Riving knife thinner than blade kerf

[clarkey2016]

Hi guys,

First time here, apologies it this has been covered to death (yes, I did check first).

I recently purchased the DeWalt DW745 table saw, but wondered if anyone could answer a question I had (the retailer has gone v.quiet):

The manual clearly states that the total blade kerf must not exceed the thickness of the riving knife. The RK is 2.3mm, yet the blade kerf is 3.0mm.

Does anyone her have this model with the factory blade and can confirm? How is this possible?

Thought I'd see if anyone else could help before waiting ~3 weeks in a queue with DeWalt.

Thanks guys!

 

[marcros]

the riving knife should be between the thickness of the saw blade plate and the thickness of the kerf. this is so that if the wood moves as you cut, it cannot pinch on the saw blade plate.

if you measure the blade plate, you will be able to see whether it is suitable- it should be a little less than 2.3mm- say 2.0/2.1mm etc.

Riving knives are easy to make at home should you need to. As you use the saw more, you may need a couple of different ones anyway, depending on what blades you have.

 

[marcros]

welcome to the forum by the way!

 

[clarkey2016]

Hi Marcros,

Ahh - I think I've completely mis-read that then. So, essentially the blade kerf shouldn't matter as long as the body is less than the RK (and the kerf is wider).

Great, thanks! Looks like I can go for the Freud blades after all

 

[marcros]

i think that the idea is that the teeth will cut through (ie the kerf width) and the body will have a gap maintained by the RK.

If you turn the situation around, if the RK was wider than the kerf, as soon as the RK entered the cut you wouldnt be able to proceed- if RK was 3mm and kerf 2.5mm, you would have a 3mm RK trying to enter a 2.5mm gap!

 

[Lons]

i think that the idea is that the teeth will cut through (ie the kerf width) and the body will have a gap maintained by the RK.

If you turn the situation around, if the RK was wider than the kerf, as soon as the RK entered the cut you wouldnt be able to proceed- if RK was 3mm and kerf 2.5mm, you would have a 3mm RK trying to enter a 2.5mm gap!

I had exactly that when I fitted a thin Freud blade to my SIP 01332 and it's downright dangerous. Could push it through at risk of fingers or splitting the wood but as I haven't got around to making a new RK yet I can't use the blade.