A couple more suggestions to help make a succesful canopy moulding. Both require a good deal more work. Most if not all of the commercial small scale vac forming machines have the plastic held in a rigid frame over the body of the machine. The heater is located above the plastric sheet and then the mould is pushed up into the plastic sheet. Once the bed of the machine is sealed underneath the plastic sheet the vacuum is turned on to complete the moulding cycle and the heat is removed. Have a look for machines made by C R Clarke. Another suggestion and a very great deal more work, is to make a female mould. I've used this technique, the advantage is that you can get a good deal of very crisp detail into the moulding and it seems that it is a more reliable method. The cost of course is the amouint of work needed to make the mould.
Thanks for sharing this project with us. I personally really appreciate it since I will attempting something similar later this year. Points I would make, for the future, if I may, (having watched quite a few other video on broadly this subject), and as others have said. In no particular order: 1) maybe a larger sheet, 2) much stiffer/stronger frame, 3) make sure the sheet is thoroughly warmed/heated and absolutely all over, 4) One design I saw was laid out as the following a) a heater box on the left, b) the mould on the right, c) and the frame in the middle hinged so that it could first be position over the heater, and then hinged over the mould - so you don't have to be distracted by considering positioning the hot sheet. 5) Think about how much heat the sheet is losing while you're trying to heat it evenly. It's A LOT. Perhaps consider another radiant heat source from above (later, to hinge out of the way) at the same time as from below. NOT trying to teach you how to suck eggs etc., but the above are definitely things I will look at before my attempts. One other thing depending what you decide on from the above, maybe a frame requiring only one pressure point, so that once the heated sheet is in place, all you have to do is apply pressure at that point. This frame might look like say 4 pieces of 40mm equal angle iron positioned towards (but not at) the ends each of the long sides, and coming together at a central point high enough to clear the mould. Perhaps a long-ish hinged lever (4 x 2 timber) could be used to apply the pressure. I realise that it's a lot of set up for such a short lived part of a build, but who knows, you might become so capable that people will be sending theirs mould to YOU to finish for them! Incidentally, and if I may again, how much will the professional moulding cost? Thanks again for sharing with us Regards Mark in the UK p.s. sorry the above was so long winded.
Thanks for your thoughts, lots of good ideas in that lot. A larger sheet size would probably work, but the ramifications of going bigger are too costly, new heater box, new vac table, sheet price doubling. The cost of having the canopy formed is very cheap by comparison...
Thanks for these Danny .Very informative couple of videos. It's amazing how much time in this hobby is spent not quite getting there. ( Don't ask about the multitude of half finished airframes in my loft...One day ) And yet still the satisfaction is in the trying. I had a similar biopsy last year and it's surprising how quickly the face heals. Hope all is well. I'm sure it will be Take care.
Only halfway through watching this video, and thinking if it is possible to carry the plug with the vacuum attached to the heating oven and placing it on top of the sagging plastic, use the heat of the over to assist. You may need a larger sheet and a stiffer frame to hold it
Unfortunately the plug would not survive the excessive heat. But a similar idea had drifted through my noggin, resting the uturned plug in the heated plastic and let gravity take over. Anyway its on its way to a proper vacuum forming company now, lets see how it comes out.
Hi, the deep heater box is to even out the heat, a buffer, this was learned from watching several vac form videos. A different (hotter) element might work. But I have sent the plug away for forming.
@@cammnut Then the next thing I would try would be to use plastic that is about 20% to 30% larger in area. That will give more plastic to stretch over the plug. After viewing the vid the second time I think that is what I would do. I have done some limited vac forming in my modeling career but never at this scale.
Yeah it's the Scale of this and the thickness which is proving hard. I get 4 sheets out of a full petg sheet, the full sheet is £50 if I make the pieces I use bigger, I can only get two out of each full sheet, which effectively doubles the material costs. My table, heater box, and frame would all need remaking. So it's not going to happen. I will let the professionals do it. My A4 vacforming has worked fine, so the process works, just not cost effective for one off molds like this. But thx for your thoughts.
