Scarfing plywood

[clockwork orange]

Oops, i misread, your more like an inch so you want a 300mm setback for 12:1, What the hell are you building that has 25mm bulkheads?
Steve

[cat man do]

Originally Posted by keepondancin

West System (Epoxy) makes a scarfing jig for circular saws.

Only any good for up to 1/4 inch ply if I remember correctly.

I do the clamp and powerplane method and then finish off with a sat180 sander and 36 grit.

I have started using Payson Joints as well

[Blue Stocking]

8 : 1 and 12 : 1 scarfs are usually only necessary for curved surfaces, such as planking. Vertical loaded joints, such as bulkheads, can be much smaller ratios. Butt joint is smallest ratio.

[clockwork orange]

BS, you are quite right, we always refered to a 12:1 as a sparmakers scarf, however if you have the material a larger scarf is better than a smaller one with8:1 being enough for most purposes.
Steve.

[Mick C]

Originally Posted by At sea

Yes, much easier I've found, especially for a hack like me. But as a matter of interest, can you say what you're building?

It's a Dudley Dix dh550...

[Mick C]

Originally Posted by clockwork orange

How many sheets do you have to do? You are going to spend more time dicking around trying to solve a problem that dosnt exist,better to just get on with the job.Thicker ply like that is the easiest to scarf because,assuming you are using good quality plywood of course,it is nice and flat,so just mark a line 9" in from the edge of each sheet(for 12:1) and stack them all on top of each other with each sheet staggered by the 9",clamp the stack together and plane it all off with the electric planer, i start off with a thick sheet that is not going to be scarfed on the sawhorses and line up the edge of the bottom sheet with the edge of this to support it as it becomes a feather edge. You will be done with a whole boats worth of scarfs before your done picking your ass trying to figure out your routing jig. Its a quick process,really.
Steve.

Nice direct advise. I have about 24 sheets to scarf varying from 18mm to 25mm. Most are only a small amount (around 300mm) on to length and width.
Thanks for the feedback.
Mick

[Wand]

Originally Posted by Mick C

It's a Dudley Dix dh550...

Nice boat but sheesh, lotsa work. It'd be nice to see occasional progress pics. Allabest

[capngeo]

From reading the thread, it sounds like a common finger joint would work for the OP's application

[Mick C]

Originally Posted by capngeo

From reading the thread, it sounds like a common finger joint would work for the OP's application

Yes, they would work too...

I'm following Dudley's instructions as much as possible...I like doing what someone who knows the boat better than anyone else...

So let me take the opportunity to say merry Christmas, happy holidays and a wonderful new year to us all.

Mick