White spots inside of my Carbon Fiber Epoxy Laminate

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White spots inside of my Carbon Fiber Epoxy Laminate

Author	Message
tsombnik	t tsombnik posted 6 Years Ago HOT Post Details
t Group: Forum Members Posts: 6, Visits: 147	+x oekmont - 1/9/2018 1:08:09 PM still, there is a vacuum inside the mold, and the resin front is under vacuum. What kind of pump are you using? Are you using the same pump for the evacuation as for the degassing? What negative pressure do you reach? Ah okay, yes you are correct. We are using the same pump for evac and degassing. We reach a value up to 30 mbar remaining pressure
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oekmont	oekmont posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	what type of pump are you using? what do the specifications say how much pressure it can reach? 30mbar happens to be the boiling point of water at room temperature. If you got a moisture problem, the pressure stops at this point during evacuation. Because of this, I degas at least down to 6mbar, at wich the boiling point is at 0°C. And during infusion, I try to maintain a slightly higher pressure, around 6-7 mbar, to prevent further degassing.
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fibernoob	fibernoob posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 34, Visits: 134	+x tsombnik - 1/9/2018 7:21:08 AM +x fibernoob - 1/8/2018 11:58:06 PM Im not sure its your case... but I have had similar problems when I used too much (wax based) release agent and did not polish it into the mold. Hello fibernoob, we also used wax based release agent in the area of the sealing cord, so that we can use it again if resin reaches the sealing areas of the tool. So yeah, im pretty sure this can be the reason. We are going to clean the tool again and wont use the wax release agent anymore. If somebody has another idea though, please tell me Maybe it can help. Thank you for your help! Nik After getting some information, i discovered that wax based release agent has to be applied and thoroughly polished and left for some time for the solvents to evaporate and leave just a thin film of wax (invisible chemical barrier). Remember that your part will replicate the texture of your mold... if its smooth and well polished (shiny surface) with release agent it will come out perfect. In my case, I thought that the more release agent i would cover the part with ... the easier it would demold! That was my mistake. The part then showed similar white residues on many places. Check if those white spots have a similar greasy texture to make sure its release agent. You can use Water Based release agent (PVA) but it is not as easy to polish or spread uniformly. If the problem is not release agent related, it can be what the other comments are suggesting. There are valid points being made... Humidity , Resin Ratios etc. Good Luck !
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