crap...need some advice

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#1

I thought this would be a perfect infusion…ohh I was soo wrong…

test piece:
two layers of 9oz twill glass
initial layer of 3mm soric
second layer of soric (center section for rigidity)
two layers of 9oz twill glass

the vacuum and infusion mesh are located directly on top of the glass and soric, in hopes there would be no transfer issues.

Vacuum was good across the entire setup, but it appeared like I couldn’t get resin flow into the soric, it basically stalled out.
what would cause the resin not to flow into the soric channels? if that was the issue.

This is a custom Targa top I’m attempting to create.

https://www.dropbox.com/s/8s4vt5zml7biimq/2014-03-19%2019.23.54.jpg
https://www.dropbox.com/s/m4nm9gbe4tj3i3r/2014-03-19%2019.24.04.jpg

#2

Lots of guys on the forum with TONS more knowledge than I’ve got, but I’m guessing the first questions will revolve around resin viscosity.

#3

…followed shortly thereafter by questions concerning absolute vacuum pressure attained and maintained. Let’s see how far off the mark I am… :slight_smile:

#4

OK, lets start:

-what is your resin viscosity?
-what vacuum pressure did you achieve?

DallasAB, 10 points… :slight_smile:

-how long did you maintain that pressure, before opening the resin valve?
-if I understand right, the infusion mesh is under the spiral, and over the complete laminate, right?

Some observations:
-there is some bridging on the right side.
-the soric is not under the spiral
-resin pot is probably on the same workbench, as I see some resin pooling on the second photo, on the right, at the black tape which holds the spiral

In any case:
-make sure you have the deepest vacuum achievable.
-make sure you maintain that vacuum for at least 30 minutes, to allow the hollow soric spheres to equalise pressure. (very important, and best kept secret)
-if you want the soric to act as a flow medium, make sure the resin can enter it without obstructions.
-make sure there is no bridging, although a generous brake zone, or MTI hose will help avoid problems

#5

is the flow media inside the laminate? It’s hard to see the setup in the picture.

You’re worried about transfer on the back side of the part? I always put peel ply and then the flow media on top (outside), running across most the part with a brake before the vacuum. Haven’t had issues of transfer. I also gave up on spiral media… figured it just wastes a bit of resin and didn’t really seem to help much, generally i’ll just use flow media, doubled up if i’m worried about it.

#6

Viscosity is around 300.
Vacuum was around 29 inHg
mold is flat apart from secondary soric layer in the middle.
vacuum was held around 35 minutes before infusion with no bag leaks.
Correct, infusion mesh was on top of peel ply which was on top of soric, trying to make sure resin flowed into the soric.
Think ill try placing spiral tubing directly onto soric and report back.

#7

First I would use peel ply over the entire piece. I would also cover the infusion side spiral with peel ply. A break zone with peel ply at the vacumn side. I usually use mesh over the part and not all the the way to the vac line. With the soric you shouldn’t need mesh at all. Also the resin feed needs to touch the beginning of the soric. These are just my practices. Hope this helps.

#8

Well gents we had success!! I placed the feed spiral directly on to the soric and the vacuum mesh also directly onto the soric. the first 15oz of resin was sucked up so fast I nearly missed it.
total resin usage was 70oz. the glass is the same weight as the carbon but I’m not 100% sure on how close the resin consumption will be when laying up a carbon version.

#9

Final pics or it didn’t happen :smiley: !

#10

here you go, one before removing the other are testing fitting with some old T-top locking sections.
roof still full of clay and sticky stuff from the mold making :slight_smile:

https://www.dropbox.com/s/3xayhcqmjdpolaq/2014-03-21%2015.13.39.jpg

https://www.dropbox.com/s/9kzwe1ch4cc7dfk/2014-03-22%2020.58.32.jpg

#11

Looks great, glad it worked out for you.