Toughening up foam

Morning all.

Has anyone ever tried covering polystyrene foam with anything to try and increas it's "ding" resistance, without adding too much weight? Just looking for ideas.... Whatever it is, it needs to accept a bit of paint afterwards

Andy

You can glass it.

Roy

used white wall paper lining and paste.In fact any wall paper just turn the pattern bit over.

Andy, there was a water based acrylic floor varnish, from B&Q, that you used with tissue for skining bare foam - but I can't remember its name or locate my reference to it just yet. But, I think THIS is similar. 'SkinCrylic' is probably more expensive.

Hi.
Have a look here - this lad is obsessed with foams and high heels
http://translate.google.com/translate?hl=pl&sl=auto&tl=en&u=http%3A%2F%2Fwww.motylasty.pl%2Fwarszt_4.html%23warsztat

PS.Wikol is a wood glue - white and thick (like a cream) tested by many - does the job.

THIS thread from the RCM&E forum looks like it may be of use.

You can get the PolyC from HERE Glass cloth and resin would be too heavy.

Tissue applied in layers with water thinned PVA adhesive. Let each coat dry. Old cheap technology but still works well. Use Balsaloc, then you can use iron on solarfilm or similar direct afterwards.

Try these 2

FLITEHOOK
42 PLAYERS CRESCENT TOTTON SOUTHAMPTON HANTS S0409AZ
TELEPHONE / FAX 023 80861541 e-mail flitehook@talktalk.net
www.flitehook.net
John and Pauline Hook
"Flitehook started in 1980 part time but when John was made redundant in 1983 we decided to go full time. We started with just the wood and it then developed into what we have now".
They attend most free flight events, list on their web page.
You just have to see the stuff they have available.

Or
Mike Woodhouse's site

http://www.freeflightsupplies.co.uk/
Vast range of modelling gear but again specifically for the free flight model builder

Or you could STOP MARK flying your models.

Roy

Anyone ever used brown paper and PVA? Just wondering how it conforms to curvature, lumps and bumps, and whether it needs sanding and faff to get a reasonable finish on it? Tissue sounds like it might be easier to get it around corners though.

Is the PVA/paper(or tissue) finish waterproof? Can I use waterbased paints on it afterwards?

And I like that idea Roy, it's got mileage....

Andy

Brown paper - HEAVY. Also, requires slicing into fingers to go round curves. Use water proof PVA. Doesn't sand to well. Not very light. Water based paints OK. The best and lightest route is PolyC and tissue. Very little additional weight, sands OK, is water resistant and OK for water based paints. It can also be coloured before application - follow links on sites previously provided.

My first wife was a dress maker and used to have loads of dress lining offcuts which I used to snaffel (not sniff u understand! ) the point is, I used pva and this nylon like fabric which has an open weave and conformed to curves readily.
On my colt sloper (which had a abs plastic fus) I used this fabric with araldite.
I think you need an open weave cloth to achieve a multi curve.

I'm liking the look of this poly-C stuff. Seems to do the same job as epoxy when glassing, but is water based, and easy to clean up!

Cheers guys
Andy

ROYB wrote:Or you could STOP MARK flying your models.

Roy

Dont see how thats relivent, its been literaly 12 days since i crashed a model that wasnt mine!

Who cares anyway its a crap hobby


Andy speak to Leigh, he has skined lots of foam models

I have used brown paper on a number of models. You have to use the right stuff or it is much too heavy. The 'right stuff'' is thin, crinkly and somewhat resembles cheapo christmas gift wrap in thickness and texture but is much more fiberous. I've never used it with foam but when used with balsa makes a very bullet proof and strong covering. The weight increase is small for the strength. I apply it with pva/water 50/50 and it takes all paint finishes I've used. Very good for small tough models with good bouncability, not so good for things that require a pristine finish

andy poly c is just water based polyurethane varnish with pva added. dig around a little and you wil find that many industrial outfits use polyurethane as a water based resin. tissue isnt all that tough and will ding very easily but it does give a good finish.

for best results go for glasscloth with normal skinning epoxy. it wont melt the foam and is tough as old boots.
if you dont fancy the epoxy route get yourself a tin of ronseal matt waterbased polyurethane, the floor varnish i think is called diamond hard and is the best ive found. use a thin first coat to stick the cloth then sand and add flow coats till your happy with the finish. then paint with whatever you like.

to help the flow coats you can add polycell one fill or any other lightweight filler to the varnish. just make sure you seal it.

L