IMAC First Carden 124" Extra 300 Pro Build

[scruffmeister]

I had originally planned to start with the motor box, but now decided to start with the stabs then wings followed by fuselage. Began by weighing all the sheeting supplied with the kit and grouping it for the various foam parts. Just waiting for the postman to bring a bottle of Titebond II and I'll get started on making the stab skins. Dennis at Carden pre-groups the wing sheeting (which requires hard density) which saved me a fair bit of work.

 

[kevinjulieevan]

looking forward to following this thread! one of these days i will tackle building a plane but currently i'm just watching build threads

 

[scruffmeister]

Thinking ahead a little bit, I'm going to have to make some servo boxes to glue in before I can skin the wings. I have settled on something like the one shown below which is a picture I found elsewhere on the Internet.

I've never had to make a giant scale servo box before so a couple of questions for experienced builders:

1) Is the above design a good one, or have you found better ones?

2) Will 1/8" Liteply be sufficient for the sides or do I need to use Birch ply? (I'll only be using this plane for IMAC).

3) I am intending to glue the box in with polyurethane glue, anything I should watch out for beyond excessive foaming?

Thanks!

 

[Kevin-Young]

1) Yeah, that picture of the servo box will be just fine. There are a lot of different ways of doing it so you will get a ton of different opinions.
2) liteply will be fine
3) polyurethane glue works really well because it is sandable.

 

[scruffmeister]

Titebond II arrived, so I taped up the skin for the horizontal stabs. Using a small injector bottle I glued a single edge just to get a feel for what was involved - so, thin bead of glue, closed the joint, wiped the glue away with a putty knife and then sanded over the joint to try and get balsa dust to fill the smaller cracks. Finally, weighted it down and it's drying.

So, this is all good, but there are another 50+ edges to glue - so what's the secret to doing an entire skin in one go? Currently I've just got visions of glue going everywhere and ending up with a buckled skin!!

 

[Notorious B.E.N.]

I go to Tractor Supply or another small farm/ranch supply place and buy needles with syringes. You can also get syringes from pharmacies but I don't know what gauge of needles they carry since humans typically need smaller sizes.

 

[Alky6]

If you are vacuum bagging you don't need to edge glue. The vacuum will pull some epoxy into the joint. Just trim your edges so the fit right and tape them together to hold them in place. Super easy! I would have died if I had to edge glue every piece on my jtec.

 

[scruffmeister]

I am vacuum bagging, but was planning to edge glue too. @Terryscustom what're your thoughts on this as in your video (which is essentially my "manual"!) shows tape on the sheeting but I can't tell if is edge glued at 09:53?

 

[BalsaDust]

I do not believe terry edge glues his. If I remember correctly going the vacuum bag route it basically sucks the glue into the joints.

 

[orthobird]

Hello Scruffmesiter, awesome thread.
Wanted to give you some information, and I would like to first clarify that I am not trying to debate against anyone or try to persuade you one way or the other, just want to share with you some information, that can help you in making a decision as to what to do first, and it all depends on how you want to do things.

For example, one consideration is to build the fuselage frame and motorbox, but not glue on the turtle deck or any of the foam parts (belly pan, etc...), then make the wings and stabs.

Reason being, is, that once you have the fuselage sides up, you can then assure that the root of the stabs and wings sit flush with the fuselage sides. there are also other reasons, such as, how will you set the incidence, etc... but this depends on what system you will use to fix the wing root to the fuselage sides.

Just food for thought.


Best regards


Cam