so I am doing some carbon fiber overlays and have come across an issue

my epoxy doesnt harden it will get real tacky but not sandable I am pretty shure I got a bad batch of resin

so I am wondering is there any way to fix this issue? I have allready put lots of time into these peices

all I want is the resin to harden

 

usually if your resin doesn't harden its because you didn't put the right ratio of hardener in it. Your stuff is probably ruined but you can dry applying hardener right on it. Bummer

 

do you need it to cure at an elevated temperature?

I'm pretty sure your part is no good at this point.

 

yeah I dont really know about the whole putting hardener directly on the peice.

sounds a bit too much for me.

the resin/hardener ratio was right on the money. I know this because I use a digital scale everytime I mix any up.

I figure it could be because of my old resin I bought annother container of it new and started annother peice I should know what was up for shure tommorow.

however I still want to save these peicees real bad I have 2 rather complicated parts that I have put about 20 hours into all together.


can I put it in a furnace room possibly? will that make it harden eventually? can I sand the crap out of it and mix up a hot batch of resin (extra hardener) and pray that it works?


any knowledgeable ideas would be greatly appreciated!!!!!!!!!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RTErnie &raquo;</TD></TR><TR><TD CLASS="quote">do you need it to cure at an elevated temperature?

I'm pretty sure your part is no good at this point. </TD></TR></TABLE>

I know that the optimal curing temperature for my resin is around 72 degrees farenheit.


it is a little colder but I shouldnt be having these issues whatsoever given the time span this has been going on for

 

We accelerate the cure time for epoxy in aerospace applications all the time with temperature. I would post the charts, but they are proprietary. We can basically put 30 days of curing into 8 hours at temperature and have the analytical tests to back it up.

What I would suggest is putting a 150 - 250 watt flood lamp about a foot or 18 inches away from a part of the lay up overnight. If that additional heat gets rid of the tackiness, you have your solution. Now scale it up. You could always rent an autoclave @ $2K/hr...

 

Did you think about heating the resin to a lower viscosity and basically bleeding it out?

Are you doing vartm? or open mold wet lay up?

 

I am just doing over lays open mold I guess you could call it though no mold is involved.

ill have to give it a whirl with a heat gun for now I suppose I doubt ill beable to get the resin to bleed out as it seems to be half cured permenatley..

I hope I can supprise myself and fix the problem if not I guess its heat gun and tearing off the fabric and waste all the time I have put into this thing.

I dont want to go that route but I think its nessecary

 

It is time at temperature, not just a high temperature for a short time. The reaction rate (polymerization) increases with temp, hence my recommendation of a light bulb that can be left on it for an extended period, like a day or two... I've fixed a number of my messes at home with soft heat for a longer period, at work, it is back in the autoclave.

 

right on well right now I am goint to bring the parts to my parents house and put them in the furnace room it gets nice and warm in there all day long