Scratch Stock Advice

Hi All,

I am just after some advice about using scratch stocks. I want to create a small bead on a curved apron for a side table i am making. I mad the scratch stock out of an old saw and flattened it on a stone.

It works great going along the grain, but as the wood has some curves in it, it "catches" and gest stuck and tears when it crosses the grain.

I an having trouble with this. I have ended up using the scratch stock freehand, as it seems to work better than when i had it held in a some wood with a fence. I have tried tilting the blade and going very lightly to build up, but doesn't seem to make much difference.

In the end i have resorted to using a chisel to sever the wood fibres where ever it catches on the grain. This helps but still not great.

Any ideas?

Attachment 344293Attachment 344294Attachment 344295

Thanks in Advanced

This is a common problem with scratch beading I'm afraid, marphlix. What I do is reverse the direction of travel as soon as one of these catchy bits starts to develop. By holding the stock hard against the reference edge and taking light cuts with the blade leaning into the cut a bit, you can usually remove the nubbins that is causing the cutter to catch. But sometimes it won't smooth out easily, and a little bit of judicious paring may be needed. Although it's a very simple tool, the scratch-stock has a few little quirks like this, but with a bit of practice, you'll learn to read the signs and reverse cutting direction before the catches get too big to clear easily. I also find it helps if you only work short sections of the bead at once, particularly on curves.

Cheers,

Thanks Ian,

I still have 2 more aprons to go, so ill try that. I might put it back in the fence and raise it up so that it will force it to take a very shallow scratch and then progressively lower it. I imagine that will be a slow way of doing it, but if the results are better - i'm happy.

Cheers

Quote:

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Originally Posted by marphlix

.... I might put it back in the fence and raise it up so that it will force it to take a very shallow scratch and then progressively lower it. I imagine that will be a slow way of doing it, but if the results are better - i'm happy...

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You should certainly try setting the cutter at different heights, marphlix, it may do the trick for you, but I find when making small beads, I need plenty of exposure of the cutter or it jams with shavings very quickly & stops cutting. If I set it so that the top arm acts as a 'depth-stop', the shavings/sawdust compact between the top arm & the cutter and after a few strokes, I get no 'bite' at all, until I clear these. If I drop the cutter down so the cutting edge is well below the top arm, that doesn't happen, because the shavings can easily fall out of the way. Not having a set depth stop doesn't matter because you can clearly see how your bead is progressing, and move on as soon as it looks nice & rounded. Once the whole bead is pretty well formed, a few full-length strokes will usually even it all out very nicely.

You will probably have this all figured out for yourself by the time you've finished this job... :U

Cheers,

Ian has give good advice. One point I would add is, when scratching beads, slightly chamfer the outer edge with a block plane so that there is less wood to remove. That is also where reversing grain can tear off. The less wood one removes at a time, the less likely any tear out.

Regards from Perth

Derek

OK, i finished all the scratching on the weekend. I found another way of doing it. I'm pretty sure its not conventional - and i'm not sure what implications it could have, but it worked quite well for me.

I ended up taping (hammering) the scratch stock into the edge of the board to create lots of tiny cuts, i was then able to lightly run the scratch stock over this and progressively remove the wood and create the bead. It wasn't that slow in the end and i got less tear out too. i need to go over the whole lot with sandpaper - but i'm happier with this result than all the previous attempts.

Attachment 344660Attachment 344661Attachment 344662

Cheers guys

Quote:

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Originally Posted by marphlix

....I ended up taping (hammering) the scratch stock into the edge of the board to create lots of tiny cuts, i was then able to lightly run the scratch stock over this and progressively remove the wood and create the bead....

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Well, certainly not conventional, marphlix, but what works, works. So far, I've managed to get scratch beaders to work the 'conventional' way, but I'll keep your method in mind, in case I ever strike a really recalcitrant wood. :U

Cheers,

It has just dawned on me that you scraped/scratched the molding freehand. I would not have done this. The risk is that the cutter follows the grain. A fenced beader enables you to control the cut. What is needed for a curved profile is a fence that runs along the curve. Did you not try doing this?

