I’m looking for any tips for infusing in cold temperatures. I recently did a wing and the infusion almost stopped half way through. (My shop is about 64 inside) Luckily they were in the oven so I just turned it on, the molds and resin warmed up and it continued the infusion like normal. Problem now is I have to do a hood that is too large to fit in the oven. I was thinking of getting some electric blankets under the mold and a heating pad under the tub of resin. Other then that I don’t know. Any input?
What size of part are you looking at? Is this a one off or your production solution? Heat lamps can work and may be just enough depending on tool mass and material, etc. Could also use a homemade oven, all depends on your targets.
64F isn’t very low luckily and bringing up to 77F is likely to do the job (resin dependent)
If you cant get things heated for some reason you could use the lowest viscosity resin you can find, and the highest permeability you can get in your stack.
Get a box or make a box out of cardboard, stick the plug in there and put a small heater blowing not directly on the plug.
64 degrees isn’t that cold but cold enough to effect some epoxy since that stuffs sensitive.
Don’t forget to slightly heat up your mixing containers as well. And when I say heat I say warm really.
Can only second. There is no substitute for temperature. Get yourself a heated area, no matter how small.
Not sure I’d do this, but I’ve seen some people heat the resin. One person I know uses the microwave… does make it flow better but if it cools off on a cold mold then whats the point.
Couldn’t you also add more input lines to allow the resin to infuse over a larger area? Or use convergent flow to allow the perimeter to flow the resin in, again with multiple inputs on the perimeter?
I wouldn’t use a microwave… Typically warming the resin can only go so far until things start to kick to early.
It does help that it degasses easier though.
Do not try infusions at cold temperatures, resin will not flow.
I have a question about this.
Always higher temperature helps to infuse a larger area?
I ask because with a higher temperature of resin you infuse faster, but also going to gel before and you’ll have less time to infuse. Besides normally I cool my container resin input, to make resin arrives to the mold, with bigger pot life possible, Is this a good idea?
Regards
There is no substitute for heat. I run my shop at 23 deg celsius. But it is critical to have your mould and resin up to temperature before starting. A large cardboard box would do the trick for a car hood. Cardboard is a great insulator. Get yourself a cheap infrared thermometer to measure mould and resin temps. You don’t want to get them too hot.
Thanks for the replies guys. Like stated, I don’t want to just heat the resin cause as it flows across the mould, it will cool and viscosity will go up as well as over heating can cause it to kick early. Thus the need for keeping the mould and resin warm through the whole process. I like the makeshift idea of a large box. I will be making a hood for an E46 BMW so its a rather large part and figure the infusion should be about an hour. I attached pictures of an E46 roof I did in October/November and remember it being cooler out and the infusion almost didn’t finish.
Forgot the pictures.
What is your infusion strategy? Outside in, or inside out?
inside out. I put the inlet right in the center of the part and pull vacuum from all 4 corners.