Thread: Hey SPRAYTECH...I need some advice please

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Need some advice, and lets assume all product's are compatible, O.K. being the novice I am and putting 12 to 13 hours a day in at work puts some limits on my body work so my delema is this, Got the roof all dinged & pinged & ground down pretty good over the weekend,but it'll probally be the next weekend for I can get back to it and I know some oxidation is gonna start back before then even though its in a garage, so heres a few questions if'n ya can help me out
1.. can ya spray epoxy primer/sealer in sections i.e. roof then sides etc. as ya get to em ?
2..reading all your posts I know I can do the bondo work over the sealer long as I ruff it up, Butttttt how rough for a good bond ?
3..Can I spray regular old laquer primer over the epoxy for the final blocking process or will that lift the epoxy ?

# 1 question is yes you can do it this way, its a good idea to go this route when time is limited.
one panel at a time till its all in first coat of primer.

#2 , I usually will grab a piece of 180-220 grit and hand rough the repair area up pretty good.

#3, That is a good question and have forgot if lacquer is reccomended over epoxy, i will have to check.

(Might check with your jobber of the product you are using to make sure about compatibility.)


Spray

Appreciate it...... Thanks

I am not Spray Tech, but I do have an answer for question #3. I just finished painting my Dodge Challenger using DuPont 615 VariPrime as my base. When I block sanded, I used a very light dusting of good ol' 80S red oxide lacquer primer for my guide coat, with perfect results. I think SEM makes a guide coat specific primer if you are still concerned, but I know even House of Kolor systems use lacquer guide coats over their epoxy primers. Good luck. Brian

well first of all, you shouldn't use bondo over sealer, its a waste of sealer, sealer should only go on after everything is straight and ready to paint, you should'nt ever use sealer until the day you're ready to paint.
Spray tech is right, you can do it panel at a time, as a matter of fact you should always do it this way, otherwise you over burden yourself by trying to get the whole car done at the same time, you will get more stressed out and seem like your project is going nowhere. You also said primer/sealer, these are two completely different things that have different purposed, like i mentioned earlier, a SEALER should only be used after everything has been straightened and blocked to 320, and you're ready to paint within 48 hours. I do not know what system you are using but if you are using PPG then you should get ncp271, you can spray your panels one by one, its a primer and a primer surfacer all in one, but it smells like shit when you spray it, so get a mask. It will protect from any corrosion or moisture until you are ready to paint, but then you should get everything in the frist coat of 271 and then block the whole car down all at once, using a 3M Guide Coat system for best results....now if you aren't using PPG just forget everything i've said, except for the first paragraph

hmm, well i got into this forum on accident with a search engine, i just noticed its al all hot rod talk area forum, so your probably all using laquer paint so..dont take my advice, lol

1.sand to bare metal
2.prime w/PPG'S epoxy primer
3. wait overnite if you use 2 coats of primer
4. apply plastic filler directly to the primer. You do not have to skuff unless you wait 1 week.

Get PPG'S product info sheets & read before proceeding.

I guess my post was deleted.

do not follow don meyer's instructions, use your body filler BEFORE you primer, it is best used on bare metal. Grind the surface with a 24 grit sanding disc and apply your plastic, use fiberglass resin to get a smoother easier to sand finish. Sand with 40 grit sand paper, do not use any higher than 80 grit, prime with DP epoxy primer and it will help fill the 40 grit sanding scratches, then spray with ppg's K36 primer surfacer. This will be the easiest way and will turn out the best. But it will cost more for DP and K36, There is another option which is ncp271 also made by PPG. It is a primer/primer surfacer, does the job of DP and K36 at once

Well I 4 one have been using PPG's products for 30 years PROFESSIONALLY , and have been to about every PPG refinish school and am Platinum certified
ALL LEVELS................
You might want to go to one mgbgt as PPG STILL reccomends using DP/DPLF sprayed over BARE metal then Apply the bondo over that !
Then you can spray K36 or NCP 271 ( which I have used since it came out 5 years ago.)

AND adding fiberglass resin to your bondo is NOT reccomended but the HONEY specifically designed for bondo is for a smoother spread out.
I have my body men cut their bondo down with 80 grit then apply a thin layer of glazing compound over the bondo repair then cut it with 180 grit.
This will insure with having to use many layers of primer for filling and less shrinkage !

SPRAYTECH

Originally posted by mgbgt
..dont take my advice, lol

That may be the most accurate thing you've said since you got here!

i have been to PPG's refinishing school, and when they say spray DP over bare metal, they dont mean dont spray over bondo, they mean you shouldn't use DP unless you have stripped the entire car down to bare metal, like as in, dont use it for spot repairs. you should ALWAYS apply your bondo to bare metal, it adheres better. you also need to feather edge your work, if you apply bondo over DP or a paint edge then it only raises the surface, you make more work for yourself. Then when you sand the bondo you will sand down the freshly sprayed DP around the edges of your plastic work and then you just wasted product, time spent spraying, time spent cleaning your gun. its a watse of everything, and if you use bondo before spraying DP the DP helps fill the scratches. so you dont need many coats of your primer surfacer

DP/DPLF has Higher Bite properties to Raw metal then body filler, therefore PPG reccomends it down first then your body filler, this why you dont have such deep scratches to fill on your repair , and it useless to use DP/DPLF as a sand scratch filler , THATS NOT what its designed for !!

I am not saying your way wont work as its been done that way for years with no ill effects. But PPG
still wants protection between your bare metal and body filler.

We are on a HOTROD building forum where doing it right with no time frame on getting it out the door quick is not the subject.

I dont do the way i posted at my shop as it is VERY time consuming, I let my body men grind and fill over bare metal too , as time is of essence, and I use NCP 271 over the repair as it has metal etching properties built into this product. But I dont let them send the repair to me in anything courser then 150 grit, as this is where time in the paint shop is , as it requires too many coats of primer or a block and reprime . Time wasted and product waste.

Spray

HWORRELL,
Tech has it right, the only thing I could add is to make sure to treat your bare metal really good as contamination is the number one cause of paint failure. Just get it clean, and keep it cleaned down as you go...Don said it too....get the tech sheets from your supplier. Good Luck