perfect!
--- On Tue, 1/3/12, Philip Lardner <This email address is being protected from spambots. You need JavaScript enabled to view it.> wrote:
From: Philip Lardner <This email address is being protected from spambots. You need JavaScript enabled to view it.>
Subject: RE: [Carbondragonbuildersandpilots] Re: Epoxy resins - strength and suitability
To: This email address is being protected from spambots. You need JavaScript enabled to view it.
Date: Tuesday, January 3, 2012, 6:14 AM
Sealing the edges of foam core sandwiches...
For the larger parts (ribs, etc.) that will be made up individually, the foam core should be fully encapsulated in CF cloth... I just have to be careful to ensure that the vacuum bag and cloth conform to all the edges and corners perfectly before introducing the resin... something I failed to do in my first test part. The vacuum infusion process allows you as much time as you need to get the part absolutely perfect before wetting it with resin - you can apply and remove vacuum, and readjust things as much as you like before comitting to the resin!
For smaller parts that I intend to cut out of a larger sheet of carbon/foam sandwich, I will trim back the foam by a couple of milimeters all round after cutting out the part and back-fill it with Aeropoxy-lite filler compound - then sand the edges to finish. I haven't tested this yet but I don't forsee any problems.
Phil.
From: This email address is being protected from spambots. You need JavaScript enabled to view it. [This email address is being protected from spambots. You need JavaScript enabled to view it.] On Behalf Of Kenny
Sent: 03 January 2012 06:04
To: This email address is being protected from spambots. You need JavaScript enabled to view it.
Subject: [Carbondragonbuildersandpilots] Re: Epoxy resins - strength and suitability
oops, my bad I didn't really look at the numbers The epoxy itself is not that strong (that's as strong as aluminium!). Again, the strength doesn't come from the epoxy anyway, but the fibers (be they glass or carbon).
As far as other choices... I'd use epoxy. There is a reason we don't use milk-glue, or lead paint for that matter... Epoxy is predictable (strength) and when a little care is used (gloves, long sleeves, well-ventilated area), should pose no serious threat.
Have you thought about how you are going to seal the edges? /if you wrap it you might ad significant weight.
