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paul cottingham
03-04-2011, 10:19 PM
I realize this may be kind of a tough question, but I am looking for opinions of bowclamps. I made my own cauls, and they work ok, but am wondering if bowclamps might be better. If the claims are true, it would be nice to be able to eliminate a ton of clamps in my glue ups!

thanks again,

William Nimmo
03-04-2011, 10:34 PM
I purchased these a few years ago, and when I use them they are great.

Mike Henderson
03-04-2011, 10:48 PM
There's nothing magic about Bowclamps compared to cauls you make yourself. Why are you not satisfied with the cauls you made?

Mike

paul cottingham
03-04-2011, 11:34 PM
I find setting clamps on my homemade ones challenging at times. I made them from softwood as well. so they don't give me as much pressure as I would like. Not intractable problems to be sure.

Mike Henderson
03-04-2011, 11:41 PM
I find setting clamps on my homemade ones challenging at times. I made them from softwood as well. so they don't give me as much pressure as I would like. Not intractable problems to be sure.

Buy a set of Bowclamps and see if you find them worth the price. Different people will probably have different answers but your opinion is the only one that counts for your use.

Mike

[added note: Increase the amount of curve on your homemade ones to get more pressure in the center.]

paul cottingham
03-05-2011, 12:16 AM
Heh, an obvious solution to be sure. Just trying to avoid having to post them in the next "tools I regret buying" thread.:-)

Julian Tracy
03-05-2011, 12:27 AM
Yea, that could be the useless reply to ANY question asking for opinions about ANY product. I guess he's right, no point in asking - just buy them, what the heck...

JT

Tim Sproul
03-05-2011, 1:58 AM
I have them and aren't exactly impressed with them. For smaller glue ups or glues that can be done flat on a table, they work out better than freestanding use. Trying to get the things started on a larger glue up is a pain with just myself. And then when it comes to unclamp, watch out. The opposing side will spring loose with a pretty darn big bang. This sometimes sends the clamp off and careening and sometimes damaging the work.

I'm not a fan except in certain situations.

Mike Cutler
03-05-2011, 8:10 AM
I have a few pairs of them, 36" and 48". They work just fine, and do exactly what Craig say they do. I haven't had the problem that Tim has, with the clamp releasing tension, though. I position the clamps, stick a clamp in the middle if possible to just hold the clamps in place, Place a clamp on both ends and apply pressure equally at both ends.

If you ever do a large panel glueup, ie. an 84"x40" x2" table top, you won't regret the purchase at all. Even if you use them for nothing more than maintaining the top flat.

Doug Shepard
03-05-2011, 8:18 AM
I've got pretty much all parallel jaw clamps and very few F type clamps so the slot milled into the Bowclamps for the clamp screw head is pretty useless for me, but otherwise I've found them pretty darn useful. They work as advertised and I dont think the price is out of line.

Kent A Bathurst
03-05-2011, 8:56 AM
I find setting clamps on my homemade ones challenging at times. I made them from softwood as well. so they don't give me as much pressure as I would like. Not intractable problems to be sure.


Made mine with 8/4 HM - x-section OD is ~2" x 2". Was concerned at the time that I was over-driving my headlights, but 12 years down the road, I've completely forgotten the $$$ for rough stock, but see the performance results every time I use them.

For "mission-critical" glue-ups, I'll do one joint at a time, with the center of the caul directly over the joint. Worst-case is a scraper plane or card scraper to clean up the joint - bascially comes out dead-nuts level. Coming up: I intend to cut a kerf - maybe 1/4" wide x 1/4" deep - across the center, and position the kerfs over the joint to allow for squeeze-out. Since I use a lot of QSWO, I can't use a wet rag on squeeze-out - just smears it into the deep open-grain pores. I let it get rubbery after ~ one hour, then lift it with an old beater card scraper or chisel.

I made some simple stands out of plywood. The lower caul sits in them, and is elevated a couple inches above the table surface. Boards on top of those, then the upper caul. This gives me clearance needed for C-clamps at the ends of the cauls - stable, predictable, easy to get the clamps on the cauls. Also, plenty of room between the stands/cauls for the "under" pipe clamps [half the "over-under" alternating clamping scheme.

Having said all that, I'd reckon the bowclamps do a fine job. I'd just as soon make my own, but that's just me.

Jim Becker
03-06-2011, 2:35 PM
I have several pairs of the Bowclamps and find them to work as advertised and of very high quality. The radius is milled with precision and that would be hard to duplicate as a DIY project.

Paul Johnstone
03-07-2011, 12:04 PM
I find setting clamps on my homemade ones challenging at times. I made them from softwood as well. so they don't give me as much pressure as I would like. Not intractable problems to be sure.

I made some homemade cauls out of 8/4 oak and used a jointer.. It takes maybe 5 minutes to make a set.
The curve is more than precise enough that way. Try making some out of 2" hardwood.

My impression is that cauls are not strong enough to force pieces into alignment. It had better fit nice on the dry fitting.

I have no problems with cauls "launching" when I release pressure. If I can't put a clamp in the middle, I alternate loosening each side's pressure..

If you find your homemade cauls a pain to use, I doubt Bowclamps will be any better.
Cauls are a neat idea, but they can't be used on everything.