Please help me with Band Saw Setup - older Delta 20" 28-640 / 28-641

[Brent McDonald]

I have an affection/sickness for OLDER equipment and tend to purchase most of my woodworking gear on Craigslist and then spend a bit of time going through it to get it tuned and working nice.

About a year ago I purchased a big Delta 20" Band saw model 28-641 and I need some help with this monster. I got the 600 lbs beast for $500 delivered and went to work on it. I replaced the 3hp 3-phase motor with a 5hp single phase. I replaced the tires with urethane tires, added a LED light on top and a magnetic switch. I've spent hours trying to tune it but don't have the expertise.
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There is a lot of CONFLICTING INFO out there and I'm confused. Please help. I've read numerous forums and watched several Youtube videos of "experts" explaining how to set up a bandsaw.

• Some people say the GULLETS of the blade should be centered on the top tire and others say the blade should be centered on the top tire....which moves the gullets forward of center. Which is it? I went with the Gullets as close to center as possible in accord with Alex Snodgrass' video. Any thoughts on that?

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• Many people say the top and bottom wheels need to be coplanar including Mark Duginske says in his book about bandsaws. However Alex Snodgrass another bandsaw guru who works for Carter says that they do NOT need to be coplanar and work better if they aren't. The Delta manual doesn't even mention the issue and I can't find anything on Delta's recommendation via Google. I deduced that my Delta saw is probably an older cousin to a Jet model JWBS-20i as they take the same blade length. The Jet manual makes no mention of Coplanar either. Grizzly has even made videos indicating how to shim their bandsaws to be "COPLANAR". My top wheel is NOT coplaner with the bottom wheel. In fact I'd say it's sits at least a quarter of an inch behind the bottom wheel when facing the working side of the saw. The huge cast iron wheels have a bolt and washer. When I remove that bolt and the split ring behind the washer the wheel doesn't seem to budge from it's place. How the heck do I get it off to "shim" it? There seems to be a mechanism behind the wheel assembly that MIGHT allow adjustment but it appears to be tack welded in place. Any thoughts on that?

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• Some people say you adjust your table to be square with the blade by loosening bolts that affix the table to the trunion and wiggle the table to square the miter slot with the blade and the fence with the miter slot. Others say just loosen the fence attachment bolts and adjust the fence to the blade and then square the miter gauge to the fence but this would render the miter slot useless for other jigs wouldn't it?

• I have the blade at 90* to the table from the left or right but I can't get the blade perfectly 90* when placing a square against the BACK of the blade. Does this matter?

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Thanks in advance for the Wisdom, experience and help you will share with me.

[Phillip Mitchell]

Where's the popcorn symbol when you need it?

I'm excited to see some answer regarding these specific questions as well. Sorry, but I don't have much of anything definitive to say on the matter as I'm fairly new to setting up bandsaws as well and all the same thoughts have rolled around in my head.

[Matt Day]

You won’t find concrete answers. There are basically two camps and you need to figure out which one to go with. I’d pick Van’s camp. He’ll hopefully reply to your thread.

[John TenEyck]

My Grizzly G0636X manual says the wheels should be coplaner and the blade should be centered on the top wheel. The fact that the back of your blade isn't parallel with the square proves the wheels aren't coplaner. That matters for sure as you raise/lower the upper blade guides; as the blade now is the guides will move closer to the teeth as you raise them and closer to the back as you lower them. That's rather a big deal when you get to using narrow blades. And if you want to use your BS to cut shoulders on tenons, or anything similar, the cut won't be square top to bottom. Also a rather big deal. Despite that I would leave the wheels where they are for now if they are at least in parallel planes. If they aren't then I would figure out how get them coplaner, or really close to it.

Snodgrass's recommendation to center the back of the gullet on the upper wheel works OK for narrow blades, but it won't work for wide ones. Think about centering the back of the gullet of a 1-1/4" or wider blade on a 2" wide wheel. I center the blade on both my larger 17" Grizzly and on my 14" Delta and they both run fine.

Once you get the blade centered and running there, then you can adjust the table so the miter slot is parallel with the blade. As you said, the miter slot will be useless if it's not parallel with the blade. Whoever started the urban legend to adjust your fence for drift should be hanged. If your fence isn't parallel with the miter slot, adjust it so it is. If you have a sharp blade with equal set on both sides rip and resaw cuts should be parallel with the fence with no tendency to push the wood into it nor pull it away.

