Edgeflyer Posted July 21, 2020 Share Posted July 21, 2020 Hi all you kit and scratch builders! I am wondering what folks' experiences are with modern filler systems? I have used epoxy resin mixed with glass micro spheres to create a reasonably lightweight filler. It is a bit of a faff, messy and not that easy to sand next to soft balsa. I find lightweight filler of the "one shot" variety good in some contexts butnot strong witb poor adhesion. No good for areas to be carved. Recently I've tried acrylic 2 part resin. Easy to use, clean and quick setting, but much too hard to sand and terrible adhesion. Does anyone have helpful suggestions of good modern fillers suitable for aeromodelling? Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted July 21, 2020 Share Posted July 21, 2020 Nothing modern about what I often use. It is a mixture of Bucks Composites lightweight fairing compound and Halfords polyester resin. The thicker you make it the easier it sands and you have time to shape it before sets really hard. Years ago this was available commercially from Germany so I just copied it. Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted July 21, 2020 Share Posted July 21, 2020 I mix micro balloons, cordial silica or the fairing compound from Bucks composites with emulsion, the trick is not to have it too wet but a nice stiff paste, you can get the match pots in the usual outlets I tend to take some balsa with me to get a near as possible match, Let it dry overnight is preferable but not essential, it sands as easy as the bought fillers but it a little denser and does not crumble away, it feathers out very well, if filming over I tend to sponge on a light coat of basaloc to be belt and braces with it. I have tried mixing with the water based resins and found the emulsion a better option. Quote Link to comment Share on other sites More sharing options...
Edgeflyer Posted July 21, 2020 Author Share Posted July 21, 2020 Thanks, I'll l try the emulsion method, I hadn't thought of that I would have guessed it woulde be a bit soft. Does it set quickly. I wondered about polyester resin too as it sets quickly. Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted July 21, 2020 Share Posted July 21, 2020 Hi Phil Yes it does set quickly, obviously it it goes on thick it takes longer but I only put it on in roughly 2mm thickness at a time, it did take me a few goes to get the mix right but it is not difficult, I found Poly C worked but just lacked something in the sanding but that could be I needed to experiment more, possibly the emulsion being a little thicker was easier to get the mix right, I also found mixing emulsion to the micro balloons a better way as you don’t need that much, also found the bought lightweight fillers can dry out and not work, I added a little emulsion to these and this works well too!👍🏻 Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted July 21, 2020 Share Posted July 21, 2020 Polyester can be as fast or slow as you like, just experiment with the quantity of hardener ( you don`t need much!). Quote Link to comment Share on other sites More sharing options...
kc Posted July 21, 2020 Share Posted July 21, 2020 I hardly ever use filler, but prefer to put a drop of water onto any dents in the balsa ( they come out like magic!) or if too deep I insert a bit of balsa and sand down. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted July 21, 2020 Share Posted July 21, 2020 I find the lightweight fillers from the DIY store useful for dings & marks. If you pick up the tub & it feels empty you've got the right stuff... This is the stuff currently on my shelf.... **LINK** No good for carving & suchlike but perfect for gaps & gouges. The classic dope & talcum powder mix takes some beating for such application too.... Quote Link to comment Share on other sites More sharing options...
i12fly Posted July 21, 2020 Share Posted July 21, 2020 DeLux products lightweight filler for me but to help the adhesion I coat the wood with a thin coat of Fast Tac from the habardashery shop and let it dry before applying the filler (now that Balsaloc is gone) Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted July 21, 2020 Share Posted July 21, 2020 i12fly, Deluxe Materials has Covergrip which is a superior version of Balsaloc. A. Quote Link to comment Share on other sites More sharing options...
Richard Clark 2 Posted July 22, 2020 Share Posted July 22, 2020 I use the lightweight version of Polycell filler. It'a cheap, excellent, and you can get it in any DIY store. Quote Link to comment Share on other sites More sharing options...
Richard Clark 2 Posted July 22, 2020 Share Posted July 22, 2020 Posted by Steve Hargreaves - Moderator on 21/07/2020 15:39:13: I find the lightweight fillers from the DIY store useful for dings & marks. If you pick up the tub & it feels empty you've got the right stuff... This is the stuff currently on my shelf.... **LINK** No good for carving & suchlike but perfect for gaps & gouges. The classic dope & talcum powder mix takes some beating for such application too.... Spot on. Almost all these 'specialist' model plane materials are only re-packaged regular stuff anyway, Edited By Richard Clark 2 on 22/07/2020 05:40:39 Quote Link to comment Share on other sites More sharing options...
Bruce Collinson Posted July 22, 2020 Share Posted July 22, 2020 Polyfilla Advanced, comes in tubes, light, fast drying, good adhesion, smooths easily, sands readily. Significantly superior to “specialist” modelling fillers which I’ve tried. By no means all retailers stock it. Worth tracking down. BTC Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted July 22, 2020 Share Posted July 22, 2020 I use Gorilla glue for any filling that needs to be shaped and also needs a little more of a bond such as a fillet or snake exit, otherwise if it's just a ding that water won't eradicate then whatever filler I have left from decorating. kc has a good point in that anything big enough to give concern can easily be filled with soft balsa and sanded flush. I'm just lazy and use GG as it can be moulded almost to finished shape with a bit of masking tape. Quote Link to comment Share on other sites More sharing options...
Bruce Collinson Posted July 22, 2020 Share Posted July 22, 2020 Which reminds me, did you know that the Geordie Dating Agency (*) now stocks polyurethane adhesive in cartridges? From memory c. £10, not hugely more than a bottle of GG but with the prospect of it not going off in a nanosecond as the air is automatically expelled. Also a neat, accurate dispensing method, as long as you can get the nozzle in. BTC (* Screwfix). Quote Link to comment Share on other sites More sharing options...
Nick Somerville Posted September 12, 2020 Share Posted September 12, 2020 I’ve read about Acryl-red Glazing Putty on a number of forums and its use for filling pinholes post glass cloth work and also for minor deviations around fillets etc. Well it’s pretty pricey stuff but I went ahead and ordered some as the very fine lightweight fillers discussed on this thread are too grainy for pinholes and their adhesion and surface strength is also lacking unless used prior to glassing. Well my tube duly arrived today and I have put it to the test. It is not light at all but for what I need it for it is going to be ideal. Easy to apply, quick to dry and sands beautifully for a primer ready finish. Just need some other uses for it now as a 409g tube will be easily enough for over 100 large models and I am not going to be around that long! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.