Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Sounds like a good plan, I usually use 180 for blocking, just depends on how good the bodywork is. You should use a variety of blocks for different contours-panels, I like the Durablock that is around 20" . Reguidecoat and sand with 400-600 wet. I use 400 but always use a sealer. I also prep the whole car with a grey scotchpad and Scuff Stuff (Ajax will work) doing one panel at a time and rinsing with a hose, kinda messy but REALLY cleans the car. Good Luck

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

I think I will BLOCK (DRY) the ELKY first with a 10" hard rubber block fitted with 220 grit. Then (WET) Sand the Elky with 400 wrapped around a hard 3M rudder pad. My questin is when do I use the GUIDECOAT ??? When im DRY sanding with 220,or when im wet sanding with 400 ??? I want to say when im DRY sanding with 220. Is this CORRECT ??? Mark

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

I spray some cheap black on to guidecoat the first time with 180-220 then use 3M's dry guide coat before the 400. But you should guidecoat each time you switch grits.

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

use 3M's dry guide coat before the 400.

Is that the powdered stuff?

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Make sure you use a laquer product for a guidecoat. DO NOT USE AN ENAMEL BASED PRODUCT. It will gum up the sandpaper. I do all the bodywork in 80, then finish in 180. After that, I use a grat laquer primer and block the car with 220. Once I'm happy with it, I go prime it again, then dry block it with 320 or 400. After that, I use an epoxy primer/sealer and block that with 400 wet, then paint.

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Yep:thumbsup:

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Ok, so you got everything primed. heres whats next.

You want to put plenty of primer on the car to start out with. after that guide coat the whole car " black spray paint will work" just dust it over the primer . next use a long block and 180 grit paper, and sand as much of the flat spots on the car useing the long block. this will show you where any high or low spots are that need repair befor the next step. finish sanding the primer until all the guide coat is sanded off. the car is now ready for its second coat of primer. this coat dosent have to be as thick as the first coat, because the car should be flat. after the primer is layed guide coat the whole car again. next useing a medium block wet sand the whole car with 600 grit. you may need to use some different sanding blocks and pads to get in the tough spots. DONT SAND THE CAR WITH JUST YOUR HAND! always use some sort of block or pad. if you dont you will see groves in the surface from your fingers digging in. "this is called finger ****ing the car". ok after the car is sanded with 600 wet, check over the whole car for pin holes, if there are some pin holes sand a small spot around the pin hole with 320 "Barely scuff it" then fill the hole with glaze or putty. the sand it flat with 600 wet. after this the car sound be cleaned and blown off. then it can be painted.,

I hope this was good enough directions. I follow these same steps when i paint $150,000 cars every day. www.Uniqueperformance.com

David Farmer

Daveindachevelle@yahoo.com

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Dave, THANK YOU very much for all that GOOD information. I just have one question: I sprayed 2 heavy coats of PPG NCP-271 Urethane Primer-Surfacer on the entire Elky and here is my question : After I long Block the Elky with 180 ,if its FLAT enough, couldnt I just WET sand it after that using a hard rubber pad fitted with 600 and not shoot any more primer on the Car ? Im out f NCP-271 anyway and that stuff is really expensive. I allreay have about $2,500.00 in paint supplies allready. Please let me know on this matter. Thanks Again Dave, Mark

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

If you can 180 it and get it straight with the primer you have, you could re-guidecoat and go to 400-600. I doubt 2 coats will be enough though, only one way to find out, try it and maybe you can get away with just spot-priming some small areas.

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

You have a lot of great info here to go by. It sounds like you got a good head on your shoulder when it comes to preperation, so don't skimp in the end because of a few more dollars. You will be sorry if you do. Besides you can alway store the extra for your next project because we all have more than one project. Can I get an AMEN.

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

You have a lot of great info here to go by. It sounds like you got a good head on your shoulder when it comes to preperation, so don't skimp in the end because of a few more dollars. You will be sorry if you do. Besides you can alway store the extra for your next project because we all have more than one project. Can I get an AMEN.

I agree, re-priming would be the best way to go, but if money is a problem ya gotta do what ya gotta do Good Luck.

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Sorry about the long reply. iv been so buzy at work. anyways if and only if you have enough primer to work with on the car can you re guide coat it and wet sand it. here is the problem with doing that. if there is not thick enough primer you will have sand throughs. small sand thews are ok, like on body lines and in tight places. but you will end up with very big sand thoughs all over the car as you cand all the 180 grit scratches out. this might not look bad at the time it will still be slick as glass. BUT when ever you spray the car with base coat you will see a veriation in the color where the sand throughs are. they will look like dark spots in the paint and they will never go away. BUT there is one more trick up my sleave... if you dont want to reprimer, guide coat the car again, wet sand it with 600 dont worrie about the sand throughs just sand off all the guide coat. THEN when you areready to paint the car, Find out what brand of paint you are going to use and call and get "SEALER". this is like primer but it self levels over the car and give it a uniform base to spray on this will also provide a better bond in between the primer and the base and clear resulting in a paint jub that will last longer and have no veriations in the color. just make sure you use what is recomeded by the brand of paint you are useing. call and ask them. if you dont the paint might not bond correctly and might delaminate or a bad cemical reaction could occur. you get the picture. just thought i could save one paint job from failure every once in a while. if you have any more questions just ask.

David Farmer

Uniqueperformance.com

My ride. 1970 chevelle SS "clone".

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Sorry about the long reply. iv been so buzy at work. anyways if and only if you have enough primer to work with on the car can you re guide coat it and wet sand it. here is the problem with doing that. if there is not thick enough primer you will have sand throughs. small sand thews are ok, like on body lines and in tight places. but you will end up with very big sand thoughs all over the car as you cand all the 180 grit scratches out. this might not look bad at the time it will still be slick as glass. BUT when ever you spray the car with base coat you will see a veriation in the color where the sand throughs are. they will look like dark spots in the paint and they will never go away. BUT there is one more trick up my sleave... if you dont want to reprimer, guide coat the car again, wet sand it with 600 dont worrie about the sand throughs just sand off all the guide coat. THEN when you areready to paint the car, Find out what brand of paint you are going to use and call and get "SEALER". this is like primer but it self levels over the car and give it a uniform base to spray on this will also provide a better bond in between the primer and the base and clear resulting in a paint jub that will last longer and have no veriations in the color. just make sure you use what is recomeded by the brand of paint you are useing. call and ask them. if you dont the paint might not bond correctly and might delaminate or a bad cemical reaction could occur. you get the picture. just thought i could save one paint job from failure every once in a while. if you have any more questions just ask.

David Farmer

Uniqueperformance.com

My ride. 1970 chevelle SS "clone".

Agreed, I almost always use a sealer, never a chance of sandscratches, color also covers easier over uniform color. You can seal over 400 scratches easily.

 

Re: What Grit Sandpaper,and Correct Sanding Technique To Use To Be Ready For Paint ??

Don't use anything courser than 320 grit. 320 or 400 will work.