SPI epoxy primer over po 15

R

rusty musket

im getting close to painting my frame and under carriage components of my fj40, if you know what that is then cool. i am sandblastying the fraME however there are sections of the frame that blaster wont reach, i want to paint thos sections with po15. my question is will SPI epoxy primer/sealer go on over the po15? will i have to worry about rust happening? Or>>>> help please
 
the sections of the frame that i want to paint with po15 are the parts that are not very accessible to anything except road grime and water/mud. but i still want to topcoat the po15
 
SPI has nothing that will stick to the por, start with it and finish with it would be my best suggestion.
 
Thanks for all the feed back i read the second link in the reply from chris hamilton. something in that thread cought my eye about metal expanding and contracting and that makes a bit of sense to me. i do have a qt of the stuff and planned on using it but i dont think i will now. i really do want to start and finish with one product and SPI seems to be it. i have a qt of the SPI epoxy primer but i think i will need another gallon/ 2 gl sprayable to finish my project (body and frame). so from what i have learned from this site and a few others is that ospho is prolly gunna be my go to paint to paint over the rust spots of the inner frame. this is a 99.9999% off frame resto in a 2 car garage lol. it really hurts me that i have come this far and cant get every spot of rust off my frame. oh and if it is worth anything i will be applying ppg omni acrylic enamel SS as the top coat. thanks for the help Chris, Barry, Coronet and Shine.
cheers!
 
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also, being in the Navy we work and paint our ships all the all the time. for stubborn rust and sections that would frequently rust we would go get a rust preventitive/inhibitor from our paint/hazmat center they would give us some paint that was white in color but turned black when applied to rust. i cant remember what it was called but from other descriptions it sounds kinda like ospho
 
Just be careful what you use, there are a lot of scams out there.
Bodyshops use sand or Ospho for good reason.
 
Be sure to neutralize the Ospho before applying anything over it. If not it leaves a film that will cause adhesion problems.
I made this mistake once and it cost me a complete redo of the roof on my signature car.
Once you have the rust converted, apply another coat of Ospho and then before it tries wash it off with soap and water using a Maroon Scotchbrite pad. Rinse well and blow dry with an air hose. Wipe it down with 710 Wax and Grease remover and let flash completely.
 
Thank you for the knowledge. I have a quart of primer + the activator, I’ll do the springs and drums first. Still need to order a gallon + activator for frame and panels. I have the WG remover. Slow is fast fast is slooooow
Thanks aGain
 
Haha, there was quite a POR15 debate on a FB thread today where one guy got banned for getting testy defending POR15.... I just said use SPI epoxy and be done with it.
 
Haha, there was quite a POR15 debate on a FB thread today where one guy got banned for getting testy defending POR15.... I just said use SPI epoxy and be done with it.


Agreed.

POR15 is very brittle and doesn't have adequate adhesion to anything but clean, media blasted metal. There is nothing magic about it that makes it more suitable for areas where proper surface prep is not possible. I have tested SPI epoxy on such areas - it holds up a LOT better than POR 15. Cavity wax may be a better option for areas that are truly not accessible. Of course you will want to finish all of your paint work first.
 
i know this is a professional based forum but this last comment made by my wife is to good to let pass: while sitting here reading the replies to my last post, wife just said and i quote "man i really need some cavity wax".
i wont be unprofessional ever again unless she says some funny stuff i know yall would like lol
 
i have some pics here of my project. The frame rails are giving me problems, the best way to get the rust out would be to cut the rivets and pull it apart but im not going that in-depth. Only thing i can think of is a chimney brush and a liberal helping of Ospho. Open to suggestions and scrootney.
DSCN0468.JPG
DSCN0465.JPG
DSCN0466.JPG

blasted axle housing then washed with straight up water no dawn. wiped one section in w&g remover let other section dry under heater. is the orange flash rust from minerals in water and does that have to be worried about?
DSCN0469.JPG


the following is an example for reference of the truck i am restoring and the color i will be painting it. i am a longs ways from painting the body but i would like to have it on hand and know what color epoxy would be best for the basecoat/topcoat (spring green). Gray?
fj40 sg.JPG
 
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SPI Epoxy and some form of cavity wax for areas truly not accessible. Not a big fan of Transtar but they make a decent rustproof kit with extra long tubes to snake into unaccesible areas. #4423 for the rustproof (cavity wax) #4471 for the tubes and nozzles.

Looking at your pics, can you snake the blast nozzle into those holes a bit? Seems open enough to get in there and get some of the rust.
 
that is flash rust on the axle. no need to worry about that. you can epoxy right over it. just do it soon. dont wait a month from now.
 
The weather is warming up out here in Vegas. I thought I should get ready to shoot some epoxy so I rigged up one of those copper air coolers/water separator. Attached to that is an air filter/dryer then I will hook up 50’ of air hose and an in-line desiccant snake. Hers a pic what do you think? Cost $400-$450.43C07B4A-CBA4-4F88-A621-8A0C031112CB.jpeg
 
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