Drunken Blade

[Ynot]

I fired up my new Jet bandsaw with riser block today with a brand new 3/4", 3 TPI blade in.

I was trying to take some 10mm thick strips of a 6" high piece of red cedar. The first one came of a but wobbly but I put that down to inexperience. The next one the blade started tracking of a about an angle of 30deg.
I checked the blade tension etc.
I tried adjusting the angle of feed to the point where I thought I was going to damage something.

ANy ideas ??

cheers
Tony

[ubeaut]

Personally I would use a smaller blade 3/8" turn the tension up to high C and feed at a very slow rate. In my experience it is almost impossible to over tension a blade, this also is something that is mentioned in videos and books on bandsaws. Probably 75% of problems come from under tensioned blades and incorrect feed rate.

If you are using a fence (which I presume you are) make sure the blade is tracking correctly by drawing a straight line on a piece of scrap timber then cutting along it without the fence.

This will show you the angle to set the fence for a parallel cut. Often the cut can be out by anything up to 3 degrees and if you try to force the timber long the fence you will end up with the blade wavering. Most saws will cut parallel to the fence first cut but often this is more a case of good luck and brut fource more than anything else.

The final possibility is that the blade is not sharpened correctly but with a new blade this is highly unlikely.

Hope this is of some help.

Cheers - Neil http://ubb.ubeaut.com.au/ubb/smile.gif

PS I find the 3/8" blade will always track better than a wider one. I have often used a 1/4" blades with great success for cutting thin veneers of timber up to 6" deep. Oh yeah, the thin blades are for the smaller saws 14" - 18", don't think I'd be using them on a 3 footer.

[DarrylF]

It's also important to get the right blade for the job. Find a good supplier who specialises in blades, tell them what you want to do and take their advice. You can get a bunch of different types of blades in the same size designed for very different types of cuts in different materials.

I know you're North of the border, but Henry Bros Saws in Windsor really know their stuff, and they do mail/phone order.

[DPB]

A few weeks back I think it was Neil that made reference to standard bandsaw fences being fairly useless. He then described what he uses. (Hope I've got this right, Neil.)

I came across this fantastic jig that is very similar to the one Neil described.
http://www.woodmagazine.com/woodmall/projects/resaw_guide.html



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Woodchuck Canuck
Good luck is the residue of good planning!

[RETIRED]

Wrong!! Twas I http://ubb.ubeaut.com.au/ubb/biggrin.gif

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Ian () Robertson
"We do good turns every day"

[DPB]

Sorry, !

Should have known - you are so often the source of all knowledge on this forum http://ubb.ubeaut.com.au/ubb/wink.gif.

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Woodchuck Canuck
Good luck is the residue of good planning!

[RETIRED]

Flattery will suffice. Crawling gets you anything http://ubb.ubeaut.com.au/ubb/biggrin.gif

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Ian () Robertson
"We do good turns every day"

[Ynot]

Thanks for the replies

I got the blade from Henry Brothers it is actually a 3/4" x 1.25 pitch blade which is what they recommended.

In hindsight I probably could have had it tensioned a bit more.
I think the resaw guide is a priority too. I had bits of wood and sash clamps and all sorts stuck on the table trying to make it work :-)

[JackoH]

Apropos the above discussion. A woody whose views I respect told me that all new bandsaw blades should be sharpened prior to use! In other words the manufacturing process tends to blunt them and much more accurate cutting will be achieved, and their life extended if this is done. Is this correct? How the heck do you sharpen a 1/2 or3/4 inch blade?
Regards John H. http://ubb.ubeaut.com.au/ubb/confused.gif

[JackoH]

The above is a serious question. Do I assume that it is a silly one, or does'nt anyone know the answer?
John H. http://ubb.ubeaut.com.au/ubb/confused.gif

[Zsteve]

john,

Haven't heard anything about sharpening new blades, thought they came pre-sharpened in the roll. Have heard of re sharpening blades with a hand held dremel or something like that, but as i have done some tool and cutter grinding before - this could easily result in uneven (if only slightly) teeth unless done on a proper setup.

Regards
Stephen

[AlexS]

I've posted elsewher about sharpening with a dremel. The way I was taught was to hold the dremel horizontal, and with the small cylindrical grinder, touch up between the tip of the tooth and the gullet. It only needs to be a touch, and yes, when you first do it they will be a bit uneven (although that doesn't seem to make any difference). After a bit of practice, you get into a rhythm and they're pretty even. You shouldn't need to reset the teeth.