Which Blade for a band saw

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dgoddard

Which Blade for a band saw

Post by dgoddard »

For those who saw my previous post on "Which Band Saw", this is a natural follow-on. An Enco 5x6 saw with a 1/2 hp motor should be arriving in a few days. In additon to the usual amount of assembly, the motor comes separately when the 1/2 horse motor is purchased, (unless of course you want to wait a week while they put it together).

I already have one recommendation that the blades for the portable saws made of .020 instead of .025 inch thick material will stand up better. But what tooth pitch should I be looking for? [img]/ubb/images/graemlins/confused.gif"%20alt="[/img]

I will be cutting steel mostly and a bit of aluminum and brass. I will want to use it as a vertical saw occasionly as I do not have a vertical saw or the space for one (Actually it will take some rearrangeing to get this one in place).

Is it even practical to try to get by with only a single sort of blade or is it necessary to plan on changing blades for various cuts? [img]/ubb/images/graemlins/confused.gif"%20alt="[/img]

come to think of it, the saw has speeds of 80, 120, and 200 surface feet per minute. Which speed does one use for what purpose? [img]/ubb/images/graemlins/confused.gif"%20alt="[/img]
jpfalt
Posts: 982
Joined: Sun Jan 05, 2003 12:55 pm

Re: Which Blade for a band saw

Post by jpfalt »

The tooth pitch depends on the thickness of the material you are cutting. Ideally you have a minimum of 2 teeth in any single wall of cut. so for 1/8 material, 24 teeth per inch. It's actually 1/8 divided by three as one tooth comes onto the work as one leaves. For 1 inch material, you could go up to a 3 tooth per inch skip tooth, but that gets a bit nutty unless everything you cut is 1 inch length of cut.

Personally, I keep some 32 tpi blades for thin stuff and some 18tpi for thicker material.

For SFM, use the slow speed unless you want to change speeds regularly. For steel, if you are running a bimetal blade it should run at about 90 SFM. For aluminum and brass, run wide open. Running aluminum or brass slower than wide open won't hurt the blade and will most likely extend it's life. Running a bimetal blade faster than 90 sfm will cut somewhat faster, but will shorten the life of the cutting points.
Doug_C
Posts: 1254
Joined: Sat Jan 04, 2003 6:48 pm

Re: Which Blade for a band saw

Post by Doug_C »

Much of your blade choices can be limited to the strength of the machine and keeping the blade on the wheels. This can be controlled to some extent by the feed. As if that feature is available on these cheaper saws. I thought some were hand control only or some counterbalance spring. Simple to add an air cylinder with a couple flow control valves to solve inconsistant feeds. Mine has a self contained hydraulic cylinder that transfers the oil from the bottom to the top. Only a small bleeder valve is in the top. Very nice for such a small saw.

Primarily I use 14 and 18 TPI for my Craftsman of the same size. I use a oiler can to lube the cut and catch the drippings on a cookie sheet. Collect the oil again and re-use it. AM I cheap or what? [img]/ubb/images/graemlins/blush.gif"%20alt="[/img]

You can have a couple of 4, 6 and 8 tooth blades on hand for soft materials. Keeping the forces under control to keep the blade from slipping on the wheels is the best answer. Course teeth like to take a bigger bite. Finer blades really slow down the cutting progress. As has been stated, when cutting thinner materials like pipe and sheet metal. These can and will strip teeth off the blade if allowed to be force fed to fast.

Standard carbon blades normally work fine if you keep the SFM within the materials cutting range. Bimetal blades will run 2-4 times the cost of regular carbon blades. As long as you test every steel piece of material you plan on cutting with a file to determine if it will cut. Then take into consideration how big the file chips were to assess its hardness in relation to blade speed required. Carbon will work fine and Bimetal will pay off in greater life expectancy. One contact with something too hard or cut at too high of a blade speed will kill either blade. You must decide whether $4-6 bucks or $10-$20 is worth the investment.

DC
d_goddard

Re: Which Blade for a band saw, Best Prices

Post by d_goddard »

$4 to $6 per blade?

Where do I find those prices?
Doug_C
Posts: 1254
Joined: Sat Jan 04, 2003 6:48 pm

Re: Which Blade for a band saw, Best Prices

Post by Doug_C »

Here you go Don,

The latest free shipping promo-code was listed somewhere here a couple weeks ago.

Enco sale

I like their misprint of "CARBIDE STEEL BANDSAW BLADE ". I am fairly certain that should be Carbon Steel!

There used to be a lot more on eBay a couple years ago when I was looking.

I ended up running across a blade welder(Free) and collected some various 1/2" blade stock. Now I can weld up most any blade I might need for dirt cheap. I have even cut and drilled some for hack saw blades. How is that for being cheap! [img]/ubb/images/graemlins/grin.gif"%20alt="[/img]

DC
Tusculum

Re: Which Blade for a band saw

Post by Tusculum »

Ive been knee deep in this for the last week! Been trying to cut 3/4"Class3 Copper with a 18TPI blade. It wont work. Done a little research and found out the softer the material the coarser the blade teeth. Travers Website had Starrett blades for 12.00 that went to a 6TPI and I ordered one for the copper. It didnt like it but it cut it! Finally finished the copper and had a run of 3/8 thick D2 tool steel. I didnt fool with changing the 6TPI just to see if it would cut it and it ate through it like butter"With a lil Kroil" to help keep the blade cool. When cutting soft metal Id use coarse blades and Kroil and the slowest setting on the band saw. The kroil keeps the material and blade seperated so it wont gum up, but after using the 6TPI on the D2 I think it will work for most anything. My lil saw is a 20 year old Jap job that takes 5'4" X1/2 blades. HTH.....Jack
JimGlass
Posts: 2281
Joined: Sat Jan 04, 2003 8:33 pm
Location: 40 Miles West of Chicago/near DeKalb
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Re: Which Blade for a band saw

Post by JimGlass »

There are 2 kinds of saw blades, bi-metal and flex back (carbon) blades. Not untill I started my own shop did I learn about saw blades. The flex back (carbon) blades usually sell for $6 ot $10. They are used for sawing aluminum, wood, plastic etc. The Bi-Metal blades are for sawing steel, iron and tool steels. Bi-metal blades cost 3 to 5 times more than carbon blades but last 20 times longer when sawing steel.
You do the math??
It took me 35 years to figure that out.
Jim
Tool & Die Maker/Electrician, Retired 2007

So much to learn and so little time.

www.outbackmachineshop.com
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