HI help with kity 419 blade

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meathead

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I am new to the forum so please go easy on me , you have heard this question a thousand times
but this the rub , I need a new blade for my kity 419, and I have searched high and low for
the best blade under £20 which will be mainly used for ripping softwood and cutting plywood, I have
my eye on Freud-Lp30M-016-8025331202178-200Mm-X-2.4Mm-X-30Mm-X-30T-General-Purpose-Saw-Blade but I am worried about the kerf regarding riving knife thickness on the kity 419 , can anyone please help before I go totally bald
I will also listen any alternative blade and issues regarding the kity rpms and blades
thanks in advance
 
measure your riving knife. From memory, it is quite thick. I previously had a kity 419 and used a freud thin kerf blade. I made a knew knife which wasn't a big job, even with no metal working skills at all. 2.4mm kerf may not be far off.

In case you don't know, the knife needs to be wider than the blade plate thickness but not as wide as the kerf. there is a faction of a mm between the two. this is so that the kerf cuts the wood. if the wood pinches, it is caught by the knife before it pinches the saw blade plate.
 
thanks for your replies . but I don't feel confident to make a riving knife just yet
I have only now taken the blade off which is long over do , another confidence thing has well
another question my rise and fall is stuck at full height and the poxy plastic wheel as lost it/s
teeth any ideas?
thanks
 
can't help with the rise and fall. probably a new part needed.

what blade is on the saw- is there enough carbide on it to resharpen? I wouldn't bother with sharpening a silver line, but if it is a reasonable blade, it will prob cost about * to have it done.

measure your knife and we can help you.
 
I had a 419 for a long time. Marcros is correct - the original blade had quite a thick kerf, and the riving knife matched it.

I bought a Freud blade, having used them on other machines (they are very good!). It was too thin and I jammed the rigving knife in the cut in the first use!

Good news! The old Axminster TS200 is a close copy of the Kity 419 (there are significant differences). The TS200 riving knife fits the 419, it is also thin enough to work with a Freud blade. Ring Axminster, explain that you want to buy a riving knife for an old-style TS200, and off you go. They are not expensive, and if you add other items to the same order it's free postage for spend of more than fifty quid.

More good news: not only does the Freud blade cut extremely well, it needs less power than the original blade (being thinner kerf'n'all), and it saves a bit of stock (cutting a thinner kerf'n'all). It's also resharpenable by any commercial saw doctor (and several times).

Slightly not good news: you might need to shim the new riving knife, but only very slightly. Here's why:

The saw blade is held in place by clamping the saw plate (the basic disc of metal) to the arbour. The teeth overhang this on both sides. That's all obvious.

The riving knife, in theory, ought to be very slightly thicker than the saw plate, but definitely no thicker than the kerf (or it will get stuck like mine did!). If it was *exactly* the same thickness as the saw plate, the geometry would be nice and easy: The mounting plate for the riving knife would line up exactly with the flat end of the arbour (where the blade itself mounts), so both metal plates, the saw plate and the riving knife, were exactly in line with each other.

To work out what you need to do, you need a vernier caliper or a micrometer, and both old and new riving knives, and old and new saw blades.

Now I need to go to my desktop machine, to draw you a diagram. But first, coffee and another piece of toast... More later.
 
Forgot to say: the "poxy plastic wheel" is a spare part from NMA, the importers. They certainly carried stock a few years ago, but Sheppach have since bought Kity, so the spares situation may have changed. The teeth are used for tilt adjustment, not rise and fall (look at tbe diagram on the front of the saw. It is a ridiculously expensive part (or it was) - just saying.

There is a strap inside that tilts the riving knife front-back as you change the blade height. This is a weak point in the design of both the Kity and the original TS200, and it can buckle if the user tries to force the blade higher than fully up. both the ones on my Kity and my TS200 were buckled when I got the saws. If buckled, it can jam the rise/fall mechanism too.

It sounds like you need to take a careful look at the innards - easiest by taking off blade and riving knife, and turning the whole thing upside down. Clamp the tilt up tight when you do this, in the straight position. The strap is a strip of steel about 3/4" wide and 5" long - if it is bent it will be obvious. It probably all needs a good clean, and maybe some grease (sparingly!) between the sliding plates and on the big leadscrew. Sawdust won't hurt, but it does encourage rust and likes grease! I haven't found a better lubricant for the leadscrew, so I am open to alternative suggestions - candle wax might be better as it isn't sticky.
 
