William, The data sheet for Ampreg 20 (the resin supplied by Europa
throughout my build) with standard hardener gives the following for
differing post cure regimes:
Post Cure Flexural strength Tensile Strength. Glass transition
Temp
Regime (MPa)
5hrs @ 80 C. 159 80
78 C.
16hrs @ 50 C. 167 85
71 C.
4wks @ RT 126 71
51 C.
Clearly it's well worth while doing a 50 C. post cure, where the bits need
only simple support, as opposed to 80 C where without complex support there
is a risk of them ending up looking like a Salvador Dali painting! I did
mine by making an enclosure from polystyrene sheets and heated by a hair
dryer, with thermometer stuck thru the polystyrene. Other resin systems I
have worked with, have much less benefit from post cure regimes and if you
are not using Ampreg it would be worth looking at the specific data sheet.
Regards, David Joyce, G-XSDJ
----- Original Message -----
From: "William Daniell" <wdaniell@etb.net.co>
Sent: Tuesday, September 11, 2007 2:25 PM
Subject: Europa-List: Post cure
>
> As I understand it the blue foam bits need post cure.
>
> I believe this is 40C for a period of 24 hours.
>
> Can this be done at a lower heat for longer time to get the same results?
>
> Will
>
> 17:43
>
>
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