Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[para_handy]

Can someone tell me if it has to be blue foam that you use when making a plug.

[gribeauval]

Can someone tell me if it has to be blue foam that you use when making a plug.

Most of it isn't blue anymore!  It can be pink or cream coloured as well.
Just make sure it's extruded polyurethane and not expanded polystyrene.
I use 4'x2' insulation panels from Wickes DIY, the ones with the metal foil backing which peels off.


Mike

[Circlip]

ExPanded foam, Usually white and is composed of big white bubble lumps and is normally used for packaging, tends to crumble into big lumps when sanding etc. ExTruded foam, blue, pink, cream or orange (B&Q) has a finer structure and sands to "Dust".
 
  Cheapest way to make a plug is to block out a framework and then skim with a sandable layer to impart a fine finish, so the cheaper foam to use would be expanded, don't forget, after you've made the female master, the plug is scrap.
 
 T'other way is to make a plug in blue (?) foam, skin with EPOXY laminations and the dissolve the core using Acetone. doing it this way saves the intermediate step but means a lot of sanding on the outside to give the hull finish.
 
  Using Polyester resin direct onto polyStyrene foam surfaces dissolves them.
 
   Regards  Ian.
 
 
  PolyUrethane foams are different.

[Colin Bishop]

There is a very good article in July 2013 issue of Model Boats by Ron Rees who has built a Fairey Huntsman using polystyrene foam.
Colin

[Neil Martin]

I would like to echo Colins recommendation regarding Ron Rees.
He did a talk to our club members earlier in the year about this subject.
He brought along examples of the construction process at various stages.
He also likes to make the most of using recycled materials during his builds.
In short, he can produce a hull in an extremely short space of time,
& at very low cost compaired to some more traditional methods.
Well worth a read.
 
Neil.

[Circlip]

And don't forget our own master of frugality Krishna.
 
  Regards  Ian.

[Big Ada]

Yes what has happened to Krishna ?.
 
Len.

[Subculture]

Perhaps he's shaving his legs.

I use the yellow polyurethane foam, the stuff they use in loft conversions. Do take note however, that they tend to also fill that stuff with ground glass (itching powder) so wear gloves and a respirator when sanding it.

I only use foam if I'm making a plug with lots of compound curves and treat it like a soft balsa. If it is hard chine or of very straightforward construction I prefer to use more conventional techniques, using either wood or better still plastic sheet (e.g. plasticard, but make sure it's coated well with the 2K paint, because it's styrene and will melt with polyester resin)

When making a master with this foam, I always apply glass matt or cloth over the surface with resin, this makes it super tough, I then use polyester filler to get the final finish. First master I made using foam, I used polyester filler directly over the foam. It worked, but the master was extremely fragile, as filler has zero tensile strength, one little ding, and I knocked a hole in the finish, so if you use filler only you need to build up a thickness of about 3 or 4mm to get sufficient strength. I find the glass matt/cloth technique easier, and cheaper.

Polystyrene foam works as well, but make sure you coat it well either with polyurethane varnish, oil paint, epoxy resin or PVA glue before touching it with polyester resin for the reasons that circlip mentioned.

[murphy1570]

Hello folks
I agree with Colin and other members re the article by Ron Rees in the July issue of model boats regarding using Styrofoam to build the Fairey Huntsman as designed and built by unfortunately the late Richard Webb using styrene, I got to a similar stage to Ron ie all the bits cut out etc, but for the life of me just like Ron even with the help!! of her indoors the bloody thing kept falling to bits despite copious amounts of masking tape holding it together, no doubt due to my ham fisted efforts!!. I have decide to follow Rons method of using reclaimed styrofoam which I acquired some time ago from a builders skip, I to have all the card templates that I made for the styrene version to use in the foam version.
 
Ron mentions using 2 part epoxy finishing resin he used Pacer Z- Poxy finishing resin over his wifes old tights on the hull, can anyone tell me where to obtain this by mail order and also how to apply it, is there an article/feature on the site that shows how to use it to get a good finish, I searched but couldnt find one, no doubt due to me. Has anyone else tried Rons method of building the Huhtsman/
 
Thanks folks all the best,John.
 
Thanks

[Big Ada]

Hello folks

 
Ron mentions using 2 part epoxy finishing resin he used Pacer Z- Poxy finishing resin over his wifes old tights on the hull, can anyone tell me where to obtain this by mail order and also how to apply it, is there an article/feature on the site that shows how to use it to get a good finish, I searched but couldnt find one, no doubt due to me. Has anyone else tried Rons method of building the Huhtsman/
 
Thanks folks all the best,John.
 
Thanks

His wifes old Tights may not be available Mail Order!..

Len.

[srcampb]

A quick question, if i could..
 
Can polyester resin be used over polyurethane foam?
 
I've built hulls plank on frame and then sealed them with polyester resin, so that's what I'm familiar with. EPOXY resin sounds like a whole different thing..
 
Many Thanks!

[Circlip]

Nothing to fear with Epoxy (apart from some having an allergic reaction to it) Look for information on "West Systems"
 
  Regards  Ian.

[murphy1570]

Thanks for the replies folks I have had a look on the West Systems site as recommended by Ian and it is full of useful information of epoxy resins and using them, any more info re my question would be great, re anbody else who has had a go at building the Ron Rees foam version of the Fairey Huntsman, I have started on it and have cut the hull profile to shape, using a bit of recycled pink foam ie rescued from a skip years ago and has been lying around in the garage ever since till I found a use for it, I was surprised how easy it is to work with and the hull profile was cut out in no time using the card templates I had made for the styrene version. I had similar problems to Ron when trying to tape and glue it together (due no doubt to my ham fisted attempts at following the sadly late Richard webb's method), I have built other styrene bits and bobs using Richards methods and found styrene a great material to use due in no small part to following his excellent book and DVD on using this material. I am now at the stage of shaping the hull with it's various curves and deck camber, if this is succesful I will have to try and explain to my good lady wife why I need a pair or at least one leg of her old tights!!! to cover the foam hull. Then if I get that far have a go with the two part finishing epoxy resin and see what type of finish I end up with as this will be my first go at using it.
Will let you know in part two of this saga how things go, again any help /advice greatfully accepted.
 
Thanks again folks all the best,John.