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View Full Version : Problems with the tilt mechanism on my bandsaw



Staffan Hamala
04-10-2013, 4:45 PM
My bandsaw, a Proofy BS-330 (a 12" bandsaw, I think these were sold under many different names), has a tilt mechanism that doesn't really work as it should. I bought the machine used, and as I'm otherwise happy with it, I would like to fix this if I can.

The problem is that, although it's possible to tilt the table, you have to use excessive force to do so. Sometimes it just gets stuck and I've even considered using a mallet to get it to move.

Here's what I've found to be the root of the problem:

Although the table is cast iron, it is bolted to arched aluminium rails (or trunnions). There are a pair of long bolts that run through tubes on the saw's frame, and the aluminium "trunnions". The tubes protrude into the trunnions, but as these are in aluminium, they are a bit worn. As steel is harder than aluminium, the steel have eaten into the aluminium rails.

I first thought I would be able to file the tubes, but I've now seen that they are actually a bit too small. I suspect the problem to be the "drawer problem", where a drawer that is slightly smaller than the opening can get stuck if it isn't pushed straight in. I tried to add a layer of electrical tape, but that doesn't work (too soft).

I'm attaching some pictures below:
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Does anyone else recognize this construction? Do you have any ideas for how to solve this problem?

I bought this saw used, as an upgrade to my previous saw. This was an improvement in almost all respects, except for the tilt mechanism, which was smooth on my old bandsaw. I'm considering looking for another saw, but I'd like to see if I can fix this, before looking for a new saw.

Gus Dundon
04-10-2013, 5:00 PM
The trunnions are the mechanism that is used to tilt the band saw table. I wish I can help. Good luck.

Dale Coons
04-10-2013, 5:08 PM
If I understand the problem correctly, why not put a steel washer between the tube and trunnion? You might have to file or grind the sides of the washer so it will slide in the groove, but would that eliminate your 'too small' problem?

Steve Rost
04-10-2013, 6:15 PM
Are the tubes pressed into the trunion. Maybe you can remove them and replace with steel. The washer sounds like a good idea if it doesn't cause alignment problems when you tighten the bolts.

Staffan Hamala
04-11-2013, 1:05 PM
If I understand the problem correctly, why not put a steel washer between the tube and trunnion? You might have to file or grind the sides of the washer so it will slide in the groove, but would that eliminate your 'too small' problem?

That's a good idea! I'll try that! I had thought of using plastic tubing, or something, but as you say, a washer should be enough.

Bill White
04-11-2013, 1:05 PM
I agree with Mr. Coons. Shims after cleaning up the worn or scraped areas on the trunions.
BTW, who ever thought up the word "trunion"? :)
Bill