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Here is a fellow that uses a very well made (shop made) setup. He also uses the sacrificial board to keep the board properly stressed. It's really not sacrificial in that you should get many uses out of it. He also uses the "outside" cut, which is prefered for thin resawing.

http://www.borsonresaw.com/

This guy also uses compressed air on the exit side of his cut to cool the blade. How important is this? I have noticed that I can get great cuts on 8" redwood or walnut but when I switch to cocobolo or granadillo, it's a different story - the drift starts in and there is burning. I can see by this thread that blade tensioning might be some of the problem. How about cooling?

It's not air cooling. What you see there is a "mister" - a lubricant-air mist is sprayed on the blade to lubricate it - which will lead to less friccion, thus less heat.

Thanks Markus. You are right. I had it in my head that it was air because I was told by a machinist recently that they use compressed air to cool during drilling operations. I suppose that air could work as well. I'm just not sure how important a factor cooling is. According to him it is quite important.

It is water cooled. I guess it depends on how thin the cut. Me personally? I would not do that since the water has to go somewhere and I do not like the idea of water inside my bandsaw (or on my wood, Todd, leave that alone ). I bet you could do the same with compressed air through a venturi valve.

Mike

Edit: I should not have said Venturi...

On the mister.... That is a water soluble oil mix, generally mixed at 8oz. per gallon. They normally have a rust inhibitor in the oil. It is used for cooling, not lubrication. The real cooling effect would be from the one on top of the cut before it enters the workpiece. By the time it exits the cut, the water evaporates from heat and the oil that it encapsulated releases. By the time the oil releases the cooling has been finalized. There is no need to add a coolant on the bottom as the blade shoud be cool by the time it comes around the wheels to the mister on top. I use an airblast, through a mister setup on the bottom to clear the gullet, although I cut dry. A brush would also help. Not afraid of water on the machine or in the wood, more afraid of turning sawdust into gum, which would cause excessive heat. If you were going to just use coolant on the bottom or intermitently, you would be cooling a hot blade which would cause it to become brittle. The idea is to cool before it gets hot not after. Technically the proper way to lubricate is to flood.

When they moved me to the tool and die shop 40 years ago, the only thing they told me about a bandsaw was to " keep the wheels clean ". I use a 3" x 4" bar of aluminum and a couple of clamps for a fence. Basic rule on a blade is to have 2 to 3 teeth in the work at all times. I have used Lenox Matrix blades in a wavy 2-3 variable pitch for years. The only time I ever had any problems was after the Nicholson salesman decided that he would show me how to optimize my cutting. That lasted about 4 months. I have not had any problems cutting billets of Mahogany, Koa, Walnut, MadEbony, MadRose, Panama Rosewood, Holly, Spruce or Cedar on my vertical bandsaw. I think most people get into trouble when they try to feed either too fast or too slow, which will eat up the blade.

Tim

Just adding the opinion of "borsonresaw.com" :

Just curious, but is not mineral spirits flammable? Seems to me creating a mist could create a combustable mixture!

Mike

Edit: NEver mind, I believe he wipes his blade with that stuff...

Markus, I did not see that, but same thing I was talking about. Misters can be adjusted so that there is very little residual, and wiping the oil mix on the blade makes a lot more sense than atomizing a mixture.

Well, like said, I would not atomize mineral spirits near a band saw. Sparks from the thrust bearings could easily set it off. Borson uses water to cool and that mixture to wipe the blade down before and after a cut.

There should be no need for cooling when cutting wood. If you have heat build up then things are not right. Maybe too many teeth and there for not enough gullet to clear the waste, dull blade, improper drift angle, poorly set up saw, etc. If things are set up right you could wrap your lips around the blade and it won't be hot enough to burn. Ok, go for it, that last statement should be straight man fuel for the jokesters.
Link

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Cut to size.....Beat to fit.....Paint to match.

There should be no need for cooling when cutting wood. If you have heat build up then things are not right. Maybe too many teeth and there for not enough gullet to clear the waste, dull blade, improper drift angle, poorly set up saw, etc. If things are set up right you could wrap your lips around the blade and it won't be hot enough to burn. Ok, go for it, that last statement should be straight man fuel for the jokesters.
Link

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Cut to size.....Beat to fit.....Paint to match.

I suppose I could have put this one in the stupid mistake thread, but since it's a resawing thread, I'll put it in the stupid mistakes while resawing category.

I had just gotten my new 19" Grizzly bandsaw and had a brand new 1" Timberwolf blade. Well I wanted to make sure I took good care of my new $40 blade and I remembered reading on Suffolk Machinery's website about some lubrication for it. I remembered they said to spray a vegetable oil like lubricant like Pam on the blade while sawing and it would make it cut smoother and quieter.

So I got the Pam out, sprayed it on the blade and WHAM!!!!

The blade came off the wheels, ate part way through the lip on the lower door and killed about 15 teeth on the blade. Now I KNOW what I read...what the heck. So I went in and got on their website. Oops.

It stated that you could, for blades 3/4" and under spray Pam on the stationary blade and wipe the excess off. On bands larger than that a 50/50 mix of kerosene/chain saw bar oil could be applied sparingly while in motion.

So I got to buy a new blade and look at my chewed up brand new band saw. Fortunately it wasn't any worse.

So yeah, I was a dumba$$.

Darrin

I'd advise against lubing a blade on a running saw unless you have a mister setup. I spray Pam on a small rag, open the top of the saw and run the blade around once by hand while holding the rag on the blade with the other hand.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I was advised by an old boy years back now that if I needed to lubricate and this was more for an under powered saw just to briefly touch a candle to either side of the blade, and it works

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Formerly JJH

I learn more from my mistakes than my successes

I couldn't agree more Howard. My saw would agree too. We both learned it the hard way.

Darrin

Hey Link, you can say that again!

Darrin, holy cow! Glad I read your post before an idea like that ever popped into my head!


Mike

Makes good sense, Link. I can think of a thousand replies to the lip idea but unfortunately none of them belong here so.... I'll just say thanks!

Please could you explain why the thickness of the stock used makes a difference?

Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Dave-
It's tricky for me to explain this, but it's the same reason that it's a lot trickier to resaw a thick blank than crosscutcut a thin slat. There are more teeth/blade in the wood and more force acting to twist the blade away from the feed direction.

For testing/setting drift, I generally use scrap hardwood thicker than 1.5-2". (I keep some firewood offcuts around the shop for stuff like this.) It just seems to give a clearer 'read' on the line the blade wants to cut.

Cheers
John

Scraps of Baltic Birch plywood work great for reading drift....all those little layers in there just begging to tell on one another.

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There is no difference between the man that thinks he can....and the man that thinks he cannot.