By nosmos - 5/11/2015 3:08:18 PM
Hello everyone, thanks in for taking the time to read this, as I really need the help.I have tried twice now to make this part and both times I get the same problem. I am using the ec pre preg starter kit, and by all accounts it has had nothing but good reviews. There for I am sure I am doing something wrong. I am forming a profile 4.5mm thick on a bent ally sheet. I am getting a lot of resin flash, and lots of what I presume is what you refer to on here as pin holes. Although they are bigger than pin holes. I cured the first attempt in my kitchen oven at 100 degree c, and the second attempt at 85, just in case the oven was actually hotter than it said. Both cured ok except this problem. I am having trouble sealing the bag and have no way at the moment to keep the vacuum pump attached. If I am loosing the vacuum slowly, could this cause the problems I'm having? any help gratefully received. |
By ChrisR - 6/23/2015 11:55:49 AM
Sammymatik, you are right in everything you say from your experience (and from the sounds of it, rather extensive) I've had no difference in results (in my experience) by not running the pump all the time therefore saving the leckly bill  and although I do primarily make structural parts I'm not really after the extra few % of strength as deflection control is my primary concern.
but with no offence intended to the original poster, he is inexperienced with the material, running before you can walk and all that. With all things, you need to learn the basics, typical way of doing things and the rules, once you understand this in depth you can break the rules and go off piste. You wouldn't learn about quantum mechanics without knowing first learning basic physics first and working up. There is one thing I do disagree with but that depends on the pump i suppose, if you use the EC pump then you shouldn't run it with any sort of a leak as it will spew oil vapour into the air, contaminate any surface (or fabric) it falls on, overheat, use up the oil & burn out. (and Sammymatik, just so you know you're not just talking to a keyboard numpty, I first started working with composites (repairing boats) 20+ yrs ago, I'm a Structural Engineer did my MSc on structural connections in composites, designed a couple concept stage composite bridges, used composite sections in a few structures and have built my own workshop/small factory for producing the parts I design & watersports equipment to name but a few things!)
|
|