joining thin boards

[cerdeira]

hello all.

I need to join some boards to make some panels with a thickness of 7mm.
Due to some limitations in my timber supply I must use 3 or 4 boards to
make up for the required panel width.

I've glued up thin boards before but only in pairs and struggled a bit to keep
them aligned and to avoid the whole thing to snap up while applying clamping pressure.
Now, I'm afraid that the glue up of such a number of thin boards will be troublesome.

I've thought of gluing the panel in steps: 2 boards, wait to set and glue the remaining ones.
Also considered cutting a 3mm groove on the edges and using a spline to help stabilise the boards.

What do you suggest?

TIA

 

[Racers]

Hi, cerdeira

Try clamping them loosly to a couple of batterns, use parcell tape to stop them sticking, then clamp up as normal.


Pete

 

[Chems]

Alternate the clamps top to bottom helps. I'd get them in place with light pressure then get a couple of lengths of 1x1 and place these over and under and clamp them down vertically before applying pressure horizontally. Remember you don't need that much pressure if you have a good straight edges.

So you end up with something that works like this:

 

[woodbloke]

Thin boards across a wider width require a different strategy. I'd use an mdf base board (well waxed) with a series of finger operated cams along the length to apply pressure. Any bowing of the completed assembly is then far easier to correct by cramping to the baseboard.

The other thing to ensure is that the edges are shot dead square...I'd use a long shooting board for this and a No7 (if I had one) - Rob

 

[bugbear]

hello all.

I need to join some boards to make some panels with a thickness of 7mm.
Due to some limitations in my timber supply I must use 3 or 4 boards to
make up for the required panel width.

I've glued up thin boards before but only in pairs and struggled a bit to keep
them aligned and to avoid the whole thing to snap up while applying clamping pressure.
Now, I'm afraid that the glue up of such a number of thin boards will be troublesome.

I've thought of gluing the panel in steps: 2 boards, wait to set and glue the remaining ones.
Also considered cutting a 3mm groove on the edges and using a spline to help stabilise the boards.

What do you suggest?

TIA

Check out the techniques used by luthiers to glue soundboards.

BugBear

 

[xy mosian]

I've used rubbed joints on 3mm edge joints with the only sideways pressure applied with masking tape, very successfully. True everything up, apply just sufficent glue and rub the parts together. Place on a flat surface and use lots of short lengths of slightly stretchy masking tape across the joint on both surfaces. Work in pairs, then join pairs together etc.. Shoot up mating pairs of edges before gluing any.

HTH

xy

 

[Mr T]

Hi

I would agree with XY on this.

My system is to shoot the boards to a good fit. Lay them on the bench and stretch masking tape across each joints at about 250mm intervals. Stretching the tape while applying helps to pull the joint together. When you are happy the joints are nice and tight apply a strip of MT the length of each joint.

If the assembly is not too unweildy turn it over and flex the joints to allow application of adhesive along the joint using a nozzle, flexing can be done by hanging the pieces over the edge of the bench if you are careful. Apply strips of MT along the length of the joints, checking they are all flush at the same time. YOu could weight the lot down with batons if necessary.

I have used this system for jointing 0.6 and 1.5mm veneer and also for drawer sides 6-8mm thick.

Chris

 

[gasman]

a domino with 4mm cutter would do it - just about although you would only have 1.5mm on eiher side

 

[mtr1]

G-cramp on the joins at the ends, keeps it alined too..... simples

 

[BradNaylor]

I edge jointed two pieces of 6mm veneered MDF for the back of a cabinet yesterday using the technique Mr T describes. It seemed to work OK but I guess I'll find out for sure in ten minutes or so when I get to the workshop.

Yes, and it is half four in the morning. I want that cheque in the bank today!

 

[Mr T]

The problem with biscuiting or dominoing boards that thin is that the biscuits/dowels can telegraph through and show as depressions or bulges in the surface.

Chris

 

[Mr T]

Hi Brad

Never tried it on MDF, not sure if the gluing properties are the same, how did it turn out?

Chris

 

[cerdeira]

hi,

thanks for the replies.

I'll give masking tape a try. I'm a little bit skeptical about its ability to "clamp" 400mm long edge joints together.
So far I've only used it to glue back small broken chips when doing wood carving or in restoration. we'll see how it goes.

failing that i think i'll revert back to using a spline. I don't have that many clamps to afford clamping all the panels to battens in order to keep them aligned.

 

[Racers]

I don't have that many clamps to afford clamping all the panels to battens in order to keep them
aligned.

You need more clamps then :wink:

Pete

 

[Chris Knight]

Clear parcel tape works quite well too. It is strong and stretches enough to allow you to pull the boards together quite tightly.

 

[jimi43]

Shoot the boards first and candle them to see if ok.

Use good masking tape to join one side all the way down with the boards held in a slight V.

Then lower the boards onto a flat (MDF) surface thus slightly stretching the tape...batten across and clamp battens to hold the boards flush across the width.

Allow to dry overnight at least until perfectly cured...not just set.

Jim