny and Giles Pilot Plus (reprogrammed severely to allow actual regular access to that 100 amps per channel.) The batteries do not like it however. Soon to be up rated to R-Net with more amps still! My clamp meter shows the chair draws 100 very often so a bigger amp controller is ordered. See TOP END Control Systems
Electromagnetic release like almost all powerchairs. But its turned off and manually adjusted to hold the brakes “off” at all times as I hate the clicking. It rolls down slopes like this but its lovely and quiet. I can switch it on and off at will.
145-70/6 Low Pressure (4 to 7 psi) Tubeless for less punctures! And 1/4 filled with tyre seal fluid just in case. Or 15 x 6.00 – 6 “puncture resistant Kevlar lined Lawn” tyres. See pictures above…
6.25 mph Depends on terrain, user weight etc for exact speed. About 8mph down the hill that is my street! It is very easy to arrange for faster speed like 8mph but that costs range, torque and ability. Batteries are not yet capable of this unless you are light. In ANY powerchair. Physics wont allow it.
25 miles. Depends entirely on terrain, type of use, weight of user, temperature etc, See range I do about 10 off road dog walking and it needs a 1 hour fast charge before the pub… Range is meaningless.
4 Pole 6.2mph EMD about 2400 watts limit due to 2x 100 amp controller limit. They take 100 amps plus upwards if its available to about 1/3rd max speed given a chance (if programming delays and motor settings allow) as they are pretty low impedance motors. So that at low speed that is 2400 watts according to Mr Ohms law. But that’s not how motors are rated. So I Dunno! They are more powerful than all other 4 pole motors I have experimented with.
Group 24 or 34 – 55 to 75 amp deep cycle. Hawker Odyssey AGM batteries fitted as Gel batteries are too high internal resistance and cannot cope with discharge currents required + Fast charging from about 60 percent used up to 95 percent full in under 1 hour. BCI Battery Sizes, Group 24 & 34
Motor and controller power:
Voltage (E) = Current (I) * Resistance (R)
Power (watts) = Current Squared (I^2) * Resistance (R)
Power = I*E = E^2 / R
2400 Watts in stalled and low speed (low rpm) power. As measured with a digital Clamp Meter in actual use. Rated is 900 watts each I think…
Approx 100 Amps 24 Volts (nominal) on each motor cable and using ohms law. 100 amps x 24 volts = 2400 watts while accelerating or stalled on each motor. And a motor impedance of 1.2ohms.
I have no idea what the “rated” wattage is although 1800 watts total rings a bell. 900 per motor? But that’s not what I measured. In any case I have about a dozen different 4 pole motors here and these are by far the most powerful. Of course the motors are not 100 percent efficient so you only see around 80 percent of this measured power consumption at the wheel… But it can still pull up tree stumps.
That’s a large current. Hence the use of Optima or Hawker Odyssey AGM batteries rather than Gels which cannot properly cope with a 100 amp load without large voltage drops and eventual damage. (or continual fast charging!)
It will be getting a 120 amp per motor R-NET control system shortly or Dynamic DX2 and then the low impedance motors will be giving an additional 20 percent more low speed torque! Or better. This MAY eventually demagnetise the motors. But hey its worth it! It can pull a car and accelerate hard with 6mph gearing already which is ideal for off road use…
Why I need it!
One day the manufactures will understand this concept. Until then I have no choice but to build my own powerchairs or I would have to suffer like most other disabled people do. Don’t want to be one of the “masses”? Then get your hacksaw out! It wont make itself! If you are a manufacturer and need some help call me, I am available. But I don’t do committees or compromises so if you work like that then forget it! That’s why all the current top end powerchairs are frankly rubbish!
That’s the main two reasons for needing a truly capable powerchair above. They don’t seem to notice I have a wheelchair. Its having the ability to get on with your life. Bought powerchairs do not allow me this freedom. Non of them. A powerchair should not be in your way as all the alternative ones, that I can actually buy, so obviously are! So if you cant buy a solution then you just have to build your own!
I need to get out of my house and into my van, to walk the dog (here for example or the beach) daily. My powerchair has to be good at everything all year round. Nothing else will do. That’s why I build my own. Its not always dry and sunny down here! And it snows too! It has to get under computer desks, dinning tables, into any pub/bar/restaurant, into my van where I use it to drive from and be able to easily traverse tracks like the one above in the muddy depths of winter etc. All in one powerchair as I cant keep swapping or moving several about. Why cant I buy one?
There is no powerchair available that can do all the things that I (and a great many other disabled people) need to do. It also needed to be supremely manoeuvrable and narrow/short with no corners or castors sticking out the rear. Indoors it HAS to be as compact and manoeuvrable as no other indoor/outdoor powerchair. Outdoors it has to have range, power, and a smooth capable ride. And be fast chargeable from home or vehicle.
If all this stuff is so easy and obvious to me as a disabled end user and I can do it in my own bedroom myself. Then why isn’t it so obvious to the manufacturers with all their fancy workshops and big budgets and manpower? It totally beats me. They just seem incapable.
See how “Small and Manoeuvrable” is essential even outdoors! And see how even a modern City like New York is still an off road expedition! Control (programming and C of G) as well as total width and length and ability to manoeuvre very quickly and accurately matters lots even when OUTDOORS in a big modern wheelchair friendly city.
Think how much difference this ability makes when indoors in your house, van or in a busy restaurant. Or in small less wheelchair friendly towns and undeveloped rural villages! Also watch how much the camera mounted on this guys wheelchair shakes rattles and rolls as he goes over these modern smooth city streets. That causes pressure sore issues, discomfort, spasm problems and is plain uncomfortable!
Then you may understand why big “off road” low pressure balloon style shock absorbing tyres are ESSENTIAL equipment! And see “why all powerchairs need some off road capability”. And understand why as I keep saying every inch matters!
The thing is ALL OF THESE THINGS can be in one small agile powerchair. My own home built chair fits the bill. NO manufacturer makes a powerchair that does. Why is that? Beats me…
This video below is not mine I hasten to add, its simply an example of a typical modern city and its problems…
This is my old and almost stock F55s powerchair after relocating the seat rearwards a few inches and re-programming it to get some proper instant control…
You can balance it like this or drive around while tipped back if you practice just like a manual wheelchair should you wish >>>
It wheelies OK, and at will, just by accelerating forwards but my latest completely re-designed powerchair above on this page is much better at everything.