Hey all, I’m new here and relatively new to composites. I’ve done a little bit of vacuum infusion with some good instruction and was quite successful first time out. However, the materials I used were ones off his shelf and really incorrect for my application. Instead of an infusion polyester I want to use a low viscosity epoxy. I haven’t infused any epoxy yet, and since it sets up much more gradually than polyester resins my first question is this. At what point during the initial cure do you know when to de-bag the part? Also, has anyone had any experience with Film Technology’s bagging material? Supposedly, It has built in flow channels eliminating the need for flow media. Does it work? Last question…Is there a peel ply that is more conformable than the standard nylon material? Thanks for any help!
well, really the only question I can answer is the peel ply. i am using VER resin 99% of the time and I have been buying some MAJORlY strechy 100% polyester from walmart for $1 a yard. You have to take it off when the part sets or it will become part of the piece
Never used the bagging material, but i would hope they work. Try to get a sample roll, and test it out vs. with flow media.
Get an AirTech (airtechonline.com) catalog. They are a good supplier, along with Nothern Fiberglass Supply. They might be able to help you on which peel ply is more conformable. You can also use several cut pieces instead of one large one, depending on your mold.
As for the resin, read the tech sheet for the resin you buy. It should have gel and cure times listed, along with hopfully if you need to post cure at a high temp, and whether to do that freestanding or under vacuum. I’ve had parts sit for 24hr after infusing, unbagged when hard, and post cured. During the post cure, it softened the resin, deforming the part. Nowadays, we let that resin sit for 2-3 days. Always check with the manufacturer about product specs/MSDS before use!
i cant find my camera charger so when i get my new one in I will take pics. You can use any 100% polyester fabric. My walmart has a $1 rack that i find all my peel ply in. just stick with the light colors! It is a little thick but having a strechy peel ply is amazing!
i does for me cause it is so strechy, for exaple if I had 6 iches of fabric length wise I can strech it to about a ft and a half that is how strechy it is. Plus I put it in strips where and also make cuts with a razor in problem areas
Thanks for the replys, I much appreciate it. I sometimes find my search through the myriad of processes and materials somewhat daunting, but none the less very fascinating and challenging. I am a one man shop that has chosen to break the mold in my profession and employ composites as a replacement for natural materials. Briefly explained, I build handmade saddle trees, which is the framework within a western saddle(talk’in equine stuff here). Traditionally, rawhide(the skin of a cow ,bull, or steer) sewn around this wooden framework, is the strength covering for this structure. Although rawhide offers great strength characteristics, I have found many more benefits in the world of man made composites. After studying what I could about vacuum infusion, I decided this was by far and away the process of choice for the application technique. Although what I do is far removed from the world of aerospace and motorsports, composites will play an ever increasing roll in many traditional arts. As you can see in the pics attached, this is an overlay process. Any suggestions on achieving a nice even finish(textured or smooth)would be helpfull slso.
The only way you will achieve a perfect surface like that, is using a multi-part mold for a first surface finish. Use a silicone rubber skin made from a finished part (which leaves infusing out of the question, and leads into the thermoplastic realm of composites). Or build up a layer of resin on the outside (paint/spray on), and then sand smooth. But yes, for strength glass/CF/etc will help greatly. Might save some weight too, however leather being a soft and resilient material might be what people want anyway. Riding on a hard epoxy surface might sick, vs. a leather seat with some cushion.
Maybe if the whole part was composite, maybe with foamcore, you will save enough weight to add a foam seat for the rider?
ps: if you want to get modern, AND natural, you can always use soy based resins (lookup: richard wool, Uni. of Delaware), and natural fibers like lute (jute?), and hemp. There is alot of work going into making 100% non-synthetic composites!
anyways.
