Final Cut- saw blade/sanding- any others?

[rlah]

I was wondering if anyone else here has tried the Final Cut system of sanding disks on a saw blade.
I’ve used this system off-and-on for maybe 6 months... saw their demo at the Indy woodworking show. I bought their blade with the sanding disk already applied. Two things stand out:
1) I *really* like the smooth edge that comes off this system *when* it works right. Rip cuts or cross cuts both come off incredibly smooth... miter cuts are a cinch to fine tune.
2) I have had many problems fiddling with it:
a) adhesive doesn’t seem strong enough to hold anywhere near the claimed 2000 cuts
b) the blade they provided is *not* a high quality blade. They may change that in the future.

Because I like the “Final Cut” so well, I’m willing to fiddle with it. They say to use 3M 77 spray adhesive on the disk to supplement the existing adhesive. I have started to use 3M’s suggestion of spraying *both* the disk *and* the blade and then apply the disk after about 30 seconds of drying time. I think that will provide a better adhesion.
Also, when the outer diameter of the disk starts to burn, I am trimming it off with an old knife so there is a fresh edge to sand (instead of burn) the wood.
I’ve stopped using their saw blade and started using an Hitachi blade which cuts much better. I have also used it on a Freud blade with good results.

Any other experiences would be welcome to hear. (see www.finalcutblade.com)

rlah

[Knottscott]

I had one for a while last summer, and had similar experiences....worked well for a while until the sandpaper glazed over, and started to shed. Spinning at the speed of a TS blade means this happens too rapidly IMHO, which is really the achilles heal of this system, and I know of no way around it at this time. I also felt that the supplied blade was pretty poor, but I didn't try the paper on other blades. It seemed to be a concept that started behind the 8-ball due to the RPM of the TS, and I never really warmed up to it much.

[Sid]

I found that the success achieved with the Final Cut sanding disks depends on the blade to which they are attached; specifically on the difference between the thickness of the blade plate and the width of the carbide teeth, i.e., the protected thickness available for the sandpaper.

I have the sandpaper disks on a Freud 10", full kerf, 24 tooth, rip blade for the table saw. It has a plate thickness of .090" and a tooth width of .124" for a difference of .034". That leaves a protected thickness of .017" on each side for the sandpaper. The thickness sandpaper-to-sandpaper, after a fair amount of use, is the same as the width of the teeth. I've had no problems with it, and it gives beautifully smooth cuts.

I also have them on a Dewalt 12", thin kerf, 60 tooth, crosscut blade for the SCMS. It has a plate thickness of .074" and a tooth width of .098" for a difference of .024". The protected thickness on each side is only .012". The thickness sandpaper-to-sandpaper is .105" which is greater than the tooth width. I was using it on soft woods and getting the same smooth cuts. But then I used it on some oak and got burning on about half an inch of the rim of the sandpaper.

I conclude that the sandpaper needs the extra protected space, but when it's not available, the sandpaper can open a kerf wider than the teeth in soft wood, but not in hardwood.

Sid

[rlah]

Sid:
Thx for the in-depth analysis... I'll study your numbers more... I may want to buy a full-kerf blade like yours to see how it works. It makes sense to me that if the sanding is taking off less, it will do it's job much better... especially less burning in hardwoods.

So you aren't having any problems with the adhesive not working well enough on either the 10" full kerf or the 12" thin kerf? Are you spraying the 3M 77 adhesive on the disk like the manufacturer suggests?

Are you getting long service life with the 10" full kerf blade?

rlah

[Sid]

Riah:

Yes, I suspect that full-kerf blades in general will allow more room for the sanding disk as described above, but I'd use a caliper to check any specific blade.

No, I haven't had any problem with the adhesive not holding, and the Freud blade has the red coating, which I think is teflon. I bought my sanding disks at the St. Louis show over two years ago, shortly after they were brought to market. I don't think there was any recommendation to use a spray adhesive at that time, and I didn't even realize it's recommended now.

"Long service" is pretty subjective. I've had them quite awhile, but don't get into my shop nearly as often as I'd like. I'm well satisfied with them on the full-kerf blade.

Sid

[cgallery]

I once thought about purchasing some of the sandpaper and applying it to an old blade to use as a disc sander. I have one of those 10" sanding discs from my Craftsman 10" contractor days, but I don't use it because of the RPM of the BT3K. I could either get a router speed control, or I could get some of the sandpaper for the Final Cut and try that as an option.

[rlah]

Sid:
You don't happen to have handy the model # of that 10" Freud 24T full kerf saw blade by chance? (Maybe they're all alike on thickness I suppose)

cgallery:
I would wonder that the Final Cut sanding disks may be special made for the higher TS speeds. So I would agree to get a router speed control if using some other sanding disk system. But I think this is a great idea to get a disk sander without buying a new system. I think the Final Cut sanding disks are Swiss made...

[Knottscott]

Sid:
You don't happen to have handy the model # of that 10" Freud 24T full kerf saw blade by chance? (Maybe they're all alike on thickness I suppose)

cgallery:
I would wonder that the Final Cut sanding disks may be special made for the higher TS speeds. So I would agree to get a router speed control if using some other sanding disk system. But I think this is a great idea to get a disk sander without buying a new system. I think the Final Cut sanding disks are Swiss made...

Freud's only 10" full kerf 24T ripper is the LM72R010 (Permashield coating) or LM72M010 (no coating on older models, clear ICE coating on newer ones). The Infinity 010-024, Amana RB1020, and DeWalt DW7642 (series 60) or DW7124 (series 40) would be very similar.

[Sid]

Sid:
You don't happen to have handy the model # of that 10" Freud 24T full kerf saw blade by chance? (Maybe they're all alike on thickness I suppose)

Sorry, but I'd have to pull the sandpaper off to read the model number!

Judging from Knottscott's post, it's probably the LM72R010. I think the "R" stands for the red coating that mine has.

Sid

[rlah]

Sid:
Thx for the reply.
I was able to get to our Rockler store over the weekend and got the Freud LM72R010 with the 20% off coupon. I got the measurements off the blade in the store... it's the right one with the dimensions you described above. I took my precision dial indicator in the store and the clerk opened the package to let me do this. Wow, what a nice blade... super sharp, massive carbide tips, full kerf with flat top grind. I was going to buy the Freud 8" Dado set at the same time, but this blade will be quite sufficient for my limited dado/tenon cutting needs.

I have not even put the sandpaper on -- it leaves such a nice smooth cut edge. It is whisper quiet... stiff with no deflection, a strong blade... I see Freud advertises it as a "glue-line" blade. I suppose I'll get around to putting the Final-Cut sandpaper disks on sometime but I am having so much fun with this blade, it might be awhile... ... did you see an improvement when you put the Final-Cut sandpaper disks on?

Anyway, I'm glad you mentioned this blade. I feel like I got 2 blades with it's versatility. (I'll report later about the Final-Cut disks on this.)