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Just built this Moxon vise. I’m adding the thin spacers with a little block to provide radius to the jaws, covered with foam. Is there a “best practice” for the type of foam to use, or avoid (nitro friendly foam)?

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Measure Twice,

Karl Borum

Karl--

I don't know about whether there are recognized best practices here. Different people like different things. I will share what I like:

1. First, it is good that you recognize that the jaws need a radius; otherwise, the flat, inflexible jaws will bear against the arched top/back and will likely crack one or both when you close the jaws.

2. If you want to use blocks that will bear against the edges instead of against the arched plates, I actually like using 1/8" leather for the faces of blocks like that. Thick leather is great for grabbing guitar parts. But since the leather only gives so much, you have to be very careful closing the jaws.

3. If you want to use foam, I prefer closed cell foam to open cell foam. Open cell foam is very spongy; it is seat cushion foam. Closed cell foam is pretty rigid. To me, the ideal is to cut an arch into large pieces of closed cell foam so that the foam only grabs the edges, not the plates. This is what I do in my own vises of this type. I use leather for smaller things that grab guitar parts (like parrot vise jaws), but closed cell foam for things that grab the whole guitar body.

Good luck!

I like the new-to-me feature of leather being grabby- a hybrid of both may be in order- leather over foam over the thin wooden inner. Thanks for the ideas.

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Measure Twice,

Karl Borum

Karl—

Sounds good! If you do use leather, let me re-emphasize the thickness. Thin leather is not as useful as thick leather. You can buy 1/8” thick leather online. I use the type that comes in 3” wide strips, a few feet long. I cut little patches off that roll. The rough side glues to wood with Titebond, leaving the smooth side to touch the guitar parts. I love it as a caul face material, a vise jaw face material, etc.

I used 1/4” plywood covered with cork. Copied it from Sylvan Wells many years ago. They flex enough so they grab mainly on the rims and have not ever damaged any instruments.

IMG_8987 by Terence Kennedy, on Flickr

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Terence - My setup is essentially identical to yours right down to the pipe clamps.

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We use leather a lot and we get our leather from yard sales to thrift shops where someone is selling an old brief case or even a leather coat if the leather is thick enough.

We used leather for our version of this body vice but it's not yet unpacked so no pic from me of this today anyway.

When I hung up my Coach brief case from corporate America around 20 years ago I sliced it up to make jigs and vice jaws out of it. The "Coach" tag still hangs to this day on my leg vice

I buy leather from our local Tandy Leather store. They have bargain bins and sacks full of pieces perfect for cauls, facings on jaws, etc. Multiple sizes and thicknesses are available. I keep plenty on hand, just in case inspiration hits.

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"Act your age, not your shoe size" - Prince

Among all this talk about vice jaws - does anyone know where I can get replacement urethane jaws for the common green pattern makers vice?


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I was making a bunch of easy forms to check the fit of ribs, and then I watched a video series by a Swedish violin maker, who carves his instruments by sound. I thought that is the ONLY way to do it: if it works. So I wet about to see if it works.
This is a smaller, 390mm viola I drew up from a Storioni in a book on Cremonese instruments I borrowed from the Michigan Violinmakers Association. I have no idea what the arching was like on the original. Besides; this is HD cedar decking, and the back is Mahogany.
I am amazed that the idea actually works.
You can find the arch height, this is about 18mm, and the aching is created by planing down spots that are higher in pitch when you scratch them, or tap them from the back.

I don't have a lot of time in this one, and it isn't nearly done; I haven't reached the groove on the edges yet, but I am excited that it works. The idea should work for archtop guitars too. Maybe even for carving bracing? This arching came out VERY flat across the top all the way to the middle of the bouts. It reminds me of a Montagnana violin that I made a couple copies of, but even flatter, and fuller. The cross arches rise very fast. I wouldn't have made it like that, but that is what the wood wants to be.

Now if the back turns out looking like a back...

https://youtu.be/yQkjngP-XNM?si=uPlm3u05fbdKCfnt

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Why be normal?

Hi Brad,
I don't have a source for urethane jaws (pads?) but one thing I have been using for padding vise jaws is standing mat foam material. A 2X2 ft. standing mat gives a lot of material to pad a number of different vises.

Brad--

StewMac sells them:

https://www.stewmac.com/luthier-tools-a ... ent-parts/

Oh, of course! Thanks, Don.


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Hesh did you build all those electrics?

No I've only built acoustics the electrics are purchases. I collect and play a lot these days.

I do that when carving braces. Tap all over the outside listening for tight spots, and if there is a brace underneath (and there usually is), remove some material from it. But I also flex to feel the stiffness, and use my eyes to judge the big-picture stiffness distribution. And I'm only using it for fine-tuning. That's really cool if you can hear where to remove wood before you've even begun carving

Just about ready to close up a BRW/Lutz Spruce falcate classical

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I have the belly of that viola pretty even now. The method works good. Once you get the basic shape, you can see, and especially feel where the curves are not flowing perfectly. Tap under them, or scratch over them, to confirm. Now I'll work on the mahogany back. Not a fan of the cedar for carving, It looks fairly good with a scraper, but easy to tear. It looks really nice right from a plan, but then you have to plane EVERYTHING.

The arching came out different from anything that I've done. That's what the wood wanted.

Yes. It is 53 degrees out. It was 56-58 in the basement yesterday!

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Why be normal?

Here's a Torres style classical that I started two years ago. Some commissions got in the way, and I'm finally back to it. Lutz top, cedar neck, birds eye maple B&S.

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Ken are your orchids shooting out flower spikes? I have about 4 of my 8 spiking right now and hopefully more to come.

Hesh, the orchids are my wife's. She has 4 there, and 1 in another room. I have a Rattlesnake plant in the living room. It spooked my wife one night. She got up from the couch, and started looking around it. She said she saw it move. It does move. It spreads itself out in the day, and curls up at night!

We got the large orchid at HD last year before Thanksgiving for something like $5. It has flowered continually since then except for a few months when the first flower spike finally gave up: when the second flower spike started. This spike flowered further down, then started taking off, and branching. Now the flowers are opening on the end.

My wife says, "Orchid spray mist. It's almost like cheating." She also waters them in the bathtub. The orchids seem to like the big east window. The rattlesnake plant does fine in the fairly dark living room.

I like planing the mahogany better. The ribbon figure isn't as troublesome as the soft wood. It does have a back shape with a more roundish long arch, instead of the very flat long arch.

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Why be normal?

Very cool Ken I've been growing orchids for about 23 years now and Sunday is my "tend to my orchids" day.

I have a few that have been around for ten years or so and flower every year.

They say that an orchid can live indefinitely with the right care.

An east window is great they don't want direct sunlight but very bright indirect light.

I'll have to google the snake plant that's a new one to me.

Thanks man!

McMaster Carr sells sheets if you're interested.

Couple-a necks.

Yesterday I put stuff away. I was making forms to test the bend of sides. Then I saw the videos on carving violins by scratching and tapping. Then I started making two forms for a couple violas. I got one don't then the bandsaw broke. Then I cut the smaller viola's back and belly out with my large fret saw, and started working on them.
NOTHING got put away.
So it is good now.
Underneath some plans, for the guitar forms was the 16" archtop belly I have roughed out. I scratched it.
It's almost there already.
So a couple hours of scraping, and it is 3/4 done; from the middle out. The idea works for arch tops! I think I was lucky that I kept the arches really smooth and gradual. I carved it from the inside first; with diagonal cross arching, like x braces.
The snake plant spread out in daytime mode. The underside of the leaves is purple.

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Why be normal?