geoff wise 1 Posted February 18, 2021 Share Posted February 18, 2021 Hi, I am in the process of building some 1/2 A models for my Grandson, who wants one with a canopy so he can put a proper pilot in ( smiley) I was going to go on the lines of a plunge mold, but before i start, what is the best material to use and where can you get it from? I don't really want to use the pop bottle method. Any suggestions would be welcome. Thanks, Geoff Maximum length will be about 5" Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted February 18, 2021 Share Posted February 18, 2021 PETG sheet is usually what is supplied when you buy a commercial vac-formed canopy. Around 1.0mm thick. You can buy A4 sized sheets from Trent Plastics which seems quite convenient. I haven't used them, but am planning to soon. https://www.trentplastics.co.uk/clear-petg-sheets Quote Link to comment Share on other sites More sharing options...
Steve Houghton Posted February 18, 2021 Share Posted February 18, 2021 Geoff, Sarik themselves sell sheets from 0.5mm up to 3mm thick: PETG Quote Link to comment Share on other sites More sharing options...
Eric Robson Posted February 18, 2021 Share Posted February 18, 2021 Sarik also sell ready moulded canopy's Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted February 18, 2021 Share Posted February 18, 2021 But the OP wanted to mould his own! Quote Link to comment Share on other sites More sharing options...
geoff wise 1 Posted February 18, 2021 Author Share Posted February 18, 2021 Good evening. I have looked on Sarik in the past and they don't seem to do what used to be called universal canopies with different sizes, but i will give Trent a call tomorrow, A3 sheets are quite cheap so i will have a word with them. I do want to mould my own to find out if i can. More satisfaction. I will let you know how i get on? Thanks Geoff 1 Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted February 18, 2021 Share Posted February 18, 2021 This is my setup which consists of an ali frame and a box which connects to the vacuum cleaner. I made the frame to fit in the grill slider ways in the cooker. The box is a simple plenum with holes drilled for suction and some draft strip to seal the frame. I clamp a piece of 1mm PETG sheet to the frame. Heat it under the grill till it starts to sag then with the vac cleaner running I quickly take the frame and push it down over the plug located on the box until the frame seals on the draft strip and the vacuum pulls it tight. I have made two perfect canopies for classic aerobats this way. A. 1 Quote Link to comment Share on other sites More sharing options...
geoff wise 1 Posted February 19, 2021 Author Share Posted February 19, 2021 Hi the PETG is on order as you will see I am in a bit smaller size than you. Club 20 and now Club 020 Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted February 19, 2021 Share Posted February 19, 2021 My setup is similar to Andy's but less sophisticated (IE more bodged!). Heat source is a box built around an old toaster element, while the vacuum box is a plastic draw from Ikea with a perforated chipboard top. Seen here in use vacforming 1mm ABS Spitfire spinners. Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted February 19, 2021 Share Posted February 19, 2021 Alan, Is that heater connected to the mains electricity, that looks dangerous! Also why does the heater box have to be so deep, is it to even out the heating of the material to be moulded? Andy. Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted February 19, 2021 Share Posted February 19, 2021 It's not dangerous in the sense that all the metal parts are safety earthed and you don't come into contact with it in use. I also use an RCD socket just in case. It is deep because I found with a shallower box I was getting localised hot and cold spots on the plastic. Increasing the depth has solved that issue nicely. Quote Link to comment Share on other sites More sharing options...
geoff wise 1 Posted February 19, 2021 Author Share Posted February 19, 2021 Andy is that a plaster cast plug ? Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted February 19, 2021 Share Posted February 19, 2021 Alan, I guessed the box was set up for even heating, however, it's interesting because I use a cooker grill which works perfectly well where the spacing is a lot closer. Geoff, Yes I cast all my canopies in plaster because you simply don't know if a replacement is going to be available. That one you can see was cast in builder's finishing plaster and took a few weeks before I could de-mould it because it takes an age to dry out. I use plaster-of-Paris now because it dries quicker. Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted February 19, 2021 Share Posted February 19, 2021 Yes but when using the grill inside the oven my guess is that the heat is contained by the oven itself and can only evenly heat the plastic. I have to do my vacforming in my workshop which does not have the luxury of a cooker, so had to use trial and error to get the box as needed. Quote Link to comment Share on other sites More sharing options...
Roy Thompson Posted February 20, 2021 Share Posted February 20, 2021 Interesting read. My setups is very similar to what your all using, my heat source is a secondhand baby bellini cooker. Small enough to live in the garage, with oven door closed plastic heats up nicely all over. Quote Link to comment Share on other sites More sharing options...
kc Posted February 20, 2021 Share Posted February 20, 2021 For anyone who does not want to mould it himself Vortex Vacform supply lots of different types of bubble canopies or scale ones. They also make dummy radial engines etc. Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted February 20, 2021 Share Posted February 20, 2021 And for everyone else who IS interested in moulding their own: that is what this thread is about! Quote Link to comment Share on other sites More sharing options...
kc Posted February 20, 2021 Share Posted February 20, 2021 Sorry if that offended you Alan and I had noted you previous comment. However Vortex are not a very obvious supplier so i thought it worth mentioning it here. Relevent to the original enquiry is the fact that Vortex also do pilot mouldings mostly quite a large size but they also do a sheet of 10 small 30mm by 30mm which may well be of interest. Quote Link to comment Share on other sites More sharing options...
geoff wise 1 Posted February 21, 2021 Author Share Posted February 21, 2021 HI at the size of models I am making 22" to 36" span. There are not a lot out there 3" long. And on unless I see it in my hand I can not tell if it is what I want. So I want to have a go Dexter has been helping. Geoff. Quote Link to comment Share on other sites More sharing options...
Manish Chandrayan Posted March 4, 2021 Share Posted March 4, 2021 Are Vortex still in business? Tried to access their website it failed to connect multiple times. I was looking to order some cowl for the Nijhuis Wellington Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted March 4, 2021 Share Posted March 4, 2021 @kcalways good to have a bit of lateral thread drift! Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted March 4, 2021 Share Posted March 4, 2021 Manish, They may have been updating the site when you tried, it works this morning. A. Quote Link to comment Share on other sites More sharing options...
Manish Chandrayan Posted March 4, 2021 Share Posted March 4, 2021 Thanks Andy, yes I am able to log in now? Quote Link to comment Share on other sites More sharing options...
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