Unisaw tune up probelm

[Don Newman]

I have a 1970’s left tilt Unisaw which I can’t tune properly. When I crank the blade all the way right, it is still a slightly shy of 90 degrees to the top. I can’t get the blade vertical. When I remove the top I can see that the stop nut on the front trunnion is not the cause of the problem. It is still a quarter inch away from the limit. It appears that the worm gear is at the end of the worm drive and can’t go any farther. Any suggestions on how to fix this or what to do next?

[Maurice Ungaro]

Have you totally de-gunked the mechanism? A good build up of saw dust and grease can have the same result as a stop screw.

[Don Newman]

Thanks for the thought, but hat's not the problem. I should have mentioned that I gave the saw a thorough cleaning and lubed everything.

[Jeff Horton]

Since I just rebuilt one I keep going over this in my head and I can't understand it. My fist assumption is there is something (trash, sawdust, woodchip) somewhere in there that is causing the problem. Nothing should stop it before it gets to the positive stop. Be sure and check all the not so obvious places! If you have an air house blow everything out.

Tilt the saw towards 45 and check the groove the trunnions ride in for a rough spot or anything in them. While you have it apart coat the groves with some lubricant. Heck lubricate everything, that might be the problem. Just keep looking till you find what is stopping it. This is just me, but if I couldn't find it I would be tearing it down, because there is something wrong somewhere. And Unisaws are pretty simple to work on.

We know it didn't come from the factory this way. So that means something has happened to it. If the cabinet is not bent or damage, there are not broken parts, has to be something limiting it's travel.

The only other option I can come up and I don't like it, is to shim the table top. But that is not fixing the problem, it's just curing the symptom.

[Jeff Horton]

I was thinking about this some more, and if I remember correctly the 90 degree stop should be the only thing that stops the trunnion at all. If it were not there you should be able to run it till the teeth disengage. The 45 degree end had a stop in the casting.

Anyone know for sure? I might have that backwards but I don't think so. But if that is right, then there is something limiting the trunnions travel.

[Don Newman]

Following Maurice's & Jeff's suggestions I took a toothbrush and compressed air to the trunnion and worm gear. Something I couldn't see must have been the problem because the stop nut is now the at the limit. While I thought I had it clean, obviously I didn't.

I haven't put the top back on yet so I can't confirmed the problem is solved, but I sure think so.

SMC sure is a great resource. Thanks a lot.

[Jesse Cloud]

Next time they have one of those "What's your favorite tool?" surveys, I think I'm going to say 'an old toothbrush' - they have solved a lot of problems in my shop :rolleyes: .