I'm having another go at building a model from foam board

[Mike Freeman]

Hello All,

Back in 1994 I designed the fuz for a model built from foam board.  The model was called "Omnibox" because the fuz was a basic box shape!  It appeared as a free plan in the June 1994 issue of Radio Modeller.  28 years later and having found some very helpful info on this wonderful forum (thank you very much!) I'm having another go, hopefully with a bit more design development and more shape this time!!

It's a flying wing based on my Hi8us design featured in the July 2022 issue which I'm enjoying flying but this new flying wing will have an EDF unit rather than a prop.  I've been talking to George at 4-Max and one of his 50mm EDF units has been ordered!  Two A1 sheets of 5mm foam board have been liberated from Hobbystore costing £8 and I recon I'll use 1 1/2 sheets to build the whole model.  There'll probably be a some balsa/liteply too but only a small amount from my scrap box.  Covering will probably be coloured tape.  A complete airframe for under a tenner.... can't be bad!!

I've done some experimenting with the wing section, doing a mock up of the root and tip sections and this went well so I'll get cracking with the wings and start the fuz design when the EDF unit arrives.  I'm quite excited at this new building experience and I'll post more details as things develop.

BTW I've discovered I haven't got a copy of the June 1994 Radio Modeler with the plan in it.  If anyone has a copy in good nick looking for a good home I'd love to here from you please!!

Cheers

Mike

[Ron Gray]

Spooky as I’ve just started to build the Hi8US!

[martin collins 1]

Watching your build Mike, great stuff to work with, glues:- Hot glue gun for speed but trade off with extra weight, UHU POR either as a contact adhesive or used on one surface like a normal glue, Gorilla glue clear, my glue of choice, light but strong, Gorilla glue white (foaming) good for filling gaps and canopy glue, good for sticking plastic stuff to the foam. 

[Mike Freeman]

2 hours ago, Ron Gray said:

Spooky as I’ve just started to build the Hi8US!

Haha! I hope you enjoy it. I was flying mine at the weekend. Great fun except a blade just clipped a gloved finger on launch! 😬😲 No damage (except a snapped off blade tip) but it fired my enthusiasm for an EDF version!

[Mike Freeman]

2 hours ago, martin collins 1 said:

Watching your build Mike, great stuff to work with, glues:- Hot glue gun for speed but trade off with extra weight, UHU POR either as a contact adhesive or used on one surface like a normal glue, Gorilla glue clear, my glue of choice, light but strong, Gorilla glue white (foaming) good for filling gaps and canopy glue, good for sticking plastic stuff to the foam. 

Thanks Martin. It was your foam board posts that gave me the inspiration to have a go. Thanks, it's quite exciting!!

I've just spent a satisfying few minutes with my film iron removing the paper surface on the inside of the top skin. It's surprising how much weight can be saved, plus it makes the skin easier to bend over the top surface.

The wing section on this model is about 8% thickness and I was a bit anxious about folding the LE over along the 450mm long wing panel but it went ok and is currently on the building board weighed down while the foam compresses on the inside of the LE. Once the tension has gone out of it I'll glue the spars and ribs on the bottom skin and roll the tip skin over.

I was planning on using UHU POR mainly but I like the idea if Gorilla Glue. I have the usual brown stuff. Is the white more suitable or will the brown do?

Cheers

Edited November 24, 2022 by Mike Freeman
Typos

[SIMON CRAGG]

Good luck with your project.

 

During lockdown I built five models from Flite Test free plans.

 

They all went together a treat, and flew fine.

 

Foamboard takes a bit of getting used to, and working with a glue gun means getting a wriggle on when putting parts together!.

[martin collins 1]

I prefer the white expanding Gorilla as it is a lighter colour but brown would be ok as that says foam on the box as well. The clear Gorilla is non foaming, it takes longer to go off but grips really well, a stronger bond than POR i would say and you can spread it nice and thin with a coffee stirrer or scrap wood to keep the weight to a minimum. It is surprising how much weight you can add at the tail of an aircraft using the glue gun! 

