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Topic Review (Newest First)
10-20-2013 09:22 AM
carolinacustoms
Quote:
Originally Posted by deadbodyman View Post
Please tell me your not buffing the inside of that fender ....I hope thats not some new trend...actually the paint on the inside of that fender is better than a lot of the finished paint jobs I see...Often we do things as we were taught and I was taught to sand with 1200 and start buffing with the wool cutting pad and 3m's micro finishing compound...and I never thought much about it ,I was young and had the time but these days I'm looking for quicker faster and better so the last one I cut and buffed I started with 2000 and then 2500 ,,,It would have been a lot quicker too but what always happens is I start out only wanting to nib out the trash but end up sanding everything flat...I really like starting out with the 2000....another thing is the color when I 'm doing black it seems to take forever even with the 2000 and 2500 but the last one I did was red and it only took two hours (only a hood) compared to days with the black ones but dam that black sure looks pretty when all done ...my problem is in the shop it looks perfect but when I pull it outside ,in the sun I find I missed a lot of spots and have to start all over again....

DBM, I won't be buffing the inside of that fender. It had a few small dust nibs that I sanded and buffed a few spots, but this is a driver/show car, not strictly show, so it won't be getting completely buffed. Thanks for the kind words on the paint job, I try to make them look good inside and out. I have to give the credit to Sata and SPI. I did not get those results before using either of those.

Kelly
10-20-2013 07:15 AM
deadbodyman
Quote:
Originally Posted by carolinacustoms View Post
The biggest factor in what grit you need to use starting off is how well the clear lays down. I usually start with 1200-1500 and go to 2500. The SPI Universal will sand really easily and buffs out well. The Euro buffs well the first few weeks, then gets a little harder, but still buffs well. Both will lay slick with little orange peel if gun settings and technique are correct. If the clear lays slick with minimal orange peel, there's no need to start with coarse paper, you are just making more work for yourself.

This is the inside of a mustang fender, sprayed with SPI Euro 4:1:1, Sata RP 1.4 at 37 PSI trigger pulled, full fan, 3 rounds out on fluid. This panel has not been buffed yet, but there's no need to start with anything more coarse than 1500.

This is a spot repair from a few weeks ago. Again SPI Euro with the same settings as above. Cut with 1500, 2000, 2500, buffed with a yellow foam then a black foam using transtar tricut.


Kelly
Please tell me your not buffing the inside of that fender ....I hope thats not some new trend...actually the paint on the inside of that fender is better than a lot of the finished paint jobs I see...Often we do things as we were taught and I was taught to sand with 1200 and start buffing with the wool cutting pad and 3m's micro finishing compound...and I never thought much about it ,I was young and had the time but these days I'm looking for quicker faster and better so the last one I cut and buffed I started with 2000 and then 2500 ,,,It would have been a lot quicker too but what always happens is I start out only wanting to nib out the trash but end up sanding everything flat...I really like starting out with the 2000....another thing is the color when I 'm doing black it seems to take forever even with the 2000 and 2500 but the last one I did was red and it only took two hours (only a hood) compared to days with the black ones but dam that black sure looks pretty when all done ...my problem is in the shop it looks perfect but when I pull it outside ,in the sun I find I missed a lot of spots and have to start all over again....
10-18-2013 09:38 PM
69 widetrack Your right John and one key is, if you know before hand that your color sanding and polishing...put more coats of clear on...if you run into a problem while your clearing...and you know your going to have to color sand and polish...put more clear on.

Don't put on 2 coats, wake up in the morning and decide to color sand and polish...that's when your going to run into problems...if you do in fact put 2 coats of clear on...don't like it the next day for whatever reason and your needing to do more than spot polish...sand it down and...put more clear on it. Very often, I will put on 3 coats of clear, let it set up, sand the vehicle, (now I have an Orange Peel free base) and put on several more coats of clear...by doing this when I go to color sand and buff, I can start with 1,500 grit and as John said, finish with 2,500 or even finer...you can virtually hand polish with fine grits like that.

Ray
10-18-2013 08:26 PM
John long When I painted the hood on the '36 i could not figure out how I got so much OP. It looked like a topical map of the Smokey Mountains. It suddenly dawned on me I had not replaced the 1.8 fluid tip. At least I had lots of paint on it. Where I am going with this is I blocked it out with 800 grit with an aluminum block and it buffed out great. I can't imagine needing anything courser than 800 and normally would be very comfortable with 1000 working my way down to 2500 for a dark color.

John
10-18-2013 07:57 PM
69 widetrack
Quote:
Originally Posted by carolinacustoms View Post
The biggest factor in what grit you need to use starting off is how well the clear lays down. I usually start with 1200-1500 and go to 2500. The SPI Universal will sand really easily and buffs out well. The Euro buffs well the first few weeks, then gets a little harder, but still buffs well. Both will lay slick with little orange peel if gun settings and technique are correct. If the clear lays slick with minimal orange peel, there's no need to start with coarse paper, you are just making more work for yourself.

