Steel City Bandsaw Table Trunnions Rebuilt
#8
  
A while back, I posted here asking about the possibility of replacing the broken trunnions on a 14" Steel City bandsaw I had been given.  Long story short, there were a few generic trunnions available online, but I didn't really want to take the chance of them not fitting.  Plus, I had an inkling of how I could fabricate my own.

One simplification is that I did not need the bandsaw table to be able to tilt.  So I just needed the table to sit solidly on the base.  I decided to use some hard maple blocks, sawed to the right radius, and attach them to the table with angle iron.  Here's the process:

   

Probably the hardest part was making sure the radius was a match.  I started by trying to trace one of the broken trunnions, but I couldn't get the block close enough to the radius to get an accurate trace.  So I just used the mating surface, like this.  I went ahead and traced out the whole radius, but in reality, only about a half of the radius is in contact with the base. 

I sawed out the radius on my old bandsaw (which I thankfully still have).  If I hadn't had that, I would have resorted to a coping saw.  

   

I clamped them together and smoothed out the saw marks with a file.  It doesn't need to be especially smooth or pretty, but the trunnions do need to be exactly the same size.  

   

After drilling through them and counter-boring the tops for the bolt head, they fit nicely onto the base!  The bolt hole is drilled oversize, which provides just a bit of wiggle-room in fitting everything together.  I probably should have also drilled the counter-bore a little bit oversize, too, but this worked. 

   

I used the old, broken trunnion to figure out how long each piece of angle-iron should be.  I attached the angle-iron to the wooden blocks with screws, and then I drilled out the oversize holes in the angle iron for the bolts that will attach the new trunnions to the underside of the table. 

   

Finally, I bolted the new trunnions onto the table.  I ended up putting in the bolts loosely, setting the whole thing on the base to get the trunnions positioned correctly (because of the oversize mounting holes, there's a bit of wiggle room), and then snugging down the bolts. 

Now, what you've read is the streamlined version of the process.  I had to make a number of little adjustments here and there, and there were some missteps along the way.  For example, when I went to bolt the trunnions to the bottom of the table, I found that they were just a little bit too wide, and while the mounting bolts fit okay, their washers didn't.  I think I forgot to factor in the thickness of the angle iron on both sides when cutting the blocks to thickness!  So I just use a grinder to take 1/8" off the edge of each washer.  Another funny thing: I accidentally counter-bored the wrong side of the trunnions at first (visible in the picture above).  But it doesn't affect how they mate to the base, so I just left it there.    

But now the table sits nice and secure.  Because the bolt holes are oversized, it is possible to adjust the table by a few degrees in either direction, which is just as well because I needed to use the set-screw to get everything leveled. 

   

So now the saw us usable again.
Steve S.
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#9
  Re: Steel City Bandsaw Table Trunnions Rebuilt by Bibliophile 13 (A while back, I post...)
Good job. Enjoy your saw.
Credo Elvem ipsum etiam vivere
Non impediti ratione cogitationis
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#10
  Re: Steel City Bandsaw Table Trunnions Rebuilt by Bibliophile 13 (A while back, I post...)
Cool  Looks like a great solution
Putzing, the new hobby

Evil lurks here, but eventually gets cleansed.


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#11
  Re: Steel City Bandsaw Table Trunnions Rebuilt by Bibliophile 13 (A while back, I post...)
Cool Cool

Great solution to the problem.
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#12
  Re: Steel City Bandsaw Table Trunnions Rebuilt by Bibliophile 13 (A while back, I post...)
Great solution! Good on you,

g
I've only had one...in dog beers.

If hummus is made from Garbanzo beans, why isn't it called Garbanzus?
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#13
  Re: Steel City Bandsaw Table Trunnions Rebuilt by Bibliophile 13 (A while back, I post...)
Excellent... glad it worked out.
Jim in Virginia
You can tell a lot about the character of a man -
By the way he treats those who can do nothing for him.
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#14
  Re: Steel City Bandsaw Table Trunnions Rebuilt by Bibliophile 13 (A while back, I post...)
Very cool. Now, not only is the saw made of cast iron, steel and granite, its made of wood too...
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