Biscuit advice

[chippy1970]

Hi all I have to fit a 12 metre run of Iroko worktops in a school on Thursday Im using 3m x 800mm lengths that we have had made up and today I cut slots in the ends to join them all up in place. The slots are dead on 4mm wide cut with a Wealdons biscuit cutter in a router. When I tried the Trend biscuits in the slot there seemed a lot of play it doesnt normally bother me when Im doing kitchen worktops as you can flush them up as you tighten the bolts, but these are only 25mm tops so I wont be using bolts.

Is their a good way to get them to swell a bit before they are used ? Also we were going to use PU glue but Im guessing PU wont swell the biscuits as well as PVA am I right.

 

[jasonB]

Stick them in some water, not only will it swell then the water will also set the PU off better.

Clean the joints with acetone etc to remove any oild in the wood first.

Jason

 

[chippy1970]

Yeah I did wonder if I should clean with Acetone first. So you reckon PU is OK then ? Ive not really used it much I always stick to the old faithful PVA.

 

[jasonB]

I don't use PU a lot but have used it on iroko external doors & windows and not had any problems but they had a lot more surface area than thin worktop endgrain.

if they are 25mm finish you should still be able to bolt them even if you leave 3mm of the dogbone plates sticking out the bottom. You will still need some way of pulling them together while the glue sets

Jason

 

[chippy1970]

They are between walls so we were hoping to just wedge it all together or I might try some pocket screws

 

[Nicholas Dalberg]

There is no oil in Iroko, teak yes but Iroko no.
perhaps use polyurethane glues that foam, they are quick and very effective. just make sure you get the clamps set up first as poly glues don't always have a long open time from 30 minutes to 45 minutes depending on heat and humidity ie weather, gorilla glue is an expensive trade name poly glue but there are cheaper alternatives try wurth my 2 cents worth from experience

 

[chippy1970]

There is no oil in Iroko, teak yes but Iroko no.
perhaps use polyurethane glues that foam, they are quick and very effective. just make sure you get the clamps set up first as poly glues don't always have a long open time from 30 minutes to 45 minutes depending on heat and humidity ie weather, gorilla glue is an expensive trade name poly glue but there are cheaper alternatives try wurth my 2 cents worth from experience

I think the bottle we have is soudal http://www.marchesironmongery.co.uk/pu- ... 750ml.html

 

[JoinerySolutions]

Soudal, used it and it's good.
Polyurethene glues are moisture activated, so if you mist the edges with clean water it will cure faster. As posted by jasonb the biscuits will swell from contact with water but a complete dunking is not really required.
Hope the job goes well.
Rob.

 

[chippy1970]

Well we started fitting them today and the biscuits in water trick worked well just dunked them for 2 minutes and they fitted fine. It didnt matter much in the end anyway as we put plywood cleats underneath as well.

That glue works well but like people have said it needs dampness to set it off, very easy to clean off when its set too.