Ol' Delta bandsaw maintenance

[Steve Tiedman]

After a good 35 years in home shop service, about 28 of those with me, my 14" Delta bandsaw (with riser block and 1hp Leeson motor) needed a little love. It's been doing some shimmy-shaking and I thought at a minimum a new belt was in order. I pulled off the belt cover, turned it on, and found the shimmy. The original 6" soft cast metal saw pulley was swingin' its hips like Elvis. I tracked down a new steel pulley locally (pulleys are a dying species in brand name hardware stores, and forget "home improvement" stores) and installed it today. Even the new pulley, although a magnitude of order better than the stocker, needed a single thickness of pop can aluminum to make a near-perfect slip fit on the shaft. Made the pulleys co-planer, installed the new belt, and now it runs ram rod straight again- Elvis has left the building.

I'd previously bought some new bits from Iturra a couple years ago for blade tension, but with the new pulley hopefully we're good for another few decades. Moral of the story- check over your machines on occasion, including all those bits you never pay attention to.

 

[Phil Hamel]

Great write up and pics! Hopefully will give you years more use to play!

 

[John K Jordan]

Made the pulleys co-planer, installed the new belt, and now it runs ram rod straight again- Elvis has left the building.

Excellent fix! Hey, if you ever need fine adjustment the packages of shim stock are useful. I've also taken apart steel feeler gages and found the exact thickness I needed.

Those 14" Deltas with cast frames are great. I bought one new over 25 years ago and and used it until I got a new 18" Rikon. I cut many 100's of thick turning blanks from green wood for drying. Loved that saw. (I think mine hand a 3/4hp motor.)

I never had that a problem with the drive pulleys. I did replace the stock belt with a link belt.

Other things I did:

• Added a 6" riser block kit.
• Put it on a moble base with a foot lock.
• Installed a quick tension lever found on the discount table at Woodcraft. Detensioned after every use.
• Tried various guides, liked the phonelic Cool Blocks best.
• Aligned the table and fence properly - extremely important. There's an easy method.
• Replaced the tires once.
• After trying others, I mostly used Lennox 1/2"x3tpi blades. Zero problems cutting 12" thick wood, even osage orange and persimmon. Easily to resharpen.
• Bought a Starrett bandsaw tension gauge to set the tension correctly.

The little tension marks on the back of these saws (and clones) are not useful and cannot be trusted. Tension either too low and too high can be a problem Without a good way to check, the best advice was to set the tension for the next wider blade, e.g., for a 1/2" blade set it to the 3/4" mark.
.
After checking with the Starrett, I think those popularized methods to set tension such as the finger pressure bend and flutter test are not accurate. A tension gauge, bought or easily shop made, is the way to be sure. Too much tension can put unneded stress on the saw and cause premature wear. Not enough tension can cause vetical bowing in a thick cut and other problems. Have tension gauge, will travel. After checking other saws, I found that almost everyone used insufficient tension.

After some use, the stock tension block began to warp, a big problem. It was poorly made with weak cast metal. A stronger one from Itura did the trick
Also replaced the tension spring with a stronger spring from Itura.

Following advice from Duginski and Lonnie Bird, I adjusted the upper and lower wheels and made them coplaner under tension. This involved repositioning shim washers on the upper wheel and rechecking the alignment after tensioning. This improved the cut, especially when resawing which was tricky before.

I realize some people don't believe it's important to make the upper and lower wheels perfectly coplanar, but I do.

As an example of the improved resawing, I successfully resawed a long board for a friend that I would never have attempted before all the adjustments. He wanted a 2x12x12' Douglas Fir board resawn into four 1/2" boards of equal thickness. I built a tall fence, installed a new blade, magneticlaly clamped fingerboards to the table, hand-supported the back end, and fed the board slowly three times. He supported the board on the outfeed. The result was four thin 12" wide boards cut so well a very light skip-planing made them perfect down the 12' length. (He wanted to incase in the only post of many in his timber frame house that was not solid douglas fir.)

After building the new shop and installing the new Rikon the Delta sat unused until I traded it for an old accordion. That guy got a a real deal.

JKJ

 

[Steve Tiedman]

@John K Jordan, other than the mobile base, you've described most of my relationship with my saw. Actually, I had to replace the blade tension treaded rod and block (and spring, all Itura) because the threaded rod threads, a simple screw thread, actually wore away. Itura's replacement uses a stout acme thread and needs fewer twists to get to tension. And the new spring applies a lot more blade tension.

At times I wish for a larger saw, but in reality this saw has never left me shortchanged. I'll keep her running.

Ya know, for just a moment yesterday I thought of installing my new Leeson 1.5hp motor for my new belt grinder on the bandsaw, and sending the 1hp Leeson saw motor to the belt grinder. Not really needed though. Keeping good quality blades, that are sharp, does all I need it to do.

 

[John K Jordan]

for just a moment yesterday I thought of installing my new Leeson 1.5hp motor for my new belt grinder on the bandsaw, and sending the 1hp Leeson saw motor to the belt grinder. Not really needed though. Keeping good quality blades, that are sharp, does all I need it to do.

I was happy with 3/4 hp on my Delta - did everything I needed, any kind of wood wet or dry, up to 12" thick, with sharp blade of course. I typically resharpen bandsaw blades at least 3 times before replacing. I get my blades made to size from a certified Lennox blade shop at our local industrial gas supplier. I usually order a 100' coil of blade stock and have them weld up 8 blades.

When I teach bandsaw classes one thing people always want to know (in addition to how to sharpen) is how to fold up a blade and do it safely. Like anything, it's easy once you know how, even easier for a 1/2" wide blade. I show them first how to make a 3-loop coil (hold the bottom against the floor with one foot, grab the upper arc with both hands and "fold" both parts inward away from me), then make that into a much smaller 5-loop coil. I also make a 7-loop coil to show off just because I can - not as easy.

