Stump Grinder -Shaft

[FLtreeGuyVHTC]

I was wondering about the 630 b shaft parts, bearings, and how spacers and bearings are placed. We had the Amish work on my grinder and they did more damage then they fixed. I can post pictures of my cutting wheel shaft and bearings. I really need to get this fixed correctly before someone gets hurt.

 

[gorman]

If they're not building your barn or bed don't use em

 

[FLtreeGuyVHTC]

Kind of a given now. Vermeer says there are metal shims and washers but from the pics they sent I couldn't see how the bearings went on. They say their not pressed on but I can't get them to come off.

 

[treeclimber101]

You may need a hot wrench .

 

[FLtreeGuyVHTC]

Def. of "hot wrench"?

 

[les-or-more]

Def. of "hot wrench"?

Heat.

 

[FLtreeGuyVHTC]

Heat will damage the bearings. I've been told a large there point puller should work after talking to a local mechanic. If they just slide on they should slide off... ?

 

[treeclimber101]

You'd think it was that easy but you can't pull a bearing without taking out the cage believe then it's pointless to proceed just figure new bearings

 

[FLtreeGuyVHTC]

Yeah I need to price check those. Amish charged $350 just for bearings... Rather not throw away brand new ones if possible.

 

[les-or-more]

Heat will damage the bearings. I've been told a large there point puller should work after talking to a local mechanic. If they just slide on they should slide off... ?

Heat can be applied without damaging the bearings if you are careful, I assume these are new bearings improperly installed? Is there room for a bearing separator? behind them so they can be pulled without damage?

 

[treeclimber101]

If my memory serves me properly there like 3 fingers behind those bearings at most ..... I did them on a 665B a huge tow behind and they were a nightmare

 

[les-or-more]

If my memory serves me properly there like 3 fingers behind those bearings at most ..... I did them on a 665B a huge tow behind and they were a nightmare

Are they seated against a shoulder?

 

[treeclimber101]

Yes ...

 

[les-or-more]

Yes ...

Are these bearing in pillow blocks? Do they have set screws? I know its not yours, just trying to answer all the questions and op is awol.

 

[FLtreeGuyVHTC]

Yeah pillow blocks. Yes they were installed back words... Which makes it so the wheel is way to close to the main frame

 

[FLtreeGuyVHTC]

Im almost home and will post pics if possible

 

[imagineero]

liquid nitrogen is another option. It's how we fit the (big) bearings and sleeves that are a crush fit into the 1000 tonne face shovels in the mines. The cold shrinks the bearing, pops right on or off. It's not as scary or expensive as it sounds. Your local plumber will know someone who has it. They freeze mains pipes to work on them. Alternatively if you can borrow a cannister, the LN itself it very cheap.

 

[FLtreeGuyVHTC]

Seems like a good idea. I'd have to get the machine to room temperate and just the shaft because if the bearing shrinks it will just sit tighter on the shaft. The mechanics is going to let me borrow his there point puller. It looks like a pulley puller but 3 adjustable claws and much larger.

Out of curiosity... What kind of grinder is everyone else using? Ours has been around a long time.

 

[imagineero]

it's counter intuitive, but steel shrinks towards it's centre and doesn't know it's shape. So a shrunk bearing will get smaller in OD and larger in ID.

Makes no sense I know. Way it was explained to me was; if you got a bit of flat bar and froze it, would it shrink on one side, or all round? It would shrink all round! A bearing is just a flat bar bent into a circle. It doesn't know it's a circle, it still shrinks all round.

By pleasant coincidence, the shaft also doesn't know it's a shaft and will shrink too (though not much), meaning they shrink away from each other.

 

[FLtreeGuyVHTC]

True. Density and surface space makes this true. I'll give it a shot. I was thinking about trying to heat the shaft up and use the puller but that will cause it to expand. Thanks. All good ideas