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Hatch spars

PostPosted: Wed Apr 11, 2012 11:15 am
by Forrest747
I did look it up to see how many spars or ribs do people put in thier hatch.
I have seen 3 inner spars and some even have done 4, but i did 2 at about 20 inches from teh outside spars. I put some cross braces and plan on skinning it with 1/4 baltic birch. the hatch dimensions are 61.5 inches wide by 48" in height. In your opinion am i good enough or do i need to add a few more. I ripped 2x4 into 1 1/4 widths to form the inner spars.

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Re: Hatch spars

PostPosted: Wed Apr 11, 2012 12:37 pm
by Woodbutcher
You should be fine, as long as you do some cross supports as well. I usually have about 10-12"s between spars. The 1/4" will firm the hatch up nicely. Your hatch looks flat to there will be no stress on the plywood as there would be on a curved hatch. Good luck!

Re: Hatch spars

PostPosted: Wed Apr 11, 2012 12:42 pm
by Forrest747
Yes its a flat hatch and the software says it should be fine, with the weak spots in the large openings. i added some horizontal to those spots and the computer liked it much better. So i will add those and then some diagonal from near the hinge points. thinking of adding two more hinges just to be safe teh stress levels in teh computer were a little higher than i would of liked.

Re: Hatch spars

PostPosted: Wed Apr 11, 2012 4:00 pm
by planovet
I would have put them closer together but I tend to overbuild :lol:

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