Doctor Chinnery Posted December 15, 2020 Share Posted December 15, 2020 It's been a long time since I put together one of Chris Foss's build-it-yourself kits. (One of the early single aileron servo Wot4s.) Anyway - in the building notes Chris strongly advises - insists even, that unless otherwise directed, White PVA should be used, specifically advising against Yellow PVA, or PVA that becomes yellow as it dries/cures. I used Resin W when I built my first Wottie, I see that it's still available and not too pricey. As I recall the only draw back was the length of time that Resin W took to dry. What do other members of the congregation use, that might speed things up a bit, i.e. faster grab/dry/cure times giving at least as strong a joint and with the caveat that it comes out of the bottle white and dries either clear or white? Edited By Doctor Chinnery on 15/12/2020 01:07:25 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted December 15, 2020 Share Posted December 15, 2020 Gorilla Glue white, dries clear, fairly quick grab and dry time and very strong. Quote Link to comment Share on other sites More sharing options...
DaveyP Posted December 15, 2020 Share Posted December 15, 2020 If it's a balsa/ply kit I would use Titebond wood glue, not the fastest to dry but very strong and sands well. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted December 15, 2020 Share Posted December 15, 2020 cyano pretty much everywhere, very thin / hot for most stuff and thick for birch ply / ply. PVA for wing bandages (instead of epoxy or poly resin) and bead foam / wood joins - I avoid the cheapest stuff but I don't deliberately buy expensive fancy PVA slow set epoxy for firewalls and UC mounts contact adhesive for ply doublers and wing sheeting canopy glue for canopies and hinges that covers most things I think Quote Link to comment Share on other sites More sharing options...
Chris Channon Posted December 15, 2020 Share Posted December 15, 2020 Stick ? with resin W. Never had a joint fail using it. Regards Chris.C. Quote Link to comment Share on other sites More sharing options...
John Muir Posted December 15, 2020 Share Posted December 15, 2020 So long as it's a quality brand they're all much of a muchness. Yellow glues are just PVA with an added 'aliphatic modifier' which changes the properties of the glue according to the manufacturer's requirements. Usually it is to make the stuff easier to sand as ordinary PVA is a bit rubbery, but the trade off is it might be a bit more brittle. In practice any decent PVA will produce a joint that's stronger than the wood it's joining so it doesn't really matter. The yellow colour comes from a dye added to make the glue look different. Some white glues contain aliphatic modifiers but just don't mention it on the label. There's even some that are tinted brown. This is all gleaned from much searching about on the internet so don't ask me what an 'aliphatic modifier' is! Quote Link to comment Share on other sites More sharing options...
Phil McCavity Posted December 15, 2020 Share Posted December 15, 2020 I read it that you want to follow the Chris Foss recommendation so White Gorilla is a good choice, it's as good as Titebond and Resin W for balsa with the benefit of being sandable. Quote Link to comment Share on other sites More sharing options...
kc Posted December 15, 2020 Share Posted December 15, 2020 I always use Resin W ( now labelled Evostik Wood Glue - as well as Resin W in small print) available locally but check prices as they vary greatly. Supermarkets sell stuff in green bottles but it is nothing like Resin W! Try a sample of any glue you intend to use and test to destruction - if the wood fibres dont fail before the glue fails then it's not as good as Resin W The first thing I ever glued with Resin W is a cabinet with drawers from 9mm birch ply. Made it about 1966 and 54 years later the joints are still as good as new and still using it in my hobby room. ( 6 years in an unheated shed and 48 in a centrally heated house ) Edited By kc on 15/12/2020 13:12:05 Quote Link to comment Share on other sites More sharing options...
Tosh McCaber Posted December 15, 2020 Share Posted December 15, 2020 I've used Titebind Ultimate for many years (in appropriate areas), rather than PVA, which dries rubbery, and is difficult to sand. Don't know why Chris would go with PVA over aliphatic? does anyone know (maybe best to ask the man himself!) Edited By Tosh McCaber on 15/12/2020 13:30:16 Quote Link to comment Share on other sites More sharing options...
Brian Sweeting 1 Posted December 15, 2020 Share Posted December 15, 2020 Some people recommend certain glues because of allergy concerns. Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted December 15, 2020 Share Posted December 15, 2020 I find that a butt joint made with white PVA can go somewhat flexible in hot sunshine, it doesn't sand well either. I think Foss' recommendation comes from some rather old fashioned thinking. Having built entire models with cyno and being warned that it makes the airframe too rigid and vulnerable to cracking under stress but having no such problem, I conclude that any glue will pretty much do the job. I do, though tend to use aliphatic these days but this tends not to sand too well either. Back to good old fashioned balsa cement I guess. As far as Gorilla glue is concerned there are quite a number of different types marketed under the name Gorilla so it really needs clarification which one is being referred to. A. Quote Link to comment Share on other sites More sharing options...
John Lee Posted December 15, 2020 Share Posted December 15, 2020 Posted by Tosh McCaber on 15/12/2020 13:29:04: I've used Titebind Ultimate for many years (in appropriate areas), rather than PVA, which dries rubbery, and is difficult to sand. Don't know why Chris would go with PVA over aliphatic? does anyone know (maybe best to ask the man himself!) Edited By Tosh McCaber on 15/12/2020 13:30:16 The instructions appear to be unchanged since when they were written, which is 25+ years ago for the Wot4 Mk3. I've the greatest respect for Chris Foss but things have moved on with glue formulations over that time. +1 for Titebond for me. Quote Link to comment Share on other sites More sharing options...
