Author Topic: Ribs  (Read 467 times)

Offline 914pete

Ribs
« on: May 15, 2019, 07:40:22 AM »
I'm building my rib jig and laid out the full length rib pattern I received from Leonard. The last 10" of the bottom cap strip on the plan towards the trailing edge curves up 3/16". Are the rib bottoms suppose to be flat full length? I'm assuming yes and this was just a printer issue but would like confirmation. Thanks.

Online leshoman

Re: Ribs
« Reply #1 on: May 15, 2019, 08:04:11 AM »
You are correct. Bottom is flag
Les Homan

Offline 914pete

Re: Ribs
« Reply #2 on: May 20, 2019, 10:29:06 AM »
Thanks Les. Rib #1 done. I'll at least cut out all the gussets for all the ribs first and then try to get one rib done per day. Is the general consensus to build all the ribs the same, assemble them to the spars and then build the ailerons?

Offline Kamcoman77

Re: Ribs
« Reply #3 on: May 20, 2019, 12:25:17 PM »
You can save a little work by remembering to cut smaller gussets (ahead of time) that go on the compression strut ribs and glue them on instead of using full-size gussets. Some of the lower gussets from the front spar to the rear spar are not as tall as the non-compression strut rib gussets. This will save you having to modify the gussets after they are glued. Also remember that the #7 ribs (inboard aileron support) and the #12 ribs (outboard aileron support) have plywood doublers. You would not put regular gussets there if you use the doublers.

Offline jrbirdman47

Re: Ribs
« Reply #4 on: May 20, 2019, 12:26:53 PM »
I would not. I think I saved a lot of time by building each rib for its intended position, since there are several different types of ribs. (I incorporated the Iron Designs "K" block system) Then when they were all done there was virtually nothing remaining to build, (rib wise), and the wing went together quickly. For instance, the two inboard ribs on each wing have additional vertical pieces at the forward spar and are cut out to accept the wing attach fittings. They are easy to make in the jig, but difficult to modify once on the wing. Outboard ribs don't need certain diagonals because you will be putting a hinge block in that area between them, so why put them in and then have to remove them. (Been there, it's not easy!) Just look at the plans and figure out what needs to be done to make the rib you are presently building into what it should be and it will be less work later. You'll find that only a few ribs are "normal". Have fun! It's the most satisfying/ frustrating thing you'l do.

Offline 914pete

Re: Ribs
« Reply #5 on: May 20, 2019, 01:02:42 PM »
That makes sense. I'll have to dig through the plans and decipher each rib layout. The plans call for 15/16"+ for the rear spar to slide through. I realized I made the space exactly 15/16" on the first rib. I adjusted the jig for a solid 1". Is 1" enough space?
I too purchased Iron Designs supp. plans. I'll have to compare both sets of plans to figure out specific rib design/function. Has anyone layed out and posted pics of each rib?

Offline jrbirdman47

Re: Ribs
« Reply #6 on: May 21, 2019, 02:36:42 PM »
I think 15/16" is enough. Too much and you can't really get a good glue joint on both sides. I found out that if the joint is really tight the glue is so slick that when you slide the rib into place it just goes right in place and has plenty of glue between the rib and spar anyway. using the Iron Designs plans (And the you tube videos as well!) makes it easy to figure out how to build each rib. Make sure all measurements are made from the same reference point, such as the rear spar when cutting the rib to length, etc, and and your ribs will turn out great.