Experiments with chatter.

[Russell Neyman]

For some time now, I have wanted to figure out how to achieve dramatic chatter effects, and received a four-tip RMW "Deluxe Chatter Tool" as a Christmas present. It didn't take me long to grab a piece of maple and crank out some test pieces. My intention here is to show you what worked (and what doesn't) to lessen the learning curve for my fellow woodturners. Here's what the kit looks like:

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A a lot of videos and blogs say that you can get good chatter with spoons, butter knives, and old saw blades held in a pair of vice grips. Meh. I tried that and did not get great results. (I was successful, occasionally, with a long thin bowl gouge extended far over my tool rest.) It should be noted that all of these are on tight-grained maple end grain. Here's what I was able to do with this kit, using different profiles plus a Wagner spiraling tool:

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Both the convex (bead-type) and pointed tips were used. The faster the lathe spins the wood, the coarser the pattern, and if you want finer, more subtle texture, slow it down. The dark area is actually burn from friction.

Here are are several more basic samples using various tips.
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The slowest speed employed here was 450 rpm and fastest 1900. I also experimented with pre-finishing the wood with CA, thinking it might harden the densest grain. That worked, too:

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What I took from all of this is that a purpose-built tool is worth the investment and that there are multiple factors (wood density, speed, pressure, etched) that affect the end result. I'm sure some other "vets" will have other tips, too. I will add to this thread later with more results to my experiments.

[John Keeton]

Russell, those are some interesting effects. I haven't tried chattering, as such, because I was always concerned about being able to predict the outcome. I don't think that is such an issue if one is doing kid's tops, etc., or one off small projects. Most of what I do are finished pieces I already have some work into and I can't get past the paranoia of messing up a piece. So, I opted for the Micro Sorby tool and the Wagner tool. I have been pleased with the results and the predictability.

I don't want to hi-jack your thread, and I only post these pics for whatever interest you may have. These are some demo disks I use in classes I teach. There was no sanding done prior to texturing, as I was just playing around. For a finished piece, I would want a surface sanded to 320, at least.

Most of these disks have some varying profile on the surface, which I think does add to the interest level. The patterns on these were done at around 400 rpm for the inner most pattern, and gradually reducing the speed outward down to around 375. The disks are between 4-6" in diameter. Some of the patterns don't show well in the pics, and I apologize for that. Some have been dyed, some scorched, and some sprayed with flat black lacquer and highlighted with metallic paint.

[Jay Jolliffe]

When you do the chattering is that one pass with the tool or multiple...If it multiple how does it track in the same chatter?

[Russell Neyman]

Good addition, John. I like the concept of varying the speed. I see you used a detail tool (skew, perhaps) to delineate the borders of the chatter.

I was never a big fan of the colored marker technique. Seems to me that SHOULD be relegated to tops for small kids at the county fair.

[Russell Neyman]

When you do the chattering is that one pass with the tool or multiple...If it multiple how does it track in the same chatter?

One pass per patterned area almost exclusively. In the first (left hand) photo of the sample set, I picked up the square tip for each row, angling the tool slightly to give it a stepped effect. Then, I used a tiny detailed to accentuate each section.

[John Keeton]

Russell, I used a three point tool, D-Way Diamond tool and D-Way beading tools to set off the various areas. The diamond tool and three point tool were used interchangeably- whichever was close at hand.

[Peter Blair]

John, hard for me to tell from your photos but are these all end grain? Usually I am reluctant to try this process but some of your results may just change my mind!

[John Keeton]

Peter, they are all face grain. I would think end grain would produce an entirely different result, but I haven't tried it.

[Len Mullin]

John, you should try the chatter tool on end grain, that's mainly what they were made for. I think that you'd be pleased with the end results.
Len

[John Keeton]

I feel like I have hi-jacked Russell's thread and that was not my intention. My apologies.

I do not equate the Sorby and Wagner tools with chattering, as they both function more as embossing tools with some cutting action depending on how they are used. As for end grain use, my application for these tools is nearly always on face grain simply because of the type of work I produce. They may do fine on end grain, but I just don't have much need for that application.

Again, Russell, I apologize! At the moment, I felt you were exploring options for texture, but in hindsight I should have started a new thread.

