Broke Mill...need advice

[Larry]

Little over a week ago bands started wandering around on my wheels.  Went through the alignment steps and seemed to take care of the problem.  Few days ago the drive wheel and shaft made an attempt to come out of the machine which was the cause of the wandering bands.  In the picture I think you can see the bearing is locked on the shaft with an allen screw...one on top and one on the bottom.  The bearing also is a light press fit on the shaft...but not anymore.  The shaft is wore were it spun in the bearing.  Measured the clearance at 6 thousandts. 



The mill was sawing perfect lumber when it quit.  So I guess I could just tighten up the allen screws, put it back together, and start sawing again. :-\  Or is the shaft fixable?  Or should I bite the bullet and buy a new shaft? :'(

Gotta look at the good side...it's gonna be easy to put the speedometer sensor in the wheel now. ;D

[RichlandSawyer]

Thats a tough call there Larry, but if the shaft is ground  then the inside of the bearing is ground so you'ld have to replace both anyway. If it were me i'd give her a dab of locktite, crank down the set screws and run her till she drops. Cant hurt anything anymore than it already is!! First though i'd make sure that bearing is turning free, that may have been what spun the shaft in the first place. once the bearing heats up it may start to stick.

Good Luck RS

[sawwood]

Larry not sure what size shaft it is, but may be you can find one of
thoes sleve repair kits for crankshaft damper on car engines. Take
it to Napa or outher auto parts store and see if they have one that
size. If you could chuck it in a lathe you might braze the shaft and
then turn it back down to the size to fit the bearning. But if all ealse
just buy a new one and bearing.

Sawwood

[Percy]

Larry not sure what size shaft it is, but may be you can find one of
thoes sleve repair kits for crankshaft damper on car engines. Take
it to Napa or outher auto parts store and see if they have one that
size. If you could chuck it in a lathe you might braze the shaft and
then turn it back down to the size to fit the bearning. But if all ealse
just buy a new one and bearing.

Sawwood

What Sawood said. You might try a heavy truck shop for the repair kit. We used them alot on ujoint yokes on rearends trannys etc. Comes with an instalation tool and all...

[LeeB]

if you decide to re-use your shaft you might try drilling a dimple in the shaft where the set screws seat.

Do these kits fill in a spot in the middle of a shaft?
LeeB

[Lenny_M]

You could knerl the shaft and assemble with quick metal. If the bearing is a pillow block or flange bearing you can replace the insert only.these bearings are a slip fit and generaly not pressed on.
you can get the same effect of knerling by using a center punch and making dimples on the entire dia. of the shaft. worn only .006 is should work ok. Just hope you don`t have to take it apart again, that stuff holds really well

Quick metal expands as it sets to a press fit
      Lenny

[Fla._Deadheader]

I have repaired all kinds of stuff, and would rather fix than replace, BUT, this time, if that were my mill, I'd replace the bad parts.  : I believe you have sufficient tension on the shaft to have it happen all over again, Once would be too much for me. CAN'T be THAT 'spensive.  ;) ;D

[mike_van]

I gotta go with Fla. deadheader on this one -  I would replace the parts too, unless the cost was astronomical  or you just plain needed it NOW -

[Frank_Pender]

Larry, my father use to say, "You can walk over the dollars to save the pennies."  ;D Just a thought.

[OneWithWood]

Find out if you can turn the shaft and get a .001 oversize bearing.  Then either replace the shaft and bearing or turn the shaft and get the correct size bearing to fit.  Whichever is least expensive.

[VA-Sawyer]

I would polish the shaft a little and use some stainless steel shim stock.  I would also use the black Locktite super glue between the stock and the shaft.  Then I would start saving money for new parts.  This will at least get you back up and running fairly cheap and fast.

[Larry]

Thanks guys for giving me options.  I thought the Micro-Sleeve sawwood suggested was a great idea but couldn't find the right size.

The knurling and Loctite Quick Metal Lenny suggested was another great idea as it is specially made for just this application and should have worked perfect.

Just got off the phone with the factory.  They added longer allen screws with lock nuts and also drill the shaft now.  One thing we talked about is if the band wheel had or developed run-out from the old worn shaft I would start breaking bands...and it might happen intermittently which would make diagnostics difficult.  So...a new shaft and bearing is headed this way as I write this. $150 including shipping is not bad to put the mill back in perfect condition.

Going to go ahead knurl and Quick Metal the old shaft and bearing just to have a spare.

Again thanks for the ideas.