Unisaw trunion binding again, with pics

[Aram]

Thanks for the help you've given me so far, especially Skizzo. Issue has been elevation mechanism binding as I raise the blade. Well, as they say, I think I found your problem, sir....

With blade all the way down:



Closer view:



OK, I'm going to raise it now. Close up at before I do anything:



Start to engage rack:



Full engagement. Or should I say, cadging a ride. On top.



If you have experience adjusting this -- and I hope it can be fixed with an adjustment -- I would greatly appreciate your advice. Please tell me I haven't worn the teeth on the elevation rack down excessively ... right? This can be adjusted with a box wrench and a can of WD40, right?

Thanks once again.

[JGrout]

IIRC the shaft is moving from the front to the back At the back there is a large shaft collar and it appears to have moved. Bring everything back into alignment with the gears meshing and loosen the set screw and push it to the back of the saw tightly and snug it back down.

that should do the job of holding the parts in alignment.

Joe

[mike4244]

I'll give it a try,adjusted the worm gear to the trunnion a long time ago.
If I recall there is a nut on one end of the worm gear.Loosen the nut, push or what ever to mesh with the trunnion.Not to tight,you need a bit of play.Tighten the nut ,check the mechanism for tilt and height.Redo if necessary til every thing works to your satisfaction.Spray a lubricant like DriCote on the trunnion and worm gear.
All you are doing is raising or lowering the worm gear to mesh correctly with the trunnion.From your pics the gear teeth and the worm look fine. Normal wear is all I see.

mike

[Aram]

Joe - thanks. Now I get what you were trying to tell me earlier.

Mike -- thanks too.

Will try this later today. We'll see how it goes.

I appreciate the help.

[skizzo]

Something in the assembly obviously is slipping, eh? Seems like there are only three relevant parts in play here: worm gear, shaft, and elevation rack/arbor bracket.

It looks like the worm gear is pinned to the shaft with a roll pin, right? So the only way that part is problematic is if the roll pin sheared off between the gear and the shaft, and is sliding back and forth on the shaft. This doesn't seem likely, especially since your photos don't show any wear or markings on the shaft at the end of the gear.

The arbor bracket/elevation rack mounts onto a big steel stud up on top of the yoke, perpendicular to the direction of the shaft. It may be possible that something got loose in the trunnions or yoke mounting, which lets the bracket/gear move out of alignment over the range of its travel. I can't think of how it might be able to raise up higher, though, unless something is loose above.

That leaves the collars at the back end of the shaft where it goes through the rear bracket and trunnion. That was the point Joe and others made some time back. The most likely shifting is the locking collars coming loose around the rear trunnion, allowing the shaft to slide fore and aft over half an inch range or so. That means loosening both collars (assuming it has two), figuring out whether the forward or rear collar is the one that slipped, getting them both back in place for the rack range of travel, and locking them back down.

Nice photos, hope you get it figured out.

[Aram]

This can't be good, right? I pulled the rack.

[skizzo]

Don't think so... I don't know if newer model unisaws have changed the design, but all the older brackets I've seen have pretty much flat teeth. In metal rock-paper-scissors, steel beats cast iron. That explains how the teeth can get up on top of the gears.

Out of curiosity, does that arbor bracket casting show it as part #LTA-408?

[JGrout]

I agree that is not good at all.

And the saw is an X5?

I wish you all the luck in the world in your endeavor to find a new one.

It is not going to be an easy journey

the first two I went to look at say no longer available/ obsolete



I think you may have to just file the lands back open and hope that there is enough meat to operate the screw safely. That or figure on an expensive machine shop repair....

How long has this been going on? that looks like yrs or abuse.

Joe

[Lumber Yard®]

It may test your patience finding one at the right price but eventually Ebay will be your friend.

[Aram]

Hi Joe,

Yeah, when Delta was bought by B&D they cut off all supports for left tilt X4 Unis. You can't get arbors. You can't get brackets. Just nothing. They didn't even establish an agreement with a third party machine shop, which is dumb because someone could have made some bucks off of Delta replacement parts. This is my last Delta purchase, ever -- I realized that when my arbor stripped a whle back, and luckily for me, a skilled mechanic friend repaired it. B&D screwed its past customers, so, screw them. Which won't help me cut wood...

I'll have to get a quote from a machinist. Sadly I might start looking on CL for a PM66 or some old iron worth handing on to. My wallet is thrilled about this.

I'm not sure how long it's been going on. Maybe I've been in denial and ignoring it, I don't know. it does look like years of abuse, doesn't it.

I appreciate everyone's help.