Dean Jenkins
Promoted Users
Many people are interested in using the @Jim C method for cutting and buffing. Jim has been very gracious and helpful to all of us who ask for his advice.
The "Jim C. method" is mentioned in several threads. And, he has updated it over time. It is hard to find a simple, current summary of this method.
I offered to interview Jim and to capture the current method. He was kind enough to agree. We had a great conversation and here is what I captured.
Maybe this can be a "sticky link" if people find it useful.
The Jim C. Method
This process assumes that all final Clear or Single Stage coats are done and are properly cured.
Cutting:
The purpose of this step is to remove any orange peel or trash from the surface and to get it flat.
He does it dry because you can see what you are doing. Wet sanding does work, but you have to squeegee it off and catch the light just right etc. to see what is going on.
When you do it dry, you can see what is going on with the surface as you are sanding. Peel, trash etc. are clearly visible when dry sanding.
Jim uses 1000 grit to get about 80% of the peel and trash worked out and then stops. This is because trying to get 100% with 1000 grit will leave scratches that are hard to get out later.
Next to go to 1500 grit – DRY. With the 1500 grit, get the remaining peel and trash worked out. The 1500 grit scratches will be easier to deal with in subsequent steps.
Dry sanding for the same reason listed in 1000 grit.
Buffing/Polishing:
The purpose of this step is to refine and remove scratches from the previous steps. It is NOT to do any leveling or removal of defects. If defects are discovered, you have to go back to the cutting stage to resolve them.
Jim starts with the Eagle Abrasives Blue Bufflex 2500 finishing film discs. He does this WET (yes, Eagle specifies DRY, but WET works better and the discs last longer this way,) on a DA with a soft interface pad.
Jim likes to go over the entire project TWICE with the 2500 Bufflex. He has found that it is inevitable to miss some spots or have scratches from previous grits still present, so he just does it twice and that ends up saving time.
He uses 3D ACA 510 compound on a rotary buffer, at 2000-2200 RPM.
Final step is polishing. This is done with a Black Foam Pad (again, no preference here.) Compound is 3D ACA 520, on a rotary buffer, at 1200-1400 RPM.
**Some people like to do a final polishing step with 3M Ultrafine on a light blue pad. Jim has tried that and for the projects he is doing didn’t find it added anything. But, if he were doing a black show car, he thought it might be helpful.
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I have also put together a page on my website with links to the materials that Jim uses, and some additional ideas for tools and supplies, on Amazon.
Here is the link:
blackdiamondblocks.com
**In the spirit of full disclosure, I am part of the Amazon Associates program and may earn a commission on any sales. But, I only link to products that I have used and am fully confident in.
The "Jim C. method" is mentioned in several threads. And, he has updated it over time. It is hard to find a simple, current summary of this method.
I offered to interview Jim and to capture the current method. He was kind enough to agree. We had a great conversation and here is what I captured.
Maybe this can be a "sticky link" if people find it useful.
The Jim C. Method
This process assumes that all final Clear or Single Stage coats are done and are properly cured.
Cutting:
The purpose of this step is to remove any orange peel or trash from the surface and to get it flat.
- If the project has graphics or stripes etc. and you’ve put extra coats of clear on them to “bury” them, 800 grit can be used to level these areas out, carefully.
- If this is a full vehicle project and you want to get it as flat as possible, then 1000 grit on sanding blocks is the way to do it.
- Or, if the final finish didn’t come out really flat (urethane wave, excessive peel, or trash) and you want to get it flat, then blocks are the way to go.
- If you did the “SPI Perfect Paint Job” 2-step process of initial coats of clear/single stage, block it with 600 and then follow up with a few more coats, it should be pretty flat, and you can use a DA with a soft interface pad to get any minor peel or trash worked out.
He does it dry because you can see what you are doing. Wet sanding does work, but you have to squeegee it off and catch the light just right etc. to see what is going on.
When you do it dry, you can see what is going on with the surface as you are sanding. Peel, trash etc. are clearly visible when dry sanding.
Jim uses 1000 grit to get about 80% of the peel and trash worked out and then stops. This is because trying to get 100% with 1000 grit will leave scratches that are hard to get out later.
Next to go to 1500 grit – DRY. With the 1500 grit, get the remaining peel and trash worked out. The 1500 grit scratches will be easier to deal with in subsequent steps.
Dry sanding for the same reason listed in 1000 grit.
Buffing/Polishing:
The purpose of this step is to refine and remove scratches from the previous steps. It is NOT to do any leveling or removal of defects. If defects are discovered, you have to go back to the cutting stage to resolve them.
Jim starts with the Eagle Abrasives Blue Bufflex 2500 finishing film discs. He does this WET (yes, Eagle specifies DRY, but WET works better and the discs last longer this way,) on a DA with a soft interface pad.
Jim likes to go over the entire project TWICE with the 2500 Bufflex. He has found that it is inevitable to miss some spots or have scratches from previous grits still present, so he just does it twice and that ends up saving time.
- After the 2500 grit, Jim makes a judgement call. If the clear is relatively fresh and has cut well so far, he proceeds to the next stage with a wool pad.
- If the clear has cured longer and is harder, he will use the 3M 8000 Grit Trizact foam pad before going to the wool pad.
He uses 3D ACA 510 compound on a rotary buffer, at 2000-2200 RPM.
Final step is polishing. This is done with a Black Foam Pad (again, no preference here.) Compound is 3D ACA 520, on a rotary buffer, at 1200-1400 RPM.
**Some people like to do a final polishing step with 3M Ultrafine on a light blue pad. Jim has tried that and for the projects he is doing didn’t find it added anything. But, if he were doing a black show car, he thought it might be helpful.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
I have also put together a page on my website with links to the materials that Jim uses, and some additional ideas for tools and supplies, on Amazon.
Here is the link:
Finishing Grits | Black Diamond
blackdiamondblocks.com
**In the spirit of full disclosure, I am part of the Amazon Associates program and may earn a commission on any sales. But, I only link to products that I have used and am fully confident in.
