Proxon KS230 splitter blade jams

Hi, I'm curious, why the splitter blade jams against the copper clad Phenolic PCB material I'm cutting, I can only think the fence is not parallel to the saw blade.

The cut itself is clean but the sheet always ends up hitting the splitter blade - I'm using the 28.020 blade it cuts 50x0.5 fiberglass with ease.

I do have other blades 28.011: 50x0.55 Carbide blade for cutting fiberglass. 28.014: 58 x0.5 Soft, hardwood and cross cut. For curiosity I have a 28.014: 58.05 for soft/ hard wood and cross cut - this worked like a charm on Phenolic but not tried on on fiberglass yet, it gave a wider cut.

I do know taking the splitter off is alright if ya wanna loose fingers, I wanna be keeping mine thanks. I've not tried the other blade yet, the more I think, the more tangled I get, has any one any clue whats going on? Thanks,

Dave.

Splitter blade? Riving knife, perhaps?

Is the cut parallel to the fence? Shim, if not?

Likely better to make, and use, a feed-in device so fingers are never put at risk close to any cutting blade.

.

“Splitting wedge” according to Proxxon

27006 - 71

MichaelG.

.

http://www.proxxon-tools.com.au/downloads/manuals/27006%20KS230.pdf

Edited By Michael Gilligan on 19/03/2020 22:37:47

Or "cotter"!

Yet another example of a German manual translated by a non-native speaker of the target language.

Out of curiosity, I’ve just translated “splitting wedge, splitting cotter, riving knife” into German, using DeepL ... it produced “Spaltkeil, Spaltkeile, Spaltmesser”

I wonder which, if any, of those words features in the German instructions.

Can’t be bothered searching tonight though.

MichaelG.

I will just add that I admire the Germans for putting their own language at the head of the long list that accompanies this kind of tool.

I don't know anything about Proxxon saws or blades Sparks...

But one reason this happens on a table saw, is that if you change the saw blade and the new blade is narrower than the one it's replacing - then the work will probably hit the riving knife if that's not also changed - as the riving knife should be the same width as the saw blade. The cut in the wood will be narrower and it will hit the front of a wider riving knife.

I now generally use thinner Diablo framing saw blades (1mm cut) and I had to make a new riving knife for my table saw to solve this problem. The other reason of course is that the knife is not exactly aligned with the saw blade for some reason...

Regards,

IanT

Can’t be bothered searching tonight though.

Neither can I. It is a riving knife to me. A bit smaller than the one on the large Wadkin rip saw I have used or even my little 9”(?) radial and bench saws at home. I wouldn’t get my fingers anywhere near a rotating blade, even though the riving knife might have been removed for some jobs.

IanT's point about the thickness of the riving knife is mentioned in the manual from which it also appears that the knife does not conform closely to the radius of the blade. No doubt Proxxon have their reasons for this but it may be contributing to the problem.

Having just watched the video, linked on this page: **LINK**

https://www.proxxon.com/en/micromot/27006.php

Whatever we choose to call it ... the ‘splitter’ looks to be a rather unusual design

MichaelG.

Posted by IanT on 19/03/2020 23:42:42:........The cut in the wood will be narrower and it will hit the front of a wider riving knife.....

Thanks Ian, that's what's happening, when I tried on a soft/hardwood cross cut blade 28-014 it worked every time, since I have two of these I decided try it on small piece of fiberglass knowing it would probably ruin it.... it did after the first attempt much to my amazement, started to struggle half way through, and I'm letting the saw do the work.

For any sort of Cotter/splitter' it does seem flexible somewhat but I don't think this is an issue, I thought these things were suppose to be rigid. I've measured the fence to the blade, the Cotter thingy mi' bob seems to be aligned with the blade. There's no problem in cutting until the edge hits the Splitter. Thank you for all the responses.

Maybe I ought try a wet tile cutter or splash out on a guillotine that cost three arms and two legs to buy.

Dave

I bought one of these saws several years ago to cut up small ABS plastic strips where I worked.

I had exactly the same problem where the plastic jammed against the blade and the guide making an awful sound and welding the plastic to the blade and giving a vicious kick back to my fingers.

