Ok, I just got an almost complete kit for a Sig Senior, but all the wing is missing. I do have a pattern for the ribs but no access to a bandsaw or scroll saw. What would everyone recomend to cut these ribs out straight and level? And the best method to transfer pattern to sheet. This is all new to me.... after all beginers forum, right. Thank you for your time.

It is great that you are willing to scratch build the wing! I've been using a hand coping saw on my last few projects as my electric saw is in the USA. I glue 4 rectangular pieces of balsa (at a time) together only on the edges, use a pin to transfer the rib pattern to the top one, ball point pen the pattern, and then carefully cut it out and sand to shape. I have a few sanding blocks that are quite small for the spars and turb spars. It works out okay. I am sure you will get lots of advice here, but it can be done. All it really takes is motivation and patience. Put the rib stack together when you have them all cut out and sand to make them all the same shape. Best of luck to you! The Senior Kadet is a great flying plane and you will learn a lot as you build it.

Make one rib out of something hard and use it as a guide to cut out all the ribs with a knife or razor blade. Aluminum is ideal, but hard plywood will work, too.

You can order the wing kit from Sig, should fit the ARF ok.

The balsa wing kit from SIG is:

<br type=''_moz''/><table bgcolor=''#20548a'' border=''0'' cellpadding=''2'' cellspacing=''1'' width=''605''><tr><td bgcolor=''#ffffff'' valign=''top''><font color=''#414141'' face=''Verdana'' size=''1''>SIGRPBK258<input name=''dp_prod4'' value=''SIGRPBK258'' type=''hidden''/></font></td><td bgcolor=''#ffffff'' valign=''top''><font color=''#414141'' face=''Verdana'' size=''1''>BALSA WING KIT- KADET SENIOR<input name=''dp_desc4'' value=''BALSA WING KIT- KADET SENIOR'' type=''hidden''/></font></td><td align=''left'' bgcolor=''#ffffff'' valign=''top''><font color=''#414141'' face=''Verdana'' size=''1''> EACH<input name=''dp_um4'' value=''EACH'' type=''hidden''/></font></td><td colspan=''2'' align=''right'' bgcolor=''#ffffff'' valign=''top''><font color=''#414141'' face=''Verdana'' size=''1''>$36.99</font></td></tr></table>

Im sitting at work thinking, what if I could find a piece of aluminum, or sheet metal and trace the rib on two peices of metal. I would cut them both together so they would be a match. Make kind of like a balsa sandwich with the metal on outside, rough cut and then sand. Would that keep everything straight and level? What do you guys think? Thanks

You can do that.. just remember to cut the balsa with very sharp... brand new... #11 exacto blades, then sand the edges square and smooth.

Does this wing have all the same size ribs?

CGr.

I think there are 10 the same, then 4 the same, then 2 the same I believe.. it that makes any sense.. lol. SIGSenior somebody please correct me if I am wrong.

Yep. Aluminum is fancy. Some plans have you make a plywood inner and outer former and then bolt them together with the basla ribs between. This works even <u>better</u> with tapared wings as then the taper is pre-evened up. You want to make the "masters" 1/16" oversize to allow for final sanding once the ribs areglued up to the spars.

You don't even need patterns, just mark the profile on the outer twoand sand away.

Check these articles out:

http://www.airfieldmodels.com/inform...ribs/index.htm

http://www.airfieldmodels.com/inform...ribs/index.htm

http://www.airfieldmodels.com/inform...tion/index.htm

I usually trace the rib from the plan onto thin, white paper. Cut that out and use it to make a template out of plywood. Then I use the plywood template to cut out the ribs. That's for a constant-chord wing. Your ribs will all be identical, except for a few that may have additional cutouts or may have a differing thickness of material. Check the plans. The differences are usually not critical, unless one or two ribs have to be made of plywood. If you are careful, you can cut out plywood ribs with a coping saw and then sand to final contour.

You can make an entire airplane out of hand tools if you desire. Power tools only make it easier and faster to mess things up (or do them well-you pick!)

Ok, I read in one of those article you posted (thank you by the way) that there is a shallow notch on the spar for shear web. What method would be used to create this notch and keep it straight? Thanks.

You are welcome; check this:

http://www.rcuniverse.com/forum/fb.asp?m=8154038

Cutting a notch in the spar to accept the shear webbing results in a tremendously strong "I-beam" stucture for the wing. The best way to do it would be to use a router table with a 1/16, 3/32, or 1/8 bit and route the notch into the spars. Unfortunately, most of us don't have such a setup. I tried it with a Dremel tool and Dremel router table, and the results were marginal. I've also used a radial arm/table saw to rip the notch; again, this works if you have a saw and a narrow kerf blade.

It's also, for the most part, unnecessary. If you were flying a 3D ship, you might need the added strength. You'll be fine if all you do is glue the ribs to the bottom spar, cut the shear webs to the distance between the spars, glue in the webbing, then glue the top spar to the top of the webbing. Most wings are built in this fashion. You can even build the wing, then glue the webbing to the back/front of the spars. On a Kadet Senior, any of these methods will give you the necessary shear resistance.