Matt Carlton Posted December 15, 2020 Share Posted December 15, 2020 Evostik Wood Glue for most joints and never had a failure. The only caveat is that it is quite damp so be sure to weigh down things like doublers as it can curl up. If the longer grab time bothers you, I sometimes run a bead with gaps and use CA in the gaps to get an instant hold while the woodglue dries if it's a hard to clamp joint. Doesn't sand well, so wipe off with a finger in a damp cloth. Makes a really good filler with balsa dust. CA for everything else apart from firewalls, wing joints etc where I use epoxy. Stabilit Express used to be my go to for sticking formers in fig/abs fuselages but not seen it for ages. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted December 15, 2020 Share Posted December 15, 2020 "Having built entire models with cyno and being warned that it makes the airframe too rigid and vulnerable to cracking under stress but having no such problem," Sums up my experience with cyano - been using it for donkeys, the wood breaks long before the glue. Those thin applicator tips make the experience of using it much nicer - you can get just the right amount (i.e. very little) on a given joint. Or, as I use, 1.5mm PTFE tube - available on ebay and costs pennies by comparison to the branded applicators. Cut about 2" at a time, and toss it if it blocks up. CA is also excellent for sticking your fingers together, permanently attaching items of clothing to your skin, and is particularly good at joining wood and flesh. Quote Link to comment Share on other sites More sharing options...
Robin Etherton Posted December 15, 2020 Share Posted December 15, 2020 In a past life I used to work for Tate and Lyle and carried out many trials on glues including pva’s. We had about 50+ different formulations of pva in use on the packing machines. Before working on these I had always thought pva was pva was pva, not so. Personally I only use ca these days from the pound shop(4 20g tubs for a quid). Yes it is a little brittle but good old balsa cement is always there for backup. Cant beat ca for a quick build. Quote Link to comment Share on other sites More sharing options...
Phil McCavity Posted December 15, 2020 Share Posted December 15, 2020 Posted by Andy Stephenson on 15/12/2020 14:00:42: As far as Gorilla glue is concerned there are quite a number of different types marketed under the name Gorilla so it really needs clarification which one is being referred to. A. There's only one white wood glue under the Gorilla brand but the brown poly glue is also useful in modeling. Edited By Phil McCavity on 15/12/2020 16:14:34 Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted December 15, 2020 Share Posted December 15, 2020 One advantage with PVA and to some degree aliphatic is that a heat gun can allow emergency disassembly if you make a mistake. Cyano is harder to release and gives reduced working time. Both pva and aliphatic stick well to heat activated covering film . Edited By Tim Flyer on 15/12/2020 17:27:34 Edited By Tim Flyer on 15/12/2020 17:55:59 Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted December 15, 2020 Share Posted December 15, 2020 I use cyano a lot, but I also like Wickes own brand 'Weatherproof Wood Adhesive - Interior & Exterior'. I can't find the word 'PVA' on the bottle, but it looks and feels like PVA, and it grabs very quickly and sands quite well. Much cheaper per ml than small bottles of modelling PVA, and was recommended to me by my local model shop! Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted December 15, 2020 Share Posted December 15, 2020 Forget old fashioned PVA, use Titebond aliphatic for those bits where thin ca is not suitable. I even use ca for firewalls because it soaks right into the wood whereas epoxy will not. The drawback with water based glues is when laminating. As stated above, you can cheat by dabbing a little ca here and there. Another solution is to wet the opposite sides with water which will even out any warping while the wood is clamped and the glue drying. Quote Link to comment Share on other sites More sharing options...
Mastercrashman Posted December 16, 2020 Share Posted December 16, 2020 Chris Foss does suggest that construction with PVA gives joints more flexibility. I use Deluxe Speedbond PVA. It contains a solvent for faster drying. It would appear many PVA glues contain fillers. The Speedbond doesn’t have any fillers and appears slightly thinner/runnier which I prefer. Quote Link to comment Share on other sites More sharing options...
bjk896 Posted January 7, 2021 Share Posted January 7, 2021 I have read so many glue Posts across the waves, I'm a bit confused. I will be starting a new build with Depron. (Its a 48" Herc). I know UHU Por is the recomended glue for Depron but the oneshot placement of components is limiting to an old fella like me. So-o-o-o there seems to be a reluctance of posts to outright recomend or deny PVA, so please - PVA with limitations or PVA only with aliphatic or PVA any old white stuff pupporting to be Polyvinyl acetate or dont touch it with a 40 foot pole ??? Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted January 7, 2021 Share Posted January 7, 2021 UHU por can be used in the 1st few minutes wet/wet Yes, it is incredibly strong when left 10 minutes then mated up in one shot fashion But, as always, if you dry fit 100% certain of being all square 1st, make sure everything fits Then wet both surfaces with the UHU por, and join accurate as possible; you do get some wiggle time.I Otherwise I do use resins for strength Resin W white Titebond yellow Aliphatic Resin yellow Am not a fan of PVA 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.