Baffled by bandsaw

[Gerard Scanlan]

I forgot to mention that if the blade is blunt it will misbehave terribly as will a badly welded blade and you need a 3 or 4 teeth per inch blade for resawing anything over 3 cm thick so definitely for a piece 15cm thick. More teeth per inch will not clear out enoug of the sawdust and will cause the blade to wander.

 

[Just4Fun]

Thanks to all for the continued suggestions. I have been thinking a lot about this and I am reaching some conclusions I don't really like.

First, I don't think I am going to bother trying to use this machine again. I have tried it several times now and all I do is waste wood. I don't know enough about it, I am not really free to keep playing with and adjusting the machine, and even if I got it working well it is likely to be as bad as ever next time I want to use it.

The knock-on effect of this is more of an issue. This machine is at my weekly woodwork evening class and I have to question why I go there at all. There is no tuition to speak of. None of the machinery there is particularly useful to me so I don't do anything there that I cannot do as well or better at home. The only benefit is the social side of things and I wonder if that is worth the effort of packing up my tools and carting them to the class each week. For the last 2 weeks I have thought "sod it" and stayed home.

 

[Sideways]

Don't knock the social element. If there are folk there whose company you enjoy, that's valuable in itself.
Maybe just readjust what you use the place for. Small, handwork intensive projects like jewellery boxes and carving maybe where you can take your own trustworthy tools without too much trouble.

 

[TheTiddles]

Old thread I know, but it seems like your teacher could do with a few lessons themselves. Glad to see you had the sense not to do something dicey.

I was going to suggest maybe a local member would help you out with one of their machines... then I saw your location

Aidan

 

[Steve Maskery]

My, admittedly very limited, experience of shared community workshops is that there are people who know what they are doing and there are people who do not. It's not always the "knowers" who get to be in charge of the machinery. Seniority of tenure is not a proxy for competence...

 

[Just4Fun]

Don't knock the social element. If there are folk there whose company you enjoy, that's valuable in itself.
Maybe just readjust what you use the place for. Small, handwork intensive projects like jewellery boxes and carving maybe where you can take your own trustworthy tools without too much trouble.

Good advice there and I decided to take it ... but things change so just to round off the story here is the outcome.

I went to my class and the instructor suggested another attempt with the bandsaw; he had obviously been playing with it to get it working better. The changes he had made were:

He had fitted another new blade. This looked to be a significantly wider blade than those we used earlier. I measured it at .75 inch. I don't know what size the earlier blades were.

Also this blade was 4 TPI which I think is less than the earlier blades but again I don't know what they were.

We clamped a piece of timber in place to use as a fence and this was also different to before. It was clamped at an angle. From what I understand (there is a language barrier) the table of the bandsaw is not aligned with the blade, so now the fence was clamped at an angle rather than parallel to the edge of the table, in order to be parallel to the blade.

I tried to resaw a piece 165mm wide, without first creating guiding kerfs using the table saw. It worked fine! The surface was quite good and fairly flat so easy enough to smooth using hand planes.

So the end result is that the saw now works as I expected it to do when I first tried it weeks ago. That makes a big difference to me, especially if I am able to do that consistently.

 

[Peri]

............so now the fence was clamped at an angle rather than parallel to the edge of the table, in order to be parallel to the blade.

I think thats the biggest problem there - if the fence isn't parallel to the blade I don't see how you could ever hope the resaw anything

 

[Steve Maskery]

LOL! Yes, a coarser blade will make ripping easier as will a wider blade, assuming that the saw is big enough and strong enough to tension it.
Skewing the fence, as he has done, will, as you can see, "solve" the problem - for ripping. But you try crosscutting with the mitre fence or using any kind of kig that is mounted in the mitre slot and the cut will not be true, because the workpiece is no longer travelling parallel to the skewed fence.
The correct approach is to set the fence parallel to the mitre slot and then adjust the tracking knob of the top wheel to ELIMINATE drift, rather than just compensate for it. That way, rip cuts are trues AND SO ARE CROSSCUTS.
TBH, it sounds like the blind leading the blind; not an uncommon scenario I fear, in such establishments.

 

[Just4Fun]

TBH, it sounds like the blind leading the blind; not an uncommon scenario I fear, in such establishments.

Yes, I think that is accurate.

BTW Your comments about crosscuts and the mitre slot may well be correct in most cases but are not applicable in this case. There is no mitre slot! Not that I am bothered by that. I don't think I have ever wanted to do crosscuts on a band saw. Usually crosscuts are quick & easy to do with a hand saw. A couple of times I have used the table saw but only when I have had a lot to do.