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Why does the band saw not cut straight when using a fence. The cut keeps getting wider and wider. What is it about a bandsaw that causes this? How can you compensate?
thanks
thanks
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The drift you are experiencing could be any of a hundred different alignment/adjustment scenarios, as well as blade selection, feed rate, poor design, and other things. Each make and model of saw adjusts a little differently from other types. You would do well to contact the customer service people at the company who made your saw, and let them help you identify the problem and approach a solution. -
It's the nature of the beast. The blades is not rigid. Band saw fences are usually adjustable. You need to find the feed angle that the blade wants and adjust the angle of the fence parallel to that line.
I draw a line down the edge of a board and feed it into the blade free hand. After a couple of inches, turn off the saw, leaving the board at the angle which results in a straight cut and align the fence to it. This should result in a fairly straight cut.
You should also have the rollers and blocks adjusted to minimize the twisting of the blade.
Feed rate, blade size and design, and correct tuning of the guides all have impact on the amount of deflection,A man without a shillelagh, is a man without an expidient.Comment
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there can be many reasons, usually some or all come into play:
1. Tooth set, many , esp. cheaper blades, tend to have the teeth stamped which imparts a set to the right or left (depends on which side they were stamped from), makes the blade drift
2. wheel has a crown, if the wheel alignment is not perfectly set so that the blade rides exactly on the top of the crown then the blade will be angled slightly to the right or left (think about the side of the wheel, if the blade is forward or rearward of the crown then it will tilt inward or outward, respectively)
3. Tension
4. angle in the blade guides not perfectly aligned
5. stresses in the wood/wood grain
6. maybe the upper blade guide set too high, even if lowered all the way and the guides are square to the fence, the blade will flex some due to the space between the guides and the wood
Loring in Katy, TX USA
If your only tool is a hammer, you tend to treat all problems as if they were nails.
BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questionsComment
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In addition to what Warren, Cracker and Loring said, read this:
http://www.woodcraft.com/articles.aspx?articleid=223
make sure the blade is tracking in the center of the top tire, and that the blade tension is good, do not go by the tension indicator on the BSComment
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Maybe I've just been lucky but I've found with my saw, if I adjust everything properly, I don't have "drift". I read in one of the WW magazines (don't remember which one) that if the blade is properly tensioned and the tracking is set so that the blade runs on the middle of the wheel, drift won't be a problem and I've found that to be true in my case. However I may just be lucky in that the blade will track in the middle of the wheel, on my first bandsaw(bench top model) the blade didn't always track in the middle of the wheel. That might have been because of the quality of the saw, or because I didn't know how to make it track in the middle of the wheel. In any case since I've upgraded to a better saw, and if I take the time to make sure the tension is correct and that the blade is tracking in the middle of the wheel, I have good luck resawing with a square fence.
DonHoDonComment
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Afternnon Oreo...
I will re-hash what has been said already and suggest you purchase the Band Saw book by Lonnie Bird or the book by Mark Duginske to get a better understanding or the most "finicky" machine in your shop but one of the "sweetest" when all is right.
Sharp blade.. correct TPI selection.. tuned wheels and bearings properly set.. correct feed speed.. and last and probably the most important for re-saw is "beam strenght" (having springs that are capable of tensioning a given width of blade).
I used a small Jet 12" for years and got OK results using a home-made fence and a Wood-slicer 1/2" blade. It would only do 5 1/2" and that is not a real challenge unless really hard wood. I purchased a Steel City 18" BS last fall and use a 3/4" Woodslicer. No adjusting the fence for drift as their is no drift (the SC delivers all the above components mentioned) to the point I mainly use a "point fence" ( a single point that the stock rides at the blade to steady it) and re-saw all but the most delicate veneer free-hand with the "point".
Regards...Comment
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Blade drift can usually be corrected by adjusting the tracking of the blade on the upper wheel. I would be inclined to try that first, before working on the other adjustments.Comment
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The first thing I'd do is get a good blade. Setting up the saw properly with a cheap blade will just lead to frustration. I was "enlightnened" when I bought my first Timberwolf. A lot of guys here use the Woodslicer and are verypleased with that.
ToddComment
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ok thanks. I just saw a woodworking tv show on DIY network. Mark something?
He had a nice pro bandsaw and what he did was run a trial piece through then adjust the fence to the same angle of the resulting cut to compensate for the wander. I notice the after market fence on my bandsaw actually has that adjustment so Ill give that a try.
thanks again for the tips.Comment
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Loring in Katy, TX USA
If your only tool is a hammer, you tend to treat all problems as if they were nails.
BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questionsComment
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I assumed that. Its infrequent when I resaw so not a problem if it works. Doesnt sound like anything else I can do.Comment
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As my tires are wearing I have started to get a little drift, and if I test cut with sufficiently thick stock of a hardwood, I can get my fence tuned in well enough for resawing. I did see some issues between purple heart and say, maple, but overall it's not a bad technique.
btw, David Marks, wood works, the guy in the picture here with me.Keith Z. Leonard
Go Steelers!Comment
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