This is the inside of a mustang fender, sprayed with SPI Euro 4:1:1, Sata RP 1.4 at 37 PSI trigger pulled, full fan, 3 rounds out on fluid. This panel has not been buffed yet, but there's no need to start with anything more coarse than 1500.

This is a spot repair from a few weeks ago. Again SPI Euro with the same settings as above. Cut with 1500, 2000, 2500, buffed with a yellow foam then a black foam using transtar tricut.

Kelly
Correct Kelly, As long as the clear coat has been applied with minimal Orange Peel, starting off with finer grits creates less work the finer you go. I don't start cutting clear with anything coarser that 800 grit wet and always on a block. This would be in a case with more than usual Orange Peel. The purpose of stepping from one grit to the next is to remove the previous grit's foot print. So if you start with a coarser grit, the next grit needs to remove the sand scratches left by the coarser grit, and the next grit needs to remove the previous grits scratches until you have an extremely smooth and virtual sand scratch free finish for Polishing.

The finer the finish, the less work the polish needs to do in removing the last grits sand scratch.

There are many different ways to approach cutting and polishing, what matters is the end result...so whatever works...and to add to that, from some experience, whatever works faster.

Ray
10-18-2013 07:32 PM
carolinacustoms The biggest factor in what grit you need to use starting off is how well the clear lays down. I usually start with 1200-1500 and go to 2500. The SPI Universal will sand really easily and buffs out well. The Euro buffs well the first few weeks, then gets a little harder, but still buffs well. Both will lay slick with little orange peel if gun settings and technique are correct. If the clear lays slick with minimal orange peel, there's no need to start with coarse paper, you are just making more work for yourself.

This is the inside of a mustang fender, sprayed with SPI Euro 4:1:1, Sata RP 1.4 at 37 PSI trigger pulled, full fan, 3 rounds out on fluid. This panel has not been buffed yet, but there's no need to start with anything more coarse than 1500.

This is a spot repair from a few weeks ago. Again SPI Euro with the same settings as above. Cut with 1500, 2000, 2500, buffed with a yellow foam then a black foam using transtar tricut.


Kelly
10-18-2013 03:11 AM
Imperial Kustom Believe it or not, I start off with 400 grit and work up to 3000. On lighter cars I might start with 600. All on hard blocks til I get to 1500. Its scary and requires a good film build and lots o time, but makes for one flat n glassy finish in the end!
07-09-2012 10:10 AM
67Elcamino I layed two very, very bad coats of clear. I had runs and tons of orange peel. I wet sanded all the orange peel and runs with 600 then 800. Shot 3 more coats of SPI using the correct 30 minute flash time intervals. I would say I have 4- 4.5 good heavy coats of clear on the car. So far cutting with 800 or 1000 I havent cut through the clear in any areas..

I have one panel in which I didnt wait the 30 minutes flash on the first two coats and I have solvent trapped. Im going to go back to that panel carefully sand down to try to get the solvents out. I noticed that I almost rather slightcut cut to the base that to leave the solvent trapped in there because it looks worse

Thank you for the advise. I am using a Meguires mirror finish soft sanding pad around the corners and curves.
07-09-2012 07:14 AM
mr4speed El camino, You are probably as anal as I am about that cellulite finish, I HATE IT!! How many coats of the clear did you lay down? If you are going through with this I can give you a little more advice, but PLEASE be very careful as I am a bit cautious to steer you in this direction. First off if you are in a rush or hate wet sanding and buffing chances are you are not going to pull this off. You can get the high solids clear wave super flat. I have done this already with the SPI universal clear. But I do put down 5 coats to make sure I don't go through anywhere. First thing is always use a fresh piece of 1000 grit, change as often as possible. Next is very scary for some, I have found that if you put a lot of pressure on that hard block for that initial cut it does flatten out pretty quickly, because you are forcing that block against the paper to CUT flat. The down side to this is if there is dirt in between you had better believe it's going down to your base or primer for sure. As far as your curved areas or edges go that you can't really use the hard block, what does work is the very small 3M squeegee. But this must be used with a FRESH piece of 1000 grit. It WILL work in these though areas. I am not sure how much clear you laid down but be very careful if you have already sanded and buffed, and are resanding certain areas. I always finish with 1500, 2000, then 2500. I then use a wool pad with that new 3M 06085 compound and it cuts like butter. Everyone has their own preferance for compounds and pads but this does really work nice for me.
07-09-2012 12:04 AM
67Elcamino After a couple panels with a soft block I switched to a hard block and im
Noticing its knocking down the peel and the wave much better. Im being very very careful with corners and non-flat surfaces. 1000 grit with hard block is working wonders. Thank you all
07-08-2012 10:29 PM
mr4speed I would have to agree with a lot of statements on the need to start off with the course grit papers for a guy just starting off and trying to do a real nice job with there first projects. There is A LOT to learn about what grits to start with verses how the finished clear laid down etc,etc. Someone new to this can get into some real trouble fast starting off with the course grits. Now having said that and looking at the pics of the elcamino, I can tell this guy really wants this car to look the best he can possibly get it to look. I have met quite a few guys that are unbelievable fussy. 67 elcamino may just be "one of these guys". Urethane wave is a real problem to get rid of with a "soft block" and I really don"t care what grit you start with. Im with John L on this one for sure. You Must start off with with a hard block and at least 1000 grit paper, I think of it as "shaping" the clear with that initial cut with the hard block. After that a large 3M squeegee works fine for your 1500 and up. This always gets that super flat laquer like look that has a mile of depth. This is a very tediuos and super time consuming job to say the least, and you had better make real sure everything is operating room clean, because sanding with the hard block you DO NOT want a piece of junk getting between that. I would not recommend this type of sanding the clear to someone fairly new at this, although there are always the exceptions.
07-08-2012 06:27 PM
deadbodyman I'll agree with that and if thats your first one its amazing ,some guys are just naturals....and have the eye for it...You should be able to get top dollar for that...I think the hardest part of all will be selling it....
07-08-2012 06:03 PM
John long Looking at your pictures it looks to me like you are well on your way to having one pretty truck. Keep up the good work.

