I think I am ready to move forward, suggestions?

General Composites Discussions Equipment Talk
#1

Whats up everyone, I have been around this forum and seriously, there are so many great minds here and I enjoy being part of the community. I started last year making some composites plates, just flat, and non vacuum infused, however I want to start making parts with actual shape instead of flat panels now that I have learned a bit about the baby steps more or less of composites.

I have seen some setups, youtube videos, and also some suggestions here but I wanted to make my own thread to more or less get some guidance from the masters. The parts I plan to make will probably be no bigger than 2sq feet, and if I decide to get a little more eager nothing longer than the chin spoiler for a front bumper.

Of course, I need some new equiptment for this these tasks, as well as to make the molds themselves.

Q1: For the size of the jobs, for my first pump, would something like this be sufficient?
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=98076

It seems well priced for the middle grade model that harbor freight is selling, but since this is my first, not sure if it has the power that I will need for vacuum infusion.

Q2: Is there any place you can send me, or show me how one would get a vacuum connector that mates up to these pumps, or is it pretty much going to home depot and matching a brass fitting up etc and attaching it to a hose?

Q3: Making the mold, I understand the basic process, however I am at a loss when it comes to material use. From what I have seen is generally you lay the part down on a surface, it then gets sprayed with generally a wax film, ontop of that is generally a film which is colored(I assume so you can see if you are missing any spots), after that is dry, applying fiberglass/resin to more or less make a shell which is durable. What exact materials are being used for such a thing, and can they be applied by brush, or have to be sprayed? (links to actual products would be awesome, but keep in mind this is my first vacuum infusion setup so the most expensive material is probably not a good idea for me)

Q4: Pressure pots, is the main objective of these to prevent damage to the vacuum pump incase the resin makes it through the mold and starts traveling through the tube heading towards the vacuum? I assume that is what they are for, if I am wrong I apologize in advance.

Q5: The parts I will be making will be either 100% carbon, or carbon for the face, and fiberglass backed, suggestions on resin? Right now I have gotten used to a 1:1 mixture doing everything by hand which has given me plenty of play time, but I assume for this type of work its more of a larger portion of resin and smaller amount of curing agent from what I have been reading? Any decent priced brands/types?

I first and foremost want to thank anyone who can help me answer my questions before I begin, I am doing this mainly because of my love of composites and wish I had gotten into it earlier. Thank you everyone!!

#2

Any suggestions guys?

I think I am going to try and build a mold first of a part or two and then pick up my vacuum pump/pressurepot/tubing/resin etc.

*What tooling gel do you guys suggest that I could brush on, and also any preferences on fiberglass resin, or would the Bondo/Napa brand fair well for a mold?

http://www.uscomposites.com/polyesters.html

Suggest the 404 Tooling Polyester Resin-Isophthalic or the Orange Tooling Gelcoat?

Both will be applied on by brush.

#3

I cant answer all your questions but I can some.

Mold making is pretty simple really, the hardest part is flanging your plug… and you must flange it to make a mold correctly. Mold material can be just VER with CSM. I would recommend tooling gelcoat over std, it has high scuff resistance and is generally tougher and will last longer. Apply multiple coats of your gelcoat spaced at least a couple hours apart, depending on if your planning to wetsand/glaze/buff/etc. 6-7 tops and is fine to brush, I do it all the time, just make sure you leave plenty of cure time. Carnuba release wax can be bought in a spray pack, but is often just in a tin where you rub in on in a circular motion, wait 5 minutes or so till is partially dries and rub it off. Wax goes on first. For a plug layup for mold construction you should always use PVA (Polyvinyl Alcohol) ontop of the wax, this is the coloured release agent you mentioned. It creates a film over your plug that physically stops any product actually touching your plug (and causing possible reactions). I recommend spray because you can get a nice smooth finish for your mould. You can also rub it in with a cloth like wax, but it can get pretty messy and you can rip your previous layers, but its def possible, just go easy after the first few coats. You can pile the PVA on. But I usually stop at around 7-8.

