Expanding foam for mould, solid enough ?

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Expanding foam for mould, solid enough ?

Expanding foam for mould, solid enough ?

Author	Message
TURK	TURK posted 10 Years Ago HOT Topic Details
Group: Forum Members Posts: 101, Visits: 662	Hi all, Anybody used the expanding foam you can buy from the diy stores, in aerosol form. I'd like to know what the difference is between that, and the 2 part stuff available. I understand that the 2 part stuff may be 'closed cell', probably making it harder. But can I get away with using the normal aerosol stuff usually used for insulation purposes ? I'd like to spray it into a form ( female mould ) about the size of a shoe box, then demould the expanded spray foam, and then brush on layers of Pattern-Coat Primer to make it harder to use as a main male mould. TURK Tags expanding foam Insulation Foam mould
	Reply Like 9
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	In essence, the HDT rating of a resin is a pretty useless value for most users, as it is the temperature at which the resin deflects under load. This is normally a temperature that is somewhat higher than the actual Tg of the resin (hence why manufacturers like to quote it in their data, as it makes their resin sound like it takes more heat), which means your resin is likely to be softening up before it gets to 80 degrees. If that's the case, I'd be cautious with it if you need to go as high as 120 or even 100. You may find that it will lose its form at those temperatures, ruining all the work you put into getting it dimensionally accurate. That said, I don't have any experience with that resin or with vacuum forming. If they say specifically that it can be used for that purpose then I'm sure it will be fine.
	Reply Like 4
TURK	TURK posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 101, Visits: 662	Hi Hanaldo, I hear you, and totally agree ........ but I haven't got to where I am with my project by 'playing it safe' ! I constantly take chances on my projects, I think we all do when confronted by new procedures, as we're not sure if they'll work or not. I think this is how we learn what works and what doesn't, and from that, we tend to develop our own 'style'. I'm still at the research stage at the moment, hence all the questions. In fact, the mould which will culminate to a working plug, may even turn out to be a female mould. It would most certainly suite my final ABS part, as the shrinkage of the material would ease the release of the part, as a male mould would have the effect of clamping down onto the plug making demoulding that much harder. Many thanks for all the info guy's, armed with my new found knowledge I now have a clearer picture of what to expect. I'll keep you all posted. Alternatively, you can see the entire project on the 'vwt4forum'. TURK
	Reply Like 4