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c6craig
10-03-2009, 03:46 PM
Hi All,

I use the chain lube with Moly to lube my flexshaft. On one of my machines, I lubed it about a month ago. The flexshaft does not get hot (warm only) during long carves, but I have noticed my Z-Truck getting excessively hot. I don't have an exact temp but it is hot enough to burn your fingers if you try to move the Z-truck over manually right after a carve.

I have read on the forum that this can be caused by lube seeping down into the top hat and to remove the top hat and wipe it down. When I pulled my top hat I see a light layer of what looks like rust, so my question is the oposite of the usual one - Do i need to lube the top hat with ANYTHING? Or just clean it up and put it back dry....

I was thinking of a light coat of 3-in-1 oil to clean it up and just leave a super light coat of that in there...but don't want to cause any damage.

Any help appreciated....pics attached.

Thanks,
Craig
mtylerfl
10-03-2009, 05:34 PM
Do i need to lube the top hat with ANYTHING? Or just clean it up and put it back dry....

Thanks,
Craig

Reminds me when I moved to Florida from Phoenix many years ago - my tools never rusted in Arizona - two weeks in Florida, EVERYTHING had a layer of rust on it! (I live in south Georgia now - rust problem is not quite as bad, but I do take precautions.)

Wish I knew an answer on your lube question - perhaps someone here has been in contact with LHR on that before and has an actual definitive answer. Otherwise, you should check with Tech Support to see what any lube recommendation is to help prevent rusting in the future.
Jeff_Birt
10-03-2009, 05:44 PM
If your Z-truck is getting that hot your top bearing is toast. (I've been there done that myself.) The rust is likely minute bits of pulverized ball bearings. Time to give CW a call to get a rebuilt Z-truck on the way.
c6craig
10-03-2009, 11:51 PM
Well Dang - Not what I was hoping to hear as this is Z-Truck #3, but thanks. I will give a LHR a yell on Monday, be a good test to see if I can get through with my new Carver's Club membership :)

Thanks for the help.

Craig
LollyWood
10-07-2009, 12:19 AM
Have new truck enroute. Was wondering if it's possible to pull the bearings?
Digitalwoodshop
10-07-2009, 12:33 AM
I would pull the bearing the un conventional way....

I would remove the plastic shield.

remove the plastic spacer

remove each ball bearing

Heat the center race and attempt to slide it off

Heat the outer race and attempt to slide it off...

New bearing and your all set....

I ordered the bearings about a year ago... They sent the upper one and back ordered the lower one then canceled the order....

Since it is a high speed bearing, you don't want any oil inside the bearing.

Good Luck,

AL
TWOATLOW8
10-07-2009, 07:51 AM
Do you have a Vendor and part number that you order the bearing from ?
Jeff_Birt
10-07-2009, 07:53 AM
NO HEAT is needed to remove the bearings from the shaft, they just press on and off. You need to replace the bearings and the tolerance rings at the same time AND you have to be darn sure to press the bearings in perfectly straight of you'll damage the tolerance rings (and they will fall out).

The bearings also have ceramic balls NOT steel due to the high RPMs.
dbfletcher
10-07-2009, 11:48 AM
NO HEAT is needed to remove the bearings from the shaft, they just press on and off. You need to replace the bearings and the tolerance rings at the same time AND you have to be darn sure to press the bearings in perfectly straight of you'll damage the tolerance rings (and they will fall out).

The bearings also have ceramic balls NOT steel due to the high RPMs.

Jeff,

Can you clarify you statements. You have two conflicting posts in this thread. In post #3 you say the rust is most likely bits of pulverised bearings.... but in the quoted post above you say the bearings are ceramic.

Thanks,

Doug Fletcher
Jeff_Birt
10-07-2009, 02:31 PM
Well, yes that is conflicting - good catch. The rust is most likely from the bearing (unit), the races, or I guess it could be from the heat causing the top hat itself to oxidize faster. I was originally thinking it was from the balls themselves. When the subject of replacing the bearings came up I recalled a conversation I had with one of the engineers at CarveWright about the bearings and he mentioned that they used ceramic balls due to the high speeds. I ordered the proper bearings after that (previously I just used some bearings that I had on hand), and replaced them along with the tolerance rings. I would not suggest trying to replace the bearings for most folks, it is a much better process to swap out the whole Z-truck.
dbfletcher
10-07-2009, 02:38 PM
Jeff,

That was going to be my next question... is it feasable for a user to replace the bearings. Would you need more than an arbor press? Not saying I would ever attempt this, but I always like to know what my options are.

Thanks,

Doug Fletcher
PCW
10-07-2009, 02:53 PM
Jeff,

That is interesting I didn't know that those bearing where made of ceramic. Is that the reason oil entering into from the tophat cause the spindle bearing to fail?

Found a pretty interesting article on ceramic bearings. Claim they can withstand up to 1600F
http://www.engineersedge.com/bearing/ceramic_bearings.htm
Digitalwoodshop
10-07-2009, 04:57 PM
Good Info Jeff.... Never pulled the top bearing and that makes sense and really is better to swap the Truck....

The oil and it's contamination are what gum up the works in my opinion.

AL