Kitty 419 table saw riving knife

[Reeva]

Hi, I’ve just purchased a Kitty 419 Table Saw, unfortunately it came without arriving knife.

I have contacted Axminster to get a TS-200 riving knife which I am told is comparable, but will have to wait approximately 20 weeks before it’s delivered.

I know it’s a long shot as my saw is relatively old, but if there’s anyone out there who would be prepared to trace their Kitty 419 Riving knife On a sheet of paper, or send a scan, including the thickness of the metal and send to me i thought I could make my own

If anyone knows where I could purchase one off the shelf in a reasonable time scale, that might be another route

Thanks in advance
Paul

 

[Steve Maskery]

20 weeks means it doesn't yet exist and is coming from China.
You can do better. Look at your saw, what is the blade diameter? The inside radius needs to be 3 -mm bigger than that. The outside diameter is cosmetic. In addition, you need to find the screw holes. Make a mock-up out of cardboard. Then refine it. Them make it out of MDF. Then refine it. When you are happy that it will be right, buy some gauge plate of the appropriate thickness for your blade (thicker than the plate, thinner than the kerf, but you knew that already, I guess), and make it to that pattern.
Half a day v 20 weeks
S

 

[Dibs-h]

Hi, I’ve just purchased a Kitty 419 Table Saw, unfortunately it came without arriving knife.

I have contacted Axminster to get a TS-200 riving knife which I am told is comparable, but will have to wait approximately 20 weeks before it’s delivered.

I know it’s a long shot as my saw is relatively old, but if there’s anyone out there who would be prepared to trace their Kitty 419 Riving knife On a sheet of paper, or send a scan, including the thickness of the metal and send to me i thought I could make my own

If anyone knows where I could purchase one off the shelf in a reasonable time scale, that might be another route

Thanks in advance
Paul

Daft question perhaps but it's been a while since I've been in the shed - is the riving knife easy enough to remove? My 419 is sat in the shed.

Assuming it isn't a right ball ache to remove - could do it it tomorrow and send you a scan.

HIH

Dibs

 

[rafezetter]

It's not a ball ache to remove - but I can do you one better, mine is currently out of the machine, I could take a photo of it set against some graph paper, as I don't have a scanner to give you a 1:1 version.... hang on... *rummage*, wait no..... *mumbles* why do I keep buying copier paper from the pound shop.. I don't even have a copier.

aha!

hold that thought.

clikken ze pikture.

graph paper is 2-10-20 which means each small square is 2mm, each BOLD square is 20mm.

in reality is doesn't actually need to be that complex shape, top and bottom can be co-planar (bottom of the mounting point doesn't matter what shape it is) and if the back was also vertical that wouldn't matter either if you don't have the extraction cover, which is next to useless anyway and gets in the way.

All you really need to make sure of is the curve at the front and the distance of said curve away from the mounting slot - if you make it larger than this it will hit the blade when mounted, but smaller would be OK.

Thickness 3.2mm bang on.

But that's relative too - this only equates to the the thickness of the blade it came with factory fitted - if you have that, fine, if not then check the kerfs of your various blades - they do vary and if the riving knife is thicker than the blade it can cause issues (so I'm led to beleive) - thinner and it will allow the back of the blade to catch the work and throw it anyway.

To do it's job properly a riving knife needs to be EXACTLY the same thickness as the kerf of the balde you are using - finding gauge plate (preferred material for this) might be a bit harder than you think - because I've looked myself for a 2.8mm thick sheet for my thinner kerf freud blades .

You're going to need some calipers if you don't have already.

 

[Steve Maskery]

I think that many of us wold disagree slightly with that last statement.
The RK should be thicker than the plate of the blade, and slightly less than the kerf itself.
Sp for a 1/8" kerf (which is 3.2mm), a 3mm RK is usually pretty close to perfect.

The problems get trickier for thin-kerf blades. The RK needs to be thinner, of course, but that also makes it less stiff and so more vulnerable to being bent and causing interference with the cut.

S

 

[rafezetter]

I think that many of us wold disagree slightly with that last statement.
The RK should be thicker than the plate of the blade, and slightly less than the kerf itself.
Sp for a 1/8" kerf (which is 3.2mm), a 3mm RK is usually pretty close to perfect.

The problems get trickier for thin-kerf blades. The RK needs to be thinner, of course, but that also makes it less stiff and so more vulnerable to being bent and causing interference with the cut.

S

I thought the point of the riving knife was to stop the teeth of the blade catching the work and throwing it at you, if the plate is thinner than the teeth (kerf) then that would allow the teeth at the back of the saw blade to engage with the wood? At the very least it would allow the teeth at the back to score the cut if the wood wants to close up behind the blade.

I certainly wouldn't presume to correct you Steve, but what you said doesn't really fit with what I thought the riving knife was for.

I'm going to need to make a thinner RK for my 2.8mm blades so if you could elaborate further on your statement I'd appreciate it.

 

[Lazurus]

topic114526.html

Similar thread with pictures

 

[Steve Maskery]

if you could elaborate further on your statement I'd appreciate it.

You are quite right about what the RK is for and how it works. But when I say slightly less than the kerf, I mean slightly. A couple of thou. Just clearance. The RK is immediately behind the teeth, no more than 8mm away, and the RK itself is what, shall we say 40mm ish deep, so to catch the teeth the wood would have to bend in very severely indeed.

If there were no clearance then the workpiece would bind as the kerf and the RK would be a size-for-size fit. That would make pushing hard, running the risk of forcing it, slipping and running the risk of an accident. The risk is even greater if the blade is even the slightest bit out of perfect alignment.