[Rich Griff]

Busy day, out and about all over the place for this an that.

 

Could not find uhu por anywhere, Porthmadoc ( predictive text was interesting on that one), Caernarfon or Bangor, not even in Stermat, a good ironmongery/hardware/household stuff type shop.

 

Bought some gorilla clear glue, but at £7.39 for 50ml it had better be good !!!!!

 

Doesn't like EVA foam apparently, ethylene vinyl acetate foam. No idea what that is, it's recycle code or application.

 

Read the clear glue box and seen the triangle exclamation warning. Dangerous to aquatic life but no warning symbol for that on the box.

 

Made in USA, but distributed by gorilla glue Europe. I would have thought the box would have had to display the aquatic life danger symbol ?

 

Anyways off to search the safety sheets.

 

A box of disposable gloves is making its way to my model room.......

 

May I ask please, how much is a tube of uhu por please ?

[martin collins 1]

3 minutes ago, Rich Griff said:

May I ask please, how much is a tube of uhu por please ?

 About £4, the Gorilla glue goes a LOT further than the UHU POR, price per joint is probably comparable or the Gorilla may work out cheaper despite the larger outlay. My local hobby shop stocks POR. POR on Evilbay, includes postage:-

https://www.ebay.co.uk/itm/300864645602?epid=1723178959&hash=item460cee29e2:g:nWoAAOSwo8hTnGRy&amdata=enc%3AAQAHAAAA4FoRT95CLSHVgzPrkEIu8ZWK4ANTeMhH4joZaLQQYywwhk%2F7CUyZTd1%2B4s%2FQk%2Bu6H%2FV%2B1MS08%2F9HRhN81SFca5T0phtKBVCp57k3l9ZfOdnBGOZ9IBpgOZ3uCeSdUPqhE9qezOZ0GejS5RKdj75cBBcccuBeRuHrJLqQHULyIHktNrMp6wwdZs04Gcn%2FBbMstq0wD01690cDXuXKXmD39sBk2HUBxMrn4Sv%2FEcQWBKhROuTHK8oyKBr%2F%2ByU7bjtpC068MHtyRD7XsYNI3w1X76R0jGv5MDCQb5cnQGpdcJyc|tkp%3ABFBM9oaL_JVh

 

[Rich Griff]

Lol lol 😂🤣🤩 joint !! Lol 😂, for god's sake don't go smokin the stuff lol 🤩.

 

But seriousely.....

 

Thanks Martin.

 

Yet to see the safety sheets....

Edited November 25, 2022 by Rich Griff

[Kevin Fairgrieve]

I found that buying UHU POR in bulk works out better.

 

Model Shop Leeds is good for this. £2.20 a 50ml (factored in postage) tube if bought in packs of ten.

 

UHU POR

 

Don`t tell everyone or there will be none to go around.

Good job I just got mine.🖕

Edited November 25, 2022 by Kevin Fairgrieve

[Mike Freeman]

I've made a bit more progress, the wings are now built and I've been experimenting with fuz corners to try and achieve radiused corners rather than a square box shape like my last attempt 28 years ago!! 

I've been using the original brown Gorilla Glue which works a treat!!  I tried to find some of the white stuff recommended by Martin but can't find any at the usual places!!

A question for the seasoned foam board builders please....

The Gorilla Glue instructions say wet one surface to activate the glue.  I was a bit worried about wetting the card so just glued the wings together "dry" in the hope the moisture in the air was enough to set the glue.  It seems to have worked but what do others do please?

I've drawn the fuz up on CAD and I'm hoping the EDF unit arrives tomorrow so I can get cracking on building the fuz.

Cheers

Mike 

[Ron Gray]

No need to wet but will foam more if you do.

Edited November 28, 2022 by Ron Gray

[martin collins 1]

Agree with Ron, i don`t wet, just apply it, still grips well.

[Eric Robson]

Never wet Gorilla brown glue unless you can clamp the pieces together as it expands and forces them apart, 

[Mike Freeman]

Thanks Ron, Martin and Eric. I'll be keeping all the joints water free then! 😁😁

Gorilla glue expands quite a lot without any water and gives a very good bond, I'm impressed! I'm enjoying building with this new ( to me) material. I recon I'll have the whole model built out of 2 sheets of Hobbycraft foam board costing £8. If I'd built it in balsa it'd be 2 or 3 times that!!

