Non-Thru-Cut Riving Knife

algale · Post by **algale** » Fri Sep 20, 2013 7:37 pm

Mine also measure .075 inches. Seems like that's the standard they used.

JPG · Post by **JPG** » Fri Sep 20, 2013 7:49 pm

14 Gauge sheet metal!;)

dusty · Post by **dusty** » Fri Sep 20, 2013 8:47 pm

[quote="JPG40504"]14 Gauge sheet metal!]
I made mine using aluminum and if I remember correctly it was 11 gauge. In my opinion, .075" is too thin and especially if using other than a thin kerf blade.

I was trying to make it wedge shaped with a max thickness just a tad less than a typical thin kerf blade (.093"). All that I need to avoid is having it thick enough to obstruct the free movement of the wood as it meets the spitter. It also cannot be thick enough to impede the movement (wedge the wood) as it moves toward the outfeed end of the rip fence.

If it binds, using it would be more hazardous than doing without a splitter all together.

FWIW: http://www.engineersedge.com/gauge.htm http://www.unc.edu/~rowlett/units/scales/sheetmetal.html

JPG · Post by **JPG** » Fri Sep 20, 2013 11:18 pm

dusty wrote:I made mine using aluminum and if I remember correctly it was 11 gauge. In my opinion, .075" is too thin and especially if using other than a thin kerf blade.

I was trying to make it wedge shaped with a max thickness just a tad less than a typical thin kerf blade (.093"). All that I need to avoid is having it thick enough to obstruct the free movement of the wood as it meets the spitter. It also cannot be thick enough to impede the movement (wedge the wood) as it moves toward the outfeed end of the rip fence.

If it binds, using it would be more hazardous than doing without a splitter all together.

FWIW: http://www.engineersedge.com/gauge.htm

I would have 'guessed' 13 Ga.]http://www.unc.edu/~rowlett/units/scale ... metal.html[/url]

BuckeyeDennis · Post by **BuckeyeDennis** » Sat Sep 21, 2013 6:49 am

When using a Shopsmith blade with a 0.094" (3/32") kerf, it seems to me that 0.075" is about as thick as I'd want to go on the riving knife. Even if everything is perfectly straight and aligned, that would leave less than 0.010" clearance on each side of the knife.

With the riving knife mounted to the lower blade guard, and the guard re-clamped to the quill on every setup, I find it difficult to achieve perfect and repeatable alignment. Based on the above, if I'm misaligned by more than 0.010", the riving knife could catch the leading edge of the workpiece, and/or push it sideways and make the rear teeth of the blade engage on the upcut.

dusty · Post by **dusty** » Sat Sep 21, 2013 7:34 am

BuckeyeDennis wrote:When using a Shopsmith blade with a 0.094" (3/32") kerf, it seems to me that 0.075" is about as thick as I'd want to go on the riving knife. Even if everything is perfectly straight and aligned, that would leave less than 0.010" clearance on each side of the knife.

With the riving knife mounted to the lower blade guard, and the guard re-clamped to the quill on every setup, I find it difficult to achieve perfect and repeatable alignment. Based on the above, if I'm misaligned by more than 0.010", the riving knife could catch the leading edge of the workpiece, and/or push it sideways and make the rear teeth of the blade engage on the upcut.

I am confident that many (if not most) users will agree with you on this but I am not satisfied with the performance of the production splitter (.075" thick).

I believe there are better ways of achieving what this splitter is suppose to do for us and I am working on a solution. Because it is a safety issue, I will not post any details until I am satisfied that I either have a solution or that no improvement is available.

Shopsmith is obviously satisfied with the current splitter as it has not changed since the upper saw guard was introduced.

algale · Post by **algale** » Sat Sep 21, 2013 10:02 am

dusty wrote:I am confident that many (if not most) users will agree with you on this but I am not satisfied with the performance of the production splitter (.075" thick).

I believe there are better ways of achieving what this splitter is suppose to do for us and I am working on a solution. Because it is a safety issue, I will not post any details until I am satisfied that I either have a solution or that no improvement is available.

Shopsmith is obviously satisfied with the current splitter as it has not changed since the upper saw guard was introduced.

Dust,

Can you expound a little on what problems you have found with it and are you referring to (1) the non-through cut riving knife, (2) the upper saw guard splitter, or (3) both?

I have been satisfied with the non-through cut riving knife but when the same thickness is used in the upper saw guard splitter, I have been dissatisfied because the leverage or forces of the added weight of the blade guard can easily twist the splitter, especially on bevel cuts.

For this reason (and because the anti-kickback pawls on my upper guard were sticky and then popped off when I tried to adjust them per customer service's instructions), I have been using only the non-through cut riving knife for all table saw cuts for the last several months. I know this means I missing out on some safety features, but I have been satisfied with the riving knife's performance.

I will look forward to seeing if you are able to develop something better.

Al

dusty · Post by **dusty** » Sat Sep 21, 2013 11:14 am

algale wrote:Dust,

Can you expound a little on what problems you have found with it and are you referring to (1) the non-through cut riving knife, (2) the upper saw guard splitter, or (3) both?

I have been satisfied with the non-through cut riving knife but when the same thickness is used in the upper saw guard splitter, I have been dissatisfied because the leverage or forces of the added weight of the blade guard can easily twist the splitter, especially on bevel cuts.

For this reason (and because the anti-kickback pawls on my upper guard were sticky and then popped off when I tried to adjust them per customer service's instructions), I have been using only the non-through cut riving knife for all table saw cuts for the last several months. I know this means I missing out on some safety features, but I have been satisfied with the riving knife's performance.

I will look forward to seeing if you are able to develop something better.

Al

As state in the previous post, because it is a safety issue, I will not post any details until I am satisfied that I either have a solution or that no improvement is available.

I have no problem at all keeping the item being cut against the fence on the input side of the blade. A properly located feather board insures that. On the output side, because I cannot use a feather board, I sometimes have the material move slightly into the blade.I need something that will do what a feather board would do for me if it was located on the out feed side of the blade. That is - keep the material being cut from moving away from the fence. Note: This movement, when it occurs, is one of the things that contribute to a kick back).

Splitters being used on other table saws solve this problem but because the Shopsmith splitter is a function of the upper saw guard and because its' location moves with the quill (the spindle), they do not work so well with the Shopsmith.

greitz · Post by **greitz** » Sat Sep 21, 2013 8:40 pm

"I need something that will do what a feather board would do for me if it was located on the out feed side of the blade."

Dusty- have you thought about "board buddies"? The Rockler picture shows them being used on both infeed and outfeed sides of the blade. Sorry, no personal experience with them, but I think someone on the forum recommended them a while back.

http://www.rockler.com/product.cfm?page=11262

Gary

algale · Post by **algale** » Sat Nov 16, 2013 9:09 pm

I think we've pretty well established at the outset of this thread how thick the non-through cut riving knife is: 0.075 inches.

You'd think that the non-through cut riving knife would be the same thickness as the riving knife built into the upper guard, right? I assumed it was. Until I measured mine. On the upper guard I am showing 0.073 inches. Curious if anyone else gets the same reading on the upper saw guard riving knife. I have always though the upper saw guard riving knife was a bit too twisty. Could that 0.002 difference be the cause?