Finger jointing marine ply

[booky]

I make commercial boxes from 9mm marine ply and am presently butt joining and stapling.

All wood is covered in material but I want a stronger joint but must also be quick. Considering having some uncovered boxes so appearance may come into it later but again time is money!!

New user after WWW 2007!.

I liked the HEGNER comb jointing machine - expensive?(MIK) but worrying about splintering.

[echnidna]

a festool domino might be a better choice

[booky]

Hi, Thanks for the reply. Saw the Domino! Haven't really used my biscuit joiner yet and it is already outdated!! I had thought of diagonal cutting the boards and using a 00 biscuit.
Still would like the joint to be visably appealing to stimulate me to make some boxes that can be stained (not covered as the standard product is).
Been searching google and have seen dado blades on a saw bench, thinking saw blades with triple cut may reduce splitting/chipping? more than a router?

[Pusser]

Hi,

Ive been using dado blades (Freud) on plywood using rebated joints and a zero clearance blade. It is very quick and gives a very clean joint. As you are doing edges you dont even have to get the dado set exactky the same as the plywood. You use a sacrificial face on the tablesaw fence and you can adjust using the fence. Once set up it is nearly as wuick as cutting sheets (slightly slower feed but not that much).

pusser

[scooter]

Booky, good to have another member from out our way :)

Did the Hegner use a spiral cutter & backing boards? These would be necessary I reckon for working with ply for nice clean joints. The spiral bit would have to be solid carbide though I'd reckon (I think some are HSS?), the glue in the ply would blunten the bit too quickly otherwise.

I assume the Hegner gang cuts the pieces all at once, that would be the only way for production work IMO.

Otherwise, a well made router table with a precision fence like an Incra would enable you to gang cut box joints rapidly.


Cheers..................Sean

[Pusser]

...

Considering having some uncovered boxes so appearance may come into it later but again time is money!!

....
You might consider a mitre lock bit for mitred corners at speed without having to cut mitres then splines of dominos. Ply shoud give reasonable glue strength.

Pusser

[bsrlee]

If you can find someone selling their Triton router table cheap, the Triton finger jointing jig works quite well, but just about everyone who buys one uses it a few times and then goes on to something else.

[booky]

You might consider a mitre lock bit for mitred corners at speed without having to cut mitres then splines of dominos. Ply shoud give reasonable glue strength.

Pusser

Hi Pusser,
Only 9mm wall thickness - not too thin? Getting a price on multiple dado blades as have a spare sawbench with a long shaft.
ta booky

[Pusser]

Hi Booky,

Not sure on the 9mm being too thin, smallest I have done is 12mm and I imagine the initial set up would be tricky. Only offerred it as an option fo rlater when you might consider uncovered boxed. 9mm will be a challenge to get right in a production run whatever you choose (warps ect) - it becomes box making then I think! for the covered boxes Dados are the way to go - the sheet material can be held flat on the sawbench and the sawfence is a good stable reference. A zero clearance plate and a good dado (freud?) cuts extremely cleanly.

Pusser

[booky]

I brought the ZFG Hegner finger jointer and got the coated carbide cutter(s) but cutting one slot at a time is too time consuming for the quantity I need to make and ongoing.
Can I set up 5 sets of dado's? Only need to cut 9mm deep and like the 6mm wide cut I was getting from the Hegner. Could use 6" blades to increase gearing but would loose blade speed .

thanks
peter