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Re: Strip: Cut off and re-glued tops of forms
By:A. Edie
Date: 5/21/2014, 12:34 pm

Hello again,

The masking tape, I suggest, should cover the entire first hull sheer strip. That way, any color transition at the tape edge due to the differing epoxy timing will just seem like part of the difference in color between strips.

As you observe, if you proceed as I suggest, the masking tape will be trapped under glass along the sheer of the hull once the hull is glassed. In order to get the tape off, you will need to thin the glass at the edge of the tape furthest from the sheer joint. This will allow you to peel back the tape, bending the very thin glass left at the edge of the tape, and trim the scrap glass and tape off with a knife. If you try to remove the tape without thinning the glass, you will rip the glass free from the hull surface in places, which makes for extra work and a messy joint.

At this point, some context may help. When you prepare to apply glass strips over the hull/deck joint, you will, in my opinion anyway, want to feather the edge of the glass already on the hull so as to have to a smooth surface under the strips where they overlap the hull glass. If you don't feather, the the glass strips will form a bump where they overlap the hull glass. This bump would make for extra work in smoothing the joint, and importantly, could result in you seriously weakening the joint by removing actual glass to get rid of the bump. So, you need to taper the thickness of your hull glass from full thickness on the hull, down to zero where it will meet the bare wood strip remaining after the tape is removed. What I am suggesting is to make this taper before removing the tape. Once you taper the glass to near zero at the tape edge, you will be able to peel the tape back, and the very thin glass left at the edge of the tape will break at the point where it is bonded to the hull. Once that happens, the scrap glass and tape can be easily cut off with a utility knife. When trimming with the knife, angle the blade so that the cutting force is pulling along the hull surface toward the joint, not toward the bottom of the hull. Once the scrap glass is removed, the edge of the hull glass can be sanded smooth to the surface of the wood.

The taper itself can be accomplished by any number of means, ranging from a belt or disc sander (not recommended), hand sanding (painfully slow), or scraping with a carbide scraper (my preference - good control, but reasonably quick results). If you like, you can taper all the way until you are starting to cut into the edge of the tape. In any case, what you should be left with when you are done is a smooth transition from the glass to the bare wood. Depending on how the joint sits once the deck is attached, you may need to feather the glass on the deck too. Bottom line is that you want a smooth surface under the glass strips over your hull/deck joint, at least on the outside boat surface. I glass the joint surface on the inside of the boat first. That way the joint is secure while I do the final smoothing of the outside of the joint. Feathering is not needed on the inside joint surface, as long as you do not try to smooth the joint thereby cutting into the glass you apply over it.

On your next boat, you might want to consider using staples for the hull. Doing so allows removal of the hull without disturbing the forms, which eliminates the hassle and potential risks of re-aligning the forms after knocking them free. Just a thought. :)

I should note that my experience is with an internal strongback. If you are using an external strongback, you will be dealing with slightly different issues, particularly with re-alignment of your forms after you remove your hull. With an external strongback, you will presumably have to re-attach your form supports on the hull side of your forms, which would mean starting the alignment process more or less from scratch.

If any of this is still confusing, let me know. Good luck with your project.

Allan Edie

Messages In This Thread

Strip: Cut off and re-glued tops of forms
aikijay -- 5/20/2014, 7:25 am
Re: Strip: Cut off and re-glued tops of forms
JohnAbercrombie -- 5/20/2014, 11:34 am
Re: Strip: Cut off and re-glued tops of forms
aikijay -- 5/20/2014, 6:25 pm
Re: Strip: Cut off and re-glued tops of forms
JohnAbercrombie -- 5/20/2014, 7:10 pm
Re: Strip: Cut off and re-glued tops of forms
Kevin Greer -- 5/20/2014, 4:41 pm
Re: Strip: Cut off and re-glued tops of forms
aikijay -- 5/20/2014, 6:29 pm
Re: Strip: Cut off and re-glued tops of forms
Kevin Greer -- 5/20/2014, 8:09 pm
Re: Strip: Cut off and re-glued tops of forms
howard -- 5/21/2014, 12:30 am
Re: Strip: Cut off and re-glued tops of forms
aikijay -- 5/21/2014, 5:31 am
Re: Strip: Cut off and re-glued tops of forms
A. Edie -- 5/21/2014, 12:31 am
Re: Strip: Cut off and re-glued tops of forms
aikijay -- 5/21/2014, 5:56 am
Re: Strip: Cut off and re-glued tops of forms
A. Edie -- 5/21/2014, 12:34 pm
Re: Strip: Cut off and re-glued tops of forms *PIC*
JohnAbercrombie -- 5/21/2014, 1:51 pm
Re: Strip: Cut off and re-glued tops of forms
A. Edie -- 5/21/2014, 11:40 pm
Re: Strip: Cut off and re-glued tops of forms
JohnAbercrombie -- 5/22/2014, 10:50 am
Re: Strip: Cut off and re-glued tops of forms
A. Edie -- 5/22/2014, 11:42 am
Re: Strip: Cut off and re-glued tops of forms
Bill Hamm -- 5/23/2014, 4:37 pm
Re: Strip: Cut off and re-glued tops of forms
JohnAbercrombie -- 5/21/2014, 1:57 pm