Building the F117 and looking for some mods

[Burnhard]

My first EDF aircraft was a FT Viggen. It got me hooked on jets so I was looking for something new. I recently watched a video which touched about the history of the Skunks Works and the development of the F117.

After a bit of research I came across the plans from Matagami and also the build from CarolineTyler.

My plan is to create a version for a 70mm EDF and also to add retracts. Looking at the pictures from Matagami and Caroline there should be enough space to add these but lets see.

Plans are printed at a 110% and have been glued together over the past days. First step today I sorted the electronics and did a bit of cutting of the first few pieces. I only have one and a half full sheets of foam board left so have ordered some new one. When building a model, I usually keep the larger scrap pieces for the next model. Same here, the next few days I will be using the scrap pieces I have and see how far it will take me.

As an EDF I am using a 70mm, 2750 KV, 12 blade engine that will be running on 4S together with a 65A ESC.

 

[JustPlaneChris]

Awesome! I will be watching this one for sure. An F-117 of some size is on my "to do" list, and I just happened upon a great deal on an 80mm Freewing fan unit... Hmm...

Chris

 

[Burnhard]

Only little progress today. I am short two sheets of foamboard which will only arive next week. Did a bit of cutting today and also a short test of the EDF unit. Dusted off the workbench. Will cut the bottom part tomorrow and then start fitting things together.

 

[Burnhard]

Awesome! I will be watching this one for sure. An F-117 of some size is on my "to do" list, and I just happened upon a great deal on an 80mm Freewing fan unit... Hmm...

Chris

The bigger the better ;-) Might be a challenge on the bottom piece. The 110% version just pretty much exactly fits on an A1 sheet of foam board.

 

[Matagami Designs]

The bigger the better ;-) Might be a challenge on the bottom piece. The 110% version just pretty much exactly fits on an A1 sheet of foam board.

Yeah I though it barely fit at 100% You could always glue two sheets together if you wanted to scale things any larger.

 

[Burnhard]

Did a bit more cutting today. Bottom plate is done. Also did a bit of testfitting and everything seems to fit together quite nicely. I am out of foam board for now.

Also wondering where to use what sort of carbon fibre. I have a 5mm tube which I could fit well to the spar. The only thing is I only have that one tube and that would just enough for each side. Another option might be to put the tube across like in the build from Caroline and then add some flat carbon fibre stripes next to the spars (these are just a bit more flexible than the tube. Will decide once I have cut the wings.

 

[CarolineTyler]

My first EDF aircraft was a FT Viggen. It got me hooked on jets so I was looking for something new. I recently watched a video which touched about the history of the Skunks Works and the development of the F117.

After a bit of research I came across the plans from Matagami and also the build from CarolineTyler.

My plan is to create a version for a 70mm EDF and also to add retracts. Looking at the pictures from Matagami and Caroline there should be enough space to add these but lets see.

Plans are printed at a 110% and have been glued together over the past days. First step today I sorted the electronics and did a bit of cutting of the first few pieces. I only have one and a half full sheets of foam board left so have ordered some new one. When building a model, I usually keep the larger scrap pieces for the next model. Same here, the next few days I will be using the scrap pieces I have and see how far it will take me.

As an EDF I am using a 70mm, 2750 KV, 12 blade engine that will be running on 4S together with a 65A ESC.

Sadly my F-117 died on its maiden
Launch was fine, controllable, was up about 30m when, I think, I had a lost connection and it destroyed itself.
Even more annoying was that the video on the action can is corrupted.
Good luck with your build !!! 👍😀

 

[Burnhard]

Sadly my F-117 died on its maiden
Launch was fine, controllable, was up about 30m when, I think, I had a lost connection and it destroyed itself.
Even more annoying was that the video on the action can is corrupted.
Good luck with your build !!! 👍😀

That‘s pretty sad indeed. I guess it does not have much gliding capabilities. Happened to me with Viggen V2.0 but this one basically glides forever and landed like nothing ever happened.

