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fixing forms
By:Paul Jacobson
Date: 5/13/1999, 1:06 am
In Response To: form cutting (Philip Miles)

> This is a slightly embarrasing admission, but being a first time builder,
> I hadn't the confidence to scissor out the form patterns from the plans I
> ordered from Nick just in case I made a hash of it, so I (er!)photocopied
> the form cutouts and used these to make the forms. I understand that it
> probably infringed upon the copyright, but as my intention was purely to
> 'get it right' I didn't feel that it was very important to get permission
> to do this (I should have written and asked, I didn't, I am sorry). As it
> turned out the forms came out really well BUT for some reason the
> photocopied prints were not 100% accurate because my larger forms are
> 1-2mm short on height and 1-2mm long on width at either end, when I
> overlay the forms onto the original plan. The smaller forms are O.K.

> What I want to know is, will this make a noticable diference when I start
> to strip the hill, I really, really dont want to have to go out and buy
> another sheet of ply and start all over, but if I have to I will. Please
> advise.

> Thank you,

> Philip

Slight differences should not be a problem, but you can check to see how slight those differences reall are by simply laying the original plans over your already cut forms. If the forms are larger than the patterns, slide a piec of carbon paper in between the pattern and the wood and mark along the pattern edge to show how much more wood should be removed.

If your forms are smaller than the pattern by 1/16 or even 1/8th of an inch you can probably leave them alone. You can make up the difference a bit by repositioning the form a bit closer to the stern or bow. Maybe slide it 1/4 inch or less from the point where the directions say it should be attached to the strongback. The idea here is that the form will still be the shape of a cross section of the boat, but at a point where the hull is a bit smaller, meaning generally, closer to the ends.

If you decide that the forms are too small you can build them up rather easily by using strips of cardboard (mat board works nicely) tacked or stapled to the outside edge of the form. If your forms are cut from 3/4 inch plywood, use a very sharp knife and a straightedge to carefully cut strips 3/4 inches wide from your mat board. Wrap thaem on the form's edge with a staple at each end. REcheck the form agains the pattern. If it fits, stop. If it is still small, add another strip of mat board. When you have the form built back to the proper dimensions, use some glue and staples to hold the matboard on. After the glue sets pull out the staples. You can use short pieces of matboard and just butt them together to cover the circumference of the form. If you overdo it, after you pull the staples you can use your sander to remove any high spots. The matboard cuts easily with even fine grit sandpaper, so go easy.

Hope this helps.

Paul Jacobson

Messages In This Thread

form cutting
Philip Miles -- 5/12/1999, 1:50 pm
Re: form cutting
Nick Schade - Guillemot Kayaks -- 5/13/1999, 9:44 am
fixing forms
Paul Jacobson -- 5/13/1999, 1:06 am
Re: form cutting
Mike Allen -- 5/12/1999, 4:23 pm
Re: form cutting
Bob Marr -- 5/12/1999, 3:32 pm
Re: form cutting
Mike Scarborough -- 5/13/1999, 8:33 am