Spar Dimensions

A forum about all aspects of the construction and maintenance of the original Hatz CB-1 biplane. Here is the place to ask your questions and get the answers from the real experts.
danjquinn
Posts: 10
Joined: Fri Dec 14, 2012 10:50 am

Spar Dimensions

Post by danjquinn »

I need help with the spar dimensions. I have looked in the previous newsletters and on this forum with no luck. I assume I am missing this information in my set of plans and would like to have the correct dimensions before I butcher up a spar. Is there a correct angle to bevel the spars? I have been playing with autocad and using what info I have been able to get from my plans. I have 82 degrees on the top but it appears the bottom of the spars may have a slight bevel. Also is there a correct dimension for the height? I have 4.775 in. for the front of the spar and 4.885 for the rear. I print that out to scale and it is a close fit in the rib. I appreciate any input.
Thanks
Dan
ha622
Posts: 14
Joined: Thu Jan 13, 2011 1:55 pm

Re: Spar Dimensions

Post by ha622 »

You may want to take a look at the thread "Rib dimension discrepency" in the Hatz classic forum

Juerg
Juerg Mueller, Switzerland
Hatz SN-622
danjquinn
Posts: 10
Joined: Fri Dec 14, 2012 10:50 am

Re: Spar Dimensions

Post by danjquinn »

ok that helps. My ribs are right on for the 25" center to center dimension but they are about .025" taller in the spar opening. I assume I will have to bevel the spars to the 4.900 dimension or maybe even a few thousands bigger and fit each rib to be a snug fit ? If I have to remove a slight amount of wood from the ribs to fit is it better to remove from the top of the opening or bottom, or does it matter.
dan
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