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#1 mr.incredible Feb 17, 2012 11:27 PM

Foamy Fuselage
 
17 Attachment(s)
This is a fantasy foam fighter fuselage scaled up from Jarel's original open source design. I will post both his design and my scaled up version.

I need something to help me with orientation. I want something I can eventually adapt to an FPV camera. I want to mount the camera in the cockpit with a little bit of nose showing in the camera view. I have found a couple designs that I could probably adapt but then the other day, I found Jarel's post for his really nifty design. http://www.rcgroups.com/forums/showthread.php?t=1595253

Here is what I have so far. This is my first attempt at working with foam. I love it. Specially since I took the advice of a few other people and got the foam core board from Dollar Tree. "Everything is a Dollar" 20x30inch foam core board for $1.00. Cant beat it. Soak it in alcohol for about a min and the paper comes right off. It is 5mm thick but since I scaled it up by about 250% over the original pattern it worked out well.

Jarel's original is scaled for a MQX which is a small quad copter. My tricopter is quite a bit bigger the arm size is 10 inches center to motor, and the center frame is about 6 inches in diameter. I don't know that the actual scale turned out to be but it is roughly 250% bigger.

As I have stated, this is my first go using foam as a medium. I am learning as I go. I really like it and I will most definitely be using it again. I have the model mostly finished in roughing it out. Now I have to learn how to fill gaps and then prime and paint.

Update: I just stumbled upon something this morning for filling gaps in foam. More foam! Gorilla Glue Precision glue pen, Dries 2X faster.

I tested on a scrap couple of pieces. Just takes a little bit in the crack, wet it and wait. It will start foaming right away. I did mine about 4 hours ago and it is ready to be worked.

Update - Painted: Through much trial and error (lot of error) here are my results. The Gorilla Glue does work well but it still leaves a lot of filling to do. It bubbles up a lot whether you wet it or not. It creates bubbles that have to be filled. For big gaps it worked well.

From the Painting forum I found that a thinned spackle compound fills the bubbles and seams, it also helps to cover the foam grain from the ends. After filling and sanding when you get the form the way you like it, airbrush spray with Polycrylic. It's a water based polyurethane clear coat.

I spent a lot of time filling and sanding. I got things pretty smooth. Then I proceeded to screw it up with paint. As I usually do when painting, I did not exercise patience. I did not wait long enough to mask and spray the cockpit. My tape pulled off paint here and there. I did not keep any of the grey paint, thinking I was almost through. Of course dried the color is different from wet, so it is next to impossible to mix a new batch. I ended up having to re-paint and re-mask. I decided to not worry too much about making it perfect this time. I will most likely crash it on multiple occasions.

#2 Vantasstic Mar 04, 2012 10:11 AM

Nicely done. It sure gives a tricopter a totally different look. I might have to try your plans myself...looks really cool!!!

#3 Markusab Mar 04, 2012 10:12 AM

Quote:

Originally Posted by mr.incredible (Post 20780817)
This is a fantasy foam fighter fuselage scaled up from Jarel's original open source design. I will post both his design and my scaled up version.

I need something to help me with orientation. I want something I can eventually adapt to an FPV camera. I want to mount the camera in the cockpit with a little bit of nose showing in the camera view. I have found a couple designs that I could probably adapt but then the other day, I found Jarel's post for his really nifty design. http://www.rcgroups.com/forums/showthread.php?t=1595253

Here is what I have so far. This is my first attempt at working with foam. I love it. Specially since I took the advice of a few other people and got the foam core board from Dollar Tree. "Everything is a Dollar" 20x30inch foam core board for $1.00. Cant beat it. Soak it in alcohol for about a min and the paper comes right off. It is 5mm thick but since I scaled it up by about 250% over the original pattern it worked out well.

Jarel's original is scaled for a MQX which is a small quad copter. My tricopter is quite a bit bigger the arm size is 10 inches center to motor, and the center frame is about 6 inches in diameter. I don't know that the actual scale turned out to be but it is roughly 250% bigger.

As I have stated, this is my first go using foam as a medium. I am learning as I go. I really like it and I will most definitely be using it again. I have the model mostly finished in roughing it out. Now I have to learn how to fill gaps and then prime and paint.

Update: I just stumbled upon something this morning for filling gaps in foam. More foam! Gorilla Glue Precision glue pen, Dries 2X faster.

I tested on a scrap couple of pieces. Just takes a little bit in the crack, wet it and wait. It will start foaming right away. I did mine about 4 hours ago and it is ready to be worked.

Update - Painted: Through much trial and error (lot of error) here are my results. The Gorilla Glue does work well but it still leaves a lot of filling to do. It bubbles up a lot whether you wet it or not. It creates bubbles that have to be filled. For big gaps it worked well.

From the Painting forum I found that a thinned spackle compound fills the bubbles and seams, it also helps to cover the foam grain from the ends. After filling and sanding when you get the form the way you like it, airbrush spray with Polycrylic. It's a water based polyurethane clear coat.

I spent a lot of time filling and sanding. I got things pretty smooth. Then I proceeded to screw it up with paint. As I usually do when painting, I did not exercise patience. I did not wait long enough to mask and spray the cockpit. My tape pulled off paint here and there. I did not keep any of the grey paint, thinking I was almost through. Of course dried the color is different from wet, so it is next to impossible to mix a new batch. I ended up having to re-paint and re-mask. I decided to not worry too much about making it perfect this time. I will most likely crash it on multiple occasions.

BRAVO!!!!!! Nice work!:popcorn::popcorn::popcorn:

#4 Vantasstic Mar 04, 2012 10:21 AM

Not to detract from the foamy fuse...but what tricopter frame are you using. It looks like the whole tail shaft swivels for yaw. I'd love to see how you've got that set up.

#5 mr.incredible Apr 01, 2012 09:25 AM

Quote:

Originally Posted by Vantasstic (Post 20933992)
Not to detract from the foamy fuse...but what tricopter frame are you using. It looks like the whole tail shaft swivels for yaw. I'd love to see how you've got that set up.

Sorry, I haven't even been watching for replies to my own blog. I just read your post. Yes, the whole tail rotates. There is another post on my blog dealing with that. I think it flies a lot smoother than just rotating the motor. I also do not have to worry about making different booms if a crash breaks the boom or motor mount, they are all the same.

#6 Vantasstic Apr 01, 2012 11:10 AM

Quote:

Originally Posted by mr.incredible (Post 21204100)
Sorry, I haven't even been watching for replies to my own blog. I just read your post. Yes, the whole tail rotates. There is another post on my blog dealing with that. I think it flies a lot smoother than just rotating the motor. I also do not have to worry about making different booms if a crash breaks the boom or motor mount, they are all the same.

Nicely done, thank you. It seems the tri's work better for FPV as they don't change motor speed in order to yaw, thus seems a little more steady when yawing around...plus their lighter by only needing three motors. I like the idea of the full tilting tail shaft. I might have to really look into giving one a try.


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