Thread: Diablo 184mm & 254mm 40t body width & riving knife width for table saw?

Just to be precise, here are the two blades I am considering:

Diablo 40t 184mm: Diablo Tools | 7.25"/184mm 40T Fine Finish CORDLESS

Diablo 40t 254mm: Diablo Tools | 10"/254mm 40T General purpose CORDLESS

Can't help you with the thickness of the blade body, but I'd be inclined to go with the 2mm kerf version rather than 1.55mm. Either will be an improvement over the 2.8mm kerf standard (saw won't have to work so hard). but 1.55mm really is a bit too fine. Plate of the blade is likely to be around 1-1.2mm for this kerf, and I think you'll find the whole thing flexes too much in use. Ultra thin kerf blades are more of a specialty thing, and most makers suggest they are used with stabilising discs to prevent flex/wobble when cutting. On the other hand, a 2mm thin kerf blade should be able to cut full depth without any such concerns.

I should add, once you know the kerf and plate thickness of a blade, I always make the riving knife the average of these two measurements (i.e. midway between them). My homemade riving knives are timber (easily sanded to whatever exact thickness required), but it doesn't take much work with a file to make a suitable metal version? You only have to do it once.

Thanks for those helpful thoughts, Mr Brush.

If I go with the 2mm kerf blade, perhaps the stock 2mm riving knife could work if I took the enamel paint off it? On my bench grinder, or some other way?

I'm thinking maybe the bench grinder would be too aggressive and produce an uneven result in thinning the stock riving knife.

A look through the Bunnings catalogue has given me this idea:
Step one - paint stripper, perhaps this: https://www.bunnings.com.au/poly-250...ipper_p1715058
Step two - I have a plastic abrasive drill brush to clean it up
Step three - put some metal sanding paper on my sander, perhaps this: https://www.bunnings.com.au/flexovit...sheet_p1210440

I'm thinking that should give an even result, but I have no experience in either stripping paint or sanding metal. Sound okay?

in general there are at least 2 standard widths for the kerf of power saw blades

Standard kerf = 1/8" (= 3.175 mm)
Thin kerf = 3/32" (= 2.38125 mm)

Now, I'm not sure what kerf width is used by battery powered saws BUT I suggest that blades designed for those saws should not be fitted to a 240 V powered table saw.

My guess is that your Ozito is designed to use a standard thin kerf blade.

It would seem you are right Ian. The question is whether I can safely modify that design. Is the riving knife the only element of the design that would need to be changed to accommodate a 2mm or thinner kerf blade, or might there be other aspects I would need to consider? Would it be best to stick with the original blade diameter for this reason, even if I use a thinner blade and riving knife, to avoid hidden problems?

Now I look at the fine print, the Diablo website says the 254mm 40t blade is "an excellent choice for a table saw", but doesn't mention "table saw" in the uses of the 184mm blade. Looks like they agree with Mr Brush.

I should note that I'll be using the table saw primarily for ripping and crosscutting pretty hard wood, with the softest being woods like Queensland Maple, through to Red Mahogany and Gidgee. The end result will hopefully be some nice Celtic whistles

[QUOTE=Now, I'm not sure what kerf width is used by battery powered saws BUT I suggest that blades designed for those saws should not be fitted to a 240 V powered table saw.

[/QUOTE]
Hi Ian
When you look at the sawblades they say corded & cordless so i am thinking they are trying to jump on the bandwagon of the cordless rage happening at the moment and they are their standard blades
Cheers Rod

Why do you want to go with a blade with a kerf thinner than the standard blade? The 10" blade you've linked to seems to be specifically marketed to those using a battery powered tool. With them it's all about saving battery power rather than providing the best cutting compromise. 2mm is just too thin for a 10" blade. There is no information on the geometry of the teeth on that blade, but from what you can see from the picture they don't appear to have much hook, if any.

IMO you would be far better off with this blade (2.5mm kerf) - Diablo Tools | 10"/254mm 50T Combination or the Freud equivalent, the Fusion P410 thin kerf (2.3mm kerf) - Freud Tools | 10" Thin Kerf Next Generation Premier Fusion General Purpose Blade. There are people on here who use the P410 and swear by it.

Thanks aldav. The reason I want a thin kerf is that a couple of mm may mean the difference between getting 3 or 4 whistle bodies, or 5 or 6 mouthpiece blocks, out of a certain width of board. When the wood is hard to get like Gidgee or Burdekin Plum you want to make the most of it. Nevertheless, safety is really my number one consideration, so I will buy a thicker kerf blade if necessary. Certainly the 2.5mm kerf blade you mention would be easy to fit on my table - no modification needed to the riving knife. The Fusion blade you link to looks perhaps hard to sharpen with its multiple facets on the cutting edges?

I just looked up the specs for the 10" blades I have run on my JET ProShop saw. I initially had a standard 3.2mm kerf, then went over to a thin kerf (0.097" = 2.46mm) combination blade. Since the combination blade does both ripping and crosscutting very well indeed, it now lives on the saw. This means only one riving knife thickness to worry about.

Of course, if you're trying to minimise wastage, you'd break stuff down with a bandsaw rather than a tablesaw. Coincidentally, if you're only working with smaller bits of expensive timber, Aldi have a baby bandsaw this week for not much more than the price of a good quality combo blade for your tablesaw.

https://www.aldi.com.au/en/special-b...ps/p/band-saw/

Quality will be nothing to write home about, but it would probably do the job with minimal wastage.

The benefit of a thinner kerf blade on a moderately powered tablesaw is that you can cut thicker/harder stock with less bogging down of the motor. I noticed this straight away, and wouldn't go back to running any standard kerf blade on my JET after trying the thin kerf versions. I have Infinity combo blades, but if I were buying locally (i.e. without the hassle of ordering from the US) I'd get the Freud Fusion P410 combo in thin kerf if I had to buy one today.

Originally Posted by nosnow

Hi Ian
When you look at the sawblades they say corded & cordless so i am thinking they are trying to jump on the bandwagon of the cordless rage happening at the moment and they are their standard blades

hi Rod
I have a cordless Hitachi saw. The blade it uses is definitely thinner than that on a regular powered circular saw

Thanks very much for all the helpful posts.

Ended up buying the Diablo blade recommended by aldav - thanks -- Diablo Tools | 10"/254mm 50T Combination. I hear what you're saying about a bandsaw Mr Brush - unfortunately in Townsville I'm about 800km from the nearest Aldi store in Gladstone. Best I could do in Townsville would be the $299 Ryobi bandsaw from Bunnings, which is a bit beyond the budget right now.

What might work better would be getting a cheap 184mm circular saw with a very thin kerf blade and using that for the pieces where the kerf width is significant, which will probably be the minority. The table saw will be quicker and easier with most of the cutting I do. The Bosch 184mm circular saw is only $89 at Bunnings and the $40 Diablo blade I could put on it (the one from my original post) is 1.55mm kerf. That's within the budget and would take less space than a bandsaw in my small workshop area.

The final issue I have with the table saw is that the blade and riving knife don't exactly line up. That's not because I've changed the blade, as it's the same body width as the stock blade - 1.8mm. It's about 0.2mm out. I'm going to try shimming the blade between the axle plate and the inner flange. Found some 0.1mm shims the right size on ebay which will take about a week to get here... patience.