John

[Jim Becker]

If the tires are crowned, I'd center the band on the wheel and that setup should be pretty consistent for most blade widths you choose to use and it keeps the teeth from hard contact with the tire unless they are pretty narrow bands.

[Brent McDonald]

Thank you so much for the great insight John. I visited Grizzly's website and saw that your machine is fairly similar to mine. I figured it came out of the same factory so I viewed the 21" model G0531B which is even more similar to my 20" delta. I downloaded the manual and followed the instructions on page 46 & 47.

I cut a gauge board and it turns out my top wheel was almost 5/8" an inch behind the bottom wheel. Based on videos I had watched on Youtube over the weeks I've been wrestling with this, I was under the impression that I would have to remove the UPPER wheel and shim it to bring the two into the same plane. I didn't see how I could possibly move the upper wheel that much because it would bind on the blade guard assembly. Thankfully this was NOT how you adjust this saw. Fortunately with these larger Band Saws the "Adjustment Hub" allows you to move the LOWER wheel in or out. I started fiddling with it and the saw darn near fell into proper alignment. It was surprisingly EASY. I'm thinking that when the saw was traveling to my house via trailer it had gotten jarred out of proper position and that once the tension on hub bolts was loosened a little it returned to it's natural home alignment.

Next I aligned the fence to the miter slot and then adjusted the table to the blade using some scrap plywood to make alignment cuts.

Then I grabbed a 9" round piece of mesquite and sliced of a piece that is 5/64" thick as you an see from the pictures below.

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John, I couldn't have done this without you. Thank you for generously sharing a little bit of your time and expertise with me.

Warmly yours,
Brent McDonald

My Grizzly G0636X manual says the wheels should be coplaner and the blade should be centered on the top wheel. The fact that the back of your blade isn't parallel with the square proves the wheels aren't coplaner. That matters for sure as you raise/lower the upper blade guides; as the blade now is the guides will move closer to the teeth as you raise them and closer to the back as you lower them. That's rather a big deal when you get to using narrow blades. And if you want to use your BS to cut shoulders on tenons, or anything similar, the cut won't be square top to bottom. Also a rather big deal. Despite that I would leave the wheels where they are for now if they are at least in parallel planes. If they aren't then I would figure out how get them coplaner, or really close to it.

Snodgrass's recommendation to center the back of the gullet on the upper wheel works OK for narrow blades, but it won't work for wide ones. Think about centering the back of the gullet of a 1-1/4" or wider blade on a 2" wide wheel. I center the blade on both my larger 17" Grizzly and on my 14" Delta and they both run fine.

Once you get the blade centered and running there, then you can adjust the table so the miter slot is parallel with the blade. As you said, the miter slot will be useless if it's not parallel with the blade. Whoever started the urban legend to adjust your fence for drift should be hanged. If your fence isn't parallel with the miter slot, adjust it so it is. If you have a sharp blade with equal set on both sides rip and resaw cuts should be parallel with the fence with no tendency to push the wood into it nor pull it away.

John

[Doug Garson]

Once you get the blade centered and running there, then you can adjust the table so the miter slot is parallel with the blade. As you said, the miter slot will be useless if it's not parallel with the blade. Whoever started the urban legend to adjust your fence for drift should be hanged. If your fence isn't parallel with the miter slot, adjust it so it is. If you have a sharp blade with equal set on both sides rip and resaw cuts should be parallel with the fence with no tendency to push the wood into it nor pull it away.

John

What method do you use to adjust the mitre slot and fence to be parallel to a 1/4" band saw blade? I understand how you do it with a 10" table saw blade by measuring at the front and back but when the blade is only 1/4" wide? I agree that a blade with equal set on both sides will cut straight but the reality is unless you use the blade for straight cuts only it will eventually develop drift. How do you handle that? And oh, I would consider hanging pretty severe just because you disagree with someone. How about 50 lashes with a wet noodle?

[Brent McDonald]

What method do you use to adjust the mitre slot and fence to be parallel to a 1/4" band saw blade? I understand how you do it with a 10" table saw blade by measuring at the front and back but when the blade is only 1/4" wide? I agree that a blade with equal set on both sides will cut straight but the reality is unless you use the blade for straight cuts only it will eventually develop drift. How do you handle that? And oh, I would consider hanging pretty severe just because you disagree with someone. How about 50 lashes with a wet noodle?

