Bandsaw question

[charlese]

Although not an expert on bandsaws, my SS bandsaw always runs blades, regardless of size to the back of the upper wheel. Has done so since new. I'm still using the original black rubber tires - going on for 15 years.

The upper wheel should be canted! You said ---- "I held a straightedge against the lower wheel, and the straightedge contacts the lower edge of the upper wheel, but there is about a 1/4" gap at the top edge."---

This leaves me to think the cant of the upper wheel is not as much as it should be. A straight edge held across the UPPER wheel should fall in front of the lower wheel by 1/4 to 3/8".

Since the upper tire is loose but does not come off the wheel when the blade is thrown, makes me suspicious the "auto track rolling bearing bracket" is bent or possibly not tightened. Also check the wheel arm and axle to see if it is straight.

Here you will find the parts list and exploded diagram of the bandsaw. http://www.shopsmith.com/service/bandsaw/index.htm

Edit; fixed spelling errors

[JPG]

Chuck said what was overdue from the beginning of this thread.

I would add that the rear guide bearings may be 'missing'. That would cause the blade to go beyond the edge of the tire. Bent bracket IS possible, though I think unlikely unless bent (well)intentionally.

900(C) rpm would be an upper limit for small blades.

1/2" tension is SS's recommendation for 5/8" blades.

Sorry I missed the start of this thread.

[charlese]

After thinking about your situation a while, it seems that all you need to do is to cant the upper wheel properly. See post #11.

There are two methods I know of to do this.
1) One is to grasp the lower edge of the upper wheel in one hand and the upper edge in the other. Then push in the upper edge while pulling out the lower edge. The purpose is to bend the arm a little bit. The arm holding the axle evidently gets bent downward when tension is left on a saw blade for a long time while sitting unused.

2) Another method recommended by Bill Mayo, that is safer and prevents a bent wheel is to fit a pipe over the axle and use the pipe to bend the axle up.

I have never had a problem with a bent wheel, using the first method, but some have.

Also don't forget to grease (pack) the needle bearing in the upper wheel.

[magasin11]

I was running on A but still throwing tires. I went inside and found the lower pulley was stuck. I could not find anywhere where it was stated how the pulleys should be at the slowest speed. So here is what I found. At the slowest speed the lower pulley should be fully expanded and the upper pulley should be fully compressed. Now I have to find and allen wrench to reset my speed dial which is off.

[rcplaneguy]

So the bandsaw was running too fast.....that explains throwing the tires! Mystery solved.

[JPG]

I will pre-empt BEEG here.

Have ya been lubing it recently?


A lesson fer us all!!!;)

[charlese]

Let me add my favorite way to lube the lower sheaves.--
Put the headstock in drill press position - Remove the belt cover and secure it to the tie bar. - Drip some light oil onto the motor sheave shaft and allow it to run down along the shaft. With you hands pull the floating sheave out several times. Make sure the oil has covered the entire motor shaft beneath the floating sheave's sliding tube and the floating sheave moves smoothly. Do not depend entirely on oiling into that little hole beneath the spring.

It may be surprising to some that stickyness of the floating sheave can cause strain on the other end of the control stuff. Speed control, pork chop and little retaning loop at the end of the control sheave can all become victims of failing to properly lubricate the fan and floating sheaves.

[teacherman]

Hope I'm not hijacking the thread, but is there a rule of thumb on blade tightness? I think the recommended marks seem a bit tight, but I am new to bandsawing. Is there a recommended "tone" when you twang the blade?

Seems to me that is a critical part of tracking and machine longevity.

[JPG]

Hope I'm not hijacking the thread, but is there a rule of thumb on blade tightness? I think the recommended marks seem a bit tight, but I am new to bandsawing. Is there a recommended "tone" when you twang the blade?

Seems to me that is a critical part of tracking and machine longevity.

Twanging is fer folks who do not have an accurate tensioning spring that is unaffected by tracking adjustments, belt length etc.

"WE" do not have those problems.

If you think the setting is too tight, reduce it. Then performance is to be observed. As long as there is no slipping, all should be well.

You do not want the blade teeth shredding the tires.

[teacherman]

Twanging is fer folks who do not have an accurate tensioning spring that is unaffected by tracking adjustments, belt length etc.

"WE" do not have those problems.

If you think the setting is too tight, reduce it. Then performance is to be observed. As long as there is no slipping, all should be well.

You do not want the blade teeth shredding the tires.

I'm thinking I may need to follow the guidelines, because a looser blade can bend a bit during resawing. I just don't want to bind up and wear the bearings esp. since the shaft would wear as well.