OK, an explanation of how to sort out the riving knife:
kerf.png

I hope you can see what's going on here. The shoulder of the arbour, against which you clamp up the saw blade, is the datum (reference) surface. Ideally, the mount for the riving knife will be set very slightly to the left, as the RK is thicker than the saw plate (as I've shown it). This is a nuisance once you start swapping blades. Here are the two surfaces' alignment compared, with the RK and the blade removed for clarity:
alignment.png

The distance between the green and red lines is not a lot, but it matters. If the left edge of the new blade's kerf ends up inside the red line, the riving knife will catch, and actually promote kickback, rather than prevent it. Here's an exaggerated comparison of old (grey) with new overlaid:
old-new.png

You can see that the left edges of the two saw plates both end up in the same place, but everything else moves about! So you probably have to shim the riving knife (your new, thinner one from Axminster!), so it matches the new blade, ending up in the blue position in the last diagram.

Trying to measure those alignments on the saw will send you mad. Don't attempt it! What you can do instead is measure the blades and riving knives, with a vernier caliper or a micrometer, and do some simple sums:

Things you need to know:

1: The thickness of the old and new saw plates. Write down HALF the value and call them Sp1 and Sp2 respectively.

2. The thickness of the old and new riving knives. Write down HALF the value and call them Rk1 and Rk2.

3. The kerf each blade should cut (either written on the blade, or you can measure the width of the teeth). Write down HALF those values too, as Kf1 and Kf2.

Things you need to work out:
a. Sanity check: the new riving knife must be thinner than the new blade kerf (else don't pass "GO" nor collect 200 quid).

b. With a narrower blade, the centre-line of the whole lot moves towards the left. You need to know by how much:
Sp1 - Sp2 = X (blade centre-line shift)

c. Similarly the centre-line of your thinner riving knife also moves across:
Rk1 - Rk2 = Y (riving knife centre-line shift)

d. (the crucial bit) If Y is bigger than X, you can line up the riving knife by shimming its mounting, to get it approximately correct.

If Y is smaller, you will have to find or make a thinner spacer to replace the one on the riving knife mounting, to bring it to the correct position.

Good news: I know a lot of people use Freud blades on the TS200 without problems, so it's a safe assumption that the Axminster riving knife is thinner than the Freud blade. As for the rest, you'll have to make the measurements and work it out.

I do hope that works. If my diagrams don't help, try sketching it yourself on a bit of paper - you'll get the hang of it! And it's much easier to work through in real life than it is to explain, too.

E>
 

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but seriously thanks eric for taking the time to explain, and I will let u know if I still have all my fingers by the end of the month. but hook or crook I will give it a try
 
anyone wanna buy a kity 419. with 1 used blade and a lot of rust sliding carriage and extensions
anyone suggest a nice replacement for a kity 419 in a workshop with a limited amount of space
and a blade u don't have to make every time the thing goes'blunt!
thanks for all your help and patience
 
I guess i will try the smaller knife(have been thinking of getting a digi calipers) like eric says, just get my mrs to do the first test cut
what have u done regarding 419 blades marcros there's only so much life in one blade ?
 
I found this site Probois Machinoutils and they sell riving knifes for kity 419 with a thickness of 2.5 and they also have blades
Reference: DP22 200 30 D which is a 2.8 kerf ( no plate thickness)would this be suitable do u think? the also have 2 little holes next to bore which I don't need would this be a problem?
 
I sold my saw!

At some point you are going to want a decent blade for ripping (low tooth count) and one for cross cutting (high tooth count). I had one freud rip and a cutting solutions one which was more of a general purpose than a cross cut, but was ok on hardwood. I never used it for steel goods where it may have chipped the cut. I think that I even bought some Silverline blades at one point, against my better judgement, to see if they were any good.

It is worth getting a blade with nice big chunks of carbide on. The cutting solutions one was very good in this respect. More carbide means more sharpening before it is worn out. The cutting solutions one may cost you £20, but you will get multiple sharpens out of it. Others may cost you £15, but are virtually disposable. If you don't sharpen it, it becomes an expensive blade. silverlines are not worth sharpening, but they got me out of a bind one day!

callipers are a good investment- I find them useful for a whole manner of things. You can also use them to check the accuracy of the saw. In the meantime, look for markings on the blade you have, although they wear off. try a ruler- you may be able to see roughly what the knife and blade thickness is. Put it in the saw, and use a straight edge across the plate and see whether it clears the knife or hits it. You may even be able to hold one against the other and fee with your finger which is wider. many ways to skin a cat!
 

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