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Using 710 and/or 700 without wiping?

#1
New poster here. I blast and refinish antique and vintage metal patio furniture. Been using U-Tech epoxy then single stage, but recently tried SPI epoxy and like it. Got a few fisheyes and Barry suggested prepping with 700 waterborn w&g remover. My dilemma is the fine texture of my blast profile causes any wiping towels or rags to leave enough fiber "fur" to show up in the paint job. Tried using a red Scotchbrite instead of blue shop towels and fibers still present. Even after blowing off with a leaf blower. So here's my question:
If I hang the parts (after blasting) and douse them with enough 700 to drip off, can I avoid the whole wipe down process and still have good surface prep? I would still hit them with the leaf blower after dripping stopped.
Thanks,
Jeff
 
#2
Jeff, providing your blast cabinet isn't used for greasy engine parts and full of contaminants, I'd try wiping pre-blasting, then media blast, blow off with CLEAN compressed air, and go straight to epoxy, see if you still have the issue.

I think by not wiping the w/g removers will be bringing the impurities to the surface but they would still remain, thus so would your fisheyes.
 
#3
Thanks Robert. I blast outside and use fresh crushed glass every job to minimize contamination. Had a bad outcome trying to save money and recycling the grit - never again and crushed glass is cheap. If I 700 then wipe before blasting that should take care of any top contaminants, but my fear is what's under the layers of paint and rust. I may start hot pressure washing this stuff before I blast.
 
#5
You may just be getting too close with the spray gun in some areas and getting it on too thick, which will cause something similar to fish eyes with SPI epoxy. I'm sure Barry could fix that with a formula change, but we don't want to loose any of the good properties of the epoxy---tit for tat. So you just have to maintain proper spraying techniques, and I'm sure that will be challenging with what you are spraying.

Sometimes I clean only before blasting, and use clean media, and sometimes I clean after and use a SS wire brush to clean off the lint.
 
#8
Anytime I blast metal, the metal has a clean look to it, after a wipe down, the prep wipe will still have grey on it. I clean until no more grey on the rag, then blow with compressed air.
 

Chris_Hamilton

Trying to be the best me, I can be
#9
Like Chevman said there's a strong possibility what you are seeing are not fisheyes. Spraying it too thick (even just barely) will cause craters that look just like fisheyes. Spray your first coat light with a touch more air pressure, then come back with a heavier/wetter 2nd coat and see if that solves your issue.
 
#10
X3 those are likely not fisheyes but craters from laying the first coat on too thick. At least that is my experience...

Skip the wax and grease remover after blasting and spray the first coat of epoxy a little lighter.

Don
 

bing98

New Member
#12
Metal, are you saying that applying the wax and grease remover with the red scotchbrite pad left particles in the sand blasted steel?

I have to clean some hard to reach and complex areas of my undercarriage after blasting. Using towels of any sort would leave a shredded mess between the sand blast profile and all of the edges and holes in the floor pan and rails so I surmised that applying with the red scotchbrite pad would provide the scrubbing/cleaning action to loosen the bad stuff. I would then give the area another quick spray of wax and grease remover and then blot vs wipe it off with a paper towel. I would follow with some compressed air to dry out the seams and overlapping panels.

I thought this was a good plan until I read you post.
 
#14
You can also spray the W&G remover and wipe off with as usual. Then use a tack cloth to remove the "fur" followed by compressed air to insure everything is clean and dry.
 

bing98

New Member
#15
Danny you are referring to the Epoxy, correct?

R/T, here is a pic of the area I'm working in. Lots of nooks and crannies and sharp edges. Combined with the sand blasting roughness any paper type towel would get shredded. That's why I was wondering if the technique I proposed would be effective. I tend to be anal with this kind of stuff because I don't want all my hard work to be wasted.
IMG_4026.JPG
 
#16
most of the time after i blast i will spray the 710 until its dripping off the part on to the floor then i will blow it dry. i never touch the part with a rag after the blasting.
 
#17
Yes the epoxy too thick will look like fish eyes on some areas adjust your gun so spray nice and med wet coat just enough...let it flash and do more coat if you want i always let it induce overnight or 1-2 hrs
 
#18
Danny you are referring to the Epoxy, correct?

R/T, here is a pic of the area I'm working in. Lots of nooks and crannies and sharp edges. Combined with the sand blasting roughness any paper type towel would get shredded. That's why I was wondering if the technique I proposed would be effective. I tend to be anal with this kind of stuff because I don't want all my hard work to be wasted.
View attachment 6141
You need to cut open that frame rail. Guarantee there is a bunch of rust inside there.
 
#19
Not too long ago a friend mentioned he had solved his fish eye problem when he quit using his leaf blower to blow out the booth and shop.....two cycle engine putting oily exhaust into the air.

John
 
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