Gooseneck tool holder

partsproduction · Sep 8, 2016

Most of you have doubtless seen and many have used these. I bought one for one of my shapers recently, but the way it works seems self defeating.
It is an Armstrong S-51 holder like this one;

What I am not sure of is the function of the screw jack at the bottom. Is it for roughing, and before finishing is screwed back to allow spring? Or is it supposed to always be pressing against the back of the goosneck?
Thanks,
parts

Salem Straub · Sep 8, 2016

It's for pushing that disgusting Miller Lite farther away from your tool post, at all times...

Sorry about that, don't have an answer for your actual question.

Robert Lang · Sep 8, 2016

It's a threading tool holder for the lathe.

Rob

partsproduction · Sep 8, 2016

Miller Lite

I pulled the photo off the web, didn't even know it was beer!

I do have a radical reaction to alcohol, the smell of beer or other stuff is gut wrenching for me.

Robert Lang, you are right, see it in the catalog; http://pounceatron.dreamhosters.com/docs/misc/Armstrong-Catalog-THB49-1947.pdf

But what is the purpose for the little jacking screw? It takes a standard square 5/16" HSS tool, so it will work fine in the shaper for facing.

I do see the anti-chatter abilities, but not when the jack screw is tightened.

Atomkinder · Sep 8, 2016

partsproduction said:
I pulled the photo off the web, didn't even know it was beer!

It's not!

enginebill · Sep 8, 2016

I do believe that the screw is for roughing but that is just an educated guess.

Limy Sami · Sep 9, 2016

Sorry to rain on your parade parts, but tool holders with the cutting edge higher than the shank seat are not good shaper tools as they have tendency to dig in ..oddly enough especially when finishing

This shows what I mean, Stephen Thomas's post #14 shows it best http://www.practicalmachinist.com/v...holder-shaper-sharpened-roughing-tool-311838/

enginebill · Sep 9, 2016

The spring tool works the same way as the tools in Stephen's post.

stephen thomas · Sep 9, 2016

OP's tool is not actually for a shaper, but you can try it and see how it works.

My understanding of how to use that for threading on a lathe was to set the jack for roughing to hold dimension and roundness. Then loosen it and take a few tenths spring cut for smoothness, if there was chatter.

smt

partsproduction · Sep 9, 2016

Thanks all, I can see that probably the S-51 gooseneck, being less resistant to the forces of the cut, should move up and back in the cut in response to excess force, it should do so before any other part of the holder or clapper box.

Whether or not it will not chatter remains to be seen. This tool holder is too big for any but the Alfred Eriksen or the Havir Shape-Rite shapers.

Mike C. · Sep 10, 2016

A true gooseneck shaper or planer tool, as shown in my old books, is not the same as this. A gooseneck actually hangs behind the plane of the shank and ends up at the axis of the clapperbox hinge. That is the trick to eliminating chatter.

partsproduction · Sep 10, 2016

According to Armstrong the tool holder I have, same as the one in the photo with the beer can, is what they call a gooseneck tool. I understand the difference between this and the one's you guys are thinking of, however, the setup will give at the weakest point, or that joint that has play in it. The weakest point of the S-51 tool in a shaper clapper is that gooseneck. It is the point, or better phased area, where the flexing will give the actual tool an upward/backward movement. The sectional area in the gooseneck is about 1/3 that of the shank.
This area is "above" the actual cutting area, so the only doubt I have is whether or not shaping forces are enough higher to overwhelm the gooseneck. Still, even with the jacking point tight the flexing will still be ahead and above the cutting point, so even then it should provide some anti-chatter benefit.
I suppose if it doesn't I can sell it on ebay to someone who still uses compound destroying lighthouse tool posts.

Andy FitzGibbon · Sep 10, 2016

As Mike says, the whole point of a gooseneck style shaper tool is that it brings the cutting edge in plane with the clapper. Nothing to do with flex.

Personally, I wouldn't want to introduce any tool holder flex into shaper operations. But, a lathe threading gooseneck might work just fine. It's worth the experiment.

