Model IV two part doors

[henrysamson]

I have a model IV with the two part doors. Actually three parts. Polycarbonate top and aluminum bottom with a fiberglass strip between and overlapping both.

The instructions do state that the fiberglass strip is riveted with the metal to the lower of the two center tubes but it does not mention riveting the polycarbonate except at the top and the sides. What have others done? Seems that the bottom of the window and the top of the fiberglass strip will be pretty loose.

The instructions state 1/4 x 1/8 aluminum pop rivets for the metal to tube and 1/4 x 1/4 for the fiberglass and metal to tube where they overlap but no mention of rivet size for the polycarb to tube. It is close in thickness to the fiberglass and aluminum together so I am thinking 1/4 x 1/4.

Thanks!

Henry

[t j]

The fiberglass center strip rivets are 1/8 X 1/4 AL. Rivet to both horizontal center tubes of the door, top and bottom of the center piece. the polycarbonate top and the aluminum bottom skins go under the fiberglass center strip and overlap a center tube frame so the rivets capture the bottom of the polycarbonate and the top of the aluminum skins.

All around the perimiter of the frame use 1/8 X 1/8 AL.

[N82HB]

I would suggest replacing bottom aluminum with polycarb. It increases you enjoyment a lot! I have had them both ways.

[henrysamson]

Thanks Tom!

I got everything clecoed together this morning with just the rivets through the fiberglass on the lower cross bar. Seemed obvious that something had to done to the top one to make it lay flat. Your post reinforced what I was thinking so I drilled and clecoed the top. Looks good! Thanks for the rivet sizes.

I never liked the look of the full doors. Just my personal preference so I'll see how it goes. I have been working on this for too many years and right now I'm just focussed on getting it done!

But I am curious though. Are you suggesting the one piece bubble doors or just a polycarb panel on the bottom with fiberglass in between?

Henry

[N82HB]

Just replace bottom with poly.
You can see mine in my photo albums.

[henrysamson]

Wow, they look REALLY nice. Much better than the bubble doors in my opinion. I may do this. It looks like you kept a border of aluminum around the bottom and sides of the poly carb on the bottom window. Is that correct? If so I can just cut my metal skins out leaving a couple of inches all around.

I put in an LP Aeroplastic windshield. So, I still have the Skystar provided windshield plastic. I'm hoping it is the same thickness as the side windows.

[t j]

Henry, On my 1994 kit the windshield is .090" and the door windows are .060" Lexan. That's almost exactly the same as 3/32 and 1/16 thickness. You will want the thinner stuff on the doors.

[N82HB]

The framework you see is just paint.
I think it is very nice. I am good friends with the builder of my airplane and I always compliment his work. I wish I were so smart.

I am a displaced Texan as I grew up in Denton. I am sure we'll be friends.
K

[henrysamson]

You're right, the windshield polycarbonate I have is thicker.

I'm going to price some 0.06 today.

Still not sure which route to go as I made my own seat cushions including matching pieces for the doors. Here is a picture of one of them. I know I may not be able to fly with the doors open with them installed and in place (they velcro to the tubes). Decisions, decisions.