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Re: Box Beam Approach Idea
By:Mike Allen
Date: 6/1/1999, 4:36 pm
In Response To: Box Beam Advice? (Lars Durban)

Obviously all the ideas previously stated have all worked and will give you a good result. But here are a few of my thoughts:

1/ The internal armature approach used by Nick is, I believe, a revolution in simplicity in constructing a strip kayak. When he came up with that idea, kayak building became accessible to a whole new range of people with lesser building skills.

2/ Any stiff member (easy now!) can be used as an armature, the only technical difficulty is attaching and aligning the forms.

3/ I am convinced it is more simple to not use the armature to align the forms, but to drill 2 sets of aligned 1/2" holes thru all the forms and to line them up using string lines. You are then free of the individual wiggles and wonks of the strongback and can very easily line up each form to a string width ( in my case 1/32"). I repeat easy. Easy to see. Easy to see from 5 feet away. Easy to see every time you get in the basement. Easy to see if you give up for 2 months for the summer and come back in the fall.

4/ In order for quick and simple form alignment, I use wedges - no nails or screws or pins thru the forms. This is how:

Assuming 12" placement w/ 1/2" forms, I put 2 spacers (10 1/2" long) on each side of the strongback. One end is cut orthogonally and the other is cut at an angle. I cut the forms very sloppy - 3/16" gap all around. I put on the end form. Then attach a spacer, slide on the next form, attach a spacer until they are all on. Then attach the other end forms. The most outward forms (say 3 and 15 - but this could vary) are rigidly attache in any way you want, but align them horizontally by clamping a strip on a horizontal reference line on each form and sight them straight ( takes 15 minutes). Then thread a string thru all the holes and tie to forms 3 & 15 ( drill 3/64" holes here). Then at each station, hand push a wedge (on ea side) between the spacer and the form, line up with the string and drive in the wedges - the form won't move. Repeat for all the forms. Go back and adjust any you don't like - it just takes a few taps of the hammer on the wedge to slightly loosen, then tap the form, then redrive the wedges ( duh, simple huh?) (This takes maybe 30 minutes). Now this is real accurate. More accurate the wider you space the string line of course, but my spacing is about 6" and I gotta laugh at how easy it is.

Now I am a slow builder and don't have much free time, and the humidity conditions are fairly constant as I'm building indoors, but there has been no form creep as I can yet see ( 1 month), and I guess the effective strongback width (therefore stiffness) has been increased by the width of the spacers, but maybe someone else would use screws or pins for the wedges or forms but I just like the idea of wedges alone.

In summary - all the other methods are great, but here is another idea.

- mick

Messages In This Thread

Box Beam Advice?
Lars Durban -- 5/31/1999, 6:10 pm
Re: Box Beam Approach Idea
Mike Allen -- 6/1/1999, 4:36 pm
Re: Box Beam Approach Idea
phillip kearney -- 6/2/1999, 4:30 am
Re: Box Beam Approach Idea
Mike Allen -- 6/2/1999, 12:55 pm
Re: Box Beam Fundamental Idea
Mike Allen -- 6/2/1999, 1:17 pm
A picture would be worth a 1000 words...
Ross Leidy -- 6/2/1999, 2:32 pm
Re: A picture would be worth a 1000 words...
Mike Allen -- 6/2/1999, 3:06 pm
Re: Box Beam Advice?
Nick Schade - Guillemot Kayaks -- 6/1/1999, 1:40 pm
Re: Box Beam Advice?
Hank Vanderaa -- 6/1/1999, 11:14 am
Re: Box Beam Advice?
Pete Rudie -- 6/1/1999, 12:40 am
Re: Box Beam Advice?
AL BRATTON -- 5/31/1999, 9:30 pm
Re: Box Beam Advice?
AL BRATTON -- 6/3/1999, 10:23 am
Re: Box Beam Advice?
Kris Gabrielson -- 5/31/1999, 9:43 pm