What can I use as mold release? I am tinkering with something new and want to pour some resin into a baking sheet but obviously don’t want it to stick… Actually, is it even a concern? Will poly hotcoat resin even stick to the metal baking sheet?
Thanks in advance…
Santiago
Well, you can buy mold release at stores like TapPlastics… the dark green stuff that dries pretty fast, then ready set go.
Or wax.
Wax paper
Pam
Oil
Anything else?
Resin may stick to metal, not completely, but enough to make mold removal a real difficult task.
Mold release can be simply a layer of wax (paraffin) smoothed on. Wax your mold as you would wax your board, then use a heat gun to liquify it and flow it around the mold.
PAM cooking spray would probably work too. Depends on whether a little residue will affect the next step(s).
I’ve used saran wrap but over three-dimensional surfaces it will be wrinkly unless you can stretch it to conform without wrinkles.
I think a little liquid soap, allowed to dry, would make a water-soluble mold release.
jimmychuck…
You ca use PVA (Polyvinyl Alcohol) Partall Film # 10 from Rexco, or a similar product from Dura Technologies - (DTE 2500). These are water soluble products you can either spray or brush on. If you like you can use Meguiar’s # 16 or # 8 release wax. Both are used in the soft tooling industry.
You can call the Rexco folks in should be able to get a free sample…
Good luck!!
Ken
I’ve used a couple coats of Johnson’s Paste Wax on a mold and it works with epoxy or poly resin as a release agent.
Thanks for all the suggestions guys.
I’ll give it a shot… starting with the simpler suggestions and moving up from there. This isn’t for a critical application so I’ve got some room to play with.
Santiago
Hey Santiago, I have PVA you can use if you don’t have any luck with the other stuff you try…
Thanks Keith.
I’m gonna try to do a test tonight so should know soon.
If you check the ingredients, I believe you can use hair spray,
check the ingredients, mostly propellant and PVA (PolyVinyl Alcohol),
I think the brand may be white rain, but check ingredients,
have used it on small parts for release agent,
just ignore the looks at the check out counter
Best Regards,
Pete
Seems to be the week for me popping outdated posts!
Been looking into release agents, etc and wondering how residue cleanup is going to go. That is, residue on the product removed from the mold.
I understand that PVA release washes out with detergant and water. But I can’t seem to find any locally.
I could use a wax based polish/release. But the I’d have to use a wax remover to get rid of any residue (wouldn’t I?).
I noticed there are some nice spray-on, quick dry Silicon Sprays. These look like they are ideal for use with balsa/EPS (at least, once they are dry). But I have no idea whether residue cleanup is an issue or not.
So, with all that in mind would anyone care to share what mold release they use and how they address the possible issue of residue.
Thanks in advance,
Stay away from the silicone mold releases. Especially the sprays. It goes everywhere, and you don’t realize it. It will get on things you have several yards away that you thought were a safe distance. If it gets on your blank or cloth, it’s going to cause bonding issues. Also, it doesn’t come off. Don’t use it if you need to bond something to your part. If you use a wax, acetone is a pretty good wax remover. If you are just doing something flat, polyethylene sheet works good.
Hey doug. You are right, you will always get some residue left behind. Yes PVA will wash off in water. Wax can removed with some wax and grease remover or a light sand. Best to use proper mould release wax. Rub it on and polish it off. Four to six coats on a new mould. Leaving about 15 minutes between waxes to let the previous coat go hard after polishing off.
FGI has a outlet in Green Fields. http://fgi.findnearest.com.au/findnearest.asp?submittopage=locatorprofile.asp&bid=&locationid=443629&log=1&OriginSuburbPostcode=&returnURL=http://fgi.findnearest.com.au/findnearest.asp%3fsubmittopage=locatorresult.asp#locationmap You will get everything you need from them. Hope this helps.platty.
Kenz,
PE sheet sounds really nice, esp for a “cookie tray”, which I’ll be using. Tnx for the wax removal tip, too.
Platty,
Thanks for that.
I now find myself wondering whether I can use carnumba car polish. Cos a quick search on the net turned up a carnuba mold release that looks like it has the same main ingredients.
4 coats x (15 minutes wait + 5 minutes application) = 80 minutes!
6 coats x (15 minutes wait + 5 minutes application) = 120 minutes!
Is that much really necessary for a flat “cookie tray”???
Thanks again for the thoughts guys.
I use the mequiers #87 mold release. It works great and is easy to use.
I think all/most waxes can be removed with soap. Maybe warm water for harder waxes?
Hey Doug. Some of the older mould release waxes have a canuba base. The reason behind leaving it for 10 /15 minutes between applications is to let the wax harden. If you go over it straight away you will soften the previous layer. So in effect you are only waxing the job once. What are you making in the cookie tray? platty.
DanB, Kai,
Thanks for the thoughts and tips.
Platty,
Is there a particular advantage in a non-canuba wax. Guess I see the need for multiple layers now. And the wait in between. Guess I’ll start with 4 laayers OR try PE sheeting (see if I can find it today). As to the what preformed skin for bottom up balsa sando. See, I have all the materials (and vac setup) now and I’m busy making templates and cookie trays and rocker templates and hotwires and… 
So two (maybe three) answers to mold release wax remover. Soapy water (which would also work for blush removal), acetone and a “commercial wax remover”.
Thanks again all.
The Best thing is what some of the boys have said PETROLUEM JELLY
It’s cheap as chips and always let’s go.
Regards Finfektion
I’ve been using carnuba as mold release for my fin panels. One layer, don’t wait for it to harden or anything. I do have to pry them up but once air starts getting underneath it comes up easily. I can slightly see the pattern of swirls from my hand motion when applying it.
If you put 5 layers on wouldn’t that cause some discrepency from the mold shape where they wax had gone on thinner or thicker?
Anyone know if we could add alcohol to wax and make our own liquid mold release?