I spent a morning stripping it down and fixing it. I found that the motor assembly was not square to the table which I managed to adjust, and also I had to take a file to the adjustable guide as that was also not square to the table.

My advice is to reject it back to the supplier if you can.

I was very disappointed with the poor quality of it considering how much it cost.

Bruce.

Hi Bruce, The blade seems right so I guess the motor mounting is. I got a Proxon TBM220 mini bench drill here the first one I got the base wobbled like clappers - anything but flat, I gotta say they sent me a replacement drill and was here the very next day and they collected the 'wobbly' so I'm not grumbling here

A little bit of thought I think is needed with Proxons I have-:

The KS220 saw, I reckon the Cotter or splitting wedge as Proxon describes it ought to be rigid rather than springy, wished I'd bought the bigger version now.

The TBM220 mini drill works mighty fine for PCB work again it could be improved by fitting a fan, you are only suppose use it 10 minutes on and 10 minutes off, after about 15 minutes mine gets mighty warm AND a little LED light in the base would be dandy, I do have plans on putting a light in the space underneath, I do think that was initially for as it looks like a lens will clip in.

Dave.

Maybe grinding a chamfered lead-in edge on both front edges of the splitting wedge / cotter / riving knife might keep stock from getting hung up on it.

The other thing worth a look at is to check the table flatness. I used a cheap table saw with a plastic top once and the centre at the blade was in a depression in the table. Table was nowhere near flat and not very rigid. If the stock was held down to the table it bound the saw after the cut as the cut was closing up. If your table has a depression maybe you could hold the stock at the outer edges, or wedge the centre level from underneath to keep the cut from closing up. Just food for thought.

If the width of the saw is close to that of the splitter, (riving knife), then blade wear will reduce the amount of set in the teeth, assuming it is an all steel blade, and it could rub. The particular plastic may have a tendency to bow inwards reducing the gap originally cut by the time it reaches the splitter. Carbide tips on blades are always wider than the disc and are unlikely to wear at all.

You could probably make a cantilever support for the guard and do away with the splitter altogether, or make the splitter thinner if it didn't have to provide support for the guard.

Yes I had that thought of grinding the outer edge of the lead in, that ought to help guide the 'wotsits' into the cut, I've checked everything I can think off.

@Old Mart

Now there's a point, with this specific blade Proxon 28-020 the cotter fits in the cut with no play at all, when using the incorrect blade 28-014 which has wider teeth I get no problems and there is play of the cotter blade in the cut... I have two of these blades so I tried one on fiberglass board - it ruined the blade in two cuts! I knew it would but didn't expect it so quick, this blade is for soft/ hard wood and cross cuts.

Should there be play in the cut?

Dave

From my days of using a bench mounted wadkin circular saw, the riving knife had to be ridgid and set close to the back edge of the blade, a little thinner than the cut being produced was ok so long as it wasn't much and the two faces either side of the new cut could not come together and throw the work back out at you !

Back in the late sixties, my firm was making printed circuit boards for mainframes. We cut them on a Wadkin circular saw which used 2 foot diameter blades. Tungsten carbide tip blades were the minimum spec for cutting fibreglass, and we bought a diamond blade which was steel with a vitreous diamond periphery of about 1/8" deep by 3/32" wide. That was superior for fibreglass, but no use for phenolic boards as it clogged up and had to be painstakingly cleaned with a little brass brush. The diamond was much safer to use as it would burn the fingers rather than cut them off if you touched it.

Steel saws will wear out immediately they are used on fibreglass. Also be aware of the dangers of breathing in the dust and use a vacuum cleaner and mask.

Thanks Old Mart, I do have a Tungsten Carbide blade... I thought I'd tried it, it still looking intact in the seal, "Whoooa Davy lad, owd thi reigns lad", now that's 0.55 thick, slightly thicker than the problematic one - better try that and prompt, dunno what the cut is like but we'll be finding out.

I can get a diamond blade for the KS230 but very seldom use fiberglass, I do use it once in a while for VHF circuitry and the odd power supply, I use the cheaper stuff mainly, paper resin or phenolic.

Dave