Expanding foam for mould, solid enough ?

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Expanding foam for mould, solid enough ?

Expanding foam for mould, solid enough ?

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TURK	TURK posted 11 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
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Fasta	Fasta posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	It's always a good idea to lay a fibreglass skin over a foam pattern/plug just so you can then sand fair a thick primer or filler until it touches the firm skin here and there. Then add further primers etc. If you just have the soft foam underneath then it becomes difficult to sand any paint or filler as if you sand to touch the foam then it digs a hole in it! Fastacraft Facebook page
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TURK	TURK posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 101, Visits: 662	It's always a good idea to lay a fibreglass skin over a foam pattern/plug just so you can then sand fair a thick primer or filler until it touches the firm skin here and there. Then add further primers etc. If you just have the soft foam underneath then it becomes difficult to sand any paint or filler as if you sand to touch the foam then it digs a hole in it! Won't a few brushed on coats of Pattern-Coat Primer harden the PU foam ? That's a good tip there Fasta my intention was to build it up with body filler, then Pattern-Coat Primer. The polyurethane I'll be pouring into the makeshift moulds, is to get the original contours of the OEM headlight. I had to do it that way as I don't have a CNC machine, to get both headlights identacle shapes in reverse was impossible ........ I know, I tried ! As the OEM headlights are a really poor fit, I want my custom headlight covers to be a tighter fit, so they blend in better with the van panels. So in some places ( top and right hand edges ) I'll be using 5mm EasyCell75 to help the build-up. Then I intend using the procedure above, body filler for final form, then many coats of Patter-Coat Primer. Does anybody foresee any issues glueing two different foams together using a hot glue gun ? Here's the OEM headlight, with added DAS modelling clay to give me a vacuum formable shape >> I'll be using PETG for vacuum forming those, Then I'll add the apertures for the quad headlights, then pour PU foam in them ...... that's the general idea anyway. TURK Edited 11 Years Ago by TURK
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