Spray on bondo pros and cons

I find Rage gold doesn't much like sticking on bare metal. Goes kinda flakey round the edges and won't feather out properly. With the Standox red/brown i use ...no problem. Same with DP90 and other epoxy urethane primers we use over here.
Other fillers will stick to the metal and sand real good ..but they're the ones that stay real gummy on the top and clog up that 40grit paper! that to me is a waste of time and sandpaper.
as for moisture gettin under the filler ...it only takes a rock chip to start that off,or a small crack on a bodyline where flex occurs(as Jeff Walker observed spray filler seems more brittle than regular fillers or primers)

Here in New Zealand the sun is VERY harsh.Something to do with a big hole in Ozone or something. You can get quite badly sunburnt in 5mins on a relatively overcast day. The UV levels seem to break the paint and its substrates down in fairly short order if the paint isn't protected much (ie garaged car, good waxes etc).Gettin sidetracked now.
I'd have to agree with Scottb that the lines can certainly be kept sharp with spray filler (spritz?) but its NO substitute for proper metalwork.
my .02

 

quick question here: i'm about to attempt my first paint job, the bare metal is in pretty good shape. After i shoot the epoxy primer and sand the filler work, i'm wondering if i should use a hi-build primer or a spray filler like SlickSand?
I can only work on it on the weekends so it'll take a month or two to sand.

 

I don't use Poly as it sucks up moisture like a sponge, not good on glass bodys and even worse on steel.

 

There used to be a product called Amack (I think that is how it was spelled). This stuff was supposedly a Polyester Primer, but you mixed a fiberglass resin type catalyst with it to activate. It went off very quickly, especially on hot days. In fact I lost a very good Binks gun and Sharpe #7 when I got a phone call just after squirting the cab of a 53 F100 with it. 15 minutes later the stuff was hard as a rock and even the paint store guy who cleaned and repaired guns just laughed at it.
Put this stuff really was like spray-able Bondo and it lasted a long time. It also self leveled very nicely and you could actually layer it to fill small to medium sized dents just like regular Bondo if you wanted.
Unfortunately I haven't seen it in years (probably since the early 80's)

 

I am certainly not an expert by any means but my understanding is that you use that stuff in place of a high build primer for finish work.

 

every one will say something diffrent on how to use a product. whatever primer you use ask your local paint shop for a DATA SHEET on that product or look on there web sight for it. it will tell you step by step how to use the product or simply read the lable on the can! its there for a reasion.

 

Amack was great. When they quit making it we switched to a SEM product. Almost as good, but it is also no longer made. Both of those products were strong, adhered very well(over bare metal), gave an excellent surface, but were relatively hard to sand. Feather fill is ok, and is much easier to sand, but not as good as the no longer available products mentioned. I am not familiar with any of the other products mentioned.

These spray polyester fillers are intended for final surfacing, not the filling ordinary "Bondo" would be used for. Spray polyester is a standard step on most show cars. For minuimal shrinkage issues and best durability, only a very thin film is ok. Two or three thin coats is better than one or two thicker ones.

 

high build, easy to sand. the bad, brittle and prone to cracks and chipping

 

Amack was bought out and is now PCL polyester.,label/

 

Spies Hecker Raderal Spray Polyester.
Best there is by far.
Spies is the best paint out there. I sprayed Dupont, PPG, BASF, House of Kolor etc etc...

 

I don't know if it's still out there, but I've used a two part product called "Sand-eze" with good results.

 

Do you need to spray on a primer sealer over feathercoat?

 

Yes.