Waxing & Applying PVA ?'s

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#1

Sorry for all the newbie questions. :o I’ve done both of these and haven’t really had any problems with any parts sticking but I’m just looking to improve on my techniques, especially waxing. Funny, it seems like this would be the easiest of all the steps involved. :smiley: What do you use to apply and buff the wax? Whenever I do it, I no longer have that perfect surface I worked so hard to get. I don’t know if it’s because I might not be letting the wax dry enough before buffing or if it’s what I use to apply and buff. The latest thing I’ve tried are these:

They work ok, but again, the surface isn’t perfect anymore. I don’t know if lint is getting in it or what. On the back of the wax it says that “Turkish Toweling” is suggested. What the heck is that? Is it a type of cloth or a technique? :confused:

I’ve read different things about PVA from using a foam brush to a PVA soaked rag to spray bottles to spraying with an HVLP gun. What’s everyone do here? I’ve tried the foam brush and it works ok, but the HVLP gun works better. I figure it’s probably the best, but just figured I’d ask.

Again, thanks to everyone for making this a great forum!

#2

Ive never used pva. I dont like the extra work involved with sanding down your mold surface and buffing out. I make my plugs have a class “A” finish before I mold up and only use wax.

I use TR HIGH TEMP Wax and what I apply with is nothing more than a rag from the box of rags at Lowes. Its T-SHIRT material cut up into 12X8 rectangles. I use the same one and keep it in the can with the wax, its been in there so long I almost dont have to rub the shirt in the wax as its saturated already.

To buff it off I use a fleece cloth, its fuzzy and soft and wicks up the wax fast. I rotate the fleece alot and keep rubbing it off.

Ive not had any problems with this method so far.

#3

I have never used PVA either, and have not had any problems with parts releasing.

On a new mould though it is a very good idea to apply multiple coats of wax, rather than just one or two.

It sounds as though you are trying to buff wax before its properly dryed, or are possibly not using a specific mould release wax.

Chris

#4

“…I no longer have that perfect surface I worked so hard to get.”

Please clarify that statement: is the mold damaged from sticking parts or rough from wedging out parts or the surface has wax build up?

#5

Thanks a lot guys! To clarify, it has wax buildup. It seems like there’s a fine line of when you need to buff the wax. If you let it go longer than a few minutes it’s a royal pain to try and buff usually. Oh, I’m using Partall #2, at least I think that’s it. I’ll double check when I get home. I know it’s at least Partall.

I hadn’t thought of trying fleece, it seemed like that would leave a lot of lint on the surface, but I may try it now. :smiley:

#6

Ive left wax sit overnite and buffed off the next day.

Yeah fleece does do a bit of lint and the wax tends to powder on you when you buff it off but Im a painter as well so I have Tack Rags for painting and if it doesnt clean off with compressed air I tack rag it just before shooting the gelcoat.

Just remember tack rags are not just a one time use. Keep them in a ziplock baggie and keep using them till they stop sticking.

#7

Partall #2 wax is very hard to buff off by hand. The TR wax that Hybridracers recommended goes on smoother and buffs off easier than Partall.

#8

I would agree that Partall is difficult to buff. No, let me rephrase that, a total pain in the you know what. It leaves a sticky type of surface residue. I also found that when you use a power buffer, it just liquefies again and smears around. When you stop buffing and it cools, back to goo. I usually only use one or two coats over a semi perm sealer.

#9

Interesting! You use wax over a semi-perm. We have used both, seperately, but never together. What is the advantage? What is your preferd brand of semi-perm?

#10

Even with semi-pernament mold releases, you should once a year or so still use wax the mold depending how much the mold gets used.

Ourselves, whatever brand that I can get donated… TR right now.

#11

For dry material layup in the mold prior to infusion, I prefer the surface traction that the waxed surface gives. With the full semi perm systems like Zyvax (http://www.zyvax.com/) they are great release systems, but with dry layup I sometimes have difficulty with the material holding tightly against the mold. Its almost like they are too slippery for dry layup. The semi perm base gives me the confidence that I will also get a good release. With just wax alone, I cannot say that I always have a high confidence level that the piece will release easily.