Report on a successful short term fix.

[CameronPotter]

Hi guys,

On the weekend I was finally getting my bandsaw running (after needing to replace lots of parts), started the thing up and the bottom tyre flew to bits! :mad:

However, I went down to the local servo and though I would ask for an old car inner tube as I have heard that is an OK part time fix - but they also sold bike inner tubes. I bought a kid's inner tube cut it into three widths (maintaining the continous loop of the tyre) and used these. It worked very well. I am not suggesting that this is a permanent fix, but it is a good stop gap method.

Now the question part:

Also, I was wondering how fast do blades usually blunt? I was running a 25mm blade it through some black wattle logs (pretty big actually - only just small enough to fit through my 17" saw). The first log was a dream, but then it got worse - I am assuming that meant the blade was getting blunt. This means that it got blunt pretty quickly; it still cut, but a lot more slowly and it binded a lot. By the end, it basically wasn't wanting to go through the wood. It was still fine for thinner stuff though. I am thinking that log resawing should maybe only be attempted with brand new blades?

[AlexS]

I've never cut black wattle, but blackwood does seem to blunt the bandsaw fairly quickly. However, in this case, it's probably a build up of resin on the blade, particularly if the wood was green. Oven cleaner is good for removing the resin.

[DarrylF]

As AlexS says, clean off the gunk first.

Any blade larger than say 12mm can be sharpened pretty easily using a Dremel or similar. Doesn't really take all that long and you'll be surprised how good the results can be.

Best do a search on the 'net for the best technique though - not sure I'd rate as an expert :)

[Greg Q]

How many teeth/inch on that blade? I have a 1 1/2 teeth/inch 25mm bi-metal
blade that works very well, got it from Henry Bros in NSW. (My current favourite supplier of anything woodworking).

Anyway, if you do have a pitch problem, mag wheel cleaner also works well
(just spray and wipe)

Hope this helps...

Greg

[echnidna]

some timbers (eg blackwood) have a lot of silica which blunts the blades fast.
Dunno bout black wattyl - it might be the same.

[KevM]

Also, I was wondering how fast do blades usually blunt? I was running a 25mm blade it through some black wattle logs (pretty big actually - only just small enough to fit through my 17" saw). The first log was a dream, but then it got worse - I am assuming that meant the blade was getting blunt. This means that it got blunt pretty quickly; it still cut, but a lot more slowly and it binded a lot. By the end, it basically wasn't wanting to go through the wood. It was still fine for thinner stuff though. I am thinking that log resawing should maybe only be attempted with brand new blades?

Cameron,
A couple of questions for you.


Were the logs still green? Cutting a dry log will take the edge off your teeth a lot quicker.
Were the logs debarked? Bark can harbour a myriad of items. ie small rocks & dirt which will remove that edge quickly.
Were the logs clean? Dirt will also take the edge off your teeth, we always hit our logs with a high pressure water cleaner before using the bandsaw shown in my avatar.



Kev M

[Don Nethercott]

At Grafton Artsfest I did Alan Williams Bandsaw Boxes course. We we going through a blade a day, and there were no hard woods being cut, mainly cedar, camphol laurel and mango.

Blades do have a limited life - depending on how often and how hard the wood. As said above, green wood etc can gum up blades.

Make sure you use the right blade for the right job. Mark Duginske's book Band Saw Handbook is a good guide.

Don

[zenwood]

Sounds like par for the course:

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=22046

I think new bandsaw blades quickly lose their as-new aggressive sharpness, and settle into just ordinary sharpness. Slow speed feeding might help, but half a day's resawing hardwood for a home-handyman type bandsaw is probably going to challenge most bandsaws.

[CameronPotter]

Thanks for the replies.

I think that Zenwood might have it right - the saw was still cutting away, but I just needed to be a LOT slower on the feed and it did bind more. Maybe the over cleaner is worth a look too.

The logs were relatively green, the first one wasn't (and it cut beautifully) the next ones were and were worse - maybe that underlines the oven cleaner thing...

The bark was stripped and the logs were clean - but not high pressure hose clean.

Greg, my saw blade is the same as yours - maybe the cleaner really is the go!

Finally, Darryl, I might give sharpening it a go - I would have thought that would have taken a LONG time though...

Thanks again

Cam

[DarrylF]

Finally, Darryl, I might give sharpening it a go - I would have thought that would have taken a LONG time though...


All you need to do is one stroke on each tooth if you have a decent stone in a Dremel. A chainsaw sharpening bit would work well - pretty sure Bunnies sell a diamond bit for the purpose. You won't get done in 30 seconds, but I reckon it's worthwhile for larger blades. Once you get into the swing of it it's really not too big a job.

[Auld Bassoon]

All you need to do is one stroke on each tooth if you have a decent stone in a Dremel. A chainsaw sharpening bit would work well - pretty sure Bunnies sell a diamond bit for the purpose. You won't get done in 30 seconds, but I reckon it's worthwhile for larger blades. Once you get into the swing of it it's really not too big a job.

I guess that's true DarrylF, but for my Electra Beckum 14" B/S, a new 12.7mm blade, 6tpi, from C&S is around $13. I don't know what you spend on your hobbey, but for me $13 every couple of months is a pretty good deal compared with a couple of (precious!) hours faffing around with an old blade...

Cheers!

PS that remnds me - call C&S tomorrowhttp://www.woodworkforums.ubeaut.com.au/images/icons/icon7.gif

[DarrylF]

Last time I did one it probably took me 20 minutes, and the blade cut better than new when I was finished.

Not something I'd love to be doing every weekend, but it's definitely a worthwhile option with a big blade, no spares and a bunch of timber waiting to be cut.

[Termite]

I have to agree with DarrylF, I've found my blades, particularly 1" resaw blades, cut better than new after a sharpen.

[CameronPotter]

Once every few months!?! I guess that means that either you don't use it much or you don't feel the need for that "as new" sharpness...

[scooter]

Cleaning - can use Simple Green from bunnings or reject shop. Alternative to dedicated blade cleaner or oven cleaner, cheap and reasonably benign. Has been discussed before, do a search if interested.

Sharpening - Diamond chainsaw hone in Dremel or el cheapo rotary tool should work well, if you have the time. Seem to recall someone bought a cheap wheel-type chainsaw sharpener for this purpose, once again, search might be in order.

Ahyup, here 'tis, 'twas DavidG
http://www.woodworkforums.ubeaut.com.au/showthread.php?t=22550&highlight=chainsaw

Good luck...........cheers.............Sean