Gluing temporary blocks onto piece to help with glue up

[andrew whicker]

Ladies and Gents,

I'm about to finally glue up a coffee table I've been working on for a while. Photos below (some of during construction to get a good idea of what I'm doing). The trapezoid shapes are my concern (lower shelf and main legs). What type of glue do people use to glue on temporary blocks for glue up (in order to clamp two parallel surfaces)? The temporary blocks will be glued to long grain.

Or is there a another way to glue up?

Cheers,

361925

361926

361927

[Kevin Jenness]

A "paper joint" using kraft paper between workpiece and clamping block allows for splitting the block off without damage.

[glenn bradley]

+1 on paper:

http://www.woodworkersjournal.com/making-non-permanent-glue-joints/

Spray adhesives that are non-permanent leave too much residue for my purposes most of the time. The paper removes easily, the glue not so easy but, do able.

[Jim Morgan]

A "paper joint" using kraft paper between workpiece and clamping block allows for splitting the block off without damage.

Two other possibilities:

Make a rubbed joint with hide glue and steam off the blocks afterwards. A little steam cleaner works well for this. I have had best results using hot hide glue, but Old Brown Glue (or the equivalent) will also work.

Or, use hot melt glue to affix the blocks & drip some denatured alcohol into the temporary joint afterwards to break the glue bond. Once in a while I've had a block slip under clamping pressure, so I keep the glue gun charged up to re-fix anything that has slipped.

[Edwin Santos]

Two other possibilities:

Make a rubbed joint with hide glue and steam off the blocks afterwards. A little steam cleaner works well for this. I have had best results using hot hide glue, but Old Brown Glue (or the equivalent) will also work.

Or, use hot melt glue to affix the blocks & drip some denatured alcohol into the temporary joint afterwards to break the glue bond. Once in a while I've had a block slip under clamping pressure, so I keep the glue gun charged up to re-fix anything that has slipped.

I can't speak to James' first suggestion, but I have become a devotee of the second one. Hot glue is like magic, and once I learned that denatured or isopropyl alcohol will reverse it, I use it all the time. Clamping blocks like you need to use, fences and stop blocks to machines and table saw sleds, lots of router operations, on and on.

[Mike Henderson]

I use the paper technique. When finished, you can split the block off with a chisel, then sand the remaining paper off.

Mike

[larry senen]

Veneer tape is also a good protection. And you don't have glue to clean up, important on oak or other open grain woods.

[Wayne Lomman]

There is no need to glue blocks on at all. Cut some angled blocks to suit your job and clamps then glue some 240 or so sandpaper to the face of your blocks to give a bit of extra friction where they contact the job. Alternatively use end grain blocks. They will grip just as well. Don't underestimate the friction grip of timber. Also it has always been a rule in my shops to never get glue or pencil makes on any seen face ever, if at all possible.Cheers

[andrew whicker]

Awesome!

Will try that first.

[Kevin Jenness]

Another method of temporary attachment that works quite well is to stick a piece of blue tape to the block and another to the workpiece, with a light bead of ca glue on one piece of tape and accelerator on the other. I have been using this trick for holding pieces to my cnc router table with good results.

[Jim Morgan]

There is no need to glue blocks on at all. Cut some angled blocks to suit your job and clamps then glue some 240 or so sandpaper to the face of your blocks to give a bit of extra friction where they contact the job. Alternatively use end grain blocks. They will grip just as well. Don't underestimate the friction grip of timber. Also it has always been a rule in my shops to never get glue or pencil makes on any seen face ever, if at all possible.Cheers

Working in a commercial shop where there are several capable hands available to help out is one matter. Working on your own, trying to hold up blocks against gravity while positioning and tightening multiple clamps in a complex glue-up before the glue's open time expires, well, that sounds like a recipe for disaster.

[Wayne Lomman]

Glue up has never been a job for more than one man in my shops, and in recent years where I have been working solo, it is the only option. If I need a hand, I have set it up wrong. I do not expect everyone to do it my way but it doesn't hurt to know that there are options. Cheers

[Jim Morgan]

Yep, knowing multiple methods allows you to choose the best one for a given situation.

[Tony Leonard]

I normally use regular old white glue. Most of the time, I saw the blocks off, then plane the rest off. I have been using this method for miters a lot lately. It really does help (works for me anyway). There are some clamp on type blocks out there that work too. I made some with miter off cuts and hardboard. Those are nice and there is no cleanup involved.

Nice table!

Tony

[keith micinski]

Surprised no one mentioned double sided tape. All of these other methods will absolutely work but they all require you to mess around with some type of glue and the chance of having to clean it up. I use double sided tape for almost every jig or weird thing I make and it has never failed and when your done just peel it off and nothing else needs to be done.

[Curt Harms]

I learned about hot melt glue & DNA doing some solid surface work. I haven't tried it on wood yet. I'm sceptical that hot melt glue would be as strong as a paper joint but I haven't compared them.

[Mike Cutler]

I learned about hot melt glue & DNA doing some solid surface work. I haven't tried it on wood yet. I'm sceptical that hot melt glue would be as strong as a paper joint but I haven't compared them.

Curt
It only needs to be strong enough to withstand the clamping pressure, and not slip out of position. The paper method is strong, and let's face it, cheap, fast, and readily available. I've also glued 220 grit sandpaper to blocks for clamp blocks, and they work surprisingly well.

Each project presents it own unique set of problem. It's nice to have an array of methods to overcome them.

[Al Launier]

Very interesting project Andrew & looks to be very well made indeed!

If I could offer an "amateur's" opinion (compared to those above) I would recommend the following based on my limited experience and, as some are duplications of what has already been stated above, it's only because I've learned these techniques from this and other WW forums and I include them only to reinforce what those above have said:



Glue up smaller sections at a time that don't necessarily require an assembly to ensure a proper final fit. This has proven itself to me many times. Taking on too much at a time can be self-defeating.
Use temporary blocks that are cut-offs from angular cuts made for the parts of the finished piece to provide exactly the same angle for gluing; otherwise cut blocks to the angles needed for a good clamp-up.
Double-back tape has been a strong second pair of hands to hold things together are is easily removed.
Strap clamps are very handy for awkward glue-ups. Strap clamps also include large strips of rubber (ex. those used by nurses for tourniquets when drawing blood), bungee cords, etc.
Although I don't prefer Hot Melt glue for permanent gluing, it is adequate for temporary clamping and is easily removed afterward.


Good luck with your glue-up, that's a beautiful table you made!

[Chris Fournier]

There is no need to glue blocks on at all. Cut some angled blocks to suit your job and clamps then glue some 240 or so sandpaper to the face of your blocks to give a bit of extra friction where they contact the job. Alternatively use end grain blocks. They will grip just as well. Don't underestimate the friction grip of timber. Also it has always been a rule in my shops to never get glue or pencil makes on any seen face ever, if at all possible.Cheers

This right here! And don't forget about good old tape.

[Jerry Olexa]

I've used hide glue in cases like this..Easily removed later after dry.