Permobil F5/F3 shaft size & offset.

[shirley_hkg]

Being asked to fabricate adaptor for aPermobil to go tubeless.

Would like to know the shaft size, length, straight or taperred.

[shirley_hkg]

Length of original hub too would be great.

Belows are offset of tubeless candidate.

All inputs are appreciated.

[Burgerman]

What is the width of that rim between tyre beads?

[shirley_hkg]

Yours is the lowest one.

[Raro]

I would measure it for you, Shirley, but I don't have anyone to do it for me. What tire are you going to use, 3.50-8?

[shirley_hkg]

Thank you so much

Tyre profile will be at user's discretion, whereas we have choices other than 3.50--8 as mentioned.


https://www.wheelchairdriver.com/board/ ... 3&start=30

[Burgerman]

I know what mine is, as its a 8 x 3.5J rim. 3.5 inches between beads.

I mean which size do you use for the 3.50 inch wide tyre? Now I know. 2.75 inches.

[shirley_hkg]

Inputs are appreciated.

[Raro]

Maybe you can ask someone who has an engine for sale if they can do you the favor of measuring it like in this ad...

https://www.ebay.com/itm/135009251931?i ... AOSwM45lrY cK&itmprp=enc%3AAQAJAAAAwCodCO1vSDjg2xNOt8By6oCc%2BB5fotidNTv5iCC8YlfZDRgnGQPmkAxJtnyx3AkoPqnPvQeIybBN2VSgAzz kP85PD3FIzh2M1W5X8XKwSccBng1fJ1D%2BMbV4a0l7G29wCXdfThYb7aork1Ws%2Fa4enD2vHgH2ZWsvzrVKQToSew4qaW10xSd81doUhpuC zHr6aw9O%2BXg%2BxoebrWkm1I7sXOMonY5FH2w83ngD6CMsUxOU6yByQYlAQKu%2FQE1%2B%2BTm6RA%3D%3D%7Ctkp%3ABk9SR5rDif6dZQ

[shirley_hkg]

Actually, I'm asking for a hub on ebay.

[Raro]

[slomobile]

The shaft is a weird 3 faceted taper. I wouldn't even know how to describe it other than that. Not easy to machine a hub for.
https://youtu.be/64QZITH3sjk?si=9xuGXZy3AMRgJukk

If you really need a measured drawing after seeing that video, ask me again and I'll pull a wheel off and try to get you enough measurements. But I think it would be lots easier to just use the stock hub.

[slomobile]

https://youtu.be/uVGRkw1Pa_w?si=oeGgiJ3_O8x55zW7

[Burgerman]

If you really need a measured drawing after seeing that video, ask me again and I'll pull a wheel off and try to get you enough measurements. But I think it would be lots easier to just use the stock hub.

All my chairs use an adapter bolted to an existing hub apart from 1 of them. This works OK on wider rims as theres enough space to do that. If you are swapping rims for narrow ones just to go tubeless then its not so easy. But I always use wider rims. Looks better, works better, rides better, so why go narrow?

Generally use 120/70 - 8 tyres (duro) on 3.5J x 8 rims on modern chairs now. Strong, tubeless, wear extremely well, better ride, never a puncture, shirley gets rims (or ebay super cheap) tyres are not cheap And they look good too!

[Raro]

It would be best to measure the axis of the chair that is going to be modified since perhaps depending on a date the production varies and it is different, I have never seen one like the one slomobile indicates.

[shirley_hkg]

The shaft is a weird 3 faceted taper.

Thank you , Slomobile

That's really not easy to replicate, but I do appreciate Permobil super strong design.

It's only feasible to use original hub , and modify it to take tubeless rims. So I need two hubs.

Don't bother to take measurement, pal.

[Burgerman]

Just make an adapter that bolts on. Flat disk, some countersunk holes. 3 countersunk high tensile bolts. And then threaded holes for new rim.

Thats how most of my rims bolt on. Easy cheap no new hub needed. To fit the 120/70 or 110/80 tyres, with 3.5j rim it normally needs to be 8 to 12mm thick and thats easy and cheap.