Cheers

[martin collins 1]

This is the Gorilla glue i use when i don`t need the foaming stuff to fill joints, it is non foaming can be spread thinner than POR and creates very strong joints between foam and wood etc. Bought mine in B&Q, they do it in smaller packs but i like using the larger round bottle, sorry for calling it white, it is labeled as clear.

 https://www.diy.com/departments/gorilla-clear-glue-110ml/5704947005115_BQ.prd?ds_rl=1272379&ds_rl=1272409&msclkid=d977c6a22193198d6ce6a527d0ec0c48&utm_source=bing&utm_medium=cpc&utm_campaign=Merkle_Standard Shopping_All_Hardware (Bing)&utm_term=4580565453633742&utm_content=2. T - Tool 19 - Hardware&ds_rl=1272379&gclid=d977c6a22193198d6ce6a527d0ec0c48&gclsrc=3p.ds

 

Edited November 29, 2022 by martin collins 1

[Eric Robson]

£122.55 per litre makes fuelling the car a bargain,

[martin collins 1]

15 minutes ago, Eric Robson said:

£122.55 per litre makes fuelling the car a bargain,

Just as well it goes a long way!

 

Edited November 29, 2022 by martin collins 1

[Ron Gray]

If you don't mind shopping on Amazon it's a lot cheaper!

[Piers Bowlan]

9 hours ago, Ron Gray said:

If you don't mind shopping on Amazon it's a lot cheaper!

Yes, for the larger 170ml size £11.10, so half price per ltr.

Looks cheap compared with the Rocket cyano we buy in those little 20g bottles;- £390 kg!

[Zflyer]

Don't know if this helps, when using foam board and 'bending it' to shape curves etc Flitetest recommend using the edge of a table. (See the Masterbuild Corsair on youtube).

I have found the rolled edge of a worktop better than the sharp edge of a table, you don't crush/crease if you tend to be a bit heavy handed. Roll using a bottle to form curves and move onto the rolling pin for tighter curves. (I assume most of us are of an age whose partners use such things)

[Ron Gray]

31 minutes ago, Zflyer said:

(I assume most of us are of an age whose partners use such things)

Still have the bruises to prove it!

[Mike Freeman]

On 01/12/2022 at 17:18, Zflyer said:

Don't know if this helps, when using foam board and 'bending it' to shape curves etc Flitetest recommend using the edge of a table. (See the Masterbuild Corsair on youtube).

I have found the rolled edge of a worktop better than the sharp edge of a table, you don't crush/crease if you tend to be a bit heavy handed. Roll using a bottle to form curves and move onto the rolling pin for tighter curves. (I assume most of us are of an age whose partners use such things)

Thanks Zflyer,

That's a good idea, I'll try that on the 2nd prototype.  I've got a list of things I'm going to try differently next time.  It's been 28 years since I last dabbled in foam board and I'm really enjoying the "different" design development and building a model from something other than balsa and ply.  What other hobby can throw up a whole new avenue of techniques and ideas for someone to try and enjoy after 28 years!!🤣  

Being a flying wing my model has quite a steep wing taper so I used another implement found in the Kitchen drawer.... a pizza wheel 🤣 to score lines in the foam on the inside of the top sheet at the leading edge. I scored 6 grooves in the foam which follow the taper from root to tip.  It's surprising how hard you can press without fear of cutting into the foam but you get some lovely deep grooves which helps bending the top sheet immensely.  Do this on a hard surface and the grooves don't show through the top skin but the leading edge folds nicely round the ribs.

This is a small model with some quite tight curves and I've been using a wall paper edge seal roller to good effect to form them.  I like the idea of a rolling pin though.  I'm sure we've got one but it's not been used in years.... maybe another 28!!

Cheers,

Mike

  

Edited December 3, 2022 by Mike Freeman
typo