Core Material and Infusion

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#1

I have been experimenting with infusion and have had good luck in producing very strong parts. My next project involes a mould that needs some small core material for strength (large flat spans). When I layed the part up wet I used .125" Nomex honeycomb in 2" wide by 12" long strips spacing them 3" apart, overlayed another 3-4 layers of reinforcement (usually s-glass and carbon) placed in under vacuum and cured. Has anyone used core materials in ther infusion projects (Nomex, bulkers, foam) that can direct me? My main concern is with resin voids. I use a Dow Epoxy resin with a ~500cps.

Thanks.
Jeff

BTW, here is a pic of my first infused part. A radiator Cowl for an Acura NSX

#2

lol I found myself loking for the engine and became very confused, then I ralized you wrote nsx not rsx :smiley:

sorry I don’t have any advice:(

#3

I’ve just initiated a similar search myself… Haven’t tried anything yet, but here’s what I have found so far:

Diab Divinycell
Lantor Soric

I know fiberglast.com carries them both, but fiberglast is hella spendy. Let me know if you find a better source.

Cheers,

Ubermotos

#4

We mainly use grid scored and perforated 1/2" Diab urethane foam core. Densities vary depending on application (component size, curvature, strength requirement, etc.)
We’ve also started to use Nidacore 3d foam. Cool stuff, just need to figure out how to get the most from it.

#5

you dont want to infuse honeycomb core since all the cells will fill with resin and defeat your weight to stregth ratio. use a scored closed cell foam , or non-scored can work too in certain situations

#6

perhaps this stuff

http://www.fiberlay.com/

in the infusions link,

on page 3 and 4

I’m not sure what core mat is but it might be what you are looking for?

#7

I don’t know anything about core materials or how to process them, but man… that nsx radiator cover looks really nice:cool:

Gotta love any car that comes standard with titanium connecting rods, even if it’s a Honda!

#8

i use non-scored foam board in the parts that i use to make them extra rigid…its like night and day what a toothpick size piece of foam in the right direction can make on a part…

#9

Thanks for all the info. I was looking at the divinymat myself. I’ll keep everyone posted as to what I choose and the results.

#10

I think I’m gonna try the lantor soric first since it is cheaper and appears to conform to complex shapes better. Sounds like your parts are more flat than mine. Let’s compare results when our parts are done! =)

#11

What lay-up process do you use? For hand laminating, and bagging it’s ok to use regular foam sheets. For infusion, there needs to be a way to distribute the resin to both sides.

#12

i only do hand layups right now…its the most cost effective way to produce parts on a small scale in my opinion…maybe once im cranking out 10+ parts a day on a regular basis ill switch to VIP

i made a carbon fiber brake pedal for my 07 yamaha r1 lastweek…only 4 layers of carbon fiber twill and its SUPER strong…stronger than the alum. stock part, foam core and 2x2 twill with west systems epoxy and electrical tape…

#13

I have infused regular divinycell without scores in it with out a problem, you just have to start your resin flow before the core starts so it can flow under and over the core. the pieces I have done were not huge, but about 10"x20". infused it very well

#14

I think that the infusion worked in that case because the part is so small. Resin will flow through fabric a little bit, even with no flow media. Watch out if you start doing larger stuff the same way!
I’m making stuff that might be 6’x8’, pretty big. No chance of the resing flowing through the bottom side without scored and/or perforated foam or flow media in the bottom plies.

#15

Lots of good ideas… all of which I think I need to test. I’m thinking of trying the Divinymat(perforated and scored) first. It sounds like a tailor made product for what I need.

#16

I’m reviving this thread as I have a few issues with infusing with soric.

The parts I’m making are all sized approx. 1m^2.

Due to mounting points and for trimming purposes, I can’t run the soric right to the edge of the layup, I usually finish about 50mm from the edge. Around the edges I lay a strip of 30mm wide infusion mesh, but always leave a gap between that and the MTI vacuum hose I’m using.
I’ve infused across layups and from the centre outwards and results always seem to be the similar. A very slow infusion (approx 2 hours for a 1m^2 sized part) and when I release the part from the mould, I have air bubbles on the surface where the soric is laid. Also the edges near the MTI hose are often on the dry side.

I am pulling a full vacuum, with no leaks. Drop tests show this.
I degas my resin in an ultrasonic bath for 10/15 minutes before infusing.
I compress/ fully decompress the layup 4/5 times before infusing.
I also make sure the pump is run for at least 20 minutes to fully evacuate the soric.

I’m unsure when to clamp off the resin feed, as the slow infusion really doesn’t make me feel confident to clamp off at say 75% completion, as I’m sure that the edges will be even more dry than usual.

Please help!

#17

do You lay infusion mesh over the are where you have soric or no?! I understend You dont and thats why Your infusion takes that long… what is Your resin viscosity?

#18

I think you might want to ask this in the Mti thread. I would think you would clamp at 100% saturation as the vacuum stops when resin reaches the hose.

#19

I don’t place infusion mesh over the areas with soric as it should not be necessary because the soric is an internal flow media…
I’ll wait to see what response I get here before asking in the MTI thread.

#20

Be careful using soric as you’ll get print through from the core in lighter laminates.
Foam core can be easily thermoformed with a heat gun.