Andy

mach2 · Sep 10, 2016

I've no experience with a goose neck tool holder but have always reasoned the shape, as already stated was to allow the tool to deflect away from the work and the screw was to limit that deflection.

partsproduction · Sep 11, 2016

The "True" gooseneck approved here for shapers gets it's chatter resistance from flexing up and back from the cut. Somewhere it is flexing, and most of us understand that the "give" is coming from someplace. The approved shaper/planer gooseneck is very rigid so the flex has to be in the pivot pin and other slop within the clapper box for it to work at all, therefor all of it's tool movement up and back is due to it's geometry relative to the clapper.

The Armstrong Gooseneck S-51 just makes the place of movement where the engineers wanted it, a short distance ahead and above the tool itself.

Many of us recognize that the common shaper tool, (the top two are gooseneck tools for threading apparently according to the Armstrong catalog) at the bottom of the above photo is very commonly used in shapers. The tool for best practice should trail the holder, not lead it.

By the way, I swiped that photo from Kay Fisher's Shaper page, http://www.neme-s.org/shapers/columns/shaper_column_42.html

And he says this; "The two tool holders in the top of the picture have a small dimple and ram nut that sets them up as a left, right, or straight holder. They are actually lathe threading tools but work well as shaper tools. Unfortunately, they have no built in rake and have the cutting bit further forward than I like. "

So my thinking on the gooseneck for shaping isn't mine alone. But we'll see when I get the shaper done how effective this S-51 is.

Andy FitzGibbon · Sep 11, 2016

Your assessment of how the S-51 tool works is correct, but Armstrong's shaper tools do not work on the same principle. They seek to eliminate chatter by MINIMIZING flex and spring, not by introducing it. This is accomplished by moving the tool's cutting edge closer to (or, in some cases, behind) the center line of the clapper box.

Period treatises on shaping and planing, along with Armstrong's patents, bear this out. By the way, your original question is answered in the patent for the S-51: the jacking screw is simply to de-activate the spring feature when it is not wanted, to make the tool holder more versatile.

Andy

stephen thomas · Sep 11, 2016

partsproduction that bottom tool in you photo is interesting. I've seen very few (if any?) tools specifically designed for a shaper/planer with built in rake, but with the tool well behind, it should work. Would save a lot of tool end grinding. Now I've got to put one of those on my to-do list. :rolleyes5:

smt

Mike C. · Sep 16, 2016

It's not the give that reduces chatter, it is geometry. If you imagine the clapperbox swinging through an arc, with a usual straight shank Armstrong or similar holder in the toolpost, the position of the cutter above the face of the clapperbox means that as it loads up, it digs in deeper. It's like having your lathe tool above center. The true gooseneck for a planer or shaper puts the cutting edge at the axis of the clapperbox pivot (or at least a lot closer to it), so that the tool doesn't dig in under load. If it loads up heavily, it actually flexes out of the cut, rather than deeper.

partsproduction · Sep 16, 2016

I respectfully disagree Mike.

It may not be visible movement but without movement it doesn't matter either way.

The only reason to have the cutting edge behind the pin of the clapper is so it can give (Microscopically perhaps) out of the cut. If the tip of the tool is in front of the pin it can move down deeper, because of give. The gooseneck does exactly the same thing as having the tool behind the clapper pin, all movement is up and away from the cut instead of deeper into it.

Without movement none of it makes any sense, nor any difference at all.

In fact, for exactly this same reason cutting tool back rack is critical with a poke tool, there is no way to have that tool bit behind the clapper pin. But if the face geometry is right the tool will try to go up and out instead of digging deeper. Too little face hook and it won't cut at all, too much and it digs in.

I have the gooseneck tool in the shaper now. I'll try it tonight or this week end. But with the gooseneck even with a little too much face hook the tool should spring back out of the cut instead of digging in, which is also what having the tool face behind the clapper pin accomplishes.
If it chatters I'll let you know.

partsproduction · Sep 20, 2016

Feed back on that gooseneck tool in my shaper, It didn't seem to work, far too springy with the little jacking point out, and no advantage with it in over a solid holder.

Just for the record.

Gooseneck tool holder

Titanium

Cast Iron

Stainless

Titanium

Titanium

Stainless

Diamond

Stainless

Diamond

Titanium

Diamond

Titanium

Diamond

Stainless

Titanium

Diamond

Diamond

Diamond

Titanium

Titanium

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