scarfing ?

[wingnut]

well, i've started my project a tracy o'brien H-16, power dory. i've just started scarfing the bottom panels. i scarfed two bottom sheets of 1/2" plywood together and pulled the clamping board (that's what i call it anyway) off and found that i have about an 1/8" gap between the two sheets (meaning one sheet sits about an 1/8" higher than the other side) i thought i had been extra careful when aligning and clamping but the sheets must have moved some.
so here is my question: is an 1/8" to much or should i just mix up some epoxy filet and taper it out and do some sanding for a smooth flush surface or should i cut the scarf out and try another attempt. i have since scarfed up another panel and it looks a lot better and no slipping. this bottom panel will not really be seen since i will end up putting another layer of wood on the bottom and a floor in the boat as well so, i'm tempted to just taper it out with a little epoxy and keep on going.
what do you guys think? (i know this is a hard question since you can't see what i'm looking at)any advice would be appreciated.
wingnut

[Ian McColgin]

The joint just slipped due to weight.

Cut on either side of your scarf, replane and reglue.

This time keep the pieces from slipping by tacking the sheets either to the floor (thourgh your plastic that keeps you from gluing them down) or to each other.

G'luck

[On Vacation]

Sight down the edge of the two pieces scarfed together. It will probably be crooked or not a true line. I don't know how this will effect the cutting out of the pieces you have, but in the future, dry fit your pieces and mark the joints across them. Sight down to make sure your pieces are aligned straight along the edge when you do this.

Remove them, mix the glue up and apply to joint and place in the rough area that they need to be. place a screw on the edges of the plywood on both pieces at the ends of them before you clamp them. It is hard to say that you really don't need to redo them, depending on the length require in your parts. IF you are doing this on a floor, then place them on two other sheets of whatever plywood with plastic at the joint area.

[wingnut]

ian,
i should have clarified a little more, i did have it tacked down, but i think it slipped as or right before i tacked it down and didn't notice it until i pulled the clamp board off. on the latest sheet i took more time and was a lot more carefull and double checked everything before and after tacking the panels down.

on another note, it thought this is what i might hear regarding recutting it and doing it again.
wingnut

[Rosebud]

We usually fit the scarph dry, clamp it and drill a few small holes in the scarph for finishing nails to hold the joint. The two boards get mighty slippery when the glue is put on and you try to clamp them. If you drive nails in the pre-drilled holes before you tighten the clamps, then the scarph won't slip.

Good Luck!

[NormMessinger]

I think you can saw a kerf along the scarf and not loose much doing as Ian suggests. If you fair it you'll have a thick spot. If you grind it down flush you have a thin spot. You'll hate like crazy doing it over but it'll bugg you from now on if you don't do it right.

[WOODZOWL]

Wingnut
Been there , dun that , got the tee shirt!
One thing that I have done in the past, when I had a scarf that I did not like, was to put a 6" strip of 6 to 8 oz. cloth on the seam, then fair it while the panels can be laid flat; before you put it all together. Lately even with good scarfs, I have been taping the seams in and out to help prevent the seam from showing up when the first hot sun hits it. The last post you said that a 3/4" composite ie, 1/2 plus 1/4" bottom will be used; GOOD IDEA. The boat that I built in 1990 used a 1/2" bottom, we are now going to add another 1/4" to it. It's a lot easier to do it now in new construction, rather than a retro.
Good Luck J.M.

[wingnut]

well, after reading just a couple of responses it confirmed what i knew i had to do. so this weekend i cut out the bad joint and redid it. like some of you had said, i could have probably gotten away with it but, it would have always bothered me, and the more i looked at it the more it bothered me so i cut it out and redid it, was a lot more careful and did more than one dry fit. Well, i looked at it this morning and am happy to say the new joint (along with couple of others i did) turned out just fine. i happy now with my results.
Woodzowl,
re: the doubled bottom, after talking to tracy about the bottom when i bought the plans, he highly recomended doubleing it up and it makes a lot of sense. and i bet your right that it's much harder to retro fit it. let me know how it turns out.
Wingnut

[NormMessinger]

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