Page 1 of 1

Finger Joint Bottom Panel - Misaligned

PostPosted: Tue Aug 14, 2012 8:25 am
by jwv630
Hi Everyone:

Well, I've just about pulled out most of my hair - and I'm only about 5% thru my Pocketship build. I epoxied the finger joint on my bottom panel and apparently did not use enough clamping pressure. Now it's misaligned enough to worry me. I'm mostly concerned about the integrity of the joint, as well as the aesthetics. Your thoughts and suggestions are very welcome and appreciated! Some options as I see it:

*Leave as it
*Buy some plywood from CLC and start over
*Build up the space where the fingers don't meet with epoxy
*Lay down a strip of fiberglass to reinforce the joint
*Take up gardening

Thanks, good luck, and best wishes
Jimmy Vitale
Victory II

Re: Finger Joint Bottom Panel - Misaligned

PostPosted: Tue Aug 14, 2012 9:11 am
by JonLee
One of these days I'll get around to posting photos of my hairline before and after building PocketShip....there's a difference :-)

Do you have any pictures of the misalignment?

Re: Finger Joint Bottom Panel - Misaligned

PostPosted: Tue Aug 14, 2012 11:18 am
by jwv630
Hey Jon:

Thanks for checking in. Here's a link to my blogsite with pictures of the misalignment. http://jimspocketship.blogspot.com/2012 ... ed_14.html
I don't know how to post pictures to this Pocketship.net website yet.

Any thoughts?
Thanks
Jimmy V

Re: Finger Joint Bottom Panel - Misaligned

PostPosted: Tue Aug 14, 2012 11:55 am
by mtsailor
I see two ways of dealing with it. 1) Sand it smooth and fill any gaps, then double up on the glass at the joint to ensure strength that might be lost due to the thinner wood. Once the boat is finished and painted, only you will know there was a mistake under there. 2) Take the joint apart using a heat gun and start over. Should be doable as long and the joined panels are not already stitched into the rest of the boat. Heat makes resin soft and pliable, so start at one edge, heat the joint, pull/twist, until you have all of the fingers apart. Good luck. Jer aka mtsailor.

Re: Finger Joint Bottom Panel - Misaligned

PostPosted: Tue Aug 14, 2012 3:43 pm
by jwv630
Jerry:

Didn't know about the heating technique. Many thank's!

Jimmy V

Re: Finger Joint Bottom Panel - Misaligned

PostPosted: Wed Aug 15, 2012 7:42 pm
by jwv630
I'm leaning towards Jerry's (aka mtsailor) #1 suggestion. Thanks Jer. Plan is sand as needed; then apply 1 or more coats of unthickened epoxy over the areas of the finger joint that are misaligned until the joint is level with the rest of the bottom panel. Maybe a strip of fiberglass for reinforcement also.

Gonna begin tomorrow night so any additional comments and suggestions are appreciated....

Best wishes and thanks again,
Jimmy Vitale

Re: Finger Joint Bottom Panel - Misaligned

PostPosted: Thu Aug 16, 2012 11:03 am
by JonLee
You might want to fair it in using fairing compound like SilverTip Quick Fair (or epoxy thickened with microballoons) instead. The stuff applies really nicely with a putty knife, and sands like a dream. Since these fills won't really be bearing axial loads, there shouldn't be any stength implications...it'll take the shear loads between the 'glass and the plywood just fine.

The fairing compound is a touch spendy, but is well worth the money. Plus, you'll be able to use it to fill holes, fix divots, and fair the outside of your hull later down the road, so it's a good investment. I used SilverTip Quick Fair on my boat and have nothing but praise for it.

Take solace in the fact that on the scale of boat building disasters, this one could have been worse. Unbeknowst to me, I had some plastic wrap sneak into my scarph joints on the side hull panels, the end result being structural failure (http://leeboatworkspocketship.blogspot.com/2011/04/its-starting-to-look-like-adisaster.html) of those panels when I was lifting then into the cradle to stitch them in. I had already 'glassed and sanded them. I had to scrap those panels and scarph, layout, cut out, 'glass, and sand all new ones. I'm glad they failed when they did, though. If I had filleted in the bad panels...

Re: Finger Joint Bottom Panel - Misaligned

PostPosted: Thu Aug 16, 2012 3:40 pm
by jwv630
Hi JonLee:

Many thanks for your advice. And good call on the SilverTip fairing compound! I just ordered some from DuckWorks.

Best wishes,
Jimmy V