PINNED NHS supplied Dietz Rehab Style Chair. You want one!!!

[Burgerman]

Good.

What is the 6mph motor impedance? Very interested. Check in programmer?
Trying to find out if their 6mph motors are any good. The 4mph ones are crap!

[rover220]

6mph usually set to circa 50 milli ohm

[Burgerman]

Thanks. Thats great. The issue is that the 4mph ones (I was too stingy to pay to upgrade to 6mph! I intended only using it at home) are 114mOhm.
Meaning that they are both battery inefficient, and lack torque and the load compensation doesent work well...

I was wondering if the 6mph ones were better. At 50mOhm they are! More than twice as good.

[steves1977uk]

BM, help!!! Trying to charge my Dietz chair with a PL8 but as soon as it reaches 28.2v (quickly) the current drops. The joystick shows 4 lights which means the batteries are pretty flat. I can't seem to get to remain at 12A for the bulk of the charge. The max I saw was 7.85A then it starts dropping. What am I doing wrong??? I'm using your Lead MK profile with cell count set to 12. Most puzzling!!!

Steve

[Burgerman]

They are gel/AGM and need 14.4V or even 14.6V dow a long thin wire really. And they are quite high impedance. So they soon reach that voltage. And so you are not doing anything much wrong. Even with the stock charger that rapidly fall to a few amps. They rely on float to finish the charge. Or the stock chargers 31V on every other charge!

BM, help!!! Trying to charge my Dietz chair with a PL8 but as soon as it reaches 28.2v (quickly) the current drops.

Thatscalled CC/CV. Its the battery and the thin wires that are the real issue here. Impedance.

If you discharge them deeply you will see they stay at 12A for a good while. Then they just charge slower and slower... Remember that you are charging down a long hin cable via XLR too. So the charger voltage soon sees the CV level while the battery doesent.


Lithium they ar not.

[steves1977uk]

Thanks for the info BM.

This XLR cable have always charged at 12A before. I switched over to using one of my ZXD units to charge this chair and the display is not budging from 25.23v @ 0.09A. The PL8 was doing better at 4A!

Is it possible this joystick XLR socket have gone high resistance? This chair has always been stored outdoors in a metal unheated shed, which isn't ideal I know.

Steve

[Burgerman]

Something somewhere maybe has.

If this battery is seeing the choosen CV voltage then theres nothing a charger can do to increase current. If that current is low then the battery or the wiring, or the XLR or something is either terrible or faulty...

[steves1977uk]

Yes BM, another weird thing is when I switched back to the PL8 after trying the ZXD the volts dropped and current climbed to about 6A but didn't get any higher. So there's something not quite right with this chair's batteries or joystick XLR port.

Steve

[Burgerman]

Anderson...

[shirley_hkg]

Sorry for the long wait.

Tubeless rims (8x3.5j) with flange adaptor, for Dietz Sango Advance, are done.

Will put on chair to ensure everything is alright before shipping.

[Burgerman]

For those wondering. These are TUBELESS rims that are the same as on my Salsa chair. They are 3.5 inches wide, to fit 120/70-8 TUBELESS tyres like the Duro ones. Shown below.

Shirley is making an adapter and supplying rims ready to go, no need to make an adapter. To fit the Dietz.

You can also fit 110/80-8 TUBELESS Duro tyres too. Slightly narrower and a fraction taller.

[Burgerman]

Alternate way to get a dietz chair for 1500... https://www.wheelchairdriver.com/board/ ... 59#p205459

[shirley_hkg]

Adaptor is made to as close fit as possible.

Have to hammer it slightly to engage bit by bit.

[Burgerman]

The 120/70 - 8 tyres are about 120 wide obvioulsly.
The rims are 3.5J so add 6mm (1/4 inch) width of metal makes a rim 4 inches wide externally. Or 101.6mm wide.

So the tyres are 120, rims 101.6 (call it 100 as we dont care about 1.6mm!) and so yes stick out 10mm wider than the rim each side. And thats good it protects the rims. Is there 10mm gap between rim edge and fender? If not then SEVERAL simple options exist.

1. A spacer on motor shaft. (A thick 20mm? steel washer from ebay...) (this is my option favorite!)
2. Some washers on wheel bolts innstead to do the same thing, less elegant and they fall out as you assemble! ...
3. Use 110/80 - Duro tubeless tyre instead and gain some in diameter and lose 10mm width. Both the 120/70 and 110/80 Duro tyres work well. They dont look as good!
4. Bin the guards... They dont do much anyway, and may hit tyres regrdless. 2 screws!

To finish this off neatly you need a 1mm thick stainless steel disk as a centre trim, cut out with a hole in it for the new polished stainless hub bolt...
It will be held in place neatly by new stainless wheel bolts and load spreading washers like this (5 per wheel, as a centre one is needed too in the Dietz) - centre one needs blue loctite:

[shirley_hkg]

It has enough clearance (>10mm) as per your measurement of 45mm offset from mounting face to tyre side wall.

I made the mounting plate 15mm thick, so you may trim it to close the gap without doing a new adaptor.

[shirley_hkg]

One thing may spoil it, if the 2 chairs have not identical setup.

The gearbox shaft has a 5mm spaces installed. Hope this is
not unique, only to her chair.

That's a aftermath correction obviously, itsn't it ?

[Burgerman]

Its always better to have an adapter that NEEDS a spacer. Because that allows you to use a smaller tyre and no spacer to make a narrower chair if required.

Or use a bigger spacer if needed for a wider tyre.

As it is, the space you show in your pics looks about perfect for that perfect Duro 120/70-8 tyre.
Likewise will be OK for the 110/80 tyre too. If the added height isnt an issue, as that tyre is slightly taller by a few mm.

