Rebuilding Trunnions on a 14″ Steel City Band Saw

Not long ago, a friend offered to give me his old bandsaw, which he was replacing with a newer, bigger model.  The only catch: the old bandsaw had two broken parts, and because the manufacturer has gone out of business, replacement parts were not available.  I accepted the offer anyway.  This is the story of how I fabricated replacement parts out of commonly-available materials.

The bandsaw is a 14″ model, built by Steel City.  The broken parts are the trunnions, which are the curved pieces that attach the table to the base and allow the table to tilt in order to make an angled cut.  Although this bandsaw is solidly built, I understand from my internet research that it’s not uncommon for the trunnions to break.  They’re just made from pot metal.

Bandsaw Broken Trunnion 2018

This is the underside of the bandsaw table, and you can see how the curved parts have just crumbled away.

Here’s how I made my own replacements for these parts.

First, I should explain that, while the original trunnions allow the table to tilt, I really don’t need that feature. I just need the table to sit solidly on the base.  So I made replacements with  some hard maple blocks, sawed to the right radius, and attached them to the table with angle iron.

Bandsaw Trunnion Repair 2018

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.

Bandsaw Trunnion Repair 2018

I clamped the two pieces 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.

Bandsaw Trunnion Repair 2018

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 did have to buy longer bolts, too.)

Bandsaw Trunnion Repair 2018

Each trunnion is attached to the bottom of the table with three bolts.  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.

Bandsaw Trunnion Repair 2018

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 for a confession: what you’ve just read is the streamlined version of the process I actually went through to fabricate these parts. 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 I had made them 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 used 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 securely. 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.

Bandsaw Trunnion Repair 2018

So now the saw is usable again.

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24 Responses to Rebuilding Trunnions on a 14″ Steel City Band Saw

  1. potomacker says:

    I think that your repair is remarkable but I must ask about your opinion of the Steel City. Frankly, if a critical piece of my machine broke, (the casting looks undersized and faulty) I would ave doubts about the rest of the parts, too. Serious doubts and concerns. Did Steel City not offer to replace the broken parts?

    • I should have said in the original post that Steel City is out of business. Normally, yes, they probably would have sold me replacement parts. The owner’s manual even has detailed exploded diagrams with part numbers for every piece. But, alas, once the company shuts down, those part numbers are useless.

  2. Goes right along with your (and our) philosophy of using recycled, repurposed wood. Never throw away if it can be used or fixed, and there is usually a way to build it in wood, no matter what the original material.

  3. Arthur De Lorenzo says:

    Firstly I would like to mention my appreciation for your dedication to repair that machine. Most people would just throw the thing out and buy a new one. I strongly disagree with the current view of society that everything is buyable and when things break you just toss them away and buy a replacement. This process is both inefficient from an economic point of view and it also has a great burden on the environment. I am a fan of fixing stuff up or repurposing old stuff and I like the fact that you show people that broken stuff could be fixed by your own hands. Keep up the good work!

    Kind regards,
    Arthur De Lorenzo

  4. Roy de jong says:

    Hey, why didn’t you choose to weld te table back to the base ( don’t know if you have the equipment to weld). In my opinion wood on steel connections aren’t always the best and there will be always some frictions. I olso read that you made this solution because you don’t need the possibility to tilt the table. When i read that the first thing that came up in my mind was welding. But this is also are really good solution.

  5. Freek van de rijzen says:

    The effort you went through to fix this table saw is admirable though understandable. It’s always gives a certain satisfaction to repair a good piece of equipment. Especially when the malfunctioning part is easy to mend. Though in your case easy might not be the correct word. It took you some time to replace the trunnions. Like Roy, I wondered if welding the old trunnions would not have been an easier and more durable solution. But after doing some research I realized that welding or soldering pot metal is not quite that easy. The manufacturer probably should have used regular iron or steel to prevent malfunctions like this. That’s not important however. What matters is that you found an easy solution and saved this band saw a trip to the junk yard. Happy sawing!

    Kind regards,

    Freek van de Rijzen

  6. Emma Treurniet says:

    I like it when I see that someone takes effort to renovate an old bandsaw. A lot of people don’t take they effort to renovate and they just buy a new one. Most of the thing that an old they have relative a lot of quality in practice. I think a lot of people can follow your example to fix more machines. When you a renovate old products, you have to work with the stuff you already have and when you save rest materials you can use it for project like this. Have fun with you renovated saw

    Emma

  7. Jess Bos says:

    I admire that you did not choose to let the bandsaw go to waist. I personally think that tools and machines should get a second chance at life. Understandably only if this is safe for the machine and for you. Thank you for using material that everyone commonly has lying around. Quite often I have come across the problem where I need to fix or build something, but I do not have the materials that are required. Did this project require very much precision? I can imagine because these parts are under a table that the did not need to look pretty.

  8. aldayr says:

    I admire your dedication and the effort you put into repairing the machine you got from your friend, ofcourse buying a new machine would be way faster but also more expensive i salute you for taking the time and effort to find another solution to fix your machine, you showed us that even tho you don’t have to right parts or something is wrong there is always a way to fix something if you just use your imagination and skills. And i also like the fact that you put in what went wrong so others can learn from your “Mistake” Great job.

