Thread: Which CMT table saw blade for professional frames ?

I was going to suggest a negative rake blade, Jake.

The 10 degree positive hook is better than the more aggressive ones if you've got to use CMT. I'd look to a steel blade or an aluminium blade at about 80 tooth - Irwin??

Cheers,

eddie

thanks, I'll check irwin as well ,,well there are negitive rake ones with CMT too....3 types. all got minus 5 degree rake....24, 48, and 64 teeth.....all 81/2" blades though. Not the 10 or 12" ones I'm used to.

I'm finding it all a bit confusing.

Hang on.....there's blades for melamine and chipwood as well......they'd cut laminates well...... the painted coating of moulding is similar stuff isn't it......maybe one of those is the go.

Jake
in general, when cross cutting the more teeth the better.

to help with the chipping, try packaging tape, or low stick (I think it's Blue) masking tape around where you need to make the cut. This should hold the fibers together where the blade exists the piece.

ian

Ta Ian. I know what your saying. Do you think it'll stop that paint clicking off though......I can see where a gulitine type tool would avoid this paint problem.

I agree on the number of teeth. But there seems to be many types with lots of teeth.

Jake
the guilitine basicly works the same as a low angle plane
as I understand it you cut the material a few mm too long and then guilitine (plane) it to length
so if the using a low angle plane and shooting board caused chip out, I'd expect a similar result with the guilitine

hopefully one of the others will say different

ian

Those hand operated guillotines aren't as good as these foot operated units. They are perfect for fine finicky work, but are pricey.

Before buying anything, try putting some masking tape on the mitre, rub over it with something hard to make sure it has a good bond over the entire surface and then try taking fine cuts on the saw.

I can get chip free clean cuts with small mitres on my wobbly cr@p GMC SCMS.

EDIT: oops, just read Ian has already mentioned about the tape.

Originally Posted by ian

Jake
the guilitine basicly works the same as a low angle plane
as I understand it you cut the material a few mm too long and then guilitine (plane) it to length
so if the using a low angle plane and shooting board caused chip out, I'd expect a similar result with the guilitine

hopefully one of the others will say different

ian

I'm pretty sure, at least from other conversations I've had, that the guilitine works better than a shooting plane in that it can slice even lower..., cause there's no bed. ie. you gota have some meat under the blade of a plane.....not an issue with the guilitine.

My shooting planes handle any mitre fine.....its just that fine paint layer on top thats causing the problem( I don't normally shoot this pretty shiiiiite).......it seems ok as the plane blade strikes parts of the profile that are curving up(where the mouldings backing up the paint)....but not down.....when the profiles going down it can clip this paint layer from behind, and flick off a little bit of paint,,,,and it looks ugly.

I don't think the problem exists as much if the saw cut drops straight down on the moulding because the paints being backed up by the moulding under it.......thats I why I think the local framer I know is quite fond of his makita sliding compound mitre saw....he says he uses it when his quiltine blades are bluntening. Says it works fine.

But your coming moreso into the side of the moulding with a table saw. Which I think is the problem in general with it......but I haven't got a compound mitre saw or a guilitine, and I can't afford either right now. But I can buy a blade. So, fingerscrossed I was hoping I could buy a blade that may have enough teeth or ground a special way to still work on the table saw. Just haven't had enough experience on tablesaws with man-made crap to know.......

All I know is that my current blade, even when moving the moulding very slowly through, still flicks off a bit of this paint here and there.

I'll give the tape a go tomorrow morning. Thanks fellas.

Originally Posted by apricotripper

I'll give the tape a go tomorrow morning. Thanks fellas.

Why don't you scribe the line with a marking knife where you are going to cut first.It will take longer of course but it should stop the paint from chipping.

Originally Posted by Woodlee

Why don't you scribe the line with a marking knife where you are going to cut first.It will take longer of course but it should stop the paint from chipping.

see what you mean.....but it would be a tricky scribe wouldn't it ? .....mouldings curves about uno.....the ruler that the knife runs on is flat,,,,, I'd find a flat straight edge on a curved moulding be hard to scribe off.

Fiddly.

Originally Posted by apricotripper

I don't think the problem exists as much if the saw cut drops straight down on the moulding because the paints being backed up by the moulding under it.......thats I why I think the local framer I know is quite fond of his makita sliding compound mitre saw....he says he uses it when his quiltine blades are bluntening. Says it works fine.

But your coming moreso into the side of the moulding with a table saw. Which I think is the problem in general with it......but I haven't got a compound mitre saw or a guilitine, and I can't afford either right now. But I can buy a blade. So, fingerscrossed I was hoping I could buy a blade that may have enough teeth or ground a special way to still work on the table saw. Just haven't had enough experience on tablesaws with man-made crap to know.......

All I know is that my current blade, even when moving the moulding very slowly through, still flicks off a bit of this paint here and there.

Jake

Before investing (or outlaying) your scarce $ for a new blade, it would be worth experimenting with a mitre cross-cut sled on the saw and the orientation of the moulding.
the sled is to back up the moulding as you cut and the orientation is so that as the moulding passes through the saw the cutting action is similar to that achieved with a drop saw.

for what it's worth, my 10" Makita SCMS has an 80 tooth (Makita) blade and cuts really smoothly. Dad's Timbercon (sherwin) clone has a 60 tooth blade and doesn't cut near as well


ian

Originally Posted by ian

Jake

Before investing (or outlaying) your scarce $ for a new blade, it would be worth experimenting with a mitre cross-cut sled on the saw and the orientation of the moulding.

I agree. Did that this afternoon. I'll go get some pictures.

Originally Posted by ian

the sled is to back up the moulding as you cut and the orientation is so that as the moulding passes through the saw the cutting action is similar to that achieved with a drop saw.

But I disagree here. Similar, but I think the action of the blade on a table saw cutting at a moulding is more of a sideways action than that you find in that SCMS.......you can chop straight down with the SCMS can't you , in one shot mostly? (for most moulding anyway)...... I mean with the teeth hitting the paint first always (good because backed up by mdf)

and I realised something today, supported by a couple of experiments....the higher the blade is off the table, the cleaner the finish.....ie the teeth are chopping down more.

So, I gota keep the blade as high as possible. Made the finish nearly passable

I'll go get a picture to be clear. Show that mitre guage I said I'd make too(mentioned it in that mitre thread of yours)....

Jake
I'm thinking that you might hold the moulding in a possibly V-shaped fence so that the blade cuts into rather than across the section.


ian