CNC Machined Polyurethane Foam Sealing

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CNC Machined Polyurethane Foam Sealing

Author	Message
Chris Rogers	C Chris Rogers posted 5 Years Ago HOT Post Details
C Group: Forum Members Posts: 120, Visits: 933	+x allankn - 2/5/2020 8:57:13 PM Chris, just checked out your site and your videos. What a gem!Watch the whole series building the Hyperloop shell. Great!Definitely a subscriber.-Allan Thanks Allan! Great to hear that it is helpful. It's only the beginning, but I'm having lots of fun doing it!
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Aluminium must be much cheaper in the UK/US. I got a quote to have a 300x125 mould machined here, and local suppliers wanted AU$500 just for the billet and another $700 to machine it. I bought a 1500x500x50 block of PU tooling board for $275 and machined it myself...
	Reply Like 3
allankn	a allankn posted 5 Years Ago HOT Post Details
a Group: Forum Members Posts: 8, Visits: 192	Chris, just checked out your site and your videos. What a gem! Watch the whole series building the Hyperloop shell. Great! Definitely a subscriber. -Allan
	Reply Like 3
JLiang	J JLiang posted 5 Years Ago HOT Post Details
J Group: Forum Members Posts: 6, Visits: 57	Perfect. Thanks everyone for all your replies, much appreciated!
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scottracing	scottracing posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 460, Visits: 5.2K	+x JLiang - 1/19/2020 9:58:41 PM +x scottracing - 1/19/2020 9:42:01 PM you will be surprised at the cost of ali tooling against epoxy tooling board,a lot of the tools I make are now made out of aluminiumbescuase of the overall cost is much cheaper. A good machined and polished ali tool will give very good results with chemical release agents. I looked into a few metal moulds, the trouble with my particular part is it's fairly deep, so the stock needs to be quite thick. It does seem easier to work with though! What sort of surface treatment do you do? Just wax and PVA? Sounds like it would save a ton of time. As chris says above,i would use a chemical release agent system. Marbocote is my preffered choice but Chemtrend and Frekote will work too.
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Chris Rogers	C Chris Rogers posted 5 Years Ago HOT Post Details
C Group: Forum Members Posts: 120, Visits: 933	I'll second (third?) the aluminum - it's awesome to deal with and at that size it will be a wash money wise. You'll want to sand it to at least 320 grit - more if you need things shiny. Once the machining marks are gone, Scotchbrite works pretty well. Can you split the mold so that deep feature is easier to machine? I'd recommend a mold release system other than wax though - if you can get it Frekote, Chemlease, or other semi-permanent system. Wax will work though if you buff it out and do a few coats. You shouldn't need the PVA - but it will certainly make demolding easier if there's any doubt. Good luck with the kevlar! If you've been doing MDF in the past, any tooling board will be like a dream - but it is so expensive! Gelcoat to seal the MDF is a real hassle though. I wrote up a post about how to get the best out of MDF - if you find yourself doing bigger parts it may be helpful: https://explorecomposites.com/articles/tooling/using-mdf-for-composites-tooling/
	Reply Like 6
JLiang	J JLiang posted 5 Years Ago HOT Post Details
J Group: Forum Members Posts: 6, Visits: 57	+x KLComposites - 1/20/2020 2:03:39 AM Agreed. Been buying a lot of aluminum from Xometry here in the US, and the price is amazing, even compared to PU board, let alone epoxy. Sweet. I'll look into it more. What sort of surface prep do AL moulds need? Just wax and PVA? Thanks for all the help guys. Edited 5 Years Ago by JLiang
	Reply Like 4
KLComposites	KLComposites posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 26, Visits: 3.2K	Agreed. Been buying a lot of aluminum from Xometry here in the US, and the price is amazing, even compared to PU board, let alone epoxy.
	Reply Like 3
JLiang	J JLiang posted 5 Years Ago HOT Post Details
J Group: Forum Members Posts: 6, Visits: 57	+x scottracing - 1/19/2020 9:42:01 PM you will be surprised at the cost of ali tooling against epoxy tooling board,a lot of the tools I make are now made out of aluminiumbescuase of the overall cost is much cheaper. A good machined and polished ali tool will give very good results with chemical release agents. I looked into a few metal moulds, the trouble with my particular part is it's fairly deep, so the stock needs to be quite thick. It does seem easier to work with though! What sort of surface treatment do you do? Just wax and PVA? Sounds like it would save a ton of time.
	Reply Like 3
scottracing	scottracing posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 460, Visits: 5.2K	you will be surprised at the cost of ali tooling against epoxy tooling board,a lot of the tools I make are now made out of aluminiumbescuase of the overall cost is much cheaper. A good machined and polished ali tool will give very good results with chemical release agents.
	Reply Like 4