[jefferso]

So that hub is part 18 in this exploded view, correct?

https://explodedviews.permobil.com/catp ... ditid1=364

It says:

Code: Select all

New Part Number  Old Part Number  Description
NULL             323404           HUB O22x28,5

I haven't seen one on ebay yet.
I wonder how much Permobil charges for them.

[shirley_hkg]

The guy said 2019 model in the video.
Mixed information.

Not advise to take chance.

Take wheel off and confirm.

[jefferso]

The F5's distance from outer edge of tyre to inside of wheel surface looks like 2.9cm.
Not sure when I'll be able to get the wheel off, hopefully soon.

[shirley_hkg]

NO.
You can't measure it right without taking the wheel off.

[jefferso]

Is this not the equivalent measurement to this one (3.45cm)?

https://www.wheelchairdriver.com/board/ ... 33#p207665

Will it be significantly different when the wheel is off? Because of the tyre bulging from the weight of the chair?

[Burgerman]

He is trying to get the measurement from the tyre INNER face, to the surface the wheel bolts on to.

So with the same wheel, would be different with a different tyre. Even tyre pressure changes this a little.

[shirley_hkg]

He is trying to get the measurement from the tyre INNER face, to the surface the wheel bolts on to..

Right.

The way Jefferso measured it has 2 questions ,

1, he assumed the split halves are of the SAME thickness. It's not uncommon that rims halves are one of the halves is thicker than the other.

2, Jeff has to deduct the thickness of metal in the middle, in order to get the right offset, even with identical rims halves.

[jefferso]

I am looking for a trolley jack to lift my chair so I can take the wheel off to get some more measurements. I have a Permbol C500 and a Permobil F5. I think the F5 has around 75mm clearance and the C500 has around 80mm clearance. The low profile jacks I've seen seem to range between 70mm to 85mm for the minimum height and tend to be a bit more expensive than those with a higher minimum.
I guess if I got one that had 80 - 85mm clearance, I could always roll the chair up onto something like a couple of pieces of wood to get a bit more clearance to roll the jack under. Most of the lower profile jacks seem to weigh around 30kg but Halfords has a 1.5 tonne aluminium jack which seems to weigh substantially less https://www.halfords.com/tools/garage-w ... 39390.html with 80mm minimum clearance.
I saw a jack on ebay which claims to have a clearance of 73mm and weighs about 32kg.
Does anyone have a recommendation for a jack?

[shirley_hkg]

Got a patient lift ?

Lift chair by one of its tie down .

[jefferso]

I have a ceiling hoist. The hoist itself has a weight limit of 272kg, but I'm not sure how much I trust the strength of the mount of the track into the ceiling. Plus it's in the bedroom where there's carpet. Probably fine to do it once or twice but I've wished I had an easy way in the past to check things out under the chair so was thinking I'd like to have a jack available.

[Burgerman]

I use my ceiling hoist, or a patient lift, or if its just to take a wheel off I pull the chair over onto its side. Throw a few pillows onto the floor first.

In any case you only need lift one side, so about half the chairs mass. Any of your lifts will be fine.

[shirley_hkg]

I lifted the entire chair with ceiling hoist.
Chair weights 220kg, so one wheel off is around 110kg.

Take hub off to check motor shaft as well.. Straight or triangular taper.

[jefferso]

I have a service manual for F5 VS but I think it's old. It says that the wheel hub requires an Allen socket, 6 mm to remove. I got someone to take the wheel off to get measurements and was going to take the hub off too but the allen key bolt is larger than 6mm and I didn't have an allen key which would work so couldn't take it off to double check. Not sure if it's 7mm or something imperial?
The chair was manufactured in May 2022 so pretty sure it would be the triangular tapered version.

The tyre, when off the chair, flat on the floor, is 74mm thick.
From the outer edge of the tyre to the outer surface of the rim where the bolt hole is, is 29mm.
The metal of the rim seems to be 6mm thick.
From the inner surface of the rim where the bolt hole is, to the inner edge of the tyre is 39mm.

It's about 64mm from the outer surface of the hub to the black plastic inside the chair.
The motor sticks out beyond that black plastic though, and that seems to be 49mm from the outer surface of the hub.
So it looks like 49mm clearance from the inner surface of the wheel (which is pressed against the outer surface of the hub when bolted on).

hub

hub showing motor which sticks out a bit towards the inside edge of the tyre