Infusing in the dark...Bad and dumb idea

General Composites Discussions Composites Talk
#1

I had to get a part infused today, guy paid me already for it.

So I’m outside in on a dim-lite balcony trying to infuse this part and EVERYTHING is going wrong. Small bag leak, the flow medium moved and would not go back to where it should have been, even with no vacuum under the bag. The resin kicked in the cup while i was trying to fix that. So i cut the bag open inserted a new resin line and fresh resin, it only infused one of the two parts on the same mold…damn:mad: So i cut the bag open and insert a third resin line to the other part, i stick my line into the cup and holy cow man…i stuck it into a cup of water and it sucked a crap load of water into the mold and a little bit into my vacuum pump. I waisted about 20 ft of vinyl hose and about 10 ounces of resin, not to mention the bagging stuff and the laminate materials. I’m not very happy, but i’m starting to chill down now. I just turned the pump off, came inside and shut the door. Screw it. This is one messed up day…first my boss getting angry with me for stupid reasons and then this. Oh well, there’s always tomorrow.

No advice needed thanks, I just wanted to get that off my chest LOL.

#2

you might want to consider running your pump with the gas ballast open before running the pump for your next infusion. water/moisture is very bad for your pump and the gas ballast will help get it out

#3

been there, done that…

#4

Yep, did that already Hojo, but thanks for mentioning it. I’ll do it one more time before i run the pump next time.

I need to get a shop space. I’m gonna look for one by January 1st.

And you can bet I’ll be installing plenty of florescent lighting in that shop.

#5

I can make £60 for a pair of sidepanels that take me around 30 minutes to make using materials costing £1. I use contact moulding, poly resin and GRP.

Contact moulding does need a bit of practice to get right, but for small numbers of cosmetic motorcycle parts, I honestly cant see any easier/quicker production method.

Carbon parts can be easily made this way also, but ideally a caul plate is needed, and viscosity of resin adjusted to particular application.

For making cosmetic carbon we were using contact moulding, modified clear poly casting resin, highly polished moulds with caul plates, which resulted in 15 minute process time for smallish exhaust covers, which other than trimming needed little or no final finishing.

#6

classic, what you mean by contact moulding? a male and female mould pressed together? :slight_smile:

#7

Contact moulding is another name for hand lay up. We found that with just the right resin viscosity, using simple 2 part moulds, that perfect parts could be produced very reliably and quickly, and at minimal unit cost.

I seem to remember we did around 350 parts this way, the bulk of which went to a bike importer in Australia.

#8

I remember both spraying and infusing when the power goes out.
THats a panic attack to say the least

#9

oops, double posted. the cat stepped on the keyboard.

#10

haha, yeah I have thought about ’ oh no, what if my pump goes out while i’m infusing or vacuum bagging a mold’. I’m thinking of making a quick-disconnect vacuum hose and fitting for my pump, if it does stop working, then just switch over to a back up pump.

Lucky for me the power only goes out here about once a year.

That could really suck to be doing a large part or medium size part and loose power.

#11

If you have some sort of vacuum tank, rather than relying wholly on a pump, then unless you have a lot of vac leaks, any problems due to pump not working will be a lot less serious. Easy to make something like this out of an empty LPG cylinder…

#12

having a tank is also good to pick up any moisture and debre that may over time get sucked in. the vacuum we got has a 20 gallon tank on it

#13

20 gallon tank is probably a bit big for home workshops, but if you use an LPG cylinder, its easy to select the ideal size for your needs.

#14

ha, yea, a little big, but are vacuum pump is 10 HP, we run 3" piping through the shop. the vacuum pump is run by a computer

#15

I’d like some details on how you do that HoJo. I just burnt out a vacuum switch cause the startup amperage of my pump was too high. Rewiring with new switch and relay now. I’ll post details when it’s ready. It was only a $50 mistake.

#16

the pump we use is an industrial pump, 3 phase with built in reserve tank and pc. same vacuum that GKN aerospace uses, except they have the 40HP one. we have 3" pvc piping running through the shop with 2" pvc drop downs to mainifolds

#17

How does the computer control come into play? I have done some robotic stuff with CnC mills and can see how a solenoid or servo could control the on/off of the pump.

#18

it does a bunch of stuff like monitor running temp, total hours running, maintance stuff, timers, you can programe it to run on idle betweem certain amounts of vacuum, has a digital display. it probally does many other things too that I am un-aware of, its a pretty intense pump to see

#19

Computor control of your vacuum system is not going to prevent switches burning out, if the current they are handling is too high. Simply fitting a cheap switching relay, rated about 25% higher than pump start curreent draw will prevent switches getting damaged.