[Doug Ladendorf]

Russell, thanks for posting your detailed experiments. I have used texturing wheels but not a chatter tool, and have needed a bit more explanation like this. Looks like it would be fun to give a go!

Doug

[Russell Neyman]

Again, Russell, I apologize! At the moment, I felt you were exploring options for texture, but in hindsight I should have started a new thread.

Not at all, John. Those who follow my posts know that I'm all about the exploration of the craft; offering my own experiences and seeking the advice of others. It all adds up to advancing and elevating the craft.

[Russell Neyman]

And another. I really like the more subtle chatter. This is with a square (flat) edge, stepped.

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[Russell Neyman]

From George Vondriska:

1) Low rpm results in finer patterns, high rpm results in bigger patterns.
2) A high-pitched squeal means you’re making a good chatter (be sure to wear your hearing protection).
3) Allowing the cutter to project farther from the tool creates a heavier, more widely spaced pattern. Start with the cutter extended about 1".
4) The tool should angle down slightly toward the work.
5) Cutting on center makes a pattern with lines that radiate straight out from center.
6) Cutting below center makes lines that spiral clockwise, while cutting above center makes lines that spiral counterclockwise.
7) Leaving some spots unchattered creates a visible contrast, which will highlight the textured work.

[Russell Neyman]

Two more using a friend's lathe that has a reversing feature. Mine doesn't. I'll also say that hard, DENSE end grain makes all the difference in the world. In the early test pieces, I used maple that wasn't very hard, and got so-so results. This piece of lignum vitae really shows better.

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[Russell Neyman]

I've been experimenting with various species of wood and the results vary remarkably from tree to tree. The best results have come from cocobolo, lignum vitae, Blackwood/ebony, and some old growth teak.

One ne more thing I've learned it that raising a burr (the old cabinet scraper technique) really helps!

[Russell Neyman]

An update: As noted earlier, the target wood needs to be dense end grain. Yesterday I added a pattern to two pieces, mahogany and plum, neither of which are particularly dense. What I did in this case was burnish the wood with the side of my oval skew, pressing firmly at moderately high speed. That did, indeed, harden the wood and created a sheen on the high spots, enhancing the effect.

Here's the plum:

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and the mahogany (a bottle stopper) which had even better results:
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It it should be noted that there is no finish or polish on either of these. The sheen is all due to the burnishing. I chose the oval skew because it distributes the pressure more than a gouge shank (which I sometimes use to burnish) but almost any piece of smooth steel will work. I also use this process when I'm beading and need that wood to be harder.

[Reed Gray]

It is interesting to see the chatter lines that are more square to the rim of the lid rather than the swirl type. Does that come more from a square tip rather than point? Looks like some are lines where you just hold it in place with no sweep. I have always had trouble getting the swirl to be a smooth arc rather than a kinky swirl. I have tried a smooth even draw, and that doesn't seem to work. I have wondered if starting to sweep from center to rim works better if you start slow and speed up, or start fast and then slow down. Smooth even sweep just doesn't seem to cut it...

robo hippy

[Russell Neyman]

Reed: Not to make too much of this, but the "sweep technique" (applying the tool in the middle and pulling it to the rim) rarely gives me much more than I can get with a spiraling tool, which I also use. Dave Schweitzer and I spent an hour or two tinkering with techniques and concluded that a series of bands was more "refined" so I've gone with that. But there's a significant difference sweeping from the center straight across (3 o'clock position) to sweeping down (5 o'clock).

On on the mahogany bottle stopper pattern, i oriented the outer ring at one angle at a fairly high speed using a bullnose-shaped tool with a fresh burr, then reduced speed and did the next pass at the opposite angle, rotating the tool counter-clockwise. This is one of those things that's hard to put into a written description; perhaps I should drive down and we could shoot a YouTube video to show people in more detail.

For those who are following this and doing their own bit of experimentation, I strongly urge a trial-and-error test before the final pass. Every piece of wood behaves differently.

[Russell Neyman]

Had an open shop today, and we messed some more with the chatter tool, doing 20-30 test pieces. Here's the last one off the lathe, spit polished to a gleam. This is madrone.
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[Bob Bergstrom]

You guys are inspirational. I may have to break out the texturing tool and follow it with the blow toarch. Looks lik a interesting surface to burn?