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motorworks
01-29-2015, 07:00 PM
I have a brush with a 1 1/4" steel shaft 3" long with a 1/4" key slot. (stub sticking out of the end of the brush)
The shaft can not be removed (very poor design)
I have to sleeve the shaft with stainless and bring it up to 32 mm x 1.5" long and then to 25 mm with an 8 mm key
The 25 mm part being 1,5" long.
My plan is to turn the 1 1/4" shaft down to 24 mm and shrink on a stainless sleeve. (0.002" tight)
The 8 mm key will end up in the 24 mm steel shaft helping prevent "spin out"
This is the drive end of the brush. The brush is 3 feet long with 12" nylon bristles driven via hydraulic motor
and love joy.
Sorry I don't know the torque.
My question is will this hold up or is the shaft turned too small.
(because of the nylon brush welding is out )

eddie

MTNGUN
01-29-2015, 07:13 PM
Too many unknowns to quantify.

But for a seat of the pants comparison, what is the diameter of the hydraulic motor shaft that is driving it?

If the alternative is to buy a new brush assembly then I guess you have nothing to lose by trying the sleeve.

motorworks
01-29-2015, 07:24 PM
Hi
Hydraulic motor shaft is 30 mm.
This is a new brush , came in wrong. Can not have exposed steel unless its stainless (food processing)
A replacement has to come in from Europe (2 weeks away) Ship wants to sail next week lol
I going to give it a try...done things like it in the past , but this time I removing more shaft
I need to get it down so the 25 mm part is SSA less what's under the SSA key !
eddie

becksmachine
01-29-2015, 10:23 PM
If I have this in my brain correctly, the 8mm key is going to cut completely through the wall of the sleeve, making any press/shrink fit of the sleeve on the shaft irrelevant.

Wild ass suggestion. Can you just build the existing shaft up with stainless weld? That may or may not satisfy the "no exposed steel" requirement.

Dave

motorworks
01-30-2015, 08:16 AM
No welding ....too close to plastic
The sleeve is 3" long
1.5 '' will not have a key ....
gone to do the job
eddie