Working with the huge Woodmizer sawmill bandsaw blades is a different level. My blade guy can easily and safely coil and uncoil the huge blade. I can make a 3-loop coil without problem or danger but to uncoil I wimp out, undo the ties, then toss the blade onto a patch of soft grass. Twang! Even then, wear gloves and face protection.

JKJ

 

[Doug Rasmussen]

Even the new pulley, although a magnitude of order better than the stocker, needed a single thickness of pop can aluminum to make a near-perfect slip fit on the shaft. Made the pulleys co-planer, installed the new belt, and now it runs ram rod straight again- Elvis has left the building.

Steve, I agree, it never hurts to check machines for wobbling pulleys, etc.

But, you've got something seriously wrong with a pulley bore large enough to use a shim like that. The pulley should be a reasonably close fit on the shaft, sometimes close enough that you can't even easily push it on by hand.

Googling tells me a typical aluminum pop can has .003" to .005" thickness. A wild guess is the pulley is 16mm (.630") bore on a 5/8" (.625") shaft. Another possibility is the shaft is badly worn undersize from the former wobbling pulley's looseness, but the shaft doesn't appear to be worn though.

Whatever the issue that pulley OD is not going to be concentric to the shaft creating an out of balance situation where the soft shim will eventually wear repeating your original problem. And a wobbling steel pulley could damage the shaft.

 

[Hugh]

I was happy with 3/4 hp on my Delta - did everything I needed, any kind of wood wet or dry, up to 12" thick, with sharp blade of course. I typically resharpen bandsaw blades at least 3 times before replacing. I get my blades made to size from a certified Lennox blade shop at our local industrial gas supplier. I usually order a 100' coil of blade stock and have them weld up 8 blades.

When I teach bandsaw classes one thing people always want to know (in addition to how to sharpen) is how to fold up a blade and do it safely. Like anything, it's easy once you know how, even easier for a 1/2" wide blade. I show them first how to make a 3-loop coil (hold the bottom against the floor with one foot, grab the upper arc with both hands and "fold" both parts inward away from me), then make that into a much smaller 5-loop coil. I also make a 7-loop coil to show off just because I can - not as easy.

Working with the huge Woodmizer sawmill bandsaw blades is a different level. My blade guy can easily and safely coil and uncoil the huge blade. I can make a 3-loop coil without problem or danger but to uncoil I wimp out, undo the ties, then toss the blade onto a patch of soft grass. Twang! Even then, wear gloves and face protection.

JKJ

The last paragraph........I thought that was the proper way to unloop a bandsaw blade? Works for me.

 

[Steve Tiedman]

Steve, I agree, it never hurts to check machines for wobbling pulleys, etc.

But, you've got something seriously wrong with a pulley bore large enough to use a shim like that. The pulley should be a reasonably close fit on the shaft, sometimes close enough that you can't even easily push it on by hand.

Googling tells me a typical aluminum pop can has .003" to .005" thickness. A wild guess is the pulley is 16mm (.630") bore on a 5/8" (.625") shaft. Another possibility is the shaft is badly worn undersize from the former wobbling pulley's looseness, but the shaft doesn't appear to be worn though.

Whatever the issue that pulley OD is not going to be concentric to the shaft creating an out of balance situation where the soft shim will eventually wear repeating your original problem. And a wobbling steel pulley could damage the shaft.

Well, yeah, you're right. That shaft may be on its way to the scrap heap. It's a 3/4" shaft. I did not examine it closely, but a good glance as I was working the pulleys gave me the impression that the shaft was okay but possibly undersized by a thou or 2, or 3. I'll begin an inspection routine and act accordingly. Thanks for this.

 

[John K Jordan]

The last paragraph... [Woodmizer sawmill bandsaw blades...then toss the blade onto a patch of soft grass. Twang!].....I thought that was the proper way to unloop a bandsaw blade? Works for me.

I can coil and uncoil the little, thin 1/2" baby shop bandsaw blades with a thumb and one finger of each hand.

But the WoodMizer blades intimidate me. The steel is far thicker, strong spring, way less flexible. Teeth are more than 1" apart, long, wicked, take your face off in shreds. Where I buy blades the guy can handle them like paper ribbons, makes it look easy. I can coil an open blade with no problem, with gloves and safety glasses, but I feel like I need a knight's suite of armor to uncoil.

I should make a video sometime.

Maybe someone else here with a WoodMizer provide a tutorial.

 

[Webb Willmott]

I wonder if throwing the coiled blade in the grass would uncoil itself. Or standing in the grass and tie some string to the blade and throw it away from yourself like it was a yo-yo.

 

[John K Jordan]

I wonder if throwing the coiled blade in the grass would uncoil itself.

??
Uncoiling is the whole point of throwing it. (undo the twist ties first, of course)
The grass is to protect the teeth.
I would not want the blade to yo-yo back towards me.

Come visit and you can try all this yourself and saw a log or something. I saw in the winter.

I have no idea how they handle the HUGE bandsaw blades for a commercial sawmill. Must be 8-10" wide. I saw one being transported once and it filled the truck bed.

There's a commercial sawmill near here - it's well worth it to watch the entire operation, if they'll let you.
Before I got my own sawmill I'd take trailers with logs and they would buy them.

JKJ

 

[Doug Rasmussen]

Thinking about the classic 14" Delta bandsaw. They aren't all the same even if they are Delta 14". At some time pre-2000 Delta cheapened them a bit. The obvious way to tell is on the earlier/better ones is the shaft for adjusting the upper blade guide is hex not round with a groove. I don't recall all the details of the lessening quality, only that the man running the Delta reapir/parts store in Seattle told me newer was not better.