Infusion: Is pulling resin down the laminate a bad idea?

[ahender]

Hi:

I have a resin infusion question.

I am in the process of infusing a male canoe mold.

I understand that the resin bucket needs to be lower than the part.

Am I wrong in assuming that I can place the resin infusion line at the top of my male mold with the resin flowing downward?

thanks...alan

[KnottyBuoyz]

Possible. Unusual I believe. You'll need multiple vacuum lines that you can individually shut off when the resin reaches them or you'll likely end up filling up your catch pot with resin. Conventional setup would be to feed the resin in around the bottom with a single (2 or 3 is ok too) vacuum exit on the top edge. When the part is about 3/4 infused you'd shut off the resin feed and let the vacuum continue to distribute the resin through your whole layup. This way you'll waste no resin and end up with a better (resin/fibre) ratio in your layup.

[ahender]

Thanks Rick.

I have never read about shutting off the resin line at the 3/4 point.

I think I have read every article ever posted on the Internet, but have never seen that.

Are there any caveats as to when that can't be done -- like a less than desirable vacuum (say ~20") or other variables.

I learned the hard way yesterday on using a HVAC vacuum pump, as opposed to a heavier duty "continuous use" model.

In my case both my primary and secondary pumps failed after 2 hours of continuous use due to heat.

I pretty much had to stay with the project all afternoon until thin set so that I could manually roll everything out.

Now I have experience!

Thanks..alan

[Landlubber]

Yeah it is standard practice to shut off the resin before full saturation, however there is nothing wrong with the resin above the job ( as long as you have it valved of course).

[gamecock413]

I think i got the image in, you can do this, it works well.

[gamecock413]

oh yeah, if you are going to use epoxy you are going to need to ramp up the temp of your part after infusion to gel the resin. otherwise you will get outgassing and undesirable bubbles.the supply pot was good at just below the flange of the mold. a polyethelene rope was used for even vacuum around the mold, incatec is the 3 black strips with three infusion ports, but only one supply pot and one vacuum. I am assuming you know everything else you need.

This is a finished version of that boat. This one was handlayed though. the infused is still in trim out. It sold at the NE Boat show this past weekend.

[JRL]

Originally Posted by ahender

Hi:
Am I wrong in assuming that I can place the resin infusion line at the top of my male mold with the resin flowing downward?

thanks...alan

You can do that. You have to surround the entire part with vacuum. I made some radom couplers using that exact method. Just make sure ever square inch of cloth you want to wet out is covered in some type of flow medium.