# DIY Zero Clearanace Throat Plate: Riving Knife Slot for Dewalt 744XRS?



## 5x10 (Feb 14, 2013)

I'm working on making my first zero clearance throat plate for my first table saw. (Dewalt 744XRS) I'm a total noob; didn't even know what/why these were for until the other day.

I'm running into two issues so far:

1. The blade won't retract far down enough to allow me to drop the new insert in at all. *Do I need to buy a smaller blade to start the cut, or is there another way?*

2. I'd love to continue using the riving knife and blade guard assembly; *is there a trick to cutting the slot further back to allow the riving knife through?* (I'm considering flipping it over to extend the length of the cut w/o cutting all the way back.)

My progress so far:


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## smokie (Dec 29, 2012)

I took the blade of my circ saw (7 1/4" blade). Installed it and lowered it, put my insert in place. Slid my fence over the plywood insert. Started the saw and raised the blade. Be real careful where you put the fence. You don't want the blade to come up into the fence. As far as the riving knife is concerned. Figure out how much extra length you need on the slot to accept the knife and cut that out with a jig saw. Hope this helps.


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## 5x10 (Feb 14, 2013)

Thanks Mark, I went to the BORG and bought a cheap 7 1/4" blade, placed the fence as you suggested (carefully) and raised the blade as far as it would go to get the kerf slot started. That worked great.

I was able to use a jigsaw to extend the slot for the riving knife, but I wound up having to cut all the way through it, since the thru-cut position on the riving knife needed the full clearance in the back when fully raised.










Since this is only plywood, I'm now concerned about structural integrity and binding on the blade, but will do some careful testing.

I think maybe I now know why the Leecraft aftermarket throat plates for the DW744 and 745 have a disclaimer re: the Dewalt factory splitter/guards as being incompatible with these plates.

http://www.forrestsawbladesonline.com/product_630_Leecraft_ZeroClearance_Table_Saw_Insert_139_16L_x_33_4W_DeW.html


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## smokie (Dec 29, 2012)

5×10. I'm thinkin' if you've cut all the way through on one end you can't have much strength in that insert. You don't want to be any where around there if that plywood breaks and catches the blade. If there is a PROPER after market insert, spend the money. Safety first. Saving a buck second.


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## huff (May 28, 2009)

5×10,

How often do you have to raise the blade to it's fullest height? I found that when I made my zero clearance insert, I made the slot long enough that I could raise my blade and riving knife at least 1 1/2" and that left plenty of stock left at the end of my insert for strength.

I found I really don't cut stock that thick that I need to raise my blade to it's fullest height, but when I do, I simply switch back to my regular insert.


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## 5x10 (Feb 14, 2013)

@Mark, I needed to hear that. Tossing that one in the scrap pile and starting over. I made a few more blanks last night, but I may buy at least one after market insert for comparison.

@huff, #headsmack! I can't believe I didn't see that, great point! I haven't made enough cuts on the saw yet to have really thought that through; sounds obvious now that you've spelled it out for me. Thanks so much for pointing that out.


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## MarkDavisson (Apr 26, 2009)

5X10, here's an alternative that you may or may not like: http://www.microjig.com/products/mj-splitter/


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## Quanter50 (Feb 11, 2012)

Here is a riving knife I made for my homemade zero clearance insert. I used a piece of walnut and a piece of aluminum road sign. I made this to use with the thin kerf blade. Works great.







:


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