Resin line locations on large infusion

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#1

Hi,

I have been testing infusion on some small parts and getting fairly good results. I now need to try and infuse some fibreglass onto a large sheet of plywood approximately 2000mm x 1000mm in size.

I would like to try and obtain the quickest infusion time possible and wondering if anyone has any advice on the location of the infusion lines and vacuum line please?

The ply is vacuumed against the glass to give a flat smooth finish, I leave the soric exposed at the edges to allow me to place the vacuum and infusion line in the bag. This also allows me to see the flow through the soric as a visual indication of the location the resin has travelled, very important as the ply sheet makes stops me from seeing the flow, the excess if then trimmed later.

I am unsure if I place the resin feeds on too many sides that some resin will reach the catch pot prematurely? Is this called race tracking? I was thinking of trying the place a resin line fully across side A, half way down to D (creating a 90 degree feed 1000mm x 1000mm) then putting the vacuum in the corner of side B & C (bottom right corner). Im still not sure this is the best method however?

Just wondering if anyone has any experience with this please or any advice?

Thanks very much :o Here’s my diagram:

#2

race tracking is when the resin moves around the part, on the edge of a laminate/core or through a pleat and it bypasses all your laminate and reaches the vacuum line prematurely cutting off vac.

why not have the vac/intake across sides D and B? That would be the shortest path. I think so long as you don’t racetrack, and have the proper peel ply break, things should flow but 40 inches is pretty far.

Another option is to go from the center out to the edges, if it’s ok to feed through the plywood?

How did your test panels do? Did the plywood pressing down on the laminate cause any flow issues?

Also you want a quick infusion time? because of gel time?

#3

Fastest by far is perimeter inwards. So feed on all 4 sides, and vent trough a tiny hole in the middle of the sheet.
Feed resin at the centre of A and C.

This also saves you from fighting racetracking.

If you do not want to drill a hole in the sheet, then from D to B is fastest, but probably 4 times as slow as the earlier option.

#4

Hi,

I can’t drill a hole in the sheet and restricted to using the perimeter only. I can add an inhibitor to slow down gel time but ideally want to obtain the quickest route. The Soric is an excellent flow media however the chop strand is more restrictive than cloth in the tests performed so far.

The longest side (b or d) seems the ideal choice of course for the infusion line but I wanted to try to use b or d with a or c too, this could however cause the resin to reach the pot too soon.

Looks like more testing! Oh my days…

#5

I would place my feed line the entire length of D on top of the exposed soric. I would then place my vac line the entire length of B on top of peel ply 2" or so past the laminate, soric or what ever. I would also use MTI vac hose to ensure an even infusion.

#6

1m is a quiet long distance, depending on flow media, gel time etc. I would place my vac lines (MTI hose) at both sides or around the perimeter and a infusion line in the middle. Thats faster and makes sure that everything will be saturated.

#7

Hi,

I have seen the MTI hose and interested in possibly trying this. Unfortunately we cannot get access through the core so restricted to placing the vacuum lines and resin feeds on the Soric flow media on the outside of the core.

Can you advise the estimated flow efficiency over conventional setups using the MTI in applications such as this please? It seems like a good addition and worth considering.

#8

Looks like we are going to use a foam perforated core to infuse from the centre now which will make things easier as we can use perforated foam and try to infuse from the centre which seems more common. Not sure if the MTI hose is worth the extra money in this application so will maybe wait to try it on something else? Thanks for the replies guys.