5 replies to this topic

[Jase]

Whilst I like to do all of my painting myself I will only use cellulose because it was the original type of paint used plus it is very forgiving for an amateur like me.

 

I'm painting the inside of my car at the moment and I really don't want to be cutting the coats back inside the car as most of it will be covered with sound deading sheets anyway.

 

Any tips on how to get a ggod finish on the final coat straight from the gun? Would you go for a 40/60 thinners split?

 

Or can I coat in a clear coat that I see many people using over a base coat?

 

Just looking for hardwearing solutions.

 

I'll stick with the good old fashioned process with external panels.

 

Thanks

[weef]

Hi, cellulose gives a good finish out of the gun. I usually start with a 60/40 paint to thinner ratio and build up the cover on the panels until the opacity looks right. Allow time for the solvent to flash off between coats. Flat down the surface as required and progressively increase the thinner content as you apply further coats, observing the finish from the gun will tell you how your doing.

Once the finish is to your liking and you really want that high gloss from the gun its a 90/10 thinner to paint ratio that is required to bring the shine up. You have to work fast with this coat and its always a twitchy time. After the final coat has been applied it does take a time for all the solvents to flash off and the surface remains "soft". 

Don't be tempted to really lay the paint down too heavy as the trapped solvents take a time to  flash off and this can lead to paint surface problems.

I would not say that using cellulose is "very forgiving for an amateur". 

[bluedragon]

Another factor to take into consideration is the type of thinner (reducer) used. Usually for automotive-quality paint of this type, there are several types of reducers for specific temperature ranges.

 

If you choose a "fast" (low temp) thinner in hot temperatures, it can dry with a rough or matt surface because the reducer evaporates too quickly, not letting the paint flow out smooth before it dries.

 

If you choose a "slow" (high temp) thinner in cold temperatures, it can end up dripping and running, or worse softening and dripping the previous coats, because it takes too long to evaporate. It doesn't harden before gravity starts taking effect on the wet paint.

 

You can use a clear coat. In fact I'd recommend it for use in an interior. But it doesn't make things easier. If you end up getting a flat looking (but not rough or pebbly) color coat, a clear coat would give you another chance to get the shine back. But if it's rough and coarse, you'll have to sand it down and flatten it.

 

 

by the way for the hardest, more durable finish resistant to wear, you should be looking at a chemically hardened enamel or better yet a 2-pack urethane (if you have the safety gear to spray it.) You can even just spray a 2-pack clear though most vendors won't guarantee that.

 

 

Dave

Edited by bluedragon, 13 October 2019 - 10:39 PM.

[Jase]

Thanks Dave, I have the kit but doing this in the garage with neighbours hence the use of cellulose plus the reasons above. My paint supplier only sells one type of thinners now so may have to look elsewhere. Thought it might be a good idea to use anti blooming thinners this time of year?

[Hedgey]

One thing to consider if spraying cellulose over old paint is reactions. Especially if using a lot of thinners. 

I'd be tempted to use epoxy primer (2 pack but not iso) which is very hard wearing and can be sprayed over with the celly. In the areas which you might see you can flat the epoxy back for a good quality finish.

 

You can even use the epoxy 'wet on wet' which makes it very quick 

 

Elliott

[Jase]

Thanks Elliot, okay with regards to previous paint. I'm painting onto a brand new shell so no reaction fortunately.