Plano-type Panel Clamps & Benchtop Epoxy Glue-Up?

Does anyone here have a set of these? http://www.ptreeusa.com/panel_glue_up.htm

My wife gifted me two sets when they were on a 40% off sale. I haven't used them yet but have mounted them to a 2x attached too a wall and together they'll give about 7' of clamping length. They claim to work from thin to up to 5" thick. When I first saw them I immediately thought of a benchtop to break them in. <g> I'd planned on adding a Bessey K-type between each of these clamps, plus one or two on each end.

I'm planning on a thick (4"+/-) top, 36" wide.

Also, I'm looking at using epoxy for the glue-up, since these clamps are designed for gluing up all 24 pieces ay once and I'll be working alone. I'm looking at West Systems epoxy http://www.westsystem.com/ss/hardener-selection-guide/ . With their 209 extra-slow hardner I'd get a 3-4 hour thin-film working time and 20-24 hours to cure to solid. Since I'm in no rush, lucky to get a day a week in my shop, in the clamp and up against the wall seems like a good place to "store" it for a week or so. I *was* thinking that I should probably line the clamps with waxed paper to keep any squeeze-out from making the clamps permanently attached. <g>

I'd sure appreciate any feedback or thoughts you may have on this!

Thoughts?

And I thought Bessey clamps were expensive.

How are are you planning to construct the top, by sandwiching ~2x4 boards together? How fussy is it to get these clamps wrapped around the boards? Figuring you need a clamp every foot or so to get good clamping pressure throughout 36" x 8' (?), it's a lot of clamps to get set up before the glue starts to harden... bearing in mind the glue on your first board will be starting to cure as you keep adding more boards and then applying more glue. But if it doesn't take any longer than tightening a bar clamp, and you use a glue with long open time (probably a good idea anyway), then it would probably work well. It does seem like these would do a better job aligning the boards along the wide surfaces.

edit: (noting your edit about considering epoxy). Not to discourage you away from the epoxy if that's what you want, but just in case you're not aware, Titebond makes a version of their yellow glue called Titebond Extend with an assembly time of about half hour. I used it on my workbench.

Yea.. She got them for me when she saw me looking at them and then saw them at 40% off and got me 2 sets... Who am I to complain at receiving more toys... er... tools.

Yes, that was my planned construction technique.. stacking up ~4" wide 8/4 maple. As far as fussy, with the adjustable lower support in place the one vertical attaches to the cross-member and the other seems to lean out about a foot and stop, as if the glue-up might be a piece of cake. I don't know as this will be my first use of them. Nevertheless, before trying maple I think I"ll rip some 2x4's for a test glue-up since I can buy fir for a small fraction of maple.

It'd also make a good candidate to learn how *not* to mount the vises. <g>

The long set-up time is what drew me to the epoxy... I figured that with 3-4 hours working time even I should get it done!! I'd considered Extend but I figured the more time the better, unless there's a good reason not to....

Also, I've picked up a 3" paint roller and am thinking about trying to use that to spread the stuff. Anyone have comments??

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Originally Posted by Andrae Covington

And I thought Bessey clamps were expensive.

How are are you planning to construct the top, by sandwiching ~2x4 boards together? How fussy is it to get these clamps wrapped around the boards? Figuring you need a clamp every foot or so to get good clamping pressure throughout 36" x 8' (?), it's a lot of clamps to get set up before the glue starts to harden... bearing in mind the glue on your first board will be starting to cure as you keep adding more boards and then applying more glue. But if it doesn't take any longer than tightening a bar clamp, and you use a glue with long open time (probably a good idea anyway), then it would probably work well. It does seem like these would do a better job aligning the boards along the wide surfaces.

edit: (noting your edit about considering epoxy). Not to discourage you away from the epoxy if that's what you want, but just in case you're not aware, Titebond makes a version of their yellow glue called Titebond Extend with an assembly time of about half hour. I used it on my workbench.

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If you want the best bond you can get use some pieces of scraps to make splines placed in between each board..

I seen some glue tests and tite bond did work as well as epoxy on bare wood and good fits..

I've seen those tests too, Johnny... I wasn't looking at it for extra strength. I just really like the idea of several hours of working time....

I've heard talk about installing splines in benchtop design but it was touted to prevent the boards from slipping out of alignment. when you've got 3"x84" of edge-to-edge glued up, that's a lot of surface area. Are splines really worth the hassle and delay and will you get more strength? The panel clamps I linked are supposed to align as they tighten.

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Originally Posted by Johnny Kleso

If you want the best bond you can get use some pieces of scraps to make splines placed in between each board..

I seen some glue tests and tite bond did work as well as epoxy on bare wood and good fits..

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I'll toss in my thoughts. I think I would glue up the top in 3 or 4 sections. This would allow you to not have to worry about excessive open times. It would also help with moving things around which will inevitably happen, and make it easier to get everything flat. Then when gluing up the 3 or 4 big pieces, I would consider using the splines. I would be a bit concerned that with such a heavy glue up the clamps may have a hard time getting them lined up. The splines would be some very nice extra insurance, and it would not be to difficult to line up 4 splines.

I have no clue about the clamps but you have one terrific wife. Does she happen to have an unmarried sister?

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Originally Posted by Andrew Gibson

I'll toss in my thoughts. I think I would glue up the top in 3 or 4 sections. This would allow you to not have to worry about excessive open times. It would also help with moving things around which will inevitably happen, and make it easier to get everything flat. Then when gluing up the 3 or 4 big pieces, I would consider using the splines. I would be a bit concerned that with such a heavy glue up the clamps may have a hard time getting them lined up. The splines would be some very nice extra insurance, and it would not be to difficult to line up 4 splines.

