Hi Guys,

I was wondering what you have come up with for holding wing halfs together while the epoxy in the center section dries. I have stretched rubber bands from wingtip to wingtip, but if there is some dihedral that doesn't seem to give equal pressure. I have used long pieces of masking tape to give good holding power while the glue sets. That makes it difficult to keep the center section exposed and wipe off excess epoxy while it sets though.

Thanks for any ideas!

Ernie

I am not a pro at this, but after a few kits I have come to rely on the following approach which seems to work for ARFs as well as full kits.
(1) Lay a band of masking tape (I use the light tack stuff) right up against the edge of the wing root rib all the way around, top and bottom.
(2) Slather on your epoxy and use high tack masking tape to snug the wing halves together.

The band of tape handles the ooze and eliminates virtually all the cleanup.

Hi Ernie, first of all, do a trial fitting of the wings with the dihedral brace inserted. The root ribs must be sanded flat with a bar preferably longer than the chord. The brace should fit snugly, and light sanding of the edges of the brace or pockets may be necessary. There should not be any gaps between the root ribs when you join the wings. Precut a number of 1" width masking tape (8" to 10" long). I use the normal paper type. When you epoxy (60 min epoxy will let you work at a relaxed pace and is much stronger), fill the brace pockets with epoxy, and apply epoxy to both sides of ribs and brace. Put them all together and apply just enough pressure to close the gap between the ribs. Use a rag dampened with alcohol to wipe off any epoxy squeeze out. While you press the wings together, it will be easier to get someone to apply the masking tapes on the top and bottom of the wings, in a length-wise direction. You can put them 2-3" apart. The tapes will keep the root ribs from separating. Lay the wings on a table with some foam support near the tips until the epoxy cures. You can also lay the wings vertically against a wall with chairs etc around it to prevent it from falling down should there be a gust of wind. The idea is to reduce any bending stress at the wing joint while the epoxy cures. Meanwhile wipe off anymore epoxy ooze. When the epoxy cures, remove the masking tapes. peel them off in a direction that will not lift the balsa grains off the sheeting. You can swab alcohol on the sticky side of the tape to facilitate the removal. That's it ! Hope this helps..............

How about if we combine Intruder and Rajul's methods. I like Rajul's idea about putting bands of tape right up to the root rib on both sides...... but wouldn't that leave a raised line of dried epoxy right where the two tape band come together in the center?

Thanks for the great input guys!

Ernie

Hi ernie, the masking tape is applied lengthwise, not chordwise. there's not much holding power chordwise as the dihedral angle tend to automatically peel off a short length of the tape near the root. That's why you need about 8-10" perpendicular to the wing joint line.

Glue the dihedral brace into one wing and let it set up.

Test fit the wings together and sand the other side of the dihedral brace as necessary to allow the root ribs to make good contact, front to back and top to bottom.

Put the tape chordwise next to the joint as suggested above, to keep the ooze off the surface of the wings.

Lather up the dihedral brace and pocket (but not the root ribs) with 30 minute epoxy and slip the wings together and pull them apart a couple times to distribute the epoxy in the dihedral brace pocket.

NOW, put five minute epoxy on one root rib and slide the wings together.

Hold them in position with your hands until the 5 minute epoxy sets (about 2-3 minutes).

Set the wing aside until the 30 minute epoxy on the dihedral brace finishes setting.

Remove the protective tape.

Jim

Hi Rajul,

I understand that in your description the masking tape is applied span wise to hold pressure on things. However, Intruder is suggesting putting some chordwise to protect the center section from the oozing epoxy. I said why not do both?

Thanks for the input also Jim. You guys are GREAT. I don't seem to use much 5 minute expoxy these days, just personal preference I guess. Sure would make a quick job of holding things together though!

Ernie

Sig has a good way to do this. Once epoxy is applied stand wing up in a corner and put some weights on the top. Do a dry fit first and check that dihedral is correct. Make sure the wing is in a area that won't get bump

I use a method very similar to JRF's.


Mike

on my Ryan STA_M I had the nylon bolts thru the holes and the wood dowels in the fronts and used rubberbands from dowel to dowel and rubber bands on top of wing around the wing bolts and around the wing bolts on the bottom. Much better than tape and it pulled them together real nice.

Same as flyinrain...the Sig method. Worked well on my Extra 300XS. Of course, it helps to have flat wing tips! I used a thick Websters......

I use 5-minute epoxy and just press the halves together and hold it with my hands on the wingtips until it dries.