PINNED - Where to find everything powerchair related

[Josh]

I'm looking for a cheap place to find used seat mount parts for a jazzy 614.
I found this place which is significantly cheaper than Southwest: http://stores.ebay.com/electric-wheelch ... ter-parts/
any others?
Also, where might be a cheap place to buy batteries if the need ever arises?

Does anyone know if other chairs have the same seat mount parts as the 614? if so, I know a few people in my area who have random selections of donated chairs that I might be able to use for parts...

Josh

[Burgerman]

Cheap place for GOOD batteries? Or cheap batteries. Because the later is always a bad idea.

[LROBBINS]

Josh,

Given that you're in the U.S., there are lots of places to buy good batteries at prices far lower than from DME dealers. Odyssey batteries are a good bit cheaper than in the U.K. which in turn is much cheaper than in Italy. Ebay and Google, searching for brand names such as Odyssey (if you want maximum torque) or MK (if you want maximum cycle life) will turn up lots of re-sellers.

Burgerman is ABSOLUTELY correct, however - cheap(ly made) batteries end up very expensive. If you are a lightweight and smooth terrain user, you can get away with name-brand AGM (e.g. PowerSonic, Fiamm super-cyclic, maybe a few others), but if you want performance and longevity, at the moment no one's found better than Odyssey and MK. Odyssey, in particular, do demand a different charging profile than what mobility chargers generally provide. Gels and good AGM will have shorter cycle lives with typical "compromise" chargers, but Odyssey will suffer more. Burgerman's pages on batteries are a good place to start learning, followed by downloading the battery manufacturer's technical manuals if you want to get the absolute most from whatever batteries you get.

Ciao,
Lenny

[malamar]

Wonder, awoh, wooh, awoh... what happened with Optima batts , since not long ago another mass favorite...

[malamar]

she runaway,...probably

[Burgerman]

Optimas?

Weight for weight Odyssey and optima are pretty equal. Same pure lead low resistance technology, same charge algo etc.

But... Most powerchairs and all electrical battery powered vehicles have a big weakpoint. Batteries.

We need to cram as many watt hours, or Ah's as we possibly can in a fixed space.

The batteries that FIT and maximise the use of this space are the Group 24 / 34 sized ones. Same thing but for 1 inch height difference.

Now, the D34 Optima, is 55Ah. Whereas the PC 1500 Odyssey is 68Ah. So obviously the Odyssey is a better idea. More Ah, and because of this lower resistance, too, all in the same space.

Its for this reason that the idea of fitting a "similar capacity" lithium battery, where a much bigger one can be fitted is also a bit pointless. You lose the great advantage of the new lithium technology. ALWAYS maximise the capacity you can fit into the space. It has more than just range benefits. Like longer service life, lower average DOD, less strain (lower C rate) demands from the chair, etc etc.

[Josh]

Odyssey batteries are a good bit cheaper than in the U.K. which in turn is much cheaper than in Italy. Ebay and Google, searching for brand names such as Odyssey (if you want maximum torque) or MK (if you want maximum cycle life) will turn up lots of re-sellers.

sorry I have taken a while to respond to this post.
All the responses were definitely helpful, some of it over my head, but I'll read a bit more of the blog and maybe Wikipedia to educate myself a little.

Lenny, what do you mean by 'torque' in this context?

[LROBBINS]

Torque, in U.S. measure, is Ft-lbs. In terms of your wheelchair wheels, to use round numbers, if the diameter is 1 foot, the radius is 1/2 foot. If the maximum torque your chair can generate is 50 foot pounds, you would generate 50 pounds at the end of a 1 foot lever, but where your rubber meets the road you will have 100 lbs of force. Let's suppose that you need 100 lbs of force with the joystick full forward to start your chair moving up hill or on a difficult surface.

To generate 50 foot pounds of torque, the motor may draw 50 Amps, and the two motors will then need 100 Amps. Once the chair gets moving, the motor will turn faster, the torque needed will drop, and the amp draw will decrease. But to get started you need to be able to provide those 100 Amps. Odyssey batteries, because of their low resistance, will be able to provide those 100 Amps even after a lot of the stored charge has been used up. A first-rate gel battery, such as MK, or a good, but not Odyssey, AGM has a higher internal resistance but will probably be able to provide 100 Amps when it's fully charged. After you've been using it a while, it has less charge, its terminal voltage has gone down, and with the higher resistance you may not be able to draw 100 Amps and you may not be able to get the chair going.

In practical terms, Rachi's chair with decent, but not Odyssey, AGM batteries, was able to move on gravel when fully charged, but not after a couple hours' use. With the Odyssey batteries, gravel is no problem even at the end of the day. They would probably be OK on gravel with her light weight even after 2 or 3 days of typical use if I ever let the batteries discharge that much. Of course, because I want these expensive batteries to last a long time, I keep them as fully charged as possible - fully charging every night and, if use has been heavy, giving them a nice "drink" during the day as well.

To give another example. In power chair soccer, one hits the ball most of the time by turning as quickly as possible from a dead stop. Lot's of acceleration needed = lots of torque needed = low resistance batteries needed.

Ciao,
Lenny

[Lord Chatterley]

BM,
In the BM1, 2, & 3 there is a lot of alloy bar cut for spacers and struts - what cutting tool do you use to get such an accurate length of bar?

LC

[LROBBINS]

The lucky b-----d has a lathe in his bedroom!

[Burgerman]

Luck never entered into it. I scrounged it for a few beer tokens when my school dumbed down for the latest generation. They are no longer allowed to use tools because thats dangerous!