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Even with these clamps, Andrew? They look like they're *supposed* to do the alignment for you.

lol!! I *am* mighty spoiled!!

I think splines like a big long biscuits would only help making the top stronger..
When I made my top I made it in sections and did not glue all boards at once..

Router two grooves down each board from the same side and mill up some keys would make thinks cake putting them together..

I'm no expert, but----

I love epoxy, and West system is about the best. However, couple things to keep in mind. one is, unlike most glue, you don't want to clamp epoxy joints tightly. You actually want a slight gap. something about the epoxy sticking to the wood rather than really soaking in. Lots of joints I do with epoxy, I just rely on gravity. for a workbench, I think you want tight joints. Of course, if you do go with epoxy, you can always fill in the gaps with epoxy. Cool thing about it is that it doesn't shrink as it dries, so once the top was epoxied up, you could put on a skim coat and you'd have a bartop like surface. Course, that might not be the surface you'd want.

Second thing is, epoxy is going to be about 10 times as expensive as glue. plus, you're going to want lots of supplies. mixing pumps are a MUST if you have any concerns about time, plus gloves, rags, spreaders, mixing cups, acetone for cleanup. Expenses go way beyond the actual resin and hardner.

third thing is, read the safety info from West before you decide to do this indoors, especially if your shop is in your house. If you do use epoxy and you are indoors, give it at least a week to dry before you do any sort of sanding.

Again, I'm no expert, and if you do use the epoxy, I'd love to hear how it goes.

I have considerable experience glueing up large panels. The boards will move in relationship to each other because of the lubrication of the glue and at some point it will "catch" and stop moving. I have never found a clamp / caul system that will make this movement predictable. If one board in your top moves 1/32" one way and any other board moves 1/32" in the other direction, then you have 1/16" of surface to remove from the entire top just to get it initially flat. And you have to remove 1/16" from the back side if you want it to be flat...so, there's 1/8" total thickness lost from two boards moving 1/32."
For me, splines are usually important insurance. A table saw is really good at cutting grooves. Splines can be good-quality 1/8" ply. Even a few small splines will add considerably to the strength of edge joints and will retard splitting at the joints. If there's a lot of surface area it will be redundant.

Dap Plastic Resin Cement will give you all the open time you need too. And maybe cheaper and easier than epoxy. Your week long wait is perfect for curing this, but you've got to keep it warm.

As I understand it, the slick way to use these ... and maybe this doesn't work with thick pieces ... is to set your first piece in the clamps and then stack the rest in front of it, laying against the front rail, in the reverse order and orientation they'll get glued. Apply glue with a roller to the top piece in the stack, flip it over, and move it to the back. Repeat until you run out of pieces. This allegedly goes really fast.

I can see how thick pieces wouldn't fit double wide, but maybe stacking them on a strip of plywood at the bottom will let them clear the bottom piece.

I don't think the glue is your problem - doing the glue-up using the Planos on your own could well be. I have some, and I like them, but personally I wouldn't dream of using them on a thick bench top unless I knew I had help on hand. And help that I'd gone through a dry run with first so we both knew exactly what the plan was. Have a practice dry run with any old stock on hand and see what you think then, is my best advice.

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Thank you, Alice... I've been *wondering* about working alone. I want to make a prototype top out of fir before making the final one out of maple (~6x the price) in order to test my vise mounting idea, possibly making a router jig for the bulk removal. Better to goof that one up. Besides, since I'm currently working viseless off of a collapsable table, I can put the first top over sawhorses and use it when making its successor!!

I would appreciate knowing your concern on working alone, given your experience with the clamps and my inclination on materials:

I'm thinking about building this out of kiln dried fir 2x8's (1.5"x7.25"), edges trimmed (to get sharp corners) and each ripped to two pieces 1.5x3.25".

The test-top would be made from 24 such pieces, each on edge, resulting in a top about 36" wide x 3.25" thick.

I hadn't (at least yet) considered (which was naive / stupid of me) test-stacking and clamping the pieces together prior to adding adhesive.

My idea was to line each of the clamps with waxed paper to avoid the wood adhering to the clamps.

With the first piece in the clamp assembly, I'd mix up small batch (50-100g) of West System epoxy with their 209 extra slow hardner. From their hardener selection guide (attached) they claim the pot life of a 100g cup is 40-50 minutes. This would then be poured into a paint tray w/disposable liner [to let heat escape and slow curing] and applied to the face of the second board using a 3" paint roller. This board would then be carefully aligned and set in place. A third board would then be glued, etc.

Their selection guide claims a working time of 3-4 hours. Allocating 5 minutes to apply glue to each strip and place into the clamp, two hours would have ellapsed by the time the last board was in place. I was figuring that'd give me an hour to finalize the alignment and clamp before reaching the early side of the claimed working time.

I'm far from overconfident about this process and welcome feedback but this doesn't *seem* prone to pitfalls. Somehow making a table top seems like it should be a two-person operation but for this... I'm not sure. Your thoughts?

This may have been hinted at already, but...An old timer offered me some advice a while back. It was to make one glue joint at a time. We were talking about the table I made for my kitchen and the trouble I had in keeping the top flat. I made a couple of cutting boards, following his advice, and found that he was spot on. For my next table top, I will join two boards. Then the third. Then the fourth. And so on. It is easier to control one joint at a time than four or five.