tilt-a-whirl positioning fixture

[Bob Hammond]

Hello, here's something that might be useful, and I could use advice about. I wish I could have an Emmert patternmaker's vise, but that's a bit beyond my means and needs.

(I'm sorry, you'll need to tilt your head to the left; I can't get the pics to cooperate clockwise.)

I'm getting to an age where I like to position a workpiece so that is comfortable to work, for my eyes, hands, neck, and spine (It's Hell getting older!) So I made this Plumbers' Special positioning fixture from ~$25 of 1/2" pipe fittings and some scraps. It allows me to position a workpiece at a comfortable height and attitude. There are two floor flanges, two unions, and a few nipples. The captured service wrenches are made of baltic birch. I haven't decided how and where I will permanently mount this fixture, and so for now it's just screwed and clamped to the corner of my bench. Also, I suppose 3/4" or 1" pipe & fittings might be heftier, but I'm not chopping wood here

As for my question, it occurs to me that it would not be difficult to install a vacuum clamp system. Somewhere I could install a Tee with a hose-barb fitting for a vacuum line, and then rout a groove around the plantilla/plate for a vacuum gasket. My question is, would that be secure enough so that an instrument would not slip, or catastrophically, fall off?

[Jason Rodgers]

This is cool, Bob! I like the captured wrenches... I never would have though of that.

And yes, a vacuum clamping platen should be able to hold a guitar securely at any angle. I made a very crude vacuum hold-down for carving solidbodies, and I could chisel and plane and torque it roughly, and that's just using weather stripping. This guy is doing what you're talking about http://blog.customguitars.com/scotts_gu ... xture.html

One word of caution: depending on the back wood you're using, vacuum sucks right through porous woods and will not get a good grip. It's easy to test: put your guitar on the fixture, turn on the vacuum, and give it a jiggle. A splash of shellac, which you might have on there anyways at that point, will seal it up.

[Greg Steil]

That is so cool, I love home made tools etc.

[Gordon Bellerose]

You and I must be close in age Bob. I also spend some time thinking about ways to make the work easier.
That is a cool little vise. Allows you to position your work pretty much any way you want it.

[David Robinson]

I love vaccum clamping, but you have to use a reservoir system pump, that constant running pump will drive you mental.


I am making one of these to clamp/bolt on my stewmac stand.
http://www.jerryhartzell.com/wood-carvi ... ving-vise/


I have seen other made from 2" trailer hitch balls.

[Bob Hammond]

David, I like the Jerry Hartzell design, maybe better than what I've done. The height is adjustable, which could be a very useful feature. I suppose that the eyebolt is is strong enough (it certainly is if it's forged).

About using a 2" hitch ball, I wonder if that is too small and too slippery. I remember a carver's station that I saw in FWW several decades ago. It was a bowling ball that was fitted into a clamping leg system (3 or 4 legs?), and the ball had been drilled and tapped to fit a nipple or bolt so as to mount a platform to it or a workpiece. Maybe a bocce or croquet ball might be a more convenient size.

[Bob Hammond]

I guess this is what is known as "going large":

http://www.monsterballvise.com/floormodels.htm

[David Robinson]

Bob - I can see it is a real rabbit hole once you go bowling ball size, with all the hydraulics involved.

As to the eye-bolt - most weld up the return on the eye end. - I liked the idea of having multiple holder types that fit into the eye-bolt part. One with a plate, a threaded end, a clamp, etc.

[Peter Wilcox]

Interesting. I have used bowling balls before.

I still have one rolling around out in the shop getting in the way, and a couple of hydraulic jacks I've never used. Now I've got an idea for them. Thanks.

[Jason Rodgers]

Interesting. I have used bowling balls before.

telescope-bowling-ball-1.jpg

telescope-bowling-ball-2.jpg

I still have one rolling around out in the shop getting in the way, and a couple of hydraulic jacks I've never used. Now I've got an idea for them. Thanks.

That's cool! How does that work?!

[Peter Wilcox]

One ball is the bearing that sits on a rubber pipe coupling mounted on top of a post. The other ball is a counter weight to balance the weight of the telescope so it will stay in whatever position it is moved to.

[David Robinson]

I love the ball counter weight!

[Bob Hammond]

Peter, is that a shopbuilt telescope? The bowling balls give it a planetarium look. Are you scanning into Area 51?

[Peter Wilcox]

Bob, I built that scope probably 15-20 years ago - I can't really remember. The objective is a surplus Kodak aerial camera lens, 36" f/8. I removed the iris diaphragm and shutter. The eyepiece is a huge surplus Erfle about 2" diameter and 1.5" focal length, giving the scope 24 power with probably a 2.5 degree field of view. The tube is some kind of plastic storage container. The telescope weighs a ton, but it's great for nebulae and comets.
Unfortunately I had to take the mounting post down a couple of years ago as my wife wanted a deck there, and since the post was made of alder, I took it apart to make guitar bodies. I have some 8" to 12" diameter creosoted fence posts and telephone poles laying around, so I should make a new mount from one of those, but that entails digging a hole in rocky ground - maybe some day.

[Jason Rodgers]

One ball is the bearing that sits on a rubber pipe coupling mounted on top of a post. The other ball is a counter weight to balance the weight of the telescope so it will stay in whatever position it is moved to.

It just sits there? There's nothing holding it on cept gravity?

[Peter Wilcox]

It just sits there? There's nothing holding it on cept gravity?

Yup. It just lifts off so you can take it in the house when not in use.

[Greg Martin]

Lmi has a vac clamp system and stewmac has the floor stand.both are great if you have a dedicated place in the shop and can afford the 500.00 Plus costs. I like Bobs design although Id hate the captured clamps,they just call to me to get hung up in them ---some how. I carved my archtop using Benedettos carving cradle but by the end I wish I could have been seated. Id like to use something like Michael Lewis's carving cradle which does allow you to be seated.

[Bob Hammond]

The captured wrenches can be disengaged from the unions, and can hang loose or be repositioned so that they are out of the way. They're like the wrenches on a bench vise or older benchtop circular saws from the 40s-50s.