IMAC Aero Tech 35% Velox Custom Build

[BalsaDust]

Is it done yet???

 

[Snoopy1]

I was wondering what technique you were planning on using to sheet the foam.

I'm dying to try vacuum bagging, but I have better things to spend my money on than a pump.

What I can say is that when I bought the ViperST I was committed to styrofoam wings. I decided to go the vacuum way. Yes it is quite expensive and you need to really learn a new way of doing things. After it is all said and done it does make one very smooth, flat and perfect aero foil, and it is stiff but is heavier than a buildt up wing. Personally looking back if I had the choice I think I would prefer to build a built up wing. And Now I have an expensive vacuum system taking up floor space in my workshop and do not know when it will be used again. I only wish I had a bunch of building friends close enough to use it and make use of it.

 

[stangflyer]

@stangflyer

The overall construction is foam core so this may take a while as I will be doing it all old school like my Lanier Extra and my two Ohio RC Giles I built years ago
What do you mean by old school. Are you going to make the wing out of balsa, or how.

I was wondering what technique you were planning on using to sheet the foam.

I'm dying to try vacuum bagging, but I have better things to spend my money on than a pump.

To answer both questions... old school to me is make up my wing skins for each side of the wings, stabs and fin/rudder. I will then glue them into place with the cores in their perspective shells laden with equal heavy pressure covering the entire cores. Like you Doug, I just can't justify purchasing a pump and all the accessories to build one foam core plane. The three previous foam core planes I built came out beautiful and flew amazing. There are many people like Terry Wiles, Joe Mitchell and Randy Hinton that are far ahead of the game, (and me for that matter) that I totally get why they use them. I just don't build enough let alone foam core to make it worth the expenditures.

Here are a couple of photos of the foam core planes I built a number of years back. No vacuum system.

Ok, one. I can't seem to find my photos of the rest. Maybe on my other desktop pc? You've all seen my Lanier Extra. At any rate, this is my old school way.

 

[dhal22]

Gorilla glue means no vacuum system is needed. Roll gorilla glue or any poly glue on the foam with a foam paint roller and roll it until ONLY a sheen is visible, mist your skins with water and assemble everything in the foam shucks. I clamp the assemblages between pieces of 3/4" MDF and let the glue dry. This is one area where poly glue has no equal as it bonds foam and balsa with amazing strength.
Do a sample test and you will see how deep the glue expands into the foam.

 

[stangflyer]

Gorilla glue means no vacuum system is needed. Roll gorilla glue or any poly glue on the foam with a foam paint roller and roll it until ONLY a sheen is visible, mist your skins with water and assemble everything in the foam shucks. I clamp the assemblages between pieces of 3/4" MDF and let the glue dry. This is one area where poly glue has no equal as it bonds foam and balsa with amazing strength.
Do a sample test and you will see how deep the glue expands into the foam.

Yup, that's pretty much how I did the previous three. Except way back then not many people were using Gorilla glue. Most everyone including myself used the construction grade Elmers. But I'm going to change it up on this one. Please keep tabs on me. I may need suggestions from you fellas.

 

[Alky6]

I borrowed a vacuum system from @imacfanatic to do my JTEC build. I will never look back. It was so easy to do and was the part I was most afraid. Of course I haven’t bought one yet, but I know where it resides... . Looking to do a 2m pattern plane in the near future.

 

[49dimes]

To answer both questions... old school to me is make up my wing skins for each side of the wings, stabs and fin/rudder. I will then glue them into place with the cores in their perspective shells laden with equal heavy pressure covering the entire cores. Like you Doug, I just can't justify purchasing a pump and all the accessories to build one foam core plane. The three previous foam core planes I built came out beautiful and flew amazing. There are many people like Terry Wiles, Joe Mitchell and Randy Hinton that are far ahead of the game, (and me for that matter) that I totally get why they use them. I just don't build enough let alone foam core to make it worth the expenditures.

Here are a couple of photos of the foam core planes I built a number of years back. No vacuum system.
View attachment 100865
Ok, one. I can't seem to find my photos of the rest. Maybe on my other desktop pc? You've all seen my Lanier Extra. At any rate, this is my old school way.

When I did my Godfrey Extra the cores for the wings were hot wire cut and the remaining halves (shell) used to hold the sheeting down as the glue dried. As I recall.... used a 3/4" cut sheet of plywood with two 25lb bar bell weights on top of it all. Elmers wood glue did the job for me. Thinking back the hardest part was not burning up or melting the foam with the wire cutter and a car battery or burning the wire filament in two.

BZ to you though for tackling such a project. I found it to be such a chore. Much rather glue sticks together and better yet I much rather pull a finished model from a box. As a kid I got more glue on my hands and the model itself when doing the plastic kits. Now engines! that's a different story.

 

[stangflyer]

When I did my Godfrey Extra the cores for the wings were hot wire cut and the remaining halves (shell) used to hold the sheeting down as the glue dried. As I recall.... used a 3/4" cut sheet of plywood with two 25lb bar bell weights on top of it all. Elmers wood glue did the job for me. Thinking back the hardest part was not burning up or melting the foam with the wire cutter and a car battery or burning the wire filament in two.

BZ to you though for tackling such a project. I found it to be such a chore. Much rather glue sticks together and better yet I much rather pull a finished model from a box. As a kid I got more glue on my hands and the model itself when doing the plastic kits. Now engines! that's a different story.

Right? I was the same way. All my mother had to do is look at my hands, clothes, face, hair... (yes I had sum when a kid I was)....and she knew I was playing with glue again.

 

[stangflyer]

Okay gents, it looks like I'm going to have 4 days off during the Christmas break. Which means that I should be able to get a little bit done on this build. I have been mulling around in my head a few ideas before I even get started and thought maybe I would pose the question to a a few of you experienced builders. I know that Terry Wiles and quite a number of other gentlemen do this, however I'm curious as to the real benefit of it. What I am talking about is cutting lightning holes in the flight surfaces such as the wings stabs fin and rudder. I think it looks cool but I'm wondering if the weight savings is negligible enough that it's even really worth doing it. What do you guys think? Kelly, Doug, anyone else that has had experience building foam core planes? Is the weight Savings of cutting lightning holes in the surfaces really worth the extra effort?

 

[stangflyer]

I borrowed a vacuum system from @imacfanatic to do my JTEC build. I will never look back. It was so easy to do and was the part I was most afraid. Of course I haven’t bought one yet, but I know where it resides... . Looking to do a 2m pattern plane in the near future.

Wish I knew someone close that has one. Alas, not many true builders left here in Boise. Pretty much zilch for foam builds. Unless it comes from Hobby King or the like and is BNF, they would look at me as though I'm crazy.