Stupid question: is there a trick to join the lower part of the wing with the main fuselage or is it just plain hotglue in the joint?

 

[CarolineTyler]

That‘s pretty sad indeed. I guess it does not have much gliding capabilities. Happened to me with Viggen V2.0 but this one basically glides forever and landed like nothing ever happened.

Stupid question: is there a trick to join the lower part of the wing with the main fuselage or is it just plain hotglue in the joint?

I used the clear gorilla glue, gave me time to get it positioned right....and lots of blue painters tape

 

[Burnhard]

New foam board arrived today but the UPS man decided not to leave it at our apartment so will need to collect tomorrow. Will try to cut the wings and final pieces tomorrow.

Did a bit of research on the retracts. The original has the rear retracts pretty far up front, roughly where the CG seems to be on Matagamis original plans. Will do some drawings on the foam tomorrow but I fear that this will interfere with the front formers. There is ample of space in the back but retracts add approx 150g of weight which is a lot behind the CG. The single front retract is probably not enough to counterbalance.

Thought about adding orange leds into the exhaust for a nice light effect.

 

[Burnhard]

I used the clear gorilla glue, gave me time to get it positioned right....and lots of blue painters tape

Many thanks for the hint. Unfortunately I don’t have that and Amazon here does not have it either. I can go with hotglue, CA or some whiteglue (the whiteglue works great for glueing the paper surfaces of the foam but for the foam itself it seems less ideal). Will probably go with the blue tape and hot glue. The strength will hopefully come from the carbon fibre I plan to add.

 

[Burnhard]

Did the cutting of the missing parts today and did a bit of sketching where the retracts would need to go. On the rear retracts that interferes with the wing spars as well as the formers. Also the area where the wheels would sit is super tight. In addition, the flying field where I go to has a grass runway only and anything below 65mm diameter for wheels does not work. Does not seem to be worth the effort. Will give it another thought tomorrow but I fear the retracts are off the table.

 

[Monte.C]

Many thanks for the hint. Unfortunately I don’t have that and Amazon here does not have it either. I can go with hotglue, CA or some whiteglue (the whiteglue works great for glueing the paper surfaces of the foam but for the foam itself it seems less ideal). Will probably go with the blue tape and hot glue. The strength will hopefully come from the carbon fibre I plan to add.

Have you ever tried BSI Foam Cure? It's the only thing I used on my last plane.
https://www.amazon.com/dp/B00DT86A86/?tag=lstir-20.
Love this stuff.

 

[Monte.C]

Many thanks for the hint. Unfortunately I don’t have that and Amazon here does not have it either. I can go with hotglue, CA or some whiteglue (the whiteglue works great for glueing the paper surfaces of the foam but for the foam itself it seems less ideal). Will probably go with the blue tape and hot glue. The strength will hopefully come from the carbon fibre I plan to add.

I just checked on Amazon.de and Foam Cure or Foam Tac aren't there, but there are two adhesives I've seen on German or Russian or Eastern Europe plane videos, I think at least one of them is the same as the ones I've mentioned. Oh - NumaVig uses one or both.
No need to use epoxy on a paper plane! As long as the Foamboard around the joint will break well before the glue joint ever will, you've got a good glue.

 

[JustPlaneChris]

I found another glue made by Beacon (makers of Foam Tac) named "Foam & Poster Board Adhesive) and I found it at the Dollar Tree store! Yep, it's one freaking dollar. I haven't used the Foam Tac to have a comparison, but this stuff works great so far. It stays flexible, which is what we want for foam. I'm already on my 2nd bottle. Big spender, I am.

https://www.dollartree.com/beacon-foam-poster-board-adhesive-175oz-bottles/307640

Chris

 

[Monte.C]