I dont know much about the exotic cloths and infusion, but PER is not the go with carbon, go with epoxy and a slow hardener or a VER product. This way you get the crystal clear surface coat to show off your carbon, you need the extra cure time if your infusing anyway, I would recommend an epoxy infusion purpose resin.

I get my supplies from and Aussie company but ive only heard good things about UScomposites and Tap Plastics.

Also I feel you should rethink the infusion setup. To me infusion is more the mas production side of things then the home fiberglasser, there is allot of consumables involved. I think you should start with hand wet out and a simple vac bag setup to start. You can always add the infusion setup later.

#4

Thanks you so much! I agree with the infusion process, since my first few molds are going to be pretty tiny I think I will try just the simple vac bag setup as suggested. I found a 4cfm Robinair locally used for $100, however if it doesn’t look decent when I see it I may pick up the Harborfreight 2.5CFM unit.

Thank you for all the help so far

#5

Welcome!

Since this is a volunteer staff…it is best to ask 1x question at a time. I didn’t think I had ADHD but reading thru a long post with many questions…

To many beginners think they need to start off with VIP, but you need to learn the basics first like open mold, hand lay up.

#6

LOL thank you for the welcoming, I just figured instead of making 5 individual threads compile it all into one, but I see how it could have been a hard read lol

#7

Going to buy this pump today as I have a good coupon to get it at 15% off:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=98076

My goal is to perfect my flat sheets using a vacuum bagging technique to get rid of the air bubbles/pockets used when just hand laying it.

Besides the pump, what should I get for connections/hoses/regulators and is a pressure pot a definite?

I need a little bit of help in that department, but I already know I need to order some bagging tape, bagging plastic, and breather bleeder along with some of the preforated plastic to let the resin flow through to the breather bleeder.

Also what is the best Hg for vacuum bagging as far as a limit that I should stay within? I know I will have to set this with the regulator/vacuum guage setup I will have to make

#8

Just obtained a rotary compressor from a big fridge for nix. I was skeptical about the performance of this old girl that was going out, but it pulls over 29" on the bag no trouble at all! Cost nothing, resin fumes will never kill it, and even if they do, who cares :smiley:

#9

lol Can’t beat free!

Picked up the pump and also a pressure pot from Harbor Freight. Found out there is a local vacuum bag supplier in the area which is awesome, but the resin I will still be ordering locally along with most likely a few other items I didn’t see on their website. US Composites I have ordered from in the past and most likely will be using their Vinyl Ester resin as well as their Orange Tooling Gelcoat for when I make a couple molds of some small items I want to try to put under vacuum.

#10

2: for insusion, just look for something to permanently(ish) mount the pump to the pot. From the pot on to the bag, we here use a 3/8" HDPE tubing, that uses a compression fitting on the pot side, so you can take it off, and slap a new one in, in 30 seconds.
To the bag, we use the tube into the bag, and then sprial wrap, or omega channel. I THINK our wrap comes from Northern Fiberglass Sales, or Newport. I think ANY spiral wrap that wraps onto the size tube you have, will work.
I’m sure depending on the size, 1/4" tube would work fine as well. All connectors would be found at home despot, McMaster-Carr, or MSC. Even Harbor might have fittings.

if you want QUICK disconnect fittings, that is different…but for infusion, stick with plastic tube. It’s easy, effective, and no chance of messing it up with resin!

4: yes, for a resin trap. Stick a vac guage on the pot and a ball valve on the vacuum side. This way you can shut off the vacuum source, and check the gauge to see if there are leaks!!
Also, maybe grab soem plastic bucket liners so resin doesn’t collect in the pot…or maybe just plastic wrap.

#11

When I went to go pick up my stuff I had held at the store, they only had the pump, no pressure pot.

I also bought a 1/4 sleeve, so I can run yellow spiral compressor hosing to the pressure pot.

