Hello All,
I have heard about Mr. Surfacer and I recently saw a small glass bottle of it and bought one. My questions...can I shoot this through my airbrush and if so how shouldI thin it? Otherwise, can I just brush it on?

Thanks,
Sean

Yes it can be used in your airbrush .... but.
I wouldn´t risk it in mines. If you have an old second brush maybe, but be sure you have the right cleaning stuff, thinner and spray in a well ventilated place.
There are 3 types of Mr. S that I know of. 500, 1000 and 1200(?). The 500 would not be suitable for airbrushing as the grains are larger. This is most useful by brushing on .... it self levels quite well ... and can be sanded. I believe there may be an aerosol version, but I have a good cheap primer from an auto accessory store I use and dont see the point in looking for an item that is probably more expensive.
The thinner stuff(1000 and larger) is useful for brushing on around joints to check for gaps or to tidy up after heavy sanding. Excess can be cleaned away by sanding and/or acetone-free nail polish remover. I use this for cleaning my brushes as well, after useing Mr. Surfacer.
Its a great "tool" to add to your tool box. I use both 500 and 1000 quite a lot and wouldn´t be without either now.

Thanks for the reply Frank. I have the 500 kind and I am not risking it through my airbrush.

The grains are no 'bigger' in 500 but there are more of them per ml of carrier fluid - hence its thicker. Gunze do make a spray can of surfacer and this is indeed very good - it will attach to metal, plastic and resin and then 'shrink' as its drying giving a good strong base coat.

However, I myself use Halfords (auto supplies) grey car primer - it does the same thing for a fraction of the cost.

Lee

Mr Surfacer thins fine with good old fashion Lacquer Thinner. Thin it for airbrush use, it sprays no different than any other primer you thin for spraying. Cleans up with lacquer thinner.
In it's thicker form, (you'll still need to thin it a little) use a larger nozzle, needle, and higher pressure, mask off you model for your non-slip surfaces.

It's really not a mystery formula, or am I the only one who's old enough to remember using old thick paint for filling fine seams on aircraft models?

It appears so Dave. :-) :-) :-)

I use the MS 1000 spray for priming assemblies with a lot of sanding(like a plastic main barrel), and the 500 with a brush. If you are using it to fill a seam, why would you want to spray an entire model with filler, it would ruin the detail. If you thin it, why not use the 1000 to start with I think regular Tamiya spray primer makes non-slip easier then either MS myself.

I guess thats my question too....should I be using this as a seam filler/checker or as a primer? I have to admit, I bought it before I knew what to do with it and figured I would find the answers here! :-)

I use the spray 1000 prime for a primer on parts that took a lot of sanding stick shaping and then final sand, such as a 2 piece barrell. I tend to use it more as a spot primer for joints more then the entire model. I re-prime everything with Tamiya spray primer before paint. I only use the 500 via brush over filler to get a smooth surface and to fill any pinholes, but I rarely use filler unless the kit is terrible. Most of the time on something like a barrel or jerry can, if you use just enough CA that it oozes out of the seam consistantly, you can file/sand it all down and need no filler at all. Something like an airplane fuselage seam is probably the best use for MS500. On round surfaces with two parts, like the jerry can or barrell example, CA oozed out of the joints 'cuts' well with sanding sticks and doesn't overheat with sanding like thick paint or MS500, or even some fillers can(where you get the slight 'bulge' of the paint/filler that never seems to sand all the way out).

Typically for something like DML tanks where the welds are on the edge of a part or on an inside corner, like on the bulge of a hull MG molded as a seperate part, the best filler is good ol' white glue with talcum powder added to thicken it. you just put it on a toothpick, put it liberally over the gap, let it sit for a few minutes(not too long, before it turns clear), and wet a swab in my mouth and smooth the seam. Fills small gaps without loosing ANY detail, nor needing any sanding. Works perfect for turret seams. If the part is already painted, it will dry clear and will 'carry' the color. Its used extensively on model ship building with superstructure joints to decks, both before and after painting.

Another little trick with CA is that for a small gap caused by something like a tab that overlaps into the side of a flat surface that needs to be sanded flat-when you sand it you notice the gap gets 'plugged' with sanding dust. You can leave that dust there, spread a little medium CA on it with a toothpick, wipe it quickly with your finger, let it dry for a few seconds, and sand some more. The CA will permiate the plastic dust, and as you sand it almost immediately turns into plastic filler that dries rock hard and sands smooth. totally alieviating using filler later. Not to mention its exponentially faster then filler.

Thanks for the detailed post kevin, that answered up alot of questions I had.

Sean