Sanding grit recommendations

[1970A-66Challenger]

For the amateur spraying in his home garage or shop, any advantage to single stage versus base/clear?

[70chall440]

I like single stage for its ease of use, however there is a lot to be said for 2 stage as well. Some have told me that with 2 stage you can make corrections along the way and get a better job overall. I cannot say anything about this as I have only used single stage.

[Mpdlawdog]

Ok so Ive been researching this to death here and on other sites....my car has at least two maybe three layers of paint (yellow/rootbeer brown)...Do I need to take it down to metal then self etching primer??  My car doesnt need any panels replaced or rust repair....the paint has some places where I sanded it down to the yellow looking for hidden bad body work and what not...nothing down to metal...and also some spots where it looks like a paint stripper got on the trunk lid and roof.....

If I take it down to metal...what do grit do I use?  I have an orbital sander and a 8 inch grinder with a hook and loop disc attachment...I know not to do too much with the grinder as not to mess the metal up.....ANY help would be great!!!

[70chall440]

if the paint that is on the car is ok (albeit ugly) you do not have to remove all. Take a car to bare metal is preferred because you get to see all of the problems lurking underneath it and take care of it. If you don't think there are any issues, you can scuff up the car, blend in any chips or flaking, fill any small dents or depressions, seal it with some primer and then repaint it (this is what many body shops do everyday). Many old school body guys will tell you that original or old paint makes the best primer... not sure I believe that but it depends on the vehicle and the previous paint jobs.

if you want to take it down or some panels down to bare metal, you can chemically strip it or mechanically strip it. I have used 120 grit (brown) flap wheels from HF to remove paint from panels, you just need a light touch and do not grind into the metal (just stripped my trunk lid this way). Fairly quick and IMO controllable. You need to be cautious around edges and corners. I like to use these wheels because they are designed for wood and dull up pretty quick when they hit metal, so the chance of damage to the panel is reduced, but they do a great job on removing paint. I use a 4 1/2" wheel because it is controllable. A larger wheel such as a 6" or even a 8" seem like they would be better but I do not believe they are; too much wheel spinning around.

Hope this is helpful.

[calicuda70]

I am also trying to tackle my 70 Cuda project myself one question I didn't see is, I have epoxy primed my bare metal what should I scuff the epoxy primer with before I apply the body filler directly over the epoxy or is this the correct step. thanks for the help!

James 

[70chall440]

Depending on the product you are using, you have a time window for epoxy before you have to either paint it (top coat) or scuff it and paint it. The product I am using is 5 days max; in other words if I shoot the epoxy and do not top coat it in 5 days, I will have to scuff it up prior to painting.

I highly recommend you obtain the product sheets for everything you are going to shoot onto the car; the sheets should show things like flash times, dry times, mixing ratios, reducing ratios/methods, etc. Every painter I know has a binder with these in them for reference. I built a book for this project with all of these sheets along with tips, directions, etc. since I do not do this often, I need something to refer to.

[MEH]

Heys guys GREAT THREAD!!!, it has answered some of my questions, and I have a few.
What media are you using to blast the car with?
After media blasting, I understand to wear glves and not bare hand touch the car, what prep are you doing to the bare metal? Wiping it a slovent to remove and media dust?
Are you painting the door jambs with the final coat prior to hanging the doors and fenders for alignment? If so are you using single stage or base coat clear coat?

[70chall440]

I cannot answer all of your questions because I haven't media blasted a complete car, however I believe your assertions are correct that you do not want to touch the bare metal after blasting. I did have a truck cab which the PO blasted and I had to wipe it down with wax/grease remover and blow it out extensively before coating it with epoxy.

as far as the door jams are concerned, I would think that if you are painting the car with BC/CC, you would do everything in that to include the jams. I know on my 2010 Challenger, the jams are not shiny like the don't have clear on them, but I am not sure. I guess you could shoot them in SS for some gloss but I suspect you would really need to mask it well.

[Cuda Cody]

Don't wipe sand blasted panels parts without taking a light DA to it.  The sand blasted panel will grab all the little hairs from the wipe.  Take a palm DA with 150 and go over the car lightly.  Then blow it off really good with air and then you can use wax and grease remover.  Blow it off really good after the wipe down too. 

The final color and paint you are using will determine how you'll want to paint the car.

[MEH]

Hey I plan on painting the Plum Crazy Purple, leaning towards the new color. I want to do a Base Coat , Clear Coat for the car. I have painted a Helicopter and a small plane before. Those I chemically stripped, did not use media blasting. I am leaning towards media blasting with walnut shells after I sand the body with a DA per Cody's recommendations.

[EbodyMod]

The weather is pretty nice on that side

[Cuda Cody]

Media blast first, then a light DA.  The DA is only to knock out any left over material that the blasting may have left in the metal and to smooth out the metal so you can clean it.  If you try to wipe the blasted panels you'll find out real quick why I go over them with a light DA sanding.  Without the DA it's like trying to wipe off sand paper. 

These are the gloves I use to touch the bare metal.  But any like these should work fine.  Just don't touch bare metal with you bare hands.

https://microflexpublic-ansellhealthcare.msappproxy.net/Products/MF-300.aspx

Paint is extremely fun and with few tips and tricks you can achieve show quality paint in your garage.  I'm going to try and find time to do a how to video next year.

Hey I plan on painting the Plum Crazy Purple, leaning towards the new color. I want to do a Base Coat , Clear Coat for the car. I have painted a Helicopter and a small plane before. Those I chemically stripped, did not use media blasting. I am leaning towards media blasting with walnut shells after I sand the body with a DA per Cody's recommendations.

[HP_Cuda]

Ahh the old cushion on the stool for the sand blasting cabinet. I stand most of the time but in the end it cranks on my back since I'm friggin tall.