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badbert
10-12-2012, 03:11 AM
So I tore "Bucky" apart tonight for some TLC. The Z truck was getting noisy, clunky movement. I suspected a broken gear, or a frozen bearing. Instead i found some lumpy Rails. These things are hardened, aren't they? They sure were a nightmare to get smooth again! I had to resort to 220 grit. And stroked them for an hour or so! The look on my wife's face was priceless, when she asked me what I was doing. (Hands in my lap, staring at the computer screen, watching a movie...) Anyway... I had time to ponder how something so hard could get worn so fast.

Awhile back my QuickChange gave up my only Carving bit. I found part of it embedded in a carving. I was able to get the Old Z-truck off and put the new CarveTight Z-truck on without having to deal with the loctite. But 45 minutes into the second carve (First one ruined by the bit) I noticed the sound had changed, and found the Z-truck was rattling. I took it back off, drilled out the screws, and bought some allen head grade 8s. I used the red loctite and reinstalled the truck. But in my fear of it coming loose again... I think I over-tightened the bearing adjustment. Forcing them into the rails. There were definite grooves worn from the bearing movement.

So did I over-tighten, or is this normal wear? There is around 400 hours on the cut motor. The Y truck moved smooth and there doesn't seem to be excessive wear on them.

PCW
10-12-2012, 07:44 AM
Sounds like you over tighten the bearings. The bearings need to be preloaded to remove any slop but still allow them to move freely. Don't know how bad the rails were worn but you might have been able to rotate the rails 180 degrees to get a fresh surface. Also I would avoid the red loctite and go for the blue. Lot easier to remove down the road.

badbert
10-12-2012, 08:20 AM
Thanks PCW, I was tired when I wrote that. I did use blue, the semi-permanent one. Floyd set me on the right path.

I thought about turning them 180 but the displaced metal was what the truck was clunking on. as it slowly wore away the metal, the bearings pushed the metal to the bottom of their movement. So the shaft was actually .002 thicker in those areas.
Working silky smooth now. I think I over tightened them too. Just wanted to confirm the wear was not normal. I noticed while disassembling it, that when I loosened the bearings, they rolled right over the lumps. That's why I assumed they were too tight. The good news is the bearings were all fine.

Digitalwoodshop
10-12-2012, 12:15 PM
Have you ever Cut any of the New Pressure Treated Wood with it's copper based STEEL Eating Chemicals?

I recommend against cutting or Carving the New Pressure Treated Wood.

AL

karossii
10-12-2012, 12:44 PM
The look on my wife's face was priceless, when she asked me what I was doing. (Hands in my lap, staring at the computer screen, watching a movie...)I can just imagine!


Have you ever Cut any of the New Pressure Treated Wood with it's copper based STEEL Eating Chemicals?

I recommend against cutting or Carving the New Pressure Treated Wood.

ALWhat wood is this?

Digitalwoodshop
10-12-2012, 02:08 PM
The wood you use to build decks with that has a Preservative inside it... Called Pressure Treated wood....

http://en.wikipedia.org/wiki/Wood_preservation

http://www.naturalhandyman.com/iip/infxtra/infpre.html

b.sumner47
10-12-2012, 02:26 PM
Al, Are you sure about the copper reacting in adverse way with iron ? I've known of a bad reaction with alumimun, not iron or steel. There is a warning of copper and aluminum having a seriuos reaction in the boating world. Just wondering .


Capt Barry

bergerud
10-12-2012, 02:33 PM
I have noticed that my z rails rotate. They have marks on them which clearly indicate that they rotate during use. This rotation would even out the roller wear. Maybe the problem with badbert's rails was that they were not rotating. Maybe non rotation is a symptom of having the rollers too tight.

Has anyone else noted that these rails rotate?

badbert
10-12-2012, 03:04 PM
Have you ever Cut any of the New Pressure Treated Wood with it's copper based STEEL Eating Chemicals?

I recommend against cutting or Carving the New Pressure Treated Wood.

AL

I try to avoid chemicals of any kind. Much less grind them up into fine dust! I have COPD. I have been afraid of treated lumber since the cyanide scare!


I have noticed that my z rails rotate. They have marks on them which clearly indicate that they rotate during use. This rotation would even out the roller wear. Maybe the problem with badbert's rails was that they were not rotating. Maybe non rotation is a symptom of having the rollers too tight.

Has anyone else noted that these rails rotate?

AHAA! that would explain the black marks underneath the rails. Maybe they are supposed to turn.

PCW
10-12-2012, 06:03 PM
I have noticed that my z rails rotate. They have marks on them which clearly indicate that they rotate during use. This rotation would even out the roller wear. Maybe the problem with badbert's rails was that they were not rotating. Maybe non rotation is a symptom of having the rollers too tight.

Has anyone else noted that these rails rotate?

I have never notice any movement on the rails before. My thinking is if the rails are loose enough that it would allow the rails to spin that there is not enough tension on the bearings and would cause some run out. Can you feel any movement in your trunk? Just my thinking

fwharris
10-12-2012, 10:14 PM
For tightening the bearings I've always gone with Al's method of RED polish/paint/whatever on the bearing nut edge that when installed would be in the fully adjusted closed position when the RED faces straight out from the edge of the Z truck. I believe this is also the method used by LHR. ??

I've always heard the Z rails were suppose to float but did have to rotate mine a while back. Did have to dig and wipe out a good amount of gunk from the indents for the rails, probably residue from over lubing the rails.

The Y rails do not rotate as the two end screws and washers clamp down on the rail ends. I've rotated mime once and have a set of new Y and Z rails on hand.