Either way it looks great as it is!

What was the shaft DIAMETER? Pdf drawing and parts sheet shows 17 or 20mm? Depends on motors.
Some older dietz chairs have a smaller diameter shaft, with 2 pole motors. More recently they now only offer 4 pole across the range, on all 4mph, 6mph, 8mph so shouldnt be an issue.

Is the centre hub mounting bolt M8? or M10? How long? Need to order correct stainless parts! And a stainless 1mm disk.

[shirley_hkg]

Shaft is 20mm, 6mm key-way.

Centre bolt is M8x20.

[Burgerman]

Thank you. Thats what I needed to know. Will be ordering some bolts. Washers, load spreading spacers etc.

LOOK HERE!!! https://www.wheelchairdriver.com/board/ ... 94#p127194

Ordered
2x 74mm x 1mm stainless steel disks fir wheel centres. EBAY
10x alloy load spreading washers to fit wheels and hub. EBAY
10x 25mm Stainless M8 allen bolts to fit wheels and studs. ALREADY HAVE! (20MM ISNT ENOUGH WITH LOAD SPREAD WASHERS OR CENTRE DISK)
2x Washers, 7mm thick, to fit 20mm shaft as spacers in case they may be needed. I dont think so but cheap! EBAY
90 degree short tubeless tyre valve. EBAY

Hub/shaft will be greased to prevent future seizure (rust!)
Wheel Bolts also lightly greased
Hub bolt, blue loctite is essential here!

Tyres 120/70-8 Duro Kitaco. Already have a set I think.

So it looks like this WHEN ASSEMBLED: https://www.wheelchairdriver.com/board/ ... &mode=view

Parts...

[shirley_hkg]

Probably not. Nut and spacer that lock adaptor to axle will be sticking out. 15mm from end of axle, I guess.

They were hidden under
stock rims.

[Burgerman]

Well that will look bad. I will modify!

But here it looks flat, with 1mm recess for stainless disk. Disk will need 8mm hole. So will end up with 4 wheel bolts and 1 hub bolt. So 5x M8 bolts. All same, each wheel. So it looks neat! You will see.

5 of these bolts, (M8 x 25mm long allen, (stainless)
5 of these load spreading washers each side/wheel. (grey anodised aluminum)

4 in the rim, 1 in the centre through the stainless disk. Each side.

This

This...

Then this - stainless 75mm disk - needs 8mm hole drilling in centre :

DRILL HOLE IN CENTRE! 75mm disk, 8mm hole

Then 5 of these each wheel inc a centre one!:

[Burgerman]

Heres an OFFICIAL dietz sango advanced chair with their "off road" kit ordered.

This one has a very small seat for a child. But ignore that.

What is different?
a. Rear fenders/guards are different. Different part number to accomodate these 16 inch tyres.
b. stock too skinny rims are used (1) with 4.00 x 8 tyres/tubes. This gives a taller tyre (2 inch bigger diameter, 1 inch taller ride height. But they are "pinched" inwards and so the full 4 inch width ends up narrower and the tyre tread is pulled around the sides slightly. (They really needed wider rims. Like the shirley adapter/rims).
c. Stock front rims, with bigger 3.00 x 4 (10 inch) tyres as used on my BM2/3 /salsa chairs.

So if you decide to fit the rims I used on the salsa, with shirleys adapters then you can order the matching front tyres (ebay) and the bigger tyre guards (dietz) to match. You can the use either the 4 inch tyres below that fit the wider rims properly, and have 16 inch drive wheels, and be tubeless, or fit the better Duro 120/70 tyres and have slightly more width at 5 inches, lower profile and so 14.62 inch diameter so only slightly bigger diameter than stock. So stock caster size and stock guards can be used.

****************
With skinny stock rims 4 inch tyres and tubes, 3.00 x 4 front tyres. Tiny seat here! Ignore that.

[ICEUK]

bm, how wide is the dietz chair with the duro tyres on?

[Burgerman]

Dunno yet! But its very narrow at the moment. So much so that it seems to lean too much as you traverse uneven surfaces. I expect it will be about 27 when fitted with 120 tyres.

[iainsherriff]

Probably not. Nut and spacer that lock adaptor to axle will be sticking out. 15mm from end of axle, I guess.

They were hidden under
stock rims.

Shirley ...... can you post the dimensions of the adaptors please. So i can check if the wheel offset will suit Matt's Invacare RX20


thanks.

[Burgerman]

Does it have parallel shaft 20mm diameter?
If so then spacers behind the hub or rim, can be used to adapt the adaptor

[iainsherriff]

Parallel but 19mm.

Just thinking a base/starting point may make ordering easier ..............

[Burgerman]

Then no go...
Making an adaptor that fits between stock hub and new rim is easy enough though.

[shirley_hkg]

BM's 120 tyre is 45mm offset, from mounting face to barrel end of adaptor.

Instead, this is the offset of a narrower 3.50-8 tubeless tyre and rims, that most people use.

[Burgerman]

That appears to be a narrower rim /wheel + 3.50-8 tyre.
I use the 120/70 tyre (4.9 inch wide lower profile). On a wider 3.5J (4 inch externally) rim.

In any case be aware that the rims are not the same width. Mine is a 120mm (4.9 inch) wide tyre on a 3.5 inch wide rim (overall rim width 4 inches, 3.5inch between beads)

The one in the photo above is a 3.50 tyre on a narrower 2.5J rim.

And that overall diameter is very similar in both cases with the wider wheel/tyre being a fraction smaller diameter and still slightly bigger than the stock 3.00 tyres. And the 120 duro tubeless tyres are much tougher.