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View Full Version : Venom 1/8th GPV-1 Fairings...


Daddy MACK
09-05-2009, 05:31 AM
Hey guys, thought I would start a new thread for my attempt at making a fairing set for the venom 1/8th bikes...

Here's a run down of where I'm up to...

First I used the standard fairing set as a mould, I simply taped all the areas that would allow the plaster to escape. After that I smeared a thin layer of cooking oil inside the fairings to allow the plaster to release... Then I mixed some plaster up, up poured it in...

Once the plaster had set I removed the origanal fairing(popped realy easy too), I then drilled the mounting holes deep into the mould to maintain a fixed reference point...

Then I went about adding plaster to defferent areas to change the shape, and started filing and re-shaping...

This first attempt is ment to be the Ducati Desmosedici 2009, motogp bike

here's a few pics of the half done moulds...

Daddy MACK
09-21-2009, 07:34 AM
Hey Blokes... I've tried many times, many different ways, but no joy !!!

I can't seem to keep the poly-carb hot enough to form, and the 'VIVAK' didn't seem to get anywhere near flexible enough to form eigther....

If anyone out there has any advice what so ever, please let me know...

I have spent heaps of time gettin this stuff ready, and I think maybe some people would be interested in some different looking body work,

I think I really need a stronger sucker thing (given up trying to spell vaccumme)

toyranosaur
09-22-2009, 07:39 AM
Hmmm, only 3 things could basically be wrong: Not enough heat, wrong plastic properties, or insufficient vaqoome (That's the proper spelling. :nice:) I have not done it myself, but did build a nice vac unit as described in "Do It Yourself Vacuum Forming", an inexpensive book for the beginner. You need 2 vac sources, a big-volume one like a Hoover to quickly evacuate 90% of the air, and a hi-vac source to really suck that :censor: down tight. The big source moves a lot of air quickly, but without much force, whilst the hi-vac source moves very little air but with a lot more power. The design in the book has a simple valve that kicks in when the big source has done its job and automatically engages the hi source, since this must all be done REAL quick-like or the plastic will lose heat. The unit I built cost about $27-ish, and I made it to use one of those 'Foodsaver' thing's Mason-jar tube attachments as the hi-vac source, since we already had one. If not, you'll need a vac pump: The book goes into this as well as plastics, heating methods, etc. I don't know what you've read on the subject, so forgive me if my suggestions from 1 cheap beginner's book are like "Duh!!" Wish I had the time & was set up to try mine, but if I can be of any help, I'll do my best! Congratulations on your perseverance Mate! Chris

Daddy MACK
09-25-2009, 11:23 PM
I hear what your sayin Chris, I've tried a few more times but still can't keep heat in the plastic, as soon as the vvaaqquuoooomm is turned on, the plastic cools instantly. Only a house hold vac. as well. I quized the local plastic supplier about the material required, and poly-carbonate is the best for the job, but the hardest to work. the other product is called VIVAK, similar properties, but works at a lower temp.... so they say... I've tried it and seems to cool even faster than the poly-carb, and it also goes smokey with too much heat...

I did some vac. forming years ago at high school, pretty dodgey set up, in that it leaked all over the place, but it was very simple and effective... the difference here was we were useing styrene, that stuff is very versatile when it comes to forming.... only problem for what I want is, it's brittle (no good for the venom bike that will no doubt be cart wheeling down the road pretty often) but also being able to paint from the inside.....

I think I'm just goin to have to go find a better heat source, and a better vac., I looked at getting a vac. pump a while ago, but can't seem find any used units, and the new ones where way too pricey.....

I'll keep pluggin away... can't be that hard..... can it ???

toyranosaur
09-26-2009, 06:55 AM
Just keep throwing fistfuls of money at the problem, it'll have to work eventually! :lol: Sounds like you need a bit more heat, a lot more vakumme, and a quicker heat-to-forming time.....(Good thing you have me to tell you all this! :p ) I remember reading that it's a good idea to pre-warm your molds as much as you can, or no matter how hot the plastic, it's so thin that it'll cool on contact. Made sense to me! Another thing was to build a heat source using oven heating coils that's mounted vertically directly behing the former: The frame that holds the plastic is hinged and rests right next to the heating coil when open. You heat the stuff 'til it's droopy, than BAMMO!! Shut that thing real quick-like-The vac should already be turned on- and there is no time lag between heating & molding, unlike when ya gotta grab it outta the oven, position it, and waste a critical second or two. (The heating coil doesn't move, just the plastic-holding frame.) You must anticipate that, while simple, it's obviously not the easiest process in the world or more chaps would be doing it. I wish I wasn't between moves & had a couple $ to find mine & check it out, I just never got around to it.....Maybe when I get the shop rolling? Your perseverance is impressive Mate, keep at it! :nice: Chris

holdenhz
10-04-2009, 07:50 AM
Have a look on you tube for the 1/4 scale gravedigger build.
He has one episode on vac forming his body,showing the whole process.
Could be helpful

toyranosaur
10-07-2009, 07:23 AM
I couldn't find it, just a pic of his proto hood. Got a linky? Chris

holdenhz
10-07-2009, 09:55 PM
I couldn't find it, just a pic of his proto hood. Got a linky? Chris

http://www.youtube.com/results?search_query=1+4+scale+grave+digger&search_type=&aq=1&oq=1%2F4+SCALE+

Down towards the bottom of the page

toyranosaur
10-08-2009, 06:14 AM
Aha! Found the one with the body mold, but it's a long way from showing the process (Wrong one mebbe, but I don't need to go through all 13 vids.) His work is, IMO, not to be emulated anyway-it's all substandard, sorry. I did find a LOT of vacuum-forming vids, but they still didn't tell me anything I didn't already find out from the book 'Do It Yourself Vacuum Forming'. All the home-built jobbers seem to only use a Shop-Vac or such, and no one uses the critical low-volume, hi-pressure secondary vac source: I think this is key, and if this step is omitted, well, ya get what ya get. The process is too simple to have TOO many variables to troubleshoot, I would think. I should dig mine out & get some Lexan to experiment with. Chris

Daddy MACK
10-14-2009, 10:19 PM
Hey guys, I haven't watched the vid yet, But I do have a plan.... probably not a real good one.... but still.. it's a plan...

I'm going to get me an old electric oven, tip it upside down, change my plastic vaquoom fitting for a steel one I've made, get some heat resistant hose....

so.... then.... I take the now inverted oven, so the heating element is located above the vaccccume box (and the plastic), then hopefully the heat will pre heat the box, the moulds, the air, and of course the plastic....

that's it !

what do ya recon, should work hey ????

Oh.. forgot to mention turning the vac on, and also the implimentation(big word so I sorta look klevar) of the vac pump, otherwise known as, Chris s suggestion, sounds like the way to go mate. I bought a used unit from ebay, for just $30, still waiting for it arrive though...

So with plenty of heat... and plenty of suction... this has to work.... and if it doesn't, then I try something else....

...Luke...

toyranosaur
10-15-2009, 06:02 AM
Hmmm! So, yer gonna heat evr'thang up a bunch? I wonder if any of the materials used to construct the box, molds, etc. will not also soften? Sounds like you've considered this, and I admit the whole approach of "SCREW IT!! I'm a-gonna show YOU pieces of !##%**! what HEAT is!!!" does appeal to me. :lol: That and the vac pump sure should make a difference! If you do manage to weld/melt everything into one solid mass, by all means post a pic for us though. :lolbeat: Keep us posted Mate! Chris