marc37i
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What would be the best gun to use for spraying small molds? would an airbrush work or would a small spot repair gravity fed be better?
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Carbon Tuner
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Well All I have is a big top feed gun, I can use this in the future buut a bit big for the size of parts I will be starting with. I plan to go to the local tool store an see if they have a automotive touchup gun. In my air brush searching I found "PAASCHE AIRBRUSH" # 62-1-3 is looking nice for smaller stuff" I have some 1/32 wax I am waiting to get here. I plan to make a side mirror cover. I was sitting there buffing my part out and realized I cant just make the mould of this I need some type of thickness on the part to compensate for the part thickness.... So no need to polish the part, but I never worked with the sheet wax beforeSo I guess I will be doing a bit more work in the mould but with this small part should not be a big deal.. Now "
If Brute Force Isn''''t working your not using enough...
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Warren
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Have you tried a chemical semi-permenant release agent such a easylease or similar?
You will get a easier release than with wax, plus easylease can leave a nice gloss finish if the mould is highly polished.
Ive always found wax releasing is the hardest, but PVA causes surface finish imperfections that need polishing out.
however with easylease ive found if the mould is shiny, then so is the part straight from the mould.
Would kind of maximise the benefit of a cosmetic gelcoat if it comes out super shiney to start with. Plus save you time in finishing.
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Carbon Tuner
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Cool, yes I think I will try that next. I did post somewhere around here that the wax and pva coating is starting to be the most imperfection problems..
I have been cutting back on waxing, was like 5, then 3 then 2 coats. When your mould is real shiny its easy to see the wax. Also after the wax a light coat of pva.
As far as waxing If I can see the haze over the mould I'm good right? I think I could get away with waxing one time and a quick coat of pva. the thinnest coat of wax will work as long as its evan and completely covered??
Wish I would bought this stuff when I was ordering the other day.... The shipping to USA drives me insane!!!!!!!!!!!!!
Next round I guess...
If Brute Force Isn''''t working your not using enough...
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Warren
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in theory as long as you have a 100% even coat of wax in one hit then fine. However usually you do multiple layers to garuntee that 100% coverage.
With a chemical release agent its much quicker to apply and only needs 1 or 2 coats per pull from the mould if youre doing infusion.
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marc37i
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Carbon Tuner (30/06/2012) In my air brush searching I found "PAASCHE AIRBRUSH" # 62-1-3 is looking nice for smaller stuff" Typical! cannot find anyone stocking this gun in the UK. I have some 1/32 wax I am waiting to get here. I plan to make a side mirror cover. I was sitting there buffing my part out and realized I cant just make the mould of this I need some type of thickness on the part to compensate for the part thickness.... So no need to polish the part, but I never worked with the sheet wax before
So I guess I will be doing a bit more work in the mould but with this small part should not be a big deal.. Sheet wax can be a right pain to get right on very curved surfaces like side mirrors. What I have done in the past is to carbon wrap the mirror with the same amount of layers I will be using in the new part and then take the mold from this.
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Carbon Tuner
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Carbon Tuner
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Well I decided to test the gel coat.I bought this paint sprayer in fear that my big 20oz. one would be to much. I started with the volume knob the whole way down and that was gonna take too long in my opinion so I had creeped my way to full pressure. This stuff is like gel, kinda hard for the sprayer. Still It seemed t slowly build. I got about 70 grams on a 6in. by 16in area.
 - High volume, low pressure (HVLP) material transfer
- Designed for detail painting
- Gravity feed
- 5.3 oz. cup
- Regulator available separately *********** I got the regulator toooooo
- Stainless steel nozzle and needle
- Flow rate: 40cc per minute
- Minimum transfer efficiency: 65%
Required pressure: 43 PSI | Average air consumption: 3.2 to 5.6 CFM | Nozzle size: 0.8 mm
I think that purple gun mentioned in earlier post would be a total POS do not get it for this gel unless you do small parts like cell phone cases.
Here's what the Mold looked like after I was done.

Let me ask this, is anyone getting a smooth finish right outta the gun? is this smooth enough to do a decent infusion? should I be sanding this?
Just trying to get into this stuff but devil is in the details...
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Matt (Staff)
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Hi Carbon Tuner,
It looks like it's gone down evenly but it does look a bit 'dimply'. I think what you'll find if you infuse over this surface is that the carbon will look consistant but it will have a slightly strange appearance caused by the dimpled surface of your gelcoat. If you wet-laid carbon over it (not that many on this forum would) then it would look perfect because, without the vacuum pressure forcing the carbon hard against the dimpled gelcoat, the carbon would take a straighter line and resin would fill in the dimples. Under vac pressure however the carbon will follow that exact surface and might be left with a very slight pattern to it.
To improve the flatness out of the gun, it actually helps to put slightly more gelcoat down and put it down faster as well - this allows it to self-level a little more. Also, the clarity of the GC50 is very good and so being a little thicker on the gel is not too much of a concern. Like all clear gels if you go too thick then you'll get a slight milkyness but that would need to be pretty thick with the GC50 before it started to do this and in general, a thicker gel will provide more UV protection and more to polish into in the event of a scratch.
I'm looking forward to seeing how the part comes out.
--Matt
Matt Statham Easy Composites / Carbon Mods - Technical Sales
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Carbon Tuner
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Well The Part came out like you guessed, looks nice but fiber is dimpled.
I decided to try again with a higher volume gun, same issue. Then as a last ditch effort I tried a brush. GOOOD luck getting a smooth coat with a brush "better by the best darn brush in the store too".
I am thinking the problem is its not going on nearly thick enough. My paint sprayers have a way smaller nozzle, not like the 6mm nozzle on the cup gun on the easy composites site.
Guess I am at a stand still tell I get this gun, some cups and might as well pick up that easylease.I did have a couple questions, #1. do I have to order these cups for the gun from you? Not that I dont love easy composites but I dont want to import paper cups from another country if I dont have to #2. Can this gelcoat be sanded to smooth out, same process 500, 1000, 1200, polish???#3. How do I give the piece I made its final glaze? Should I just hit it with a light cut compund, or start with full cut and work all three steps back?
Thanks for all the help I Feel like I am very close to perfect parts!!!!
If Brute Force Isn''''t working your not using enough...
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