Vacuum Infusion

General Composites Discussions Composites Talk
#1

I have tried my first mold and it came out sucessful! There were some touch up spots but nothing that effected the actual finished part. I have learned some things to imporove on for my next mold.

My next step is infusion and I have some basic questions. I did try to search and couldn’t find excately what I am looking for.

Below I have a list of parts:

Clear Gel coat-we want to watch the resin as it seeps into the fiberglass
2X2 twill cloth 8.5 oz. seems thick. (US C)
Peal ply release fabric (US C)
Flow media.
Spiral wrap
Breather cloth (US C)
Sealant tape (US C)
700 Vinyl ester resin from (US C)
3M #77 spray adhesive (US C)
Nylon bagging film (US C)
Tees for vacuum and resin

Most of the parts I am going to try to acquire from US Composites.

My first question is where do you guys think I should buy the remaining material, gel coat, flow media, spiral wrap, etc? Am I missing anything as far as materials?

Next question is I am unsure of how many layers of fiberglass is necessary. I am thinking of using the 8.5 oz and my orginal part is 1/8 of an inch thick. How many layers would it take to get around 1/8".

Thanks guys, I know these are really basic newbie questions but anything can help me at this point!

I have attached pictures of the mold and the vacuum pump




#2

Do you have any diagrams or writeups of how you have your vacuum system set up? I was thinking of doing something like that but your setup looks a lot cleaner than others that I’ve come across.

#3

Sure do link attached.
http://www.joewoodworker.com/veneering/EVS/concept.htm

Mark44

#4

Awesome…thanks!

#5

http://www.compositeforum.werksberg.com/showthread.php?t=2588

#6

Your vacuum resevior set up looks neat and clean. For infusion you will need to have a resevior with the vacuum fittings on the top, not sides preferably, and space your fittings far enough apart that resin doesn’t just get pulled from the entrance fitting to the exit fitting if that makes sense.

Flow Medium get the red mesh, Airtech makes it and it’s #60 RED.

For cheap fittings go to Lowes or HomeDepot in the sprinkler/bubbler section. There are 3 way T’s that are 1/2" size… the 3/8 vacuum and resin lines fit nicely right inside the T’s… cost .60 to .99 cents each. For the resin and vacuum hoses go to Lowes and get the white-clear colored polyethelene hose that is 1/4"I.D. and 3/8" O.D. That line will hook nicely onto most fittings and sprial wrap. Some people say use a larger I.D. hose than 1/4" but i’m just saying what i have been using. Although I do tend to think a 3/8" I.D vacuum hose would work better, same with the resin inlet. That’s just a guess on my part.

Peel Ply… I buy mine from Werksberg for around $15 for two linear yards and he usually gives you like 2.5 yards, excellent price imho. I recently bought 6 yards from him. It’s a tight weave nylon peel ply that releases easy and seems to work for vartm. The texture it leaves behind is very minimal and if you clearcoat over it you would probably never know it was textured.

Bag tape… I personally would recommend the yellow AT 200 I think it is. It’s yellow for sure and super sticky. less chance for leaks. Once you get really good at bagging lay ups then go to a less expensive bag tape … again just my opinion.

I’m not sure if Polyester Gel Coat and Vinylester resin are compatible… check with both manufacturers to make sure.

the rest of your supplies sounds like a fine place to buy them from.

#7

Mark, If you don’t mind me asking - how much $ did that entire vacuum set up cost you, minus the pump cost? How much hg can you pull with it? How can i modify the unit/assembly so that one of the vacuum canisters is sitting upright instead of horizontal?

I’d like to build one someday.

#8

I see you have found the light also. Thats where I found my first (and only) vacuum setup. Still working after 3 years (of light duty).

#9

Not counting the PVC or ABS piping & fittings these are the prices for the other fittings etc.

MAC Valve $25.20
Vacuum switch $24.50
Relay $20.75
Dampener $10.90
Breather fitting (for MAC valve) $2.50
Pump Filter $14.95
Check Valve $12.95
Total: Approx. $115 w/shipping

I’m using a Robinair and can pull (if what my guages are telling me) 30" vac. It took a little fiddling to set the vac switch to shut off at that level. Mine drops a full 2" before it kicks back in. Works sweet and you don’t have to sit there and babysit it or let it run constantly (noise etc.).

#10

That’s pretty much why I would like one of these set ups… less noise and less wear on the vacuum pump.

I wonder if you can “set” the thing so it can lose 5" of vacuum then kick back on? I’m just thinking that way maybe the pump would not have to operate as often.

#11

Thats exactly how a MAC valve works. My pump is set to turn off at 27.5 hg. If/when I loose vacuum it kicks back on after I loose about 5 hg.

Most vacuum regulators work this way. Some have much larger increments between max/min settings.

#12

Awesome. Now I definately have a reason to hit up that surplus store Werksberg told me about.

I want to build that thing and a cnc router if I can find the time and funds for the router.

#13

The MAC Valve only opens & closes the vacuum. A vacuum switch is required to monitor comparative vacuum & control the MAC valve. Mechanical controllers are simple but are not as accurate as a digital vacuum switch. You can expect at least a 5% variance with a mechanical controller while a digital switch is repeatable within .2% and they are more durable than a mechanical controller.

#14

The pump came from a collage size fridge that was out of service do to an ice pick I did have to purchase the PVC pipe vacuum controller and mac valve that I got from Joe wood worker, I couldn’t find any cheaper anywhere else, I had all the fittings and lines so that was free but I did have to purchase the wood and brackets.

I have put the system under vacuum for 24 hours and have only lost 1” if that so it seems to be sealed up quite well.

The resin trap I plan on mounting vertical to keep the resin from entering the pump system, I also plan on making a larger trap out of 3 or 4” PVC in the future.

Now I just need to purchase some materials for my first infusion when I have the cash.

Thanks for everyone’s help this forum has been great!

Mark44

#15

Hello.
On your form I can see mistakes which rose at the production.

First
Premature deforming.