Thread: Looking for flat tooth blade

I have an Infinity combo blade that meets those requirements - the sequence of teeth isn't all flat, but the resulting cut has a perfectly flat bottom. Obviously at least one tooth in each set is ground flat and at the full cut height; the intermediate teeth are chippers to reduce the cutting forces. These combo blades are excellent for ripping and crosscutting, so mine rarely leaves the saw. They also have 5/8' arbor pretty much as standard (fits my JET saw).

10" Combination Saw Blades

I got mine years ago from a distributor in Oz, but I suspect you'd have to order online from the US now.

You may find some other combo blades work the same way, although my Freud combo doesn't. As long as one tooth in each group is ground flat at full length you'll get a flat-botomed kerf.

saw.jpg

I'd be wary about expecting any blade with a single flat tooth amoungst triple chip and atb grind teeth to produce a flat bottomed groove. I've never seen a blade like Mr Brush's before, and if you think about it there's not much point in producing a blade with multi tooth geometery when the flat tooth is the one cutting the deepest.

I use a Dimar FTG for ripping, a Flai ATB for crosscutting and I have a CMT triple chip for panel materials.

My recommendation would be to buy a Flat Top Grind (FTG) that meets your specifications.

You could buy a common Alternating Top Bevel (ATB) and have it reground, but that would involve taking enough off the tops of the teeth to get them flat that you've significantly shortened the blades lifespan.

Originally Posted by aldav

I'd be wary about expecting any blade with a single flat tooth amoungst triple chip and atb grind teeth to produce a flat bottomed groove. I've never seen a blade like Mr Brush's before, and if you think about it there's not much point in producing a blade with multi tooth geometery when the flat tooth is the one cutting the deepest.

I thought Triple Chip Grind (TCG) alternated trapezoidal teeth (ie. the 1st tooth in the set) with flat teeth and the flat teeth were set slightly lower than the centre of the trapezoidal? Really for other materials like chipboard, plastic or really hard woods.

I've never seen one like that pictured either and it doesn't look to be ATB either. (Alternating Top Bevel) Both bevels (3rd & 5th teeth) seem to be the same direction... not ATB in my books.

The 4th tooth in each set looks to be FTB, but if the 2nd is properly TCG and is set for a lower height, then perhaps the 4th tooth is full depth? Or is camera perspective skewing things so that tooth is actually bevelled t'other way?

Dunno... and I'll take Mr Brush's word that it works well for his usage. Personally I don't think I'd commit any pennies unless and until I could personally see it in operation.

Given the number of requests for a narrow clean cutting flat bottom "dado" blade one would think that they would be a fairly easy find.

https://www.timbecon.com.au/torquata...ado-saw-blades a bit wider than requested

Hi P.H.

I happen to have an Opteco flat tooth grind 10" rip blade and I am very happy with it.
It has a 30mm bore but Opteco fitted a reducing bush down to 5/8".

And they are made in Australia: Circular Saw Blades Suppliers Australia | Opteco

Cheers
Yvan

Can you link to the specific blade you have on the Opteco site, Yvan. I can't see a 250mm blade on their site that fits the OP's specs. Until Mr Brush posted details of his Infinity blade I would have said that what the OP is looking for doesn't exist. The only 250mm FTG blades that I'm aware of have no more than 24 teeth, not much good for any cutting across the grain.

Originally Posted by Mobyturns

… a bit wider than requested

And only 203mm diameter.

Originally Posted by jack620

And only 203mm diameter.

true, but a viable option given there aren't many.

Have a look at the specifications for "glue line rip" saw blades and saw blades designed for composite woods as they typically use a triple chip tooth design which is closer to the OP's request. Not ideal but for limited and cautious use another option for more robust work pieces.

The request is for a very specialized and specific task that very few saw blade manufacturers would even consider supplying to due to the very limited size of the potential customer base. Look to the home of Kumiko ...

"From the beginning, I decided to do all my kumiko cutting by hand. Not because I’m some kind of Luddite, but simply because there isn’t the range of blades available in Australia that there are in Japan. At the college, the other students used a table saw and jig to cut kumiko joints, and if the design called for kumiko 5mm wide, the student would grab a blade with a 5mm kerf from the wall. If the kumiko was 2mm, a 2mm kerf blade would be fitted to the table saw. This range of blades isn’t available in Australia, so rather be limited to the standard kerf sizes of 3.2mm and 2.8mm, by hand, I have complete design flexibility with kumiko thickness." - Des King Japan Woodcraft Journeys – Kumiko | Des King - ​Japan Woodcraft Journeys – Kumiko | Des King – Japan Woodcraft Association

Originally Posted by Mobyturns

Have a look at the specifications for "glue line rip" saw blades and saw blades designed for composite woods as they typically use a triple chip tooth design which is closer to the OP's request. Not ideal but for limited and cautious use another option for more robust work pieces.

Any of the triple chip 'glue line rip' saw blades I've seen don't cut a flat bottomed groove. Mr Brush's linked blade would seem to be the best option to me, either that or see what can be sourced from Japan that is specifically made for the purpose.

My apologies Aldav, I didn't properly read the OP's need for a flat-tooth cross-cutting blade...

Cheers,
Yvan

Originally Posted by aldav

Any of the triple chip 'glue line rip' saw blades I've seen don't cut a flat bottomed groove. Mr Brush's linked blade would seem to be the best option to me, either that or see what can be sourced from Japan that is specifically made for the purpose.

In Oz there are no off the shelf options for this specific task, I've looked and no doubt many others have as well. Even if there were then there is the question about the range of desirable kerf widths available to makers.

Any thing "off the shelf" will be a compromise, so it becomes a selection process of what features of existing off the shelf blades are desirable, what are not.

No arguments from me and I realize that "glue line rip" and blades designed for composites don't produce a "flat bottomed groove" but for a regrind they would require less removal of carbide from the ATB teeth. Specific saw blades for composites like MDF are probably the closet "fit."

The best advice is to go to the saw blade experts to ask what solutions they can offer, and to review what existing makers use.

I added Des Kings comments for that purpose. He dedicated a lot of time to learning to make Kumiko and has the info from the masters, why & what they use, and why he chose his path.

Hi Folks,
thank you for your help with this.
I've certainly learned some new terms such as TCG, 4+1 etc.

The infinity will let you add to the cart but will not go past that point to the checkout.
Opteco havent replied.

Along the way I picked up the term "raker" and ended up here:

Amana 610504C 10" Prestige Electro Blu 50T Combo Blade | Carbatec

Amana 610504C Electro-Blu™ Carbide Tipped Prestige™ Combination Ripping and Crosscut 10 Inch Dia x 50T 4+1, 15 Deg, 5/8 Bore, Non-Stick Coated

It looks like the answer to me but what do others think?
Cheers