How to straighten bandsaw blade

[Al Launier]

David,

I braze my own blades from a bulk roll that I bought on eBay so my cost is around $6 to $7 each for 133" blades that fit my 18" bandsaw. I no longer worry about saving a bent or twisted blade at this price. S

earch youtube for videos on brazing bandsaw blades using silver solder with a propane or Mapp gas torch.

Karl I tried to PM you, but you have it turned off. I totally agree with you in making up your own BS blades. I do it not only for the savings, but more so just to learn how to do it and to get the satisfaction of being able to do it. I made my own brazing fixture to hold the blade while brazing, nothing fancy but it works, and use a Mapps torch. I wonder what your fixture looks like, if you also use a Mapps torch, and what you use for flux. Admittedly, the blade does thump a bit after grinding, but unless I need a cleaner cut it'll do.

[John K Jordan]

John

In that last picture are you cutting a round blank just by hand? I made a simple jig that uses a 1/4" dowel that's adjustable. I put a shallow 1/4" hole in the blank so it can pivot on the dowel. The hole is in the center of the bowl so it gets removed.

Yes, a jig is simple to make. I always cut by hand, even simpler.

I also cut blanks that would need a complicated jig.

IMG_7484.jpg

JKJ

[Alex Zeller]

I can cut off corners but trying to follow a line to make a round circle, I haven't had much luck. But the only band saw I have at the house is a cheap Delta clone. It's set up correctly but it wasn't built with quality in mind. I do have a nicer Laguna but use it where it's located so I might just buy something for my home shop. I asked because I'm wondering how much is me and how much is the equipment.

[John K Jordan]

I can cut off corners but trying to follow a line to make a round circle, I haven't had much luck. But the only band saw I have at the house is a cheap Delta clone. It's set up correctly but it wasn't built with quality in mind. I do have a nicer Laguna but use it where it's located so I might just buy something for my home shop. I asked because I'm wondering how much is me and how much is the equipment.

It's probably all you. (just kidding!) A reasonable saw is a help but you can cut good circles with nearly any saw if the blade is not too wide. I use 1/2" wide blades. One common rule-of-thumb is limit the curvature to a 3" radius, or a 6" circle, for a 1/2" blade. There is a tiny bit more going on there, such as the amount of set in the blade, the thickness of the blade, and if the back of the blade is "stoned" (radiused and smoothed with a sharpening stone or diamond hone while the machine is running.) I have no trouble cutting a 4" circle with the 1/2" blades I use but larger circles are easier.

I draw the circle with a big compass or easier, with this: https://www.amazon.com/The-Bullzeye-.../dp/B004TK0JOO A clear template is wonderful for sliding around on a slab to find the best figure while avoiding any defects.

If the line is not easy to see I make it darker with an extra fine sharpie. On dark walnut I use a special fine-line white pencil. Cut in from the side and start rotating the blank, cutting just outside the line. I find the trick is to imagine rotating around the center, just as if using the jig. If I get a little too far outside the line I back up and clean up that part. If needed I make a cut to the outside so I can discard the waste then pick up the cut again. I've cut blanks up to maybe 8" deep this way. It's really not necessary to cut a perfect circle since small corners can easily be removed while turning, but I like to be able to see the wood and it sure makes the blank more attractive to a prospective buyer so I do this for bowl blanks I take to our annual club wood auction.

JKJ