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mike
11-01-2000, 11:04 AM
I am just starting to set up a home shop and I'm on a low budget.

I would like to make some raised panel doors and I'm wondering if I could use just 2 parallel clamps for the assembly.

Will these parallel jaws square up any MINOR imperfection in the squareness of the styles and rails?

I know that you can never have enough clamps, but what would be the minimum amount (and type) I would need to start a shop.

Thanks
Mike

Bob
11-01-2000, 06:31 PM
Mike-

Bessey clamps(IMHO),are the best choice in clamps.

2 clamps would work, but it's not recommended. Your not applying enough even pressure through the piece. I typically place 2 Bessey K-body clamps running with the rails and 2 to 3, depending on size, parallel to the stiles.

The way to check for squareness, and you may know this, is to measure diagonally from one corner to another. The distance should be the same for both measurements. Any difference can be corrected in clamping pressure. As long as your imperfection IS minor.

You're right, you can never have enough clamps. I try to carefully evaluate the size of the next 4-5 projects I'm going to begin and buy accordingly, if needed; I always buy 2 of each. Add to your inventory as the project demands.

To start, I would get two 12", 24" and 36" bar or parallel clamps. You may choose to make your own with pipe and fittings or go the expensive (Bessey K-body) route. Get a couple of hand-screws, some Bessey mini-clamps and some spring clamps in various sizes. For clamps 50" or longer, I recommend making your own with 3/4" black or galvanized pipe and Pony fixtures; it's much cheaper and they're strong. If they warp/bend, just buy new pipe.

I hope this helps. Good luck.

-Bob

Mike
11-03-2000, 10:50 AM
Thanks for the imput. What I should have said is whether the paralles clamps would prevent the doors from bowing. Sometimes it's hard to get a flat piece to stay flat. Especially without a jointer to perfectly square the edges the bar clamps tend to warp or bow the piece. I'm wondering if the Bessey parallel clamps would help to prevent a piece from bowing. If they wouldn't, I would just buy the Pony bar clamps.

Thanks
Mike

Bob
11-03-2000, 11:42 AM
Mike-

Clamps will bow your piece if your material is too thin relative to the pressure of the clamps, or your piece is significantly out of square. In the later case, your panel won't fit properly, so it doesn't matter what type of clamp you use. No clamp will compensate for error in workmanship. Don't get frustrated; I've trashed plenty of work because of this.

Note: Bowing/warping is typically caused by an increase/decrease in the moisture content of the wood used. DO NOT glue the raised panel to the rails and stiles; just let it float.

In regards to having a jointer, it would certainly be a plus. For now, a high quality hand plane will help more than you think, smoothing out those imperfections.

Remember, you're working on a difficult piece to craft, with limited tooling. Nothing is more frustrating.

I hope this has helped. If not, let me know.

-Bob

Ken
11-04-2000, 05:40 PM
Mike:

Bob has given you some really good advice relative to clamping. I might however, add one or two suggestions. Do not over tighten your clamps. Only tighten unill you get a LITTLE squeeze out along the joints.
You mentioned that you don't have a jointer. Bob suggested hand planning the edges. Ok, fine. Personally, I'd use a router with edge trim bit with bearing and a good factory edge from a sheet of plywood. The result being, for all practical purposes, the same as a jointer. The point being, don't try to pull edges together. They should be almost invisible when you lay your pieces side by side in dry assembly.