Bandsaw blade drift myths

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DLB
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Re: Bandsaw blade drift myths

Post by DLB »

In one of Scott M's videos he used a Cater F.A.S.T. fence alignment tool. This tool attaches magnetically to the body of the blade and has a machined clearance for the teeth. It establishes an angle, the fence is set to the angle. It is much the same as determining the angle be freehand cutting a straight line and setting the fence to that angle. I didn't think Scott really established that both angles are the same. But he did demo satisfactory results using the tool. And the tool does seem to prove that typically the bandsaw blade body will not run true. Suggesting that the angle we call blade drift is in fact the angle of the body of the blade to the table. And conflicting with other hypotheses of the cause.

Relieving stress in lumber is different. But it's different whether I'm using a fence or a sled or a bandsaw or a table saw. Or anything else, in my experience. Cutting thin veneer-like strips is not the approach I'd take if I wanted to illustrate this problem.

- David
DLB
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Re: Bandsaw blade drift myths

Post by DLB »

If you have the Aluminum table BS you can emulate this Carter F.A.S.T. alignment tool with one or two small magnets and a light steel straightedge. Put the magnet(s) on the body of the blade making sure to stay clear of the teeth and the straightedge on the magnet(s). The magnet thickness is more than enough to create the clearance between straightedge and teeth. When I tried this, sample of one, I came very close to the angle my fence was already offset using the free-hand cutting method.

- David
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JPG
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Re: Bandsaw blade drift myths

Post by JPG »

Now WHY is the blade 'skewed'?
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algale
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Re: Bandsaw blade drift myths

Post by algale »

JPG wrote: Wed Jan 05, 2022 1:54 pm Now WHY is the blade 'skewed'?
Maybe the table is skewed?
Gale's Law: The bigger the woodworking project, the less the mistakes show in any photo taken far enough away to show the entire project!

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JPG
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Re: Bandsaw blade drift myths

Post by JPG »

Good Answer!

Whatsa good reference?
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
DLB
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Re: Bandsaw blade drift myths

Post by DLB »

After reviewing the manual it appears to me that the deviation between the blade body and table (skew, above) should be corrected by table alignment. IIUC that suggests that an alignment error indicated by the Carter F.A.S.T. (or my emulation of it) should be corrected by table alignment rather than by offsetting the fence. I'll be trying that soon.

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JPG
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Re: Bandsaw blade drift myths

Post by JPG »

I agree, but think that fence adjustment is quicker/easier than table alignment to the blade which may vary blade to blade.

With the flat (tapered) periphery of the SS wheels, that variation between blades may be minimal.

If so then the blade becomes the good reference. Not a precise one due to the narrowness of the blade.
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╟JPG ╢
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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edflorence
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Re: Bandsaw blade drift myths

Post by edflorence »

JPG wrote: Wed Jan 05, 2022 12:31 pm
I agree a new blade(if near perfect) should not have significant drift.
That is pretty much the same conclusion that Jack Turley comes to in an article he wrote for Mark Duginske's book called "The Bandsaw Handbook." Mr. Turley mentions a number of factors that might contribute to drift, such as blade tension, bearing placement, feed rate, blade thickness, number of teeth per inch and the set of the teeth, but at the end of the day he says that drift likely indicates the blade is wearing out.
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