Doug,

There may be better ways but my approach was this:

1. Square the fence to the miter slot
2. take a squared up piece of plywood that is 2-3" wide and 24" long and draw a line down the middle.
3. make a careful free-hand cut strait down the line until you are the halfway point in the plywood and shut off the saw. This left the 24" piece of plywood that is parallel to the blade centered nicely on your saw table.
4. Adjust the table so that the fence fence is parallel to the plywood. My saw had bolts under the trunion that could be loosened and to allow for this adjustment

I had to do this two times to get it locked down precisely. The first attempt got me pretty close and the run allowed me to make a little more fine adjustment.

I see that Carter sells a aluminum stick with a magnet on it for this purpose for about $55 - CARTER F-A-S-T Fence Alignment Tool

Warm Regards,
Brent

[John TenEyck]

Brent, I'm happy you were able to get your saw dialed in; perseverance often pays off. I think your story precisely describes why you should check to see if the wheels are coplaner, or close to it, before going down blind alleys. I wish Mr. Snodgrass would modify his talk to reflect that saws don't always arrive with the wheels in the same orientation they left the factory, even more saw for used saws, and that if a saw won't cut right to check the alignment of the wheels.

So where did the wheels end up once you had them adjusted to your satisfaction? And how does the back of the blade now sit relative to being square to the table?

Enjoy your "new" saw.

John

[John TenEyck]

You only have to square the table to the blade once, so it's easiest to do it with a wide blade. On my little 14" Delta I put a 1/2" x 3 tpi blade on it, the widest I have for it, then lay a straight edge along the side of the blade. Then loosen the trunnion bolts and adjust the table until the miter slot is parallel with the straight edge. Tighten the bolts and then make a test cut like Brent described. A couple of fine adjustments might be required from there but it doesn't take long. And once you have it adjusted it should always cut straight regardless of what blade you put on as long as the blade sits on the center of the upper wheel. If you put on a new blade and it doesn't cut straight, then adjust it forward/backward on the upper wheel until it does. If nothing makes it cut straight, I would suspect the there is something wrong with the blade; not all new blades are perfect.

If you use your bandsaw for cutting curves then you should accept that the blade is likely to get dull on one side before the other. The simple answer to your question is that you should not expect it to cut straight after it's been used for cutting curves and to change it for a blade only used for ripping/resawing when you need to do that. That's one reason why I have two bandsaws, with the big one used exclusively for ripping/resawing in milled stock.

Nope, whoever started the whole adjust your fence for drift nonsense disserves more severe punishment than 50 lashes with a wet noodle. Ok, maybe no hanging, but certainly at least a day in the stocks on the public common.

John

[Doug Garson]

So essentially you are setting the fence and mitre slot to be parallel to the direction the blade cuts not necessarily to the blade itself unless the blade has no drift. I see an advantage to your method if you use the mitre slot (I rarely do except when I use my log sawing sled) otherwise you are just using a different method to get your fence parallel to the cut line ie you are adjusting your fence for drift by adjusting the whole table.

[John TenEyck]

I don't see it as tomatoes vs. tomatoes as you are suggesting. If the blade is centered on the upper wheel and the table is made parallel with the blade there should be no drift. There still could be if the blade has unequal set on one side or is duller on one side, however, but assuming the blade is good there shouldn't be. That allows you to set the fence parallel with the miter slot and be able to rip/resaw without drift compensation and also be able to use the miter gage with no tendency to push/pull the work as you cut it. It also allows you to change blades w/o having to worry about drift. This is how BS's were designed to be used, the same as your TS.

Adjusting the fence for drift is what you do, temporarily, when your blade gets dull on one side and you don't have another to replace it.

John

[Jimmy Smith]

Hello, Most of those old deltas had a different type of tire than most bandsaws. There is a groove in the wheel for a tire that has o-ring looking piece on the inside of the tire that makes the tire crown when it is put on the wheel.

[Wally Turbeville]

Thank you for this thread, you can only guess how much I have struggled with my Delta 28-303F. I was at the point of trying to get my blade centered on the top wheel when I read this. Does moving the blade forward on the wheel move the cut left ?

[John TenEyck]

Thank you for this thread, you can only guess how much I have struggled with my Delta 28-303F. I was at the point of trying to get my blade centered on the top wheel when I read this. Does moving the blade forward on the wheel move the cut left ?

Yes, it should.

John