You must have clearance - the thickness of a piece of paper would do, but in practice we are governed by available stock sizes. So 3mm for a 1/8" kerf works well.
For a thin-kerf blade, 3/32" is suitable for anything where the plate is less than 2.3mm.

HTH
S

 

[That would work]

Imagine if the RV was exactly the same as the kerf you would likely be having to push timber through with some force which would be dangerous in itself.

 

[Reeva]

Hi, I’ve just purchased a Kitty 419 Table Saw, unfortunately it came without arriving knife.

I have contacted Axminster to get a TS-200 riving knife which I am told is comparable, but will have to wait approximately 20 weeks before it’s delivered.

I know it’s a long shot as my saw is relatively old, but if there’s anyone out there who would be prepared to trace their Kitty 419 Riving knife On a sheet of paper, or send a scan, including the thickness of the metal and send to me i thought I could make my own

If anyone knows where I could purchase one off the shelf in a reasonable time scale, that might be another route

Thanks in advance
Paul

Daft question perhaps but it's been a while since I've been in the shed - is the riving knife easy enough to remove? My 419 is sat in the shed.

Assuming it isn't a right ball ache to remove - could do it it tomorrow and send you a scan.

HIH

Dibs

Hi Dibs, that would be great, thanks

 

[Reeva]

It's not a ball ache to remove - but I can do you one better, mine is currently out of the machine, I could take a photo of it set against some graph paper, as I don't have a scanner to give you a 1:1 version.... hang on... *rummage*, wait no..... *mumbles* why do I keep buying copier paper from the pound shop.. I don't even have a copier.

aha!

hold that thought.

clikken ze pikture.



graph paper is 2-10-20 which means each small square is 2mm, each BOLD square is 20mm.

in reality is doesn't actually need to be that complex shape, top and bottom can be co-planar (bottom of the mounting point doesn't matter what shape it is) and if the back was also vertical that wouldn't matter either if you don't have the extraction cover, which is next to useless anyway and gets in the way.

All you really need to make sure of is the curve at the front and the distance of said curve away from the mounting slot - if you make it larger than this it will hit the blade when mounted, but smaller would be OK.

Thickness 3.2mm bang on.

But that's relative too - this only equates to the the thickness of the blade it came with factory fitted - if you have that, fine, if not then check the kerfs of your various blades - they do vary and if the riving knife is thicker than the blade it can cause issues (so I'm led to beleive) - thinner and it will allow the back of the blade to catch the work and throw it anyway.

To do it's job properly a riving knife needs to be EXACTLY the same thickness as the kerf of the balde you are using - finding gauge plate (preferred material for this) might be a bit harder than you think - because I've looked myself for a 2.8mm thick sheet for my thinner kerf freud blades .

You're going to need some calipers if you don't have already.

Many thanks rafezetter for posting, if all fails I have this for reference

Paul

 

[Lons]

Interesting stuff never stop learning.

Much of the wood I've ever cut on a table saw moves as stress is relieved by the cut and if the movement happens to be inwards it could be dangerous and I always thought that the main reason for a riving knife is to stop the wood binding behind the saw blade which would then catch and kick back.

Maybe my timber isn't as dry as it could be.

 

[Eric The Viking]

Interesting stuff never stop learning.

Much of the wood I've ever cut on a table saw moves as stress is relieved by the cut and if the movement happens to be inwards it could be dangerous and I always thought that the main reason for a riving knife is to stop the wood binding behind the saw blade which would then catch and kick back.

Maybe my timber isn't as dry as it could be.

It's not dryness as such.

Imagine you had to construct the branch-to-trunk joint of a heavy bough from steel, rather than it growing naturally. Imagine the bending forces that have to be counteracted.

The trunk immediately above (and the top part of the bough) will be in considerable tension, but the underneath of the bough and the trunk below in considerable compression. Trees rarely have natural diagonal braces, except right at the bottom of the trunk sometimes*, although branches rarely come straight out from the trunk horizontally.

Think of the wood as "pre-tensioned" (or pre-compressed) in order to cope with the forces in play. And just as with the suspension wires of a bridge, cutting through those fibres isn't without consequence.

I acquired a large lump of oak recently as salvage. It was used as a squared-off beam and it's about 6" x 6" x 40". There's a lovely grain pattern because it's crotch wood, but it's going to be really hard to use, because it's springy in loads of directions, and already has "interesting " shakes. I'm still not quite sure how I to use it.

E.

*I did once hide from a charging male Asian one-horned Rhino behind such a tree, in a rainforest in Nepal. I didn't really notice what species the tree was, but the big roots started to spread out from some feet above ground, giving them the appearance of rocket fins. Thankfully, rhinos are rather short sighted, and after pawing at the ground like a horse and snorting a lot, only a few feet away, it got bored and lumbered off in the other direction. I took pics but there was rather a lot of camera shake...

 

[Lons]

Thanks Eric, I intended to put an emoji behind that as it was tongue in cheek and I know why there is stress however that is an informative post especially for any newbies out there who probably have no idea it exists. =D>

Sounds like a really nice bit of oak. The trouble with those in my case is that I can never think of a worthy project so gets stored away until I can when realistically I know i probably never will.

I had an encounter with rhinos in SA though I think they were juveniles and I had somewhere to hide. We were in a safari truck, just me and the missus with the driver and the thing broke down on a dirt track with high verges. The two of us heads under the bonnet while the missus kept a look out from the high seats, managed to get it going and just climbing into the truck when 3 rhinos came running out of the undergrowth and had a go at the front bumper, did a bit of damage but were surprisingly quick.

Had another with a bad tempered bull hippo and one in Canada where I probably got too close to a very large Grizzly. :roll: