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Potterage
19th May 2005, 12:57 PM
I intend to scarf 30 x 9 mm W/R Cedar 'end to end' to make up 5.5M lengths.
The question I am asking, does anyone have some ideas on making a jig so I would be able to scarf multiple lengths at once. I have some ideas but as the old saying goes "why reinvent the wheel" I am looking for two jigs one for actually cutting the scarfs, maybe using a power planer. One for clamping multiple lengths while the resin glue is drying.
I have already seen the designs in 'Bingham's Practical Yacht Joinery' and 'Gougeon Brothers Boat Construction', but these are mainly for using a router.
Paul

bitingmidge
19th May 2005, 01:03 PM
Can't help with the jigs, but I use a couple of 1/16" (or thereabouts) hole drilled through the scarf and bamboo skewers "nailed" in to locate the two bits. Stops them sliding around while you clamp them.

Cheers,

P

Daddles
19th May 2005, 02:13 PM
9mm isn't all that thick. It'd be quicker and easier to do them by hand unless you are doing a lot.

I've seen a lot of jigs around on the internet but they all seem to take a lot of mucking about and are really only suited to mass production. Do a search on the Wooden Boat Forum. I've seen jigs on there (a long time ago, but it's been a long time since I went there). There's time involved in making the jig, and most I've seen seem to take a lot of mucking about to use.

Seeing your planks aren't all that wide, and they are all the same width, you could try nailing a pair of cleats to your bench top to locate the plank. Fit two rods to your planer and a ramp at the end of the bench. The idea being that you drop the plank between the cleats, clamp it in place, run the planer down the ramp and you've got your scarf. Hell, it might even work :D And if it only proves to be rough enough, a bit of cleaning up with the hand plane is easier than you think.

Personally though, I'd go out in the shed first, cut a scarf with your planer, then dress it with your hand plane and see how long it takes. I'm betting that it won't be very long and so you'll need to be doing a llllooooottttt of scarfs to make a jig worthwhile.

Cheers
Richard

graemet
22nd May 2005, 09:55 AM
When making Teepookana, I needed to scarph lots of 30x9 planks. I made a "jig" in a U cross section the bottom of the U was about 40mm inside and the sides were tall enough to take 6 or 8 planks stacked. One end of the jig was cut 8:1 slope and the planks were clamped, staggered back so that bottom of each plank was visible past the slope. The whole lot was then planed down to the 8:1 slope with an 80mm hand held Ryobi planer. It usually took a bit off the jig at the end of each run. It doesn't matter if the angle changes between batches slightly as long as you do an even number and glue the planks from the same batch together.
To glue them up, I made another "jig" (it seems a bit pretentious to give them the same title as Sturdee's creations) which was 2 pieces of timber fixed in an L section about a metre long, about 40mm wide at the bottom and, again tall enough for 4 planks. I lined it with a bit of GladWrap, glued & assembled the first scarph with the top plank about 1/2 mm too proud, drove a 15mm panel pin through the join into the jig so that the back held the two bits of plank straight. This meant that when the clamps went on, the whole lot slid down into perfect alignment, the cedar was soft enough for the panel pin to angle slightly. Put a bit of gladwrap over the join, and assemble the other scarphs on top with more plasic between each one and nailing the panel pins into the previous layer. Then a piece of 50 x25 on top wit 2 clamps over the whole thing. Just before final tightening, give the lot a tap with a hammer against the vertical back bit so that everything is straight. When the glue has set, the nails pull out easily and are filled with the primer coat of epoxy later on. http://www.woodworkforums.ubeaut.com.au/images/icons/icon7.gif

sinjin1111
22nd May 2005, 06:24 PM
I used to scarf 4mm ply sheets 4' wide. After doing them by hand for a few yrs i mucked around with a rig for a router. it took all 10 minutes to do them with a router but 1-1 1/2 hrs by hand. Your hand plane had to be razor sharp so you didn't get tear on the sheet edges. The scarfs were around 60mm wide over the full width of the sheet. So what i would do use a router if you have lots to do. Its very quick and very accurate
sinjin

Potterage
27th May 2005, 10:24 AM
Thanks everyone for your help, a few people have suggested using a mitred finger joint you can pick a cutter up for about $100 but I dont want to buy it before I know that it will work on W/Red Cedar 30 x 9. Any thoughts?
Paul