Looking for advice on reinforcing the FT Arrow w 3D printed center pod

[Jsteketee]

Hi Everyone! I built an FT arrow using a 3d printed center pod. So far the plane has been a blast both flying LOS as well as FPV. I'm having a big problem though with durability. Whenever I have a minor/moderate crash the glue seam between the upper wing and the 3D-printed center pod completely fails. I'm assuming this has to do with the ability of hot glue to grip the 3D-printed PLA. The rest of the airframe is rock solid in crashes due to the packing tape I have covering it.

Could anyone offer some advice on how to make this seam stronger? I've thought about redoing the build using a foam board center pod but I really like the looks and functionality of the 3D-printed piece.

PS Sorry if this is posted in the wrong place I'm new to the hobby/forums. Appreciate any advice!

 

[Merv]

I'd put a barbeque skewer form wing to wing about here, one on top & one on the bottom.
Imbed the skewer in the foam.

 

[RossFPV]

Hi Everyone! I built an FT arrow using a 3d printed center pod. So far the plane has been a blast both flying LOS as well as FPV. I'm having a big problem though with durability. Whenever I have a minor/moderate crash the glue seam between the upper wing and the 3D-printed center pod completely fails. I'm assuming this has to do with the ability of hot glue to grip the 3D-printed PLA. The rest of the airframe is rock solid in crashes due to the packing tape I have covering it.

Could anyone offer some advice on how to make this seam stronger? I've thought about redoing the build using a foam board center pod but I really like the looks and functionality of the 3D-printed piece.

PS Sorry if this is posted in the wrong place I'm new to the hobby/forums. Appreciate any advice!

next time it breaks you can try sanding the pla with rough sandpaper to give the glue more grip.

 

[Piotrsko]

Obvious observation: don't crash and it won't break.

You are dealing with the surface adhesion problem of the glue. You'll either have to increase the bond area or get a glue with better adhesion. I have some really expensive industrial glue that wont fail before the understructure fails, even if it's steel. The art store stuff while cheap is mostly useless

 

[quorneng]

Jsteketee
As you have discovered foam board and PLA don't stick together well. PLA has a completely non absorbent surface whereas foam board is the exact opposite. Any glue that adheres well to the PLA surface will simply pull out of the foam board.
You may have to consider altering you printed nacelle so the wing is actually supported by it so the glue joint works on the paper rather than the foam. It is after all the paper that is giving the foam its strength.

 

[RossFPV]

I'd put a barbeque skewer form wing to wing about here, one on top & one on the bottom.
Imbed the skewer in the foam.

View attachment 235766

If you were up to the challenge you could try to make it fully 3d printed.

 

[FlyingWithRyan]

Lot of subpar tips here in my opinion, the best option would to be to scuff it with some 80 grit sandpaper and then slice marks in the PLA like we do on our servos on planes. This way you have plenty of rough surface to adhere to.

 

[Jsteketee]

I tried some of the advice here but after some more experimenting I removed the power pod altogether and just velcroed the battery to the bottom. This makes it possible to reinforce the top with packing tape along the entire length of the wing.

After making that change the wing is pretty much indestructible. This allows me to fly proximity with the fpv setup and crashes no longer matter!

 

[tamuct01]

I'm not sure exactly what the problem is here. I had that same 3D printed pod and a 3D printed bottom skid in PETG that I used hot glue to attach to the foam. The combo never failed for me. The plane lasted for years until I managed to put it into a tree and cut it in half!

You could try other filaments. Perhaps PETG would be better or ASA for their temperature resistance. It could be the brand/composition of the hot glue you're using. I have other planes with PLA and foam that hold together well with hot glue.

 

[Mr Man]

I'm not sure exactly what the problem is here. I had that same 3D printed pod and a 3D printed bottom skid in PETG that I used hot glue to attach to the foam. The combo never failed for me. The plane lasted for years until I managed to put it into a tree and cut it in half!

You could try other filaments. Perhaps PETG would be better or ASA for their temperature resistance. It could be the brand/composition of the hot glue you're using. I have other planes with PLA and foam that hold together well with hot glue.

3d printer filament has advanced quite a bit in the last couple years too.

 

[Houndpup Rc]

I'm not sure exactly what the problem is here. I had that same 3D printed pod and a 3D printed bottom skid in PETG that I used hot glue to attach to the foam. The combo never failed for me. The plane lasted for years until I managed to put it into a tree and cut it in half!

You could try other filaments. Perhaps PETG would be better or ASA for their temperature resistance. It could be the brand/composition of the hot glue you're using. I have other planes with PLA and foam that hold together well with hot glue.

Wow must never crash your planes!

 

[tamuct01]

Wow must never crash your planes!

I try not to. It's probably due to experience (I've been flying for over 10 years), and job/family keeps me from flying as often as I'd like.

 

[Houndpup Rc]

I try not to. It's probably due to experience (I've been flying for over 10 years), and job/family keeps me from flying as often as I'd like.

Yeah you have been flying a little longer than me.....lol

 

[Piotrsko]

Newbies........ both of you. See below.

 

[Mr Man]

Newbies........ both of you. See below.

I’ve been in the hobby for just over a year. (see date joined). But I fly 3d biplanes and 100+mph flying wings, and everything in between. Minus edf’s, but I’m starting on that too. But I think the only thing I’m no good at is landing with landing gear. I’m so used to belly landers that I have a harder time with gear, but I’m working on it!

 

[Piotrsko]

Secret (DON'T tell anyone) set it up for a nice gentle glide, leave it alone except for avoiding things. IT will land itself.

You will be amazed, and people will applaud.

 

[Mr Man]

Secret (DON'T tell anyone) set it up for a nice gentle glide, leave it alone except for avoiding things. IT will land itself.

You will be amazed, and people will applaud.

I’ll keep that in mind, thanks!

 

[FishbonesAir]

I'm not sure exactly what the problem is here. I had that same 3D printed pod and a 3D printed bottom skid in PETG that I used hot glue to attach to the foam. The combo never failed for me. The plane lasted for years until I managed to put it into a tree and cut it in half!

You could try other filaments. Perhaps PETG would be better or ASA for their temperature resistance. It could be the brand/composition of the hot glue you're using. I have other planes with PLA and foam that hold together well with hot glue.

Yes, I too was thinking "change brands of hot glue". They aren't all the same. This farmer brings this stuff to events that you could practically put real aircraft together with, it's so strong, but rather brittle.

 

[Flying Cherokee]

Secret (DON'T tell anyone) set it up for a nice gentle glide, leave it alone except for avoiding things. IT will land itself.

You will be amazed, and people will applaud.

good to know......especially for my MS WWI biplane I am making, really don't want to damage it.

 

[Houndpup Rc]

I’ve been in the hobby for just over a year. (see date joined). But I fly 3d biplanes and 100+mph flying wings, and everything in between. Minus edf’s, but I’m starting on that too. But I think the only thing I’m no good at is landing with landing gear. I’m so used to belly landers that I have a harder time with gear, but I’m working on it!

Same here: I tried to do it when I was like 10 but it didn't work out so good... But now 7 years later I am doing not toooo bad. I agree landing on landing gear can be hard.