I found another glue made by Beacon (makers of Foam Tac) named "Foam & Poster Board Adhesive) and I found it at the Dollar Tree store! Yep, it's one freaking dollar. I haven't used the Foam Tac to have a comparison, but this stuff works great so far. It stays flexible, which is what we want for foam. I'm already on my 2nd bottle. Big spender, I am.

https://www.dollartree.com/beacon-foam-poster-board-adhesive-175oz-bottles/307640

Chris

Fantastic. Don't forget you gotta pay the light bill! Can't build planes by candlelight.
Just for reference: I have Foam Tac and it's real good but really overpriced. I found Foam Cure by BSI and it's basically the same at only a fraction of the cost. I use it almost exclusively now. It works like a thin rubber cement but cures very solid. Very nice working time of a few minutes. (Just my speed.) Only thing is I was told - and I guess they're right - that Foam Tac remains flexible enough for foamboard control surface hinges (like we use hot glue for) so I save the last of the pricy stuff for that use only.

 

[Burnhard]

I just checked on Amazon.de and Foam Cure or Foam Tac aren't there, but there are two adhesives I've seen on German or Russian or Eastern Europe plane videos, I think at least one of them is the same as the ones I've mentioned. Oh - NumaVig uses one or both.
No need to use epoxy on a paper plane! As long as the Foamboard around the joint will break well before the glue joint ever will, you've got a good glue.

Darn! Smashed my Viggen 2.0 today! Will need to do another rebuild. At least this time I did not loose the whole aircraft.

Many thanks for the hint with the glue. I saw that some of the Beacon products are available but could not find the one for foam board. Lately I have glued a lot with white glue and that seems to work on foam as well. Will do some experimenting in the lab ;-)

 

[OliverW]

I found another glue made by Beacon (makers of Foam Tac) named "Foam & Poster Board Adhesive) and I found it at the Dollar Tree store! Yep, it's one freaking dollar. I haven't used the Foam Tac to have a comparison, but this stuff works great so far. It stays flexible, which is what we want for foam. I'm already on my 2nd bottle. Big spender, I am.

https://www.dollartree.com/beacon-foam-poster-board-adhesive-175oz-bottles/307640

Chris

I've been using that stuff as well. I'm 99% certain it's the same thing as foam tac but in a different bottle

 

[Monte.C]

I found another glue made by Beacon (makers of Foam Tac) named "Foam & Poster Board Adhesive) and I found it at the Dollar Tree store! Yep, it's one freaking dollar. I haven't used the Foam Tac to have a comparison, but this stuff works great so far. It stays flexible, which is what we want for foam. I'm already on my 2nd bottle. Big spender, I am.

https://www.dollartree.com/beacon-foam-poster-board-adhesive-175oz-bottles/307640

Chris

Chris, thanks for the tip!

Wow I didn't think I would find it. Brooklyn is like the wild west. Stocking Dollar Store shelves can be haphazard. I went there Sunday and I found one lonely bottle! I said "don't worry little buddy, come along with me." I ran a test on two different types of joints, a corner joint with a paper tab on one edge (like an A or B fold) and a "T" butt joint.

This glue seems just a bit thinner than BSI Foam Cure, which I've been using exclusively. This smells strongly of acetone, and the bottle says you can thin it with acetone if you like. There aren't really any instructions on the bottle, it pretty much just says "Use me to glue stuff," but I think it's best used like Foam-Tac or Foam Cure - apply to one surface, press the two together to spread the glue, pull them apart, give it a second, then push the two surfaces together again.

For a joint under more stress I'll maybe stick with Foam Cure. I'm not sure if this is as strong as Foam Cure, but on my tests the paper pulls away from the foam before anything else breaks. Hey if the glue's strong enough the glue's strong enough. It IS a wee bit more flexible, so it's the obvious choice for control surface hinges. All in all it's the perfect find. Feels like a Christmas present!

 

[Monte.C]

On corner joints like between the fuselage sides and bottom, using Foam Cure I can clean up the edge with a little sanding block. I want to see how this $1 adhesive handles this. For me it's now down to its general working properties.