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Robert McGowen
04-18-2007, 8:14 PM
I incorporated several ideas into a press that I built this afternoon that I intend on using for making segmented turnings.

The press had to be:

1. easily adjustable from a couple of inches to over 2 feet.
2. easy to use as far as tightening and releasing the pieces.
3. able to be moved so that I could see all sides of the piece that I was making.
4. cheap!

I used some 11-layer plywood that was in the cutoff bin at the borg. The rods are 5/8" by 3' and were $2 each. The nuts and washers were $8 total. (I have a wholesale account at a metal place) The jack was $19.90 at the borg, but heh, I can always change my tire with it also. So I have about $40 in it total, including the jack.

I drilled 5/8" holes in the top and bottom. I drilled 7/8" holes in the middle so that it would slide easily. The top of the jack meets with the bottom of the bolt and the middle kinds of floats since the holes are larger than the rod. This should take out any errors between the alignment of the top and middle that are doing the actual pressing as they will be able to make themselves parallel to each other.

The bolt though the moveable middle can be unscrewed by hand. I can just unscrew it if I need a flat surface. It is a 1"x 8 TPI bolt and my faceplate screws directly to it. That way I can use a glue block and turn or sand the piece on the lathe and then just screw it back onto the press for the next ring to be mounted. The top is adjustable to that you can lower it down for small pieces or go all the way to 2' tall. The jack also has a lot of travel to it, so you don't have to adjust much at all.

I hope it works as well as I want it to. Thanks for looking and any way you see to improve it is welcomed!

Bernie Weishapl
04-18-2007, 9:32 PM
Robert that looks like it should work well. I will be interested in a progress report and pictures as you glue layers. Thanks for sharing.

Dominic Greco
04-18-2007, 9:59 PM
Robert,
I like your design! Using a hydraulic jack as a "clamp. Neato! Now THAT is a real he-man bowl press!

I assume that you made the "top" double thick to reduce it bending? That hydraulic jack can really put out some force if you're not careful!

If you want to REALLY beef it up, add a cross bar. Just get a piece of 4/4 oak (or any hardwood) about 1-1/2 to 2" wide and as long as the top is wide. Lay it so that the 4/4 side is on the top of the "top". Screw in from the bottom. You've just made a "T Section" beam. And they REALLY resist deflection under load!

joe greiner
04-19-2007, 8:17 AM
Superb. Especially inclusion of the face plate. The smaller middle plate is just to get thread exposure, right? I made a similar apparatus many years ago for a book press, but without the jack; used only the threaded rods with wing nuts. I found it advisable to stiffen the plates (extra thickness), as Dominic points out. A single diagonal above the upper plate would be best; two half-lapped diagonals would sort of defeat the purpose.

Joe

Frank Kobilsek
04-19-2007, 10:18 AM
Robert
Wow, now that's a press.

This is what I do for a living. Design and build spreaders and presses for industrial laminating. (I get alot of adhesive for free) One caution on your press. There comes a point where you can squeeze a joint too much, effectively forcing the adhesive completely from the joint creating a very weak bond or no bond at all. Granted I play with 100 tons of force or higher but my surface area might be 7200 square inches.

Frank

Keith Burns
04-19-2007, 10:50 AM
Great press Robert. I tried building one years ago and my biggest problem was centering the rings. What I ended up doing was turning a centering cone mounted to my tailstock and glue the rings on while mounted on the lathe. I finally ended up buying an aluminum centering cone from Curt Thiebold.

joe greiner
04-19-2007, 12:09 PM
Since there are intermediate posts, I'll add here instead of editing: Strengthening of the top plate should be duplicated on the plate under the jack. Disappointed that I forgot this.:o

Joe

Bill Wyko
04-19-2007, 12:34 PM
Well Robert...It's official. YOU"RE HOOKED!. Segmenting is addictive isn't it?:D Nice press you made there too. Becareful not to squeeze out too much glue or it will make for a weak joint. Here's a pic of my home made press. I use a spacer block to adjust for height.

Don Orr
04-19-2007, 12:58 PM
Man that is some press-great job. So when are you going to make the first 2 ft piece:eek: :D ;) ?

Bill Wyko
04-19-2007, 2:56 PM
Man that is some press-great job. So when are you going to make the first 2 ft piece:eek: :D ;) ?
I'm about 1/2 way through with mine how about you?:D