Bandsaw problems

[JustBen]

I bought a cheap draper second hand bandsaw a while back and it wouldn't cut straight or properly.

I tried everything to get it working right. I made all new top and bottom guides replacing the graphite? guides with bearings. I balanced the wheels. I re-aligned everything but still it wouldn't work. I was told that it was a new blade when I got it.

I had almost given up on it when I decide to try a new 1/2 blade instead of the 1/4 blade that was on it when I got it.

Now it cuts well and straight.

So my questions are....

Is it cutting straight now because I have a 1/2 blade on it?
Are 1/4 blades normally problematic?
Is it likely that the 1/4 blade was blunt in the first place.

The old blade seemed to be sharp enough. It chomped through the first 1" or so fine but struggled as it started to veer off course. The new one flew through a 4" block of wood no problems.

I know there may not be a definitive answer.

I don't want to waste money on another 1/4 blade if I'm going to have the same problem.

I am in the process of building the 'Mathias Wandel bandsaw' so won't be using this one for a great deal longer.

Thoughts?...

 

[powertools]

First point if you are building the 'Mathias Wandel bandsaw' you may well be using this one for a long time to come.
Only you know if the 1/4 blade was blunt but a 1/2 blade will always be better for straight cuts.

 

[disco_monkey79]

Mine (hobby-sized jet) cuts straight, irregardless of blade width. Will be intetested to read other replies. Before the jet, I tried a 2nd-hand bbs20 that simply refused to cut straight. Even my dad, an experienced machinist, got fed up with it.

Glad you got your draper sorted.

 

[Phil Pascoe]

It's usual to use a wider blade for straight cuts and narrower ones for curves, but your narrow one might have had a slight hit on one side, which would make it wander. Get your blades (and advice, if needed) from Tuffsaws.

 

[marcros]

what tpi was on each blade? my bandsaw seems pretty well set up, but when i tried to cut something a bit thick with a 6/10 tpi blade, it was hopeless.

 

[JustBen]

First point if you are building the 'Mathias Wandel bandsaw' you may well be using this one for a long time to come.

Why is that?

The 1/2 is a 6tpi but sure not about the 1/4. It's a finer toothed one. Maybe a 14tpi?

To be honest, the 1/4 wouldn't even cut curves very well. I can cut a tighter curve with the 1/2 than a can with the 1/4.

The more I think about it, the more I think it was a duff blade.

 

[marcros]

the 1/4" blade couldn't clear the dust- too many teeth by far. It was probably also blunt and poor quality if it was on the machine when you got it.

 

[wizard]

Cheap blades never cut straight, use starrett blade and you will get a perfect cut. If you have to push the wood the blade will wander .

 

[Jelly]

First point if you are building the 'Mathias Wandel bandsaw' you may well be using this one for a long time to come.

Why is that?

I suspect the poster feels that a self-built bandsaw is unlikely to actually work... which actually depends on the quality of execution really, rather than the bandsaw design itself.

 

[Phil Pascoe]

1/4" x 14tpi? sounds like it might be a metal cutting blade? That would explain a lot.

 

[powertools]

Sorry if you got me wrong. There is nothing wrong with the design if you want a project. There is nothing wrong with the Draper saw if you want a bandsaw.

 

[custard]

The single most important component on a bandsaw, by a country mile, is the blade. It needs to be sharp, as wide as practical (but not too wide or else you won't be able to tension it adequately), and it should have as few teeth as possible (so that it can clear the sawdust effectively).

If you get a good quality blade with those characteristics it's amazing how good the cuts can be from even modest bandsaws.

But with the wrong blade you'll tinker and fuss for hours and the results will always disappoint.

 

[JustBen]

Sorry I got my numbers wrong. The 1/4 is a 6tpi. I thought it was finer than that. Duff blade I think... and a mile wide guess by me.

I still don't see the issue with the homemade bandsaw. I've built other machines by him and they have worked perfectly.

I don't have the £100s needed for a bandsaw that size but I do have lots of timber, motor and other bits that will enable me to build it for next to nothing.

 

[MARK.B.]

You can have the most expensive bandsaw in the world with all the bells and whistles attatched but if you have a crap blade you will get crap results,contact Tuffsaws and they will reccomend a quality blade for your saw.

 

[Steve Maskery]

Sorry, I missed this.
Your bandsaw should take 1/4 and 1/2" blades equally successfully. You've already been pointed in the direction of Tuffsaws and I endorse that advice.
The TPI count is determined by the thickness of your wood. As Marcross, using a fine-toothed blade on thick timber doesn't work, because the small gullets get clogged up. Big wood needs big gullets.
Once you have selected the right blade for the job you need to ensure that your wheels lie in the same plane, the blade is tensioned properly and you have eliminated tracking problems. The guides are the least important aspect, really.
Your machine will then cut beautifully.
S