Main Menu

Cut and Buff

Started by Cuda Cody, December 29, 2016, 02:25:42 PM

Previous topic Next topic

0 Members and 2 Guests are viewing this topic.

Cuda Cody

The next car I paint I think I'm going to do a step by step cut and buff video.  I bought a paint gauge this year so I can keep track of how much clear each cutting step removes.  I've never cut through clear, but it's something that always worries me.

303 Mopar

I don't have the skills or patience to do any body or paint work.  However, I admire the heck out of those that do and you @Cuda Cody are an amazing talent!   :worship:

Spikedog08

Quote from: 303 Mopar on December 30, 2016, 04:16:20 PM
I don't have the skills or patience to do any body or paint work.  However, I admire the heck out of those that do and you @Cuda Cody are an amazing talent!   :worship:

I totally agree!    :ohyeah:
Drive it like you stole it . . . And they're CHASING you!


Cudalbs

Ooooo Noooo to late, I'm cutting and buffing my wife's car and CRAP, went through on the drivers side door.  :Thud:  Hope that video gets made pretty soon. Might want to throw in clear coat repair lesson too, haha.
"Love those round taillight cars"

Cuda Cody

Did you cut through near an edge?

Quote from: Cudalbs on March 05, 2017, 08:27:19 PM
Ooooo Noooo to late, I'm cutting and buffing my wife's car and CRAP, went through on the drivers side door.  :Thud:  Hope that video gets made pretty soon. Might want to throw in clear coat repair lesson too, haha.

Cudalbs

Yes I did, the bottom corner. The door is not completely flush with the pillar and I was sanding across both of them, (rookie mistake) and that corner cut way to fast and boom. Clear and paint went in one swipe. Does it sound like it can be spot repaired?? Not a classic car, it's and 2003 Acura TL with less then 100,000 miles on it and the paint was oxidizing so we decided to paint it rather then sell it.
"Love those round taillight cars"

Cuda Cody

Clear is super thin near the edges because as it dries it pulls back... so edges always end up with a lot less clear.  It's a good habit just to tape edges and hard lines so you don't burn through.  It can surprise people how fast you can burn through clear near the edges.

Unfortunately there is no easy quick fix.  They make blending chemicals that basically melt the clear so you can blend in new clear with the old, but it can be tricky to do and takes practice.... plus it never really looks perfect.  Without seeing it I'm not sure there's much I can offer in terms of tips.  And even if I could see it I'm not sure there's much I can do to help either.  Could you have the guy that painted it take look and see if he can blend it in?


usraptor

Quote from: Cuda Cody on December 29, 2016, 02:25:42 PM
The next car I paint I think I'm going to do a step by step cut and buff video.  I bought a paint gauge this year so I can keep track of how much clear each cutting step removes.  I've never cut through clear, but it's something that always worries me.

Looks awesome Cody.  Cut and buff makes are the difference between a mediocre paint job and a great paint job. My buddy and I went to the Autorama car show this past weekend and I was surprised at the number of cars that were not cut and buffed.  You could really tell the "home" paint jobs because of all the specks in the surface of the paint because they weren't cut and buffed.  In contrast, those that had been cut and buffed looked like yours, a mile deep.  :cheers:

blown motor

Would someone please explain exactly what Cut and Buff is to this novice? Thank you.
Who has more fun than people!
68 Charger R/T    74 Challenger Rallye 
12 Challenger RT Classic    15 Challenger SXT
79 Macho Power Wagon clone    17 Ram Rebel

soundcontrol

Nice, looking forward to that video! I wanna do everything on my car myself, so I guess I have to learn to prep and paint a car properly also. Have no skills yet, but lots of patience, how hard can it be...  :)
I did paint my Dodge Dart in the 80's, it came out nice for a garage paint.

Cuda Cody

I'll try not to write book response as I can talk about this process for days.   :yes:  Cut and Buff is done to flatten a paint job (the clear coat) and give you a show car look. It's the final step in a quality paint job.  The more clear coats you put on the car the more orange peel you will get, but the more you will be able to cut and the flatter the paint will look.  Most factory clear coats or cheap paint jobs can not withstand a lot of cutting as they are very thin.

I use the term "Cut" to describe the process of using an abrasive (sand paper) to "cut" the clear coat of the car.  It's the cutting is done wet (using it with soapy water) and removes the orange peel in clear coats and makes it appear super flat.  Cutting the clear coat removes a bit of the clear and can only be done a limited number of times before you will ruin the clear.  I start with 600 grit, then use 800, 1000, 1200, 1500, 2000 and finish with 2,500 or 3,000.  It's considered dangerous to start with 600 or even 800 if you do not know what you are doing or how much clear you have.  The cutting process of the clear is done just like block sanding before a paint job.  Blocks are used to keep it looking perfectly flat.

The "Buff" part is using a rotary buffer or DA polisher to buff the sanded areas to a shine.  3 steps of different pads are used with different rubbing and machine compounds.  This is were most people bust through the clear coat.  It's easy to make a mistake and burn the clear if you are not careful. 


Quote from: blown motor on March 06, 2017, 09:49:24 AM
Would someone please explain exactly what Cut and Buff is to this novice? Thank you.


blown motor

Thank you. I've seen cars where the finish looks really deep, like you could shave in it. That must be how you get that look.
Who has more fun than people!
68 Charger R/T    74 Challenger Rallye 
12 Challenger RT Classic    15 Challenger SXT
79 Macho Power Wagon clone    17 Ram Rebel

soundcontrol

How many coats of clear do you usually put on before the process, and does it need to sit a while before the "cut & buff"?

HP_Cuda


Unfortunately there are too many that do the cut & cut process.

:haha:
1970 Cuda Yellow 440 4 speed (Sold)
1970 Cuda clone 440 4 speed FJ5
1975 Dodge Power Wagon W200

Cuda Cody

I've done as few as 4 coats of quality clear (high solids) to as many as 7 or 8 high solid coats (over multiple days).  Anything more then 3 or 4 coats and I let it sit for a few days.  Then cut it open with 600 and re-clear the final 3 to 4 coats.  That gets you the best show car finish.  You can do good with 4 good coats of high solid clear, but you don't get the depth as you get with 7 to 8 coats.

The longer you wait to cut it the harder it gets to cut.  But the longer you wait the more it cures and the less pull back you get.  Pull back is what happens months and years later as the clear fully cures and shrinks.  The shrinking will give it a little orange peel and can show some of the body work sanding marks underneath.

Most body shops will cut within a couple days because it is easier to do, saves money on time and material and looks great when the customer picks it up.  But I wait weeks if not even months to cut it.  That way I get very little pull back and the paint looks great forever.  But it takes me weeks to cut and buff a car because it's so hard.



Quote from: soundcontrol on March 06, 2017, 02:59:28 PM
How many coats of clear do you usually put on before the process, and does it need to sit a while before the "cut & buff"?