I am pleased that you were successful in the end. As Ian noted, your unorthodox approach worked well enough. You certainly tapped the blade deeper than I would have, since this increased the risk of breaking off chunks (following the grain).

Regards from Perth

Derek

:doh:
I hadn't figured that out, Derek, but now you've mentioned it, none of the pics actually shows a stock - just the cutter!

Marphlix, p'raps my posts will make more sense if I point out this is the sort of scratch stock I thought you were talking about:Attachment 344680

These are about as simple as it gets, there is a slot in one arm of the "L" for the cutter, which is clamped in place by one or two bolts. The other arm acts as the fence.

Actually, there is a simpler tool, that cuts a quirk & a half-bead - a slotted steel screw driven into a piece of wood & shaped a bit with a round file: Attachment 344681
Does a surprisingly good job on straight runs - you can finish the outside of the bead with a block plane.. :U

I've got a small drawer full of scratch stocks made for various jobs, including a knock-off of the one LV had a few years back. It works no better than the simpler kind, but does give you a bit more to hold onto: Attachment 344682

Cheers,

To follow an inside curve, the Stanley #66 beader is one of the first tools I would consider. It comes with a curved, single point fence, which is the only way a beader will follow an inside curve. Outside curves are easier and may be scratched with any of the beaders that Ian shows.

Here is the Lie-Nielsen version ...

http://www.inthewoodshop.com/ShopMad..._m78f24149.jpg

Regards from Perth

Derek

Quote:

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Originally Posted by derekcohen

To follow an inside curve, the Stanley #66 beader is one of the first tools I would consider. It comes with a curved, single point fence, which is the only way a beader will follow an inside curve. Outside curves are easier and may be scratched with any of the beaders that Ian shows.....

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:?
Derek, any of the scratch stocks in the pic above will follow either inside or outside curves (except the 'screw in a block' which is really only effective for straight runs). By rounding or chamfering the edge of the 'fence' arm. you can follow a pretty tight radius, certainly tighter than anything I've ever wished to put a bead on. In fact, I would say that in general, 'inside' curves are easier than outside, by a small margin.

It takes a little bit of practice to become proficient with these things, but most people should manage a pretty convincing profile on the first or second try. I don't know if the 66 style beading tool is any better than home-made scratchers, I've never had one in my hands to try. If I ever stumble on one at a price I'm prepared to pay (i.e., next to nothing! :;) I shall certainly bring it home & give it a workout, but in the meantime, scraps of wood and saw blade offcuts have always done a pretty good job for me. And the price is right.... :U

Cheers,

Thanks guys,

I did initially try the cutter in a piece of stock, but i found i couldn't control it well. It was probably my technique - as i didn't try it for very long. I will give it a go again using a stock piece and hopefully it will do better.

I really appreciate the input and advise!!

Thanks, Dave

Quote:

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Derek, any of the scratch stocks in the pic above will follow either inside or outside curves (except the 'screw in a block' which is really only effective for straight runs). By rounding or chamfering the edge of the 'fence' arm. you can follow a pretty tight radius

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Hi Ian

It is difficult to see how wide the fences are. If they are straight and wide, they will not ride close to the side of the board (Edit: I wonder if that's what happened when Dave tried a holder?). The narrower the fence, the closer it will ride on a tight inside curve. A tight radius on a flat fence - as you note - gets there.

Regards from Perth

Derek

Quote:

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Originally Posted by derekcohen

.....It is difficult to see how wide the fences are...

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Derek, many of the scratch stocks I make come out of a scrap of what I happen to be working on, & the most common thickness would be ~3/4", that being a pretty standard dimension for cabinet material. :U So all they need is a small chamfer to follow an inside curve of quite tight radius. These are extremely simple tools, made on the go to do specific jobs, so dimensions vary, but the width of the fence bit is pretty much immaterial, so long as it is wide enough to hold onto, and not so wide as to be downright clumsy. Ditto for the arm....

Cheers,