Cutting compound and racing strips

[gordonli1]

Hi, Ive got a quick question regarding cutting compounds and painted racing strips.
Do I use the cutting compound before or after clear coating the model? Also if I use cutting compounds, will it rub some of the paint from the racing strip and mixes with the car's body paint?

Primer -> Body Paint -> Racing Strip -> Cutting compound -> Clear coat-> Wax?

or

Primer -> Body Paint -> Racing Strip -> Clear Coat -> Cutting Compound -> Wax?

Any input would be great!
PS - The body colour is acrylic Tamiya Metallic Grey (XF-56) with gloss black strips

[stevetriumph]

You are going to get a slight step along the sides of the racing stripes. If you don't try to rub these down, you will see the step after you lay the clear coat on.
I would recommend using very fine wet and dry (micro mesh) gently along the edge of the stripes to eliminate the step. Experience will tell you when you have got it right and others will tell you their own methods.
Beware when using abrasive materials on metallic paint as it can cut the metallic particles and cause flat spots in the paint which show through clear coats.
Hope this helps,
Steve.

[gordonli1]

Hi steve, thanks for the reply, i was thinking along the same line as you but wasnt 100% sure...
Ive just finish laying the base colour and will be masking the stripes. At the moment, there isnt any orange peels and I intend to leave the base paint as it is, after all, abrasive can leave flat spots like you said.

PS - I did use more thinner than usual, approx 60:40 thinner to paint ratio to avoid orange peels

Next step will be masking and painting the stripes, then clear coat and finally cutting / polishing. Lets hope there wont be any big dramas

PPS - Thanks again for your input!

[stevetriumph]

Good luck with it, take your time and use a good quality tape that seals well. Should be fairly straightforward.
Good work on thinning the paint, orange peel = hard work lol.

Steve.

[corvettekid_7684]

You can help eliminate the edge of the painted stripes by masking the striped area off, paint the base color, and then mask again the base color for stripe painting. Then carefully polish down the edges, touch up as required, polish, then clear everything. That's how I did my Airwolf model anyhow, except I didn't clear it at all...

[Didymus]

You'll get have better control if you wet sand with 1500 or 2000 grit wet-or-dry paper.

Many automotive compounds - like the Dupont Red and White compounds - are much too strong for modeling applications. After the wet-sanding stage, I'd suggest Tamiya or Novus compounds. They come in a range of strengths; even Tamiya Coarse is nowhere near as coarse as the "fine" automotive stuff.

[gordonli1]

Thanks for the input, ive since sanded the areas carefully with 2000grit wet paper and finished unmasking the strips after spraying, the car was mummified so i can spray in 1 go.
Results was good, albeit there is a tiny over spray due to the masking tapes that wasnt 100% aligned in the overlap, i might touch it up abit with black paint, but at the moment, its hardly noticeable unless you look really hard.
I plan to use the tamiya 'Fine' and 'Finish' compound after clear coating it.

[corvettekid_7684]

You might be able to carefully sand down the oversprayed area also...

[gordonli1]

Originally Posted by corvettekid_7684

You might be able to carefully sand down the oversprayed area also...

Thanks for the comment, I didnt dare to sand any more areas down as there are some flat spots with wet sanding, its only noticeable in direct sunlight, but not in fluorescent lightings. Mostly in the bonnet (hood) section, thats where i did my trial with wet sanding.
Not sure what I will do yet, most likely, going to strip the paint and respray the hood since its more practical and i will have a more uniform metallic grey instead of a few shades of metallic grey.

As for the overspray (more correctly, it was under-spray in 1 side of the strip by approx 0.1mm), ive since masked off the surrounding area and resprayed the gloss black, resulting in a very convincing and perfectly aligned stripes now

PS - But i did made a rookie mistake, i masked off the area of the under-spray before the paint was completely 100% dried, (it was 95% dry), and when i lifted off the masking tape, some of paints in the main strip was lifted off..bummer but easy fix anyway