glueing up questions

[Anonymous]

Finally got the latest project to the start of the glueing up stage and thought I'd take the chance to reality check some of my behaviour. 2 questions:

How do you make sure work is not twisted when glueing up? and

How do you clean up glue from around mortise and tenon joints?

so far my solution has been to clamp up the work on top of the table of my bestcombi as the flattest, truest surface I have, then weight the whole think down so that it stays flat to the table.

then cleaning up the joints - apart from the obvious don't use too much glue and wipe it off whilst wet/peel it off while tacky, i use a stanley knife blade to scrape away the excess when set - its the only thing I can think of to allow me to get right down into the corner?

anyone recommend any other tricks or tips?

 

[Alf]

How do you make sure work is not twisted when glueing up? ... so far my solution has been to clamp up the work on top of the table of my bestcombi as the flattest, truest surface I have, then weight the whole think down so that it stays flat to the table.

Hmm, sounds like perhaps you're building in the twist at the joint making stage? When you do the dry run, does it twist? Or only when you come to put the clamps on? If it's the latter then you're almost certainly creating a twist by not lining up your clamps on the joints etc. You certainly shouldn't need to weight it down like that :?

How do you clean up glue from around mortise and tenon joints?

Personally I try to apply at least a couple of coats of finish before I glue up. Not only does this stop the glue working into the fibres of the wood, but makes the whole finishing process more controlled. No more twisting yourself into weird shapes to get to that corner just there at the back, and then oh dear the ruddy stuff's gone and run and made a drip... Make sure you mask the gluing surfaces when you do it though; finish on a tenon or in a mortise will weaken, and may even prevent, the gluing process. Alternatively mask the area around the M & T and just peel off the tape and glue. Someone suggested rubbing a line of candle wax along the join to prevent the glue sticking, but you need to make sure it won't interfere with your finish. Whatever you do it's worth having an old, blunt chisel around to use to clean up the overspill. Glue ups eh? Don'tcha just love 'em :roll:

Cheers, Alf

 

[Anonymous]

dry, the joints are not as tight as I'd ideally have liked them - still learning and need a lot more practise. Where I've actually had the worst twisting problems is glueing up drawers with dovetails all round, so habitually now I tend to glue up in this way - check every mortise/corner is square where you can actually get in and check without tripping over a clamp, put in cross-braces where appropriate and then block up to clear the clamps and weight onto these - maybe I'm just paranoid....

I'm working with cherry at the moment so I've always been told to leave cherry unfinished so that it will colour over time - never was sure if its air contact or light that causes it, so the finishing over glue marks isn't a problem with this project (or the next 5 or 6 - working on the whole bedroom set, should keep me going for the next x years)...

cheers

 

[Chris Knight]

Cherry will darken whether you finish it or not. Some finishes can slo down the rate at which it darkens but none stop it.

 

[johnelliott]

Alf is correct (I'm sure he already knew this) it is highly advisable to put some finish on the components before gluing them. Danish oil is ideal for this as most other finishes can be used over it, and it is quick and simple to apply

John

 

[Alf]

Okay, I'm feeling very daft now. :roll: Never occurred to me to use Danish oil; I tend towards shellac these days, but Danish oil would be better in some instances. Thanks, John.

It's the UV that darkens cherry isn't it?

Cheers, Alf

 

[Anonymous]

Chris had previously suggested water-based poly for the tops to protect them from water-rings (these pieces are bedside tables) and I was waiting to place my next axmintster order to get some to try on some scrap....

I've used danish oil on a door threshold i made for a mate and it definitely gives the cherry a nice rich colour...i can foresee a windowsill covered in test pieces in the spare bedroom....

 

[Aragorn]

Twist??? That's down to the joinery as Alf says. May be to do with too much clamp pressure as well maybe?
If your boards are perfectly square-edged and your joints are accurately made, there shouldn't be any twist. If you're not preparing your own timber on the planer/thicknesser I don't think you can ever expect it to be accurate enough.

Glue - I very often use polyurethane glue these days as it's set tight in 5 minutes. It foams out at the joints and cleans off very easily with a chisel. No more waiting for glue to dry with things hanging around the workshop in clamps.

A

 

[johnelliott]

Glue - I very often use polyurethane glue these days as it's set tight in 5 minutes. It foams out at the joints and cleans off very easily with a chisel. No more waiting for glue to dry with things hanging around the workshop in clamps.

A

Which brand of polyurethane do you use, and where do you get it? It really is time I at least experimented with the stuff, though I do worry that such a quick set would make it difficult to quickly pull apart something that was going wrong

John

 

[Aragorn]

Hi John
I use EverBuild Polyurethane Wood Adhesive. They do a 5 minute set and a 30 minute set. I buy it from my local hardware store, but I imagine anywhere that stocks EverBuild can get hold of it. It comes in a gun tube (like Gripfill) and costs around £6.
The 5 minute one is rock solid after 5 minutes! 100% set after 24 hours. I tested it when I first started using it - butt joined 2 lengths of 4x1 together end on end, clamped up and waited 5 minutes. I then jumped on the wood suspended between some bins. No problems!

Always wear gloves with this stuff - it stains skin and it don't wash off.
If you can't find this make, there are others, such as Gorilla Glue, but this is the only one I've found that sets in 5 minutes.

A

 

[woodshavings]

Screwfix supply polyurethane adhesive -
http://www.screwfix.com/app/sfd/cat/pro ... 2&ts=93698
costs about £6 for 310 ml.