Scoring blade

[Giff]

I have been having trouble with a scoring blade on my table saw ( Record TS315). I have been ripping 12mm & 9mm birch
ply and it splinters really badly. In fact it is better not using the scoring, but still not a clean cut.
I have been cross cutting the same sheets with little tear out, and ripping full sheets with a Festool TS55
with a clean cut. Any tips for depth on blade or something to check. Geoff

 

[custard]

If you're really sure it's set up correctly then maybe your scoring blade needs sharpening.

Personally I rarely use my scoring blade because they cut a very, very slightly different kerf, it's a minute difference but on many joints it just introduces another opportunity for error to creep in. Zero clearance inserts and a freshly sharpened ATB blade usually give a better finish provided the operator is paying attention.

I think scoring saws have their main advantage in industry, where a foreman can set the saw with a scoring blade and then let a trained monkey load the workpieces all day, that'll give you a 95% optimum cut for minimum cost, but if you're on top of your kit then you can do that bit better without the scoring saw.

 

[Giff]

Thanks Custard. Good points. I am looking at a new blade as well just for the ply. It's too expensive to keep traring it! Groff

 

[blackrodd]

A quick trick that works for me, is to fit a false bed, using a off cut piece, 3mm, or 4mm thick sheet of hardboard, or ply, 2" longer than you're saw bed and, say 6" wide.
Nail or screw a piece of 2" x 1" as a stop and feed on to the running saw, against the fence, until it is against the stop batten.
This will support the cutting area very well and improve breakout, until enough sawdust and debris has made the toothed area larger, just cut a strip off one side and use again.
Works a treat cutting across the grain on ply.
You will no doubt have experienced the good results when first using a new cross cutting sled. and may be aware , when used a lot, the cuts aren't so neat and tidy, after a while.
Regards Rodders

 

[doctor Bob]

I think scoring saws have their main advantage in industry, where a foreman can set the saw with a scoring blade and then let a trained monkey load the workpieces all day, that'll give you a 95% optimum cut for minimum cost, but if you're on top of your kit then you can do that bit better without the scoring saw.

Bit harsh, strange how industrial or commercial woodworking is perceived to be done by thickies, and thought that they only do it to 95%.
and yet we can set our scoring blades up spot on but find no need to belittle the smaller guys who can't

 

[rafezetter]

I saw a youtube with Matthias Wandel where he ran a bit of ply backwards through a low set blade before raising it and running it normally; he said it did the same job as a scoring blade to reduce / remove breakout. I can't remember which of his vids it was though.

 

[RobinBHM]

I find sharpness is the key, with a freshly sharpened rip blade its possible to cut far eastern ply without chipping out. So I would try that first. Blade height can affect break out, its worth experimenting and finding the height that minimizes chipping on both faces.

Pre scoring blades need careful setting up to be worth using. There are various designs of scoring blades, some split, some fixed, some tapered. Some seem to work better than others.

 

[Bod]

The scoring blade is running "backwards"?
IE cutting up, rather than down.

Bod

 

[custard]

I think scoring saws have their main advantage in industry, where a foreman can set the saw with a scoring blade and then let a trained monkey load the workpieces all day, that'll give you a 95% optimum cut for minimum cost, but if you're on top of your kit then you can do that bit better without the scoring saw.

Bit harsh, strange how industrial or commercial woodworking is perceived to be done by thickies, and thought that they only do it to 95%.
and yet we can set our scoring blades up spot on but find no need to belittle the smaller guys who can't

Bob, "trained monkey" was rude and if I've caused offence then I apologise.

The rest of what I said however I stand behind.

Firstly, you're not "industry" in the sense I mean. You don't churn out container loads of KD furniture, you don't order raw materials by the train load, you know employees' names.

Secondly, there's no alternative to driving costs out of a business. And skill costs, so de-skilling, wherever it's achievable within a given quality level, is an inevitable part of commercial survival.

Thirdly, a scoring blade has a kerf that's 0.2 or 0.3mm wider than the main blade. That's why I call it "95%", because it's effectively cutting a micro rebate. It's good enough, but it's not the absolute best. For example if you put a lipping on a score cut board there's a minute gap, it may be on the underside and it may not be all that visible when first applied, but a combination of glue squeeze out and household grime will make it more visible over time. Not one customer in a thousand would likely spot it, but the Guild Mark appraisal committee surely would!

 

[Sgian Dubh]

Thirdly, a scoring blade has a kerf that's 0.2 or 0.3mm wider than the main blade.

custard, doesn't the matching of kerf depend on the combination of the two blades in question? For instance, a main blade could cut a kerf narrower than a fixed width scoring saw, although I think fixed width scoring saw blades are fairly rare. Most scoring saws come in either the split form (two plates) supplied with shims so the kerf can be matched to the main blade, or the conical/ tapered profile where raising or lowering the blade, and sideways adjustment result (for both types of blade) in a matching of the two kerfs. Setting up can be a bit fiddly with both types, and sometimes a perfect match isn't always necessary, e.g., matching just one side of the kerf may be all that's needed for a particular job.

Generally I've found I prefer the split style of scoring saw because once set up it doesn't matter if the board being cut is warped slightly with a concavity facing downwards (or there's a few chips or dust between the table and the board). In this situation the conical/ tapered style of blade's kerf narrows as the concavity passes over it, which is not ideal and more likely to result in chip-out. Slainte.

 

[doctor Bob]

The Industry have pre millers on their edgebanders and now do invisible glue joins , bloody fantasic, mind you for £100,000 plus per edgebander so it should be.

 

[Giff]

Update. I tried Rafezetter's idea of running the board through backwards, like Mathias Wandel did, but this means removing the riving knife or it's a bit tricky.....I then tried a scoring cut going the right way, about 1/2 mm then to the full board depth and got a perfectly clean cut. A bit of a fan but works really well.Thanks for the replies. Geoff