    Kind regards

    Aldayr Jansen

  9. Bart Buijze says:

    Hello,
    I am a student from Rotterdam in the Netherlands. Our English teacher gave us the assignment to read your blog and comment on it.
    The way you think about making the bandsaw from your friend to get it worked in the right way is good and saving a lot of money. But what if there ever happened something with you loose your finger or something, does your insurance give you than money or anything? Because you fixed the bandsaw by your self with wood. If I should do something like that I would buy a new one.
    Greetings from the Netherlands,
    Bart.

  10. Quinten van Zoelen says:

    You,ve done an extrodinary job with fixing the bandsaw with all the bumps ,ve come across. I very injoyed rearding this blog, because it’s nice to see someone dedicated to fix something and then see the final result work. The bandsaw also looks really nice and in good condition. I guess it took a long time getting it right. You couldn’t look up the parts you need fort his machine, because they stopt manufactured this machine. I also thought that you explained it very clearly in your blog it was easy to follow. I hope that saw will continue to help you properly with your saw work.

    Kind regards
    Quinten van Zoelen

  11. Linde says:

    I think it is fantastic that you would take the time to repair an old machine. Not everyone has the dedication to repair something. I also think that sharing your story can be really helpful for others. It shows people that you do not always have to throw away everything when it doesn’t work fully, there is always a way to repair it. Buying does not always have to be the number one solution.
    When having repaired something yourself it gives you a certain feeling of proudness, which you should feel when it works again. I think you feel great about it yourself as well that you repaired it even though it took some time.

    Kind regards,

    Linde

  12. Sarah says:

    I think it’s quite clever that you decided to just make the broken parts out of wood. Sure, you lose a bit of the function, not being able to tilt the table, but you clearly considered whether you really needed that or not. If it’s a function you never actually use, it doesn’t really matter if it’s no longer an option. Wood is of course less durable than metal, but without the tilting I assume the trunnions take a lot less wear and tear. It sounds like it would take a bit of fiddling to get the table perfectly level, but once you’ve managed that, this seems like a perfect way to solve your problem. It would have been a shame to have to toss out the machine for this.

  13. eef says:

    I think it is fantastic that you would take the time to repair such an old machine like this one. Not everyone has the dedication to repair something especially this old and damaged. I think it’s really clever that you have decided to just make the broken parts out of wood. Clearly considered whether you really need it, especially if it wouldn’t have been a function you normally use.

    It looks like it took you a while to get it all right. And I think it must feel great to see that you repaired it even though it took quite some time.

    Kind regards,
    Eef

  14. Bart Bochanen says:

    I’m Bart and I am a 20 year old student as woodworker in the Netherlands.
    I like to see that you are saving money by replacing your missing machine parts by making them of wood instead off buying them. It’s a great gift when you get an old band saw from a friend. For me and I think for you also it’s a very nice challenge to test your skills in woodworking. In exchange you get a nice working band saw and it only cost you a bit of time and maybe the wood itself. I think it’s better than buying a new one.
    I hope you’ll be able to make some beautiful projects with it.
    Greetings from the Netherlands,
    Bart Bochanen

  15. kimberly says:

    It is really nice how you fix the bandsaw with wood. I admire the way you make it very much! You really inspired me to think about maybe simple solutions you can make with wood and save money. It is a nice way to give things a new life. Ofcourse it cost really a lot of money to just buy a new bandsaw but don’t you think it is a little bit risky to repair a machine like that yourself. It is such a power full machine, i wouldn’t take the risk. Bt after all your text and photo’s where really clear and easy to understand what you where trying to say.

    • Risky? Not really. I’ve done mechanical repairs on other machines before, including my own cars, so I’m pretty confident in what kinds of repairs I can make. I also have a pretty good sense of when I’m in over my head. In this case, the repair was virtually risk-free. The worst that might have happened is that the bandsaw would not have been usable–which is the condition I received it in anyway.

  16. Stéphane says:

    I really enjoyed your article and mindset on this machine,
    I don’t think enough people appreciate older machines or machines in general.
    It is not that difficult to fix a broken machine with a little help and the right tools.
    some machines will last a very long time with the right maintenance.
    I do wonder how the maple will hold up after a while,
    Do you think it will need to be replaced after a few years or less?
    And if necessary do you think you will switch to a different material?

    Kind regards,
    Stéphane

    • As long as the maple stays dry, it should last for many years. I selected the wood for its hardness, as well as for its relative stability. Because it’s not a moving part, it shouldn’t wear out over the working life of this saw.

  17. Barney says:

    I too have this 14″ steel city band saw and both trunnions broke. I am not sure why people are saying they went out of business…I just got a quote from the manufacturer…they seem to be canadian..for 70$ for the pair. Bit pricey…I might try to build your ingenuous fix.

    best regards.

    Check out http://www.steelcitymachines.ca

  18. Dale Chellis says:

    Both trunnions on my Steel City saw broke this afternoon – I did not realize that this critical component was made of pot metal until I disassembled the top – maybe that is why Steel City is out of business in the States!. I am in the process of using the “wood trunnion” solution as well. In the meantime, I recalled that when I purchased the saw, I was told that the guys that designed the Steel City line were ex-Delta employees – I found the Delta-comparable saw on line – the trunnions in the parts diagram look exactly like the Steel City ones – and have ordered two each of part number 426020950002S (Trunnions) from ereplacementparts.com. I am hoping that these parts will work! Will update this note when I get the parts in.

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