And they dont really need to be that accurate. The roast joints are very adjustable. Actually I keep looking at some black nylon rod (16mm diameter) thats propping the wall up. I suspect it would be lighter, easier to machine/dril/tap and plenty strong. No powder coating needed.

[Lord Chatterley]

BM, is that what you use then - the lathe? I imagined the alloy wheel spacers on the BM2 wheel adaptors would require a finely judged cut to prevent wheel wobble - unless you grind them all to the same length?

LC

[Burgerman]

If my measurements say I need say 18mm wheel spacers x 4, then thats what I make. Face 4 ends, cut to 20mm with hacksaw, machine every one to the SAME length by not adjusting the lathe for every one on the final cut. Just use the chuck with a flat bit of sheet metal to stop them going inside the chuck, and only move the cross slide. Net result is 4 or 8 spacers that are the same. They may be 17 or 19mm but all the same. No wobble.

But even just using the lath by eye, and "feeling" them against each other gets them close enough. These wheels are not that accureate anyway, and we only go slow.

[Lord Chatterley]

Thanks BM - that's exactly what I wanted to know.
Cutting off then finishing on the lathe struck me as a lot of labour and I wondered if you were using a circular saw to give a precision cut without the need to finish. These chairs certainly don't make themselves.

LC

[Burgerman]

You need a lathe anyway, after a cut, to face the end, and add a small chamfer, and to clean up with fine wet and dry, and metal polish unless you plan to powder coat?

All depends if you are building a scrap yard special, or doing everything to the best standards humanly possible. I do the 2nd. Most people are somewhere in the middle.

[Lord Chatterley]

You need a lathe anyway, after a cut, to face the end, and add a small chamfer...

Ah...I missed that...my mistake. Thanks.

LC

[Burgerman]

Of course you would have it in a lathe anyway to drill, and tap to M8 ready for the Rose Joints / rod ends, rubber couplings or whatever. So facing it, adding a chamfer, and cleaning up with steel wool or fine wet/dry is just the last job.

Mine are initially cut to slight over length (say 2 to 4 mm) by marking with my thumb, while I hacksaw them...

[ex-Gooserider]

Agreed, chop saws are not known for giving precise cuts - the kerf can vary considerably (especially with abrasive blades) not to mention the problems of getting the saw set up to cut a "perfect" 90* or other angle, and so on. Metal cutting band saws aren't much better for giving a straight cut - it is easy for the blade to flex a little and drift off the cut line by a few thousandths, especially if cutting a big block. Manual hacksaws can be better if on has good control, which most don't...

For rough work like carpentry or building shelving, where a minor error doesn't matter that much, it doesn't matter; but for any kind of precision work, the pattern has to be to do a rough cut to slightly oversize, and then trim it down to size with either a precision machine tool like a lathe or mill, or by careful hand work...

ex-Gooserider

[Burgerman]

Of course this is the WHERE TO FIND thread so these last few posts are going to be deleted. But you could easily build a chair using flat lumps of steel, or angle, and just drill some holes, use steel hex nuts and bolts. If function matters and how it looks, the standard of build/engineering didnt. This is cheap, and it "works" as any stock chair shows. This is what the manufacturers of powerchairs do.

[Lord Chatterley]

BM, what are the dimensions of the spacers for the BM2 wheel adaptors here

http://www.wheelchairdriver.com/power-wheelchair-off-road.htm

LC

[Burgerman]

They were whatever it took to let the tyres miss the motors by 2mm. Dont remember, but I did change from 8 to 10mm bolts after one snapped...

[Lord Chatterley]

BM, what are the dimensions of the spacers for the BM2 wheel adaptors here

http://www.wheelchairdriver.com/power-wheelchair-off-road.htm

LC

By eye, I would guess 16 mm alloy bar, 30 mm long, drilled 8 mm?

LC

[Burgerman]

now 10mm drilled.

[Fulliautomatix]

bolts nuts screws online for Australians.
http://www.boltsnutsscrewsonline.com/

[Neal]

Plastic caps to fit M6 screws for Headway cell pack building...


http://www.bpfittings.co.uk/pc/Hexagonal-Screw-Caps-Plastic-Allen-Key-Plugs-c3917.htm

[chris arnold]

I started doing a page here http://www.wheelchairdriver.com/powerchair-parts.htm

But kept getting sidetracked. So will link that page to this topic here.

So feel free to add links here. And to update and delete as needed.

Pride (overpriced) parts here in the US (Full parts and prices catalogue) http://www.southwestmedical.com/replace ... -mobility/

Sunrise (in the UK - There are others in other countries) http://parts.sunrisemedical.eu/uk/login/login.php use guest, guest for login/pass.

Give each post a new title so these links can be searched. And I will make this a sticky.

Tries the lower link, Sunrise, and got a 404 message = cannot be found.

[woodygb]

http://parts.sunrisemedical.eu/login/login.php

[Burgerman]

http://parts.sunrisemedical.eu/ fixed

[stevelawiw]

Anybody know where I can get a price for a Dynamic DX2-PMA90 controller?

Thanks
Steve

[LROBBINS]

Try googling on

Dynamic DX2-PMA90 UK

. When I did this, on the first page I didn't find any UK sites, but it did give one dutch site so you can at least see what the end-user retail list prices are:http://www.silema.nl/j15/index.php?option=com_virtuemart&Itemid=12&category_id=198&page=shop.browse&limit=20&limitstart=20

Dynamic does have a major operation in the UK, but they will probably not sell direct and will point you toward a WC manufacturer.

Ciao,
Lenny