Is harbor freights pressure pot the best buy at $79.99 or anywhere else I should look? Trying to get a complete setup by next week to give vacuuming a whirl.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93119

Going to need a vacuum guage too for whichever pressure pot, as I am sure they are all rated in PSI etc

#12

HF is the best deal on them. I have 2x of them…one for VIP and the other for vacuum degassing.

Is Fast would get off his back side and take a trip down to a surplus yard I told him about in his town…he’d be selling vacuum pumps and gauges on here cheaply.

I just wish I could make a trip out to Phx.! :rolleyes:

#13

hehe^

I just picked up a 1/4 compression fitting and also a barb fitting just incase to attach to the pressure pot, as well as some 3/8 OD, 1/4 ID Polyethylene tubing to run from the pot to the vacuum bag as well.

I have to make an order through US Composites (love that e-store), but going to take a look at Jamestown distributors website as well to compare some pricing on vacuum bagging materials, as a lot of people suggested them for Airtech brand supplies, and I am actually right around the corner from their store so I could save shipping charges on whatever I buy.

Hopefully I will be vacuum bagging and infusing soon and show you guys some of the flat plates I will be making, after that is perfected I will make a mold and give that a whirl.

I do have a question though, say for example I get everything set up, vacuum pump turned on. At that point I have read a lot that you want to keep constant vacuum for the curing of the part (which makes sense), however are you actually running your pumps the whole time, running a regulator etc? Just common sense tells me if you keep pulling vacuum at a non stop rate with no leaks, the bag is capable of coming off the tape or possible tearing/breaking.

What do you run to regulate the amount of vacuum for the curing period that the pump is running? Just a normal compressor regulator with a vacuum gauge on it? This is the only thing I am confused at right now.

#14

Werks…what’s the name again of that surplus store? :smiley: Werks is right i need to “get off my duff” and take a trip there. My income is lowsy right now and could use a little bump up.

I also have the $79 Harbor Freight catch pot. I bought all my brass fittings from Lowes and HomeDepot plumbing departments.

You may not find the exact thread pitch fitting for your vacuum pump but i think 1/2" pipe thread will work if you use a lot of teflon plumbers tape on the fitting. This is what I did with two pumps and they held vacuum good. For all the other fittings I used SAE pipe thread fittings and the plastic hose.

#15

^^I actually threaded a 1/4 female connector to my pump, with thread tape of course and seemed pretty tight on one of the ports (larger of the two), I then threaded my compressor hose into that same female connector on the other end which will be run to my harbor freight pressure pot…that I just got for a little under $35 shipped!! Its a central pneumatic harbor freight house brand one.
I wish I could get more for you guys at that price but it was an auction that I had my eye on after not being able to pick up one today in the store.

Still researching on how you guys regulate your vacuum pressure, and have seen some postings about using a device called a MAC valve, but thats a little more indepth than I would really like to go with it for the first time around, any suggestions?

#16

This gauge looks ok:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:VRI&item=220324032975

#17

Saw that one the other day will pick one up soon. I was contemplating running a used Autometer gauge my friend has an is not using but would rather go with one that I do not have to mount somewhere haha :stuck_out_tongue:

#18

Most vacuum pumps come with flare fittings. Use flare to compression or NPT adapters.

No need to regulate vacuum. Generally a full vacuum is desired. The only time I specify less is for debulking prepreg, and my techs have different colored hoses that only pull 10".

#19

I bought one yesterday. :slight_smile: I’m watching your thread with great interest as I am in a similar position where I feel the need to take the next step to vac bagging and infusion, I’m following some posts on here from some guys in the UK who made their own pressure pots/seperators from drainage pipe and some fittings, hence the guage. :wink:

#20

Well I am glad that you are here then, we can learn from eachother as well as the much more experienced here, nevermind take what we learn and help others in this community here at Werksberg. I am just thankful that people are giving me some tips and tricks as people generally go to me for that type of stuff computer wise as that is my profession. (incase anyone here ever needs a hand with computer related things I can give some insight) :0)