How about plastic shower curtain rod covers over the black pipe or spring for galvanized.
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How about plastic shower curtain rod covers over the black pipe or spring for galvanized.
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There's nothing wrong with galvanized pipe..
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Originally Posted by Robert Engel
Gee, I sure wish I was as talented as you
[OP]
Contributor
Jack, you use actual pipe, not conduit, don't you?
"All that is necessary for the triumph of evil is that good men do nothing."
“If you want to know what a man's like, take a good look at how he treats his inferiors, not his equals.”
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Never used conduit. It would be hard to imagine the treads holding up to maximum pressure.
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I think there is a lot of confusion on what is enough and too much.
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After purchasing a pipe clamp (using Al) from a thrift store, I outfitted a few other pipe clamps with Aluminum pipe. The "grips" eat into the Al pipe just a little but get good grip easily. If used daily, these Al pipes would need to be replaced in a couple years. I am an infrequent woodworker, so they'll last me a decade, at least. The lighter weight is very noticeable and iron pipe on the bottom clamps with Al pipe over the top might be a good answer when lots of pressure is needed. I have personally bought several Aluminum bar clamps (rectangular-shaped bars) in the past year. I bought them from the cheap Chinese tool store then outfitted them with an internal piece of wood (the Paul Sellers method). Additionally, I hot glued some thin 1/8" birch plywood to the jaws for a cushion. They work fine if the joint is already a good fit.
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Some great advise here...
and thx too for the Piher clamp link, was not aware of this brand.
I agree that the amount of force required varies based on how well the edges are straight and flat...not always as easy as it sounds. And even when accomplished, within a few hours after jointing, wood can move quickly.
In theory, if the edges are perfectly flat and straight, no clamps are required, a rub fit will suffice. In the real world, nothing is that straight and flat. Titebond recommends up to 250psi at the joint line, that is a lot of pressure. This is not for the glue, but to asssure the edges touch each other and gaps are closed, this is what gives glue the highest strength bond.
For 1 inch thick material for simple math, 4 ft long boards, this is 48 sq in., or approx. 10K lbs of total force, max., at 200psi. How many clamps, depends on how much force each clamp can exert. I have tested a lot of parallel clamps, they vary greatly, from 500lbs to 1500lbs, such as the new Bessey and Yost tilt handles. With the Bessey, u must insert the rear hex with ratchet to go from 900lbs to the 1500 lbs, but it only requires 1/4 turn. Assuming 500 lb clamps, this is 20 clamps, one every 2.5 inches!! With 1500 lb clamps, its 7 clamps, one every 7 inches.
This might seem extreme, but the numbers fall quickly as not many use 1 inch material. using 1/2 inch material, you can cut the clamps in half. If your wood is freshly jointed and relatively straight, you can reduce clamp force down to 100psi, so cut the the clamps in half again, so only 1/4 the clamps above. So with 1500 lb clamps, 4ft boards, now only 2 clamps vs. 20 clamps! If its soft wood and well jointed, a single clamp and a caul will suffice.
This demonstrates just how critical the variables are when determining how many clamps to use. Eyeing the boards during dry fit, should give you a feel for psi required... if I see gaps, 200 psi, if boards look dead flat, 60 - 100 psi. For softwood, I use the low end, if wood is very hard, I use the higher end. This is why a single clamp with a caul is sometimes appropiate, and other times, clamps every few inches is appropiate.
BTW, if anyone is looking for bargain parallel clamps at max pressure, the BEST I ever tested are the discountinued Yellow STanley Bailey parallel clamps. 1500 psi with simple hand pressure, no tools. No other parallel clamp accomplished this except the Yost tilt handle heavy duty parallel clamp available on Amazon. Too bad Stanley stopped making them, I cherish the ones I have. they pop up used occassionaly. The worst of the ones I tested were Jorgensen and Pony, about 400 psi. So not all parallel clamps are created equal. Of course, this force is mostly only required for panel glue ups, most other tasks never require much force, so nearly any clamps that fits, will suffice.
Here is pix how I test the clamps. BTW, this test shows how clamps loose their pressure over time. This clamp went from 1k psi to less than half in 2hrs. So if you use longer setting glue, re tighten the clamps every couple of hours. A 1/8 of a turn can add 400 psi.
A lot of people ask me where I bought this gage, I bought it 14 years ago, I forgot !
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Contributor
In real life the number of clamps required, and their position, is determined by watching the squeeze-out.
"Anything seems possible when you don't know what you're doing."
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Width,length.thickness all play a part of an assembly.
Member
On a 2 board glue up that is 36" long I use 4 clamps. Good to go. I'm not killing the screw with pressure. Failure is extremely rare, usually caused by low temps.
Contributor
the more glue I apply the more squeeze out I get, I dont always uniformly apply the exact same amount of glue.
Speaking to a Titebond engineer at a trade show, he mentioned, its nearly impossible to starve the joint from glue, due to squeeze out. That was 10 yrs ago, and since then, I start applying clamps more methodically....
Contributor
This is the reason I don't have glue line nor so called glue creep. When someone says you can starve a joint on titebond I just move to the next post....
If you don have enough clamps you have to really think of how you will get good pressure across the joint. If you have enough, then use enough...
I'll use as many as I can get on there..
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Last edited by jack duren; 01-16-2020 at 1:48 PM.
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[QUOTE=jack duren;2983379]This is the reason I don't have glue line nor so called glue creep. When someone says you can starve a joint on titebond I just move to the next post....
Yep, the Titebond guys say they have NEVER seen a "glue starved joint".
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Last edited by Mel Fulks; 01-16-2020 at 2:17 PM.
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[QUOTE=Mel Fulks;2983385]Sorry I don't get pictures. You'll have to set up a link.
What would I be looking at ?
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