marks/stains on model

[keveuh]

Hi everybody, I'm having the weirdest problem here with my model.
I'm building a Tamiya 2CV, which was painted (the body) with Alclad primer - Zero TS-44 blue - Tamiya TS13 thinned with Mr hobby levelling thinner.
All went ok, I then sanded and polished.

During the polishing session I saw some marks while I was polishing, like finger prints and stuff like that. I thought that was due to the polishing compound remaining on the surface and because of the pressure with my fingers while handling the body it left marks. At some places though polishing made the surface become kind of a tiny bit more "dull" I thought that was because of the polishing cloth I was using (same as always by the way and never any problem). Anyway I went carefully to polish the rest of the body and eventually it went fine. I then washed the body and let it dry a whole day.

Now to day I went ahead and tape the body for further painting and there this evening I saw some new marks again !!! I try to remove then with a soft cloth = doesn't work. Water + qtip = no, window wash + qtip = no, qtip = no, tamiya wax = no. Nothing seems to work excpet if I polished I guess but that shouldn't happen. It's the first time I have this problem and I cannot find the cause of it !!!






What do you guys think ? I did have my hands cleaned every time, could it be the soap I use to clean my hand ? A problem with the varnish I used (tamiya ts13) ? Or what ??

It causes me quite some problems because right now it's like I cannot touch the body without leaving marks ! And the varnish has been drying for at least 2 weeks, I didn't count but I guess I could safely say it even dried for 3 or even 4 weeks.

If you have any advice or help feel free to answer !

Thanks a lot !!!!

[freakray]

What kind of soap did you use to clean the model before priming? Some soaps contain oils which can stay on the model surface and effect the paint.

Also, how much time did you allow the model to dry before you handled.

As a side note, TS13 is a pretty questionable quality clear and dries notoriously slowly.

[keveuh]

I always use the same dish washing soap when I clean my models and those stains I talk about appear it seems when I touch the model with my fingers or if I wipe it with a cloth.

I let the model dry at least 2 weeks (but certainly more I don't remember) before starting to sand and polish.

Might it be that it's nor fully cured and therefore it leaves stain on it ?In that case how long to wait ?

[freakray]

Then the obvious answer is what you've already identified, it's oil coming off your hands. Once you've washed the model, handle it as little as possible and always wash your hands before you handle the model.

[keveuh]

Oil from my hands ?? I know the skin produces "fat" or "oil" but I've never seen that before on any of my other models !!

I'll try to wear gloves next times and see, and if it still happens I'll wait an extra week for the paint to dry, even 2 weeks if needed. If the problem still occurs I might want to repaint it (for the 4th time maybe) but with a spray can this time. Because that's the first model I paint with my airbrush and my other models painted with spray cans never had such problems.

Thank you anyway.

[Citroen TA]

Using vinyl or cotton gloves when touching the model helps a lot.