Would it be best to infuse this part from the middle up toward the sides, from one side to the other or from end to end? This will be my first infusin once I get a better vacuum pump. The whites is epoxy putty I used to fill in the gap when I added the large flanges. Thanks
Probably from the centre outwards.
Please do a vacuum integrity check, before laying up.
Thank you, Herman. Will do.
How do you decide? Is there a formula? A rule?
Trial and error is the only true way to know. There are a few good ideas to help you get started in your planing and then based on each infusion prefect then process.
Try to infuse so that the inlet length/area is larger than the vacuum length/area. This way the resin is not spreading out which could leave areas light on resin. It also helps speed up the last part of the infusion.
Try to have the resin flow uphill in your parts. The resin front will push any trapped air ahead of it and out the part. Going down hill the front can over take the air leaving it in your part.
Try to have your vacuum line near the area that is most likely to leak, that way if there is a leak it will go straight out the bag and not the part. Most often this is the tacky tape or mould joins.
Often these contradict each other so you need to pick which ones are more important. Eg: if your have a good bag then the last one is less important.
That is a very clear explanation Moke, and makes sense. Thank you.
Your bag has to be 100% tight, not 99%!
Out of the four infusions I’ve done I’ve yet to be able to achieve this. Always have a small leak some where that I can’t locate. I guess this is why I end up with small pin holes in the product.
Good explanation by Moke.
One addition: the only way of knowing for sure is a bunch of experience, and a computer simulation: www.polyworx.com. I have worked with them a dozen times, and they are both smart, and developed a proper algorytm.
To get a bag tight most depends on the choice of materials. A good sealant Tape and a multilayer bagging film helps a lot.
For resin flow thats all about experience. I never used polyworx and I never had a problem.
For banneds part: Start with infusion in the middle and vacuum around the perimeter. Make sure you degased your infusion resin, that your vacuum is <20mbar abs. and the bag is tight. As far as I know you ordered some MTI hose so place this direct to your laminate and let the flow media end about 1/2 inch before the MTI hose. Seal the ends of the MTI hose to make sure no redin can get into it or to your pump.
How many feet can be infused? Like what’s the maximum distance that resin can be pulled? Vertically?
The max distance depends on a couple of factors:
-resin viscosity
-laminate permeability
-geltime
-feed capacity
In general a 2 meter distance is the max limit, for a single feed line (perpendicular to feed line)
In height the weight of the resin comes into play, theoretically you can pull up to some 9 meters, but in practice 7 meters is the limit. We once did 13 meters high in a 2 step mechanism.