Delta Band Saw - Blade deflection

[Albert]

Esteemed Colleagues,

I have a delta band saw that's relatively new. Since I've been working on building kitchen cabinets for the last several months, the band saw is rarely used.

Yesterday, I needed to resaw a cherry board (3/4" x 3 inches wide) x 4 feet long. Just needed to split the board in two halves (front and back). This required positioning the board on its side, up against the fence.

Using a test board (thank goodness), I noticed that when I started sawing the board, the cut was not straight. The blade seemed to deflect outward - yielding a crooked cut. Not sure of the cause...

Your expertise and commentary is greatly appreciated.

Thank you.

-Albert

[nospambob]

[Rumpty]

Your fence isn't aligned with the track of the blade.

Take a piece of flat wood with a jointed edge, draw a parallel line to the edge, then saw this board on the line freehand without a fence. You will have to adjust the board to compensate to the blades track. Once the track is established, stop sawing, stop the saw and then adjust the fence to the jointed edge of the board. Remove the test piece and try a few cuts with scrap.

[Bob S.]

What Rumpty said but I'll add....

If you're using a standard blade then your blade tension may not be high enough. Haven't seen a scale yet on a Jet or Delta BS that is anywhere near accurate. Best advice, keep adding tension and test again. I have a 1/4" blade I use once in awhile and the tension is double what the scale indicates for a 1/4" blade.

If it's a low-tension blade, like a Suffolk, measure the horizontal deflection as per their instructions. For a 3/4" wide blade, I believe they say 1/2" deflection max at the center point but I don't have the instructions here with me.

Also a 3tpi or a skip-tooth blade is recommended for resawing. More teeth than that and the blade will wander since the gullets get filled and the waste gets hot and gummy and it forces the blade to deflect (bow out). Also, slow down so the blade has time to clear the gullets and stay cooler if you don't have a resaw blade.

Bob S.

[Steve Knight]

I don't think it is the blade so much as the saw. I have only had to change my fence a few times with several brands/makes of blades. if I use the same blade it never changes.

[David Binkowski]

I spent the first half of this week resawing a 7 foot piece of cherry with my Dohzuki. You don't get much drift when resawing with a Dohzuki, but it takes quite a long time...

[Anonymous]

Albert,

All bandsaws tend to have some deflection, however there are exceptions. First tune your BS. If you don't already have Mark Duginske's book get it and follow his directions on tuning your BS. If you are using the stock blade you'll have to adjust the fence for drift. Most times the blade drifts because of improperly set teeth.

I've been using Timberwolf blades from Suffolk Machinery and I set the fence parallel to the blade and I have no drift. They do make a quality product with properly set teeth.

Layne

Usual disclaimers apply.

[Bob G]

I agree on tuning your Band saw...

BUT I also use Timberwolf blades AND until some other "super" blade comes along, that works better, They are the only blades I will use...

HOWEVER...I have to adjust for drift with each and every blade...and some require the fence to be at a very noticable angle... Which honestly does not bother me in the least...only takes a minute or two to adjsut the fence to the blade.

Bob GRiffiths

[nospambob]

[George]

I just gave up on the whole fence idea and use a pivot and scribe mark to set my feed angle. Allows me to clamp a pivot of appropriate size on the right, so I can use the clumsy hand to steady the piece up against the pivot, and my favored right hand to guide and feed.