Can ISOPROPYL be used to clean the model before painting?

Absolutely. Ronsonol lighter fluid also works really wel

If you light it as well, it really gets it clean and FAST!

I just prime with Tamiya Extra Fine or Mr Surfacer 1200,I have to say that I have not experienced one of those greasy mold release kits folks talk about.The primer seems to cover up any hand oils from handling,and works well with resin or PE,so far no adhesion problems in 20 years of modeling.

Got to agree with Anthony

Even though he's a Raiders fan, I too will agree with Anthony.

Same here! I’ve never an issue with greasy kits. I use cheap, old DupliColor rattle can primer from Walmart.

I guess that's my problem

I got IPA in a small spray bottle that I'll hit a model with before priming. I'll also use windex when there is a lot of dust from sanding filler and resin. The nice thing about IPA tho is it drys fast.

I pre-wash. Always have & always will. So, I don't know if that prevents problems further down the road or not.
I don't prime unless there's resin and/or a LOT of PE.
I did try ONCE doing an IPA (not the beer) wipe down using Q-tips but knocked off a couple of parts. But never had any grief before so why invite trouble and never did it again.
But I always wash my hands before starting construction and don't snack at the bench. So no outside oils in play.
I have a couple of old kits I could try straight out of the bags and see how that works. Because washing ranks just ahead of cleaning road wheel seams and indy track links.

I'd like to say I always wash my hands before sitting down to build but I've walked by my hobby desk right after being outside working on something or other with oil, grease, paint or good old dirt and chunks of vegetation up to the shoulders and I look at something, sit down and think "just a minute to do this and then I'll go clean up". Only to realize a couple hours have gone by, I'm filthy, sweaty and I've gotten finger prints on the plastic. I spritz the model with IPA give it a gentle scrub with a 1/2 wide soft brush, then hit it again with IPA. I'll use a paper towel or q-tip to soak up the excess.

50+ years of modeling and I have never washed/cleaned before painting. Never had any issues with paint adhesion.

When ready to AB, I'll use a soft bristle brush all over, then shoot it with the AB in the spray booth to suck off any remaining dust. My thought is that the dust acts like "dry-sweep" and soaks up release chems/finger oils.

Thanks guys: I think in the future I will just spray with Windex, and rinse. Seems the easiest way.

One more "same here" from me I use Tamiya Extra Fine (L) primer 99% of the time and no problem with any surface or greasy fingerprints...
cheers,
Zsolt

I work a lot with PE and find that using windex weaken the adherence of CA glues quite a bit, so I don’t clean anymore either, nor do I use primers, most primers are to thick. Never had a problem with paint adhesion.
DJ

^^Ditto^^

My models don't get greasy and messy when I build them. Never have seen the need to add another layer of paint to cover up fine details either.

I seldom clean or even "wash" the parts of kits anymore, unless I notice excessive mold release agent on them, or have created a lot of dust in the building process.. This can be a problem with some kits, but with the newer kits coming out, it's becoming less of a requirement. I do occasionally prime, but even that isn't a requirement for me-- only if I suspect I might be doing some heavier weathering or using acrylics for the basic paint. I've found if you use properly thinned/mixed lacquer or enamel paints for the base coat, priming can be an unnecessary step in the process. But occasionally I'll prime with either Alclad microprimer/porefiller, or Gunze Mr. Surfacer. Sometimes I'll use Floquil Old Silver as a primer for metallic finishes. I shy away from rattle can primers, because I like to achieve a more uniform finish. But basically, by using these primers it means I don't need to "clean" unless I've generated a lot of dust in the building process. It just depends on the model.
VR, Russ

The event that convinced me to wash the part before assembly was when I was in Korea I'd picked up the 1/32 Tamiya F-14 at a hobby shop in Osan and I saw Tamiya paint so I figured I'd give them a try so I got the colors I needed and some thinner and the guy at the shop gave me some instruction on their use. I didn't wash the parts because they didn't feel greasy and got to building. If you've ever seen that kit you'd know that is a lot of real estate to paint so I started by shooting flat white in the interior side of forward fuselage halves and grey on the wings which had been completed. Shortly after the paint got touch dry it started to crack and peel. Not from the edges but from the center of the panels. A hard tooth brush removed all he paint in about an hour. Tried again changing the thinner ratio and same thing happened so, irritated, I got back on the bus to Osan and the hobby shop with a piece that had the paint flaking off. The guy looked at it and said he could tell I didn't wash the part before painting. So he sold me a can grey primer, told me wash the parts in cool water with dish soap and to rinse them well and let dry completely then prime and let it dry for 24 hours before attempting to paint again. Well it worked great so the plane looked awesome but I wasn't impressed tamiya paint only used it for brushing after that. That was in 91 and I didn't use tamiya paint again until 09. But I started washing all the sprues after that kit.

I think we all have "horror" story's about paint and "unwashed" parts-- but even washing is no guarantee-- I built the Revell Germany issue of the HMS Bounty a few years back, and it didn't matter how much "washing" I did, I couldn't get any paint, Acrylics or Enamels to adhere to the masts-- it went on fine, but 2-3 hours after, it would split and peel along the length of the mast. I tried sanding, washing with IPA, brake fluid, oven cleaner. I final sprayed the masts with a light coat of pure lacquer thinner, hung them up to dry for a day, and then painted them Gunze Mr. Color lacquer white. the main mast showed a slight crack along the length, which I touched up with white lacquer. The model has been on the display shelf about 12 years now--and the paint is still holding. Another was the Aurora 1/48 Breuget 14, an ancient 1963 kit I gutted and rebuilt, scratching everything except the fuselage and wings-- and those were completely sanded-- yet I couldn't get any paint or primer to adhere to the wings! I finally resorted to a quick lacquer thinner "bath" for the wings, which seemed to work. So there are some kits which will just be difficult, others will be fine. I build a lot of WnW kits now-- I find primer just gets in the way. But I wouldn't build a Roden kit without washing and priming it. East European kits seem to be the worst.
VR, Russ

I had some issues with SKIF kits. You handled the parts and your fingers were left with a wax like film on them.

I read about washing models when I got back into the hobby again, so I ran a little experiment:

I rattle canned a 53 Corvette with Tamiya and used an alcohol wipe I *ahem" 'acquired' from work on a battleship and used the AB on both of them.

I noticed that the paint held on really, really well to both of the models and anyone would have a pretty tricky time telling the difference.

I find that if the paint has a hot thinner to it you will most likely be Ok. Tamiya spray paint has a hot thinner and it binds well. I use acrylics and I like to use Tamiya fine primer first because it binds well to the plastic and provides a good tooth for the acrylics. As far as washing try doing automobiles. One case of fish eye will convince you to pre-wash. I would wash shortly prior to painting. Who knows what you might have unknowingly transferred to the plastic from your hands.

When I was using nothing but enamels and lacquers, I didn't wash sprues. The solvents probably cut right thru any leftover residue. But I wouldn't want to try it with acrylics, I found out how picky they can so why take a chance.