The thing you could do is use easypreg finishing layer behind that plain weave to add some resin rich fabric to maybe get a better finish and less pinholes

Matthieu Libeert
Founder MAT2 Composites X Sports
website: www.mat2composites.com

 

i have a crazy idea let me know if this would work.. well i live in tropical country of costa rica and right now its summer time... how about i throw the bag on a peace of breather..  and put in on the roof top temps here get 80f but the sun is really hot sometimes... would that work... or is the sun too much... i can throw on roof top all day then cook.. meanwhile i figure out this cardboard oven out i can build a bike but electrical is my weack point i do have an air heater with built in temostat but if you saying that fan needs to be running thats where ill have to find out someone to make this for me... any pictures of yours? and an ebay list ill purchase everything and then figure it out

Haha..... the sun might just do it..... 

I will sort something a little more specific and try and give you a better description of the heater and fan.... I use MDF for the box not card...lol.. 

well for the ones watching and wondering i will be making another test today... this time with something flatter like a side fairing and its very sunny today so i will throw it on the roof top all day then stick it in the oven at 76c is the minimum kitchen ovens give lets see how it goes.. in this test i will also put a bit of peel ply on flange area under the carbon... stay tuned mean while thats taking a suntan im going to start the box oven fabrication

ok im running a second test on a second vac pump in my kitchen oven... this time i put the mold inside a carboard box that was filled with breather clotch and i place my wire tx term tip on the bottom side of the mold where it receives the heat and finaly got a stable  51.7

Ramping up is not just increasing the temp by 20 degrees, it is linear increase of temperature, controlled at 2 degrees/min for example. You should build or buy a purpose built oven with a temperature controller. Also, you will need the correct out of autoclave pre-pregs, otherwise you will never get pinhole free parts outside of an autoclave.

cheers,

Good luck

ok after cooking for 8 hours at 60C then 1 hour at 110 here is the results i can count about 5-6 pin holes only compared to a million on my other fast cooking parts apart from the voids where clearly this is autoclave fabric i thought id test with this useless fabric to me and the key to getting less pinholes everytime is... cooking low temp for long time and adding peel ply under the first layer on the flange area... the pin holes are on the side where no peel ply was placed

looking better... Once you get a part that works you need to do it about 3 times to make sure you are getting consistant results.. That part is a nice easy one and should give good results due to being flat. More complex shapes will possibly still have quite a few pinholes but if you can get a good result here on the basic shape it is a start... 

As pointed out ramping up is about getting up to a specific temperature at a specific speed. You can get to say 45 degrees and hold it for an hour then go up to 65 degrees but you need to get up to those temperatures without going up too fast.. VTF say you should go up to 60 degrees and dwell for an hour before going up to the final curing temperature they recommend on their spec sheets. each material is a little different but how you control the temp is the same. Dont start your timing for your cure cycle from the moment you put it in the oven start your timing when you hit the first temperature point you want to achieve. If they say 16 hours at 65 degrees time from when you get to 65 degrees... if they say 2 hours at 120 then time from 120 degrees.. It will ensure your parts are not undercured.. 

You will see a difference with an out of autoclave material... You might not get the results you expect or want the first time you use it but you should have an idea of what you need to do to make it work better quite quickly... 

def cooking low temp is the trick compared to the other horrible fast cooked parts i say its not so bad for using the wrong material