Sanding between coats of clear
I read an article that said sanding with very fine (1000-1500) paper between each coat of clear would give show quality results. Does anyone here do this? Also what do you do about dust nibs in between coats? Do you try to sand them out and if so how do you ensure that "flat" spot doesn't show up after the next coat is applied?
If you need to wet sand the clear, DEF use nothing coarser then 1000. Reason being, the clear most likely isnt completely CURED, although it may be dry enough to sand. Anything coarser could cause deeper scratches then you want and could possibly show through your next coat(s) of clear.
Originally Posted by RAJs39LaS
As for the nibs, the best option is to block sand it until the spot(s) where the dust is/are disappear comletely, or atleast until MOST of them are gone. Realistically, if the dust is down in your first coat, your going to burn the clear to get ALL of it out. you basically want a smooth finish that doesnt appear to have huge patches of fish eyes. when you lay your clear, it should fill and cover all of the scratches and the small areas where dust may till be trapped.
Another possible solution is to use a prmium HIGH SOLIDS clear. High solids clears were designed to have a higher gloss then standard clear....think of it this way:
regular, medium solid clears are used for collision repairs, small jobs, and universal clearing...nothing rediculously fancy as you dont want it to stand out from the rest of the vehicle.
HIGH SOLIDS clears on the other hand are formulated to have a higher gloss...if you paint two vehicles the same color but clear them each with the two individual clears, 3 coats apiece, you will SEE a noticble difference in the gloss. High solids clears will give an almost glassy shine when properly sprayed. With HS clears, you can achieve the same shine with 3 coats that you would have to do what you are now doing, reapplying clear, to achieve that same shine.
What manufacturer do you plan on using? if i havent used them before, ill do some research and tell ya what i personally would recommend trying to save ya a little money.....
you need to re read the article.
I almost completely disagree with Bunky. most dust is colorless. I ignore it untill I color sand. I never have to dig it out of the 1st coat of clear. I use HS clear for everything
i agree with that...dust IS colorless...what i look for when i take it into the light is the HIGH spots...if you inspect the job at every possible angle, you will most likely SEE the dust sitting higher then the rest of your clear. as for digging it out of your first coat of clear...remember...i dont know you or how you spray. i have worked with some painters who can lay ONE coat of clear on, and as long as there isnt alot of dust, then the customer will never notice and it doesnt have to be wet sanded a buffed.
Originally Posted by 88GT
This, in my opinion, should ONLY be done for a cheaper job, one that you are forced to cut corners, and even I will not let a car go with less then two coats for better UV color protection.
But as i said before, i dont know if this is something that YOU do (and NO i am not making assuptions about you, i am pointing something that SOME painters do and i know it isnt right and it wont last.)
maybe i misunderstood your question though. as for the show quality, yes, more clear can giv it a better gloss, even using your high solid clear.maybe i went a little further then your question by mentioning the dust part.
the article was probably about flow coating. 2-3 coats, let it cure, sand with ??? 1000 or so and clear again. Waste of time and product in my book.
You dont touch clear while you are applying your 2-3 coats (with very few exceptions) There are tools for those exceptions.
as far as dust, some dust gets bretty burried in clear if its deep enough and needs little to take care of it. I color sand almost everything I paint besides bumper covers, and yes I use 2 coats of HS clear. Not 3 unless for some strange reason I need a third coat.
Never too much information. All is appreciated. As far as the brand, I am using PPG's Shopline brand and the paint jobber is recommending high gloss JC-661 clear. I thought the same way about dust not being noticable and when color sanding it would level well enough to not be noticable, however, the article was from a restorer's guide book and I had never heard of anyone doing the sanding. Just thought if it was worthwhile then I woudl try it for my resto.
I think you will be just fine applying 3 coats and doing a good job color sanding and polishing. IF you get something you can see (bug, dirt etc) in the 1st coat of clear, you will want to carefully remove it imediately. Burying it wont do any good. The later in the clearing session, the better your chances of it sanding out. If it gets on top of the last coat and doesnt manage to sink much, drink a beer and relax
Originally Posted by RAJs39LaS
to tell ya the truth, the guy from Finish Master that im friends with came to the shop the other day and was telling me about the Shopline and how it is comparable, price wise, to the Matrix i am used to using. We actually HAD the DBC intermix system for a while along side the Accushade Intermix system to do a price comparrison...DBC wound up being twice as much, so we stuck with Matrix. Im thinking as far as that goes, his overhead told him to stop in and try to get us back as a paint customer.
That being said, i will actually look into the Shop line, now that I know people ARE using it. I will be looking for another shop to paint at real soon so it always helps to know about as many paint lines as possible so that you can move into a new shop and not have to learn their system from scratch....
OK, so i think i got a bit off topic there for a minute.
Just read the tech sheet for the 661...actually it sounds like a very good HS clear, comparible to PPG DC2002 (i think thats their universal HS clear, could be wrong, its been a while since i used it). to tell ya the truth i think 88GT is right when he says that it is a waste of material to lay MORE clear onto your project because this is designed to give a high gloss with only 2-3 coats. Any more would be overkill and i really dont think it will give any better GLOSS, just MAYBE longer UV protection (if thats even possible, i honestly dont know)
Originally Posted by RAJs39LaS
Thanks for the advice. If drinking a beer and relaxing helps then I've got nothing to worry about!!
As far as the Shopline brand's performance I'm new to this and can't tell you much but so far with primer application and paint prep I have been very pleased. Even where I made mistakes with the application it was very forgiving and I have not had any problems with adherance. I've had numerous local shops tell me that they have tried other brands and they return to PPG. They agree that the Shopline is less quality than the PPG paints but PPG makes it and they still strongly reccommend it. Also it is less than half the price. Guess you got to decide how much performance you want and how much your willing to spend.
Ok Im going to go drink a beer now... paint gets me so uptight.
Yep, that's not unusual. This is why I recommend that you do all of your prep work the day before so that you only need to do a little cleaning prior to mixing your paint and spraying. Much less stress and a faster path to the beer.
Originally Posted by Vette Mech