High build primer source and alternatives

Gennady

Member
Hello gang.
Looking into reasonable alternative to high build primer (AKA sandable primer, AKA filer primer). Better be epoxy. I checked local stores, automotive suppliers and body shops, Amazon... Price is too high for my budget.
I am going to rebuild/repaint my newly acquired milling machine.

This what I did.
Option one - epoxy resin with solid filler, diluted with acetone to pass trough spray nozzle. Not really chip either, messy, with very limited work time and fear to clog spray gun.
Option two - regular rustoleum primer with 20% solids (either talkum or chalk) also diluted for spraying. Not as strong as epoxy, though cheap and less intimidating.

Are there any other options?
Thanks.
 

Gennady

Member
Well, casting is not that rough to use conventional body filler. It is more like an "orange skin" that is possible to have a good finish with just high build primer. Why I want "good finish" ? good question - I don't have right answer... just because...
 

Upnorth

Well-Known Member
Check out Aircraft Spruce. They should have something that people use when they build composite airplanes.
 

crittermutt

Active Member
That is a primer sealer. Very little fill quality. This is the stuff. It's not an epoxy base. You don't really need epoxy if not out in weather. 2k urethane primer surface is all you need. Put on 3 good coats and after the 3 coat take a cheap black spray bomb and give it a speckled finish. That act's as a guide coat.
 

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phaxtris

(Ryan)
Premium Member
Premium Member
You can buy 2k epoxy primer as a 2 part to spray with a gun, or as a 2 part rattle can (one time use) at just about any body supply store

2 part out of a gun has a reasonable amount of build up, plenty to get rid of orange peel

Pro form will be the easiest to find in canada
 

PeterT

Ultra Member
Premium Member
Option one - epoxy resin with solid filler, diluted with acetone to pass trough spray nozzle.
Acetone with epoxy for viscosity reduction is not recommended even though its 'out there' on the Interweb. Acetone is an effective epoxy solvent, which is why its used for cleanup or inter-coat wipe down. Acetone effectively breaks the long molecular chains which does reduce viscosity, unfortunately it also buggers up the ability for the long chain structure to reform properly if at all. So what that means in real life is problems ranging from inhibited cure time, stickiness (sanding problems), lack of adhesion, strength & other degradations. Thinner addition to resins probably originates from polyester & vinylester resins; there they use styrene in small concentrations & also adjust the catalyst. Epoxy is A+B in exact proportions The End. In paint & primer & sealer systems, generally wise to use the manufacturers recommended thinners unless you really know your chemistry. Many come ready to spray so the appropriate gun viscosity is already there.

There has been quite a bit of painting discussion on the forum, materials, pros & cons if you do a search.
 

wmetfab

Well-Known Member
U might look into a product called Glaze, in a tube.
Its an easily sandable primer putty for small imperfections.
Fill, sand, prime and use a regular urethane industrial enamel.

I was visiting a reputable machinery dealer in vancouver years ago.
As we walked around there was this guy hapilly re-painting a machine grey... with a 1" paint brush and an old soup can... and he was doing not a bad job of it!
 
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