All my and my former classroom molds got semi permament mold released!
http://www.chemlease.com/comp_selector_guide.pdf
I use 4190/sealer 15 on alum and frp molds and primed/painted plugs… this stuff is AMAZING. Can easily get 5-10 pulls on simple parts. First part after fresh coat of 4190 about falls out. It’s almost impossible to pull peel ply off parts w/o the part releasing. Another nice thing is you get the mold finish on the part(good or bad), no pva orange peel or wax swirls.
It does require a little more attention for gelcoating, use a couple light mist coats b4 laying down coverage.
When parts start releasing as hard as from a waxed tool, wipe on a quick coat, takes about as long as washing a clean window. Have used it with PER, VER & Epoxy all with great results. Have used it up to 250f cure prepregs w/o problems as well.
It seems expensive… but a gallon will go a LONG way, years in most small shops. 99% of it goes in the trash with the rag used to put it on. I use appilcation rags till they get soiled b4 tossing them.
The only thing I’ve ever had stick with this stuff is fresh green unprimed body fillers on plugs that should have been primed/painted anyway, but ya know what happens when ya get in a hurry!!
There are other similar systems out there, but I can’t say enough good things about chemlease. I tried many systems on my way to discovering this stuff and havn’t been inclined to look for another since.
I use frekote seelaler and 700nc release agent. The sealer is very expensive, $400 a gallon, but works great for purosity, and the release is $70 a gallon, also use freekote cleaner whice is $20 a gallon. It is very important you start off with a very clean surface. you also dont want to apply thick coats, only want to haze this stuff on. but works great, and last a long time
Wow! Thats some expensive stuff!
The semi perm I used at my last job was $60 for the sealer, $60 for the release, and $20 for the cleaner/rinse.
At the end of the day its all water based PTFE, dont care who makes it.
it is expensive, high temp. it was actually a freebie from where I worked before. I got a gallon of sealer, and 6 gallons of release, not to mention many other chemicals and supplies and other goodies
Hey there guys, im just using normal mold release wax but sometimes on complex shaped molds my part still need some extra help to get them out.
Sometimes with this I use wedges and hot water as recommended by the shop who sold me the wax and it makes the part come out pretty easily.
Question though is if I use hot water, would this melt or wash all the wax off the mold?
Thx
When using only wax, the mold will need to be wax every time you use that mold. With Semi Perm. maybe wax once a year or every 6 months.
I use only wax on the moulds for motorcycle tanks I make, and have found I only have to apply one further coat of wax after making several tanks.
Seems to me the main problem many people seme to have with wax is they think that the purpose of waxing is to produce a shiny surface, so buff the wax like they would a car body, which results in a good shine, but little or no wax left on the surface of the mould to allow proper release of parts…
Sorry what I mean was I know that on a fresh mold you put about 5-6 layers of wax on and then after that one or two coats on for every new part you pull off right? Well my question is that since I use hot water to depart some of my parts, would that melt or wash away all the wax? Would I need to put on a new 5-6 layers on again or just one or two?
Thx
Yep. 1 coat of wax before each layup.
And no hot water will not wash the wax away.
If you keep waxing a well aged mould for no good reason, then you will end up with lack of definition on any fine detailed areas, and possibly other associated problems This is something that is quite well covered in the Forbes Aird book (ISBN 1-55788-239-8), which also covers the proper procedure regarding preparing new moulds for first use.
After the last coat of wax is applied to a new mold, how many hours should i wait to spray pva on it and then use it? I’m hoping it’s ok to just wait 2-3 hrs after the final coat of wax is buffed?
why use pva? if you made a gelcoated mold and waxed it, there should be no need to use pva
I don’t want to chance the mold getting any epoxy resin glued to it; PVA is just extra insurance.
I think your waisting your time. just do a tape test to ensure you did a good job, or switch to a semi permenant release. I have only used pva twice in my life, I would only use pva when I have a really old mold that does not have a shiny surface or has alot of purosity. using pva on new gelcoated mold is not neccesary
At my old job we would apply wax and spray almost immediately after buffing. Never had a adverse reaction with PVA.
Im with Hojo though. PVA is a time killer. Some of your higher end parts manufacturers use teflon tape on tool surfaces. For masking and as a release agent (instead of wax).
Didn’t have to wait for the wax to out gas?
I use either wax or semi-permanent release on all molds, never use pva unless the mold is in hagard condition. if you have a mold that is in good condition and you are having problems releasing your parts due to poor waxing job/poor wax, then you really need to switch brands/technique or use a semi.
There is no need at all to wax a mould every time, and you only need to apply 3 coats initially to ensure the whole mould surface is covered.
Detailed info regarding all this can be found in the excellent Forbes Aird composites book.
I’ve never heard of this teflon tape stuff, what is it like?