Large infusions, can it be done with small pot life epoxies?

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#1

I am trying to figure out what epoxy to get to fabricate an FSAE body and we want to do an infusion since our team members have experience with it. The body panels won’t be too large, but I am not sure if a pot life of even 60 minutes would be able to fully infuse it, so I was looking at resins with 120 minute pot lives but they are a little more rare and expensive with low viscosity. But I have been thinking, is there anything stopping me from either doing two feed lines and opening the second one half way through the part when the resin front reaches it, or just mixing several batches throughout the infusion and refilling the feed bucket? As the resin heats up, pouring new freshly mixed resin should cool it, but would it heat up again fairly quickly? For example, if I needed 3 gallons and I only mixed 1 gallon at a time, then when it gets low, I mix another gallon and pour it in, would that negate the smaller pot life?

Does anyone have a recommended infusion resin with up to 120 minute pot life for $150/gallon resin kit? We did an infusion with uscomposites medium hardener on a panel about 4 plies thick and 12" x 36" that just barely made it before the resin started heating up.

So, my main questions are, is it okay to mix several batches of a smaller pot life resin to accomplish a longer infusion, or should I get a resin with a longer pot life and only mix one batch? And which epoxy would you recommend for $150/gallon kit?

Thank you!

#2

Hahahahah! Your funny.

Of course, who doesn’t do that? Iff you need more add it, and use 4 bucktes, 29 inlets, switch some vacuum to inlets, reverse flow… Tons of good things you can try. Experiment!

#3

Oh, and can’t you find resin cheaper than 150 each? How much? Buy in bulk! =-)

#4

I have 140minutes resin and it always last for to short for me on 1.2x1.2 meter panels , especially Im degassing like 10minutes.

#5

You should be able to infuse a 12"x36" long part in ~10 minutes if your flow media is set up correctly.

Contact www.prosetepoxy.com and use their INF114 system with either their 211 medium or 212 slow hardener. You can buy 1 gallon kits directly from them for less than 150. shipping will add to it, but in volume (5 gallons+) it starts to fall below 100/gallon, with shipping.

Your idea of augmenting your infusion pot is spot on. Only problem with this is that you need another vacuum pump for your degassing chamber. Alternatively, you could clamp off your vacuum draw line on the system and use the same pump, but that introduces other problems. The built up heat in the left over mixed resin at the bottom of your pot shouldn’t be an issue if you augment it only when it’s low enough. You will of course lose a small amount of pot life as the entire cup now has a marginally higher overall starting temperature than the first one, but it’s essentially a negligible amount.

Sammymatik - just for the record: multipoint/staggered injection infusions are very common on large pieces.

#6

Here’s a video that might help you out if you decide to try a multi point infusion

https://www.youtube.com/watch?v=x42LwtuU5fQ

#7

Thanks for the video! It looks like the second feed line would introduce some porosity in to the part in the region of the hose between the clamp and the resin. At the same time though, could long infusions like that potentially stall out without a second feed line? When do you go with a second feed line versus just refilling a single feed bucket?

I think our largest parts would only be about half the size of that anyways, so I think I am pretty confident we could just do it with one bucket. Thank you everyone!

#8

Just depends on if your resin has the proper viscosity to wet the part out before the resin starts to gel in the part, or, more likely, the resin in you first feed pot starts to kick. The later can be fixed by batch mixing resin.

The second feed line can either be primed, so the entire hose behind your clamp is filled with resin and then everything in front of it, under vacuum, is evacuated; this will result in a fairly good wet out, or the second line can start to infuse before the resin front hits the 2nd lines spiral. That takes a bit more practice because you have to make sure any air between the second and first front can escape, which requires some planning and good timing.

Anyways, for the size of your part, I really don’t think you need two infusion lines. You should be able to infuse a 3x1 foot part more than quickly enough with the right flow media (eg, properly placed infusion mesh)

#9

Just for the record, the setup in that video I linked to isn’t exactly perfect. His vacuum draw spiral wrap is positioned immediately above his infusion mesh at the brake zone which isn’t ideal at all and really just leads to waste. Search the forums for ‘brake zone’ for more info

#10

look at PTM&W 2712 Part B - 70 miuntes; Part B1 - 122 minutes
Part B2 - 175 minutes; Part B3 - 40 minutes
I have been paying about $116.00 for gal kt.
fast delivery UPS

I switched from ProSet years ago

#11

Can I ask why? What did you not like about the proset system, and in what ways do you consider your current system to be better than the proset system?

#12

product support

#13

hi Tom

May I ask if you experience “spot” with Proset Infusion ?

#14

Once again I am shocked by the prices you guys pay. Here on an island the size of Colorado at the bottom of the world, 4 litres of an infusion resin is about $NZ100.

#15

HSU I have no clue what spot is

I’m not very educated sorry
PM me if you can. I will be gone for a few days at the racetrack

#16

I just did a usd to nzd conversion and your dollar is about .17 cents more than ours, so 4 liters for the equivalent of $116.60 USD :eek:

Keep that deal! Amazing.

#17

100 nzd is about 85 usd :stuck_out_tongue:

For 4 liters (1.05 us gallons) that is a very impressive price, especially if that’s per four liters and not in a larger volume kit. I can only come close to that if I’m buying a 15+ gallon kit directly from the manufacturer.

what resin system are you using? is it a local product?

oh well, at least computer products aren’t twice as expensive over here :smiley:

#18

The dollar is quite good at the moment.

West System Z105 is $NZ160 for 4l.

The cheaper is locally made, that price is derived from 20L and is cheaper still when you buy 200L at a time.

#19

How does the proset and others compare to adtech 820? Currently my 5 gallon pale if adtech is running low and I’m making a larger than normal part “about 3 feet by 2 feet” and my resin has a tendency to kick in the pot. I really just need a second pump after reading this thread though to degas in batches.

#20

Degass before you add hardener and a short time after.