Hi Mannime,
You don't need to buy all of those release agents; they each have their purpose and sometimes, for certain applications we use them in combination so it depends what you're doing as to which you'll need.
PVA will leave swirls on the surface of parts which are time consuming to buff away so it's rarely used for marking parts themselves. We do sometimes use it when going from a pattern to a mould or, very occasionally, when taking the first part out of a new mould. You can use it on its own or in combination with wax although this more more of a doubling up process since the PVA won't really go down properly over the wax, it will however fill in for any areas you've missed during your wax applications.
[In combination with wax, several applications of wax would go down before a single application of PVA]
Number 8 Wax can be used when going from a pattern to a mould or from a mould to your parts. It will leave a glossy finish on your parts and you might be able to get more than one release without needing to re-apply. Gradually the wax will build up though and it will need stripping off and starting again.
Wax and PVA can be used together (wax first, see notes below) but this is only necessary if you're particuarly concerned about a release. They don't really work too well together (the PVA will bead off the wax) but at the same time the PVA will find any areas you might have consistantly missed with the wax.
Wax and Easy-Lease can be used together but again only if you are particuarly worried about release problems. This would only ever be done when going from a pattern to a mould or on the first release from a new mould. Generally Easy-Lease or wax would be used on their own and woudl be fine.
[In combination with PVA, several applications of wax would go down before a single application of PVA]
[In combination with Easy-Lease, several applications of Easy-Lease can be followed by several coats of wax]
Easy-Lease Chemical Release Agent is the release agent we use more than any other. It's very reliable (providing that the mould and resin are compatible), is semi-permenant (you can get probably 20 releases off a glass sheet for example), it's easy to apply and very 'slippy' meaning that parts will release very easily from moulds.
Easy-Lease is suitable for pattern to mould use (although you may choose to use wax on top of the Easy-Lease) and particularly suitable for releasing parts from moulds where its high gloss and semi permenant character make it very effective.
[In combination with Easy-Lease, several applications of Easy-Lease can be followed by several coats of wax]
The surface on which I'm going to do a vacuum infusion would be one of these:
- Polypropylene sheet- Polycarbonate sheet- PVC sheet
- Plexiglass (perspex) sheet
If you're making flat sheet I would always recommend a glass sheet. Glass is glossier, flatter and much harder to scratch that anything you've mentioned in your list. Normal glass (float) can be used or, for regular use, toughened glass is supurb. From your list, if you were to use polyproplylene sheet then you wouldn't need to use any release agent at all because epoxy resin won't stick at all to it (and nor would it to PTFE for that matter).
I hope this helps.
Matt
Matt StathamEasy Composites / Carbon Mods - Technical Sales