John L
07-08-2012 11:10 AM
67Elcamino
Quote:
Originally Posted by MARTINSR View Post
"Made a lot of sense" is right!

This thread should be made a sticky, this thread has provided some GREAT information from everyone, if there is one thing that pops up over and over and is one of those frightening steps for a newbe it's cutting and buffing that paper thin layer of gold! The information gotten from this thread is VERY valuable information indeed!

I am with you Mike on the "urethane wave" too much being applied too soon is generally the culprit if you ask me.

First let me say that I LOVE cutting and polishing a show quality paint job, one that I shot of course, cutting and polishing someone else's work is scary to me even after all these years. But doing that final touch on a car, after a million and a half hours of welding and bare metal and blocking and all the hard work you get to take your time and cut that micro thick film down to perfection and make it SHINE, I LOVE it!

And my real "color sanding" experience started nearly 35 years ago doing complete show quality lacquer paint jobs where they got fully color sanded after every five coats (for a total of 15 usually) and I am talking every single square inch, EVERY single spec of orange peel or texture, even in the jambs! Like I say, I LOVE this stuff!

Anyway, as Mike said there are many ways to do this and many will get the job done well. If you have five different guys there may be five different ways that will exist simply because of five different talents. We all have had different lessons that have taught us to go down a slightly different road to get to the same end result.

The one thing I have always done is try to apply a perfect layer of product (be it primer, paint or clear) in that I have the most consistent film thickness. Then when color sanding I sand it the same way, with the most consistent removal of film leaving the most consistent film in the end. Sounds pretty much common sense and that is what most of us do, but I can't emphasize enough how important it is to cut evenly.

The coarser the paper, the faster this can get out of control, so walk softly when using the 800. And remember when I started doing this we didn't even have the 800! We did it with 600 and when that "ultra fine" (the first paper finer than 600) came out it was a GOD SENT!

Ok, my method in a nut shell. I don't remove ALL the texture with the first paper (typically 1200, depending on what it needs, some times 1000 or even that 800 in areas). This is one of the mistakes I feel guys will make. They cut it perfectly flat and then move on to the next grit, in my opinion that is removing too much material, and unnecessarily I might add. If you are going to have to be sanding out sand scratches from the 800, removing material, why on earth would you need to cut the texture completely off with the 800? Why not cut it down to where you have learned the next step (being 1000) is going to cut the texture anyway when cutting down thru the 800 scratches?

So basically I cut the texture down to where the next grit is going to remove the previous grit and the remaining texture, this is at least for the first couple of steps 1000-1200 but maybe even going to the next, 1500. Then leaving zero texture for the 2000. With this method you are removing the minimum of that paper thin film of gold.

I make sure that the panel is PERFECTLY clean before each step. The bucket is PERFECTLY CLEAN. We are talking clean enough to drink out of, and I am not exaggerating, clean enough to drink out of. The paper is again, perfectly clean. If a piece ever falls on the ground it is NOT reused without a trip to the faucet or sink to wash and get a very close inspection. Any rag to wipe the surface is kept clean like I was using it to wash my face. If the rag were to drop on the floor it would NOT be reused no matter what, a replacement is gotten. We are talking operation room clean here, there is nothing like picking up some microscopic piece of trash under the 2000 grit paper requiring you to cut that layer of gold more! So keeping things clean is of the UPMOST importance.

And on products, I use Mequiars products Click here

I have not used any paper that even comes close to the "Unigrit" paper they sell, it blows away 3m by leaps and bounds. The "Power cleaner" compound is the best I have found. click here It doesn't take nearly as much as other brands which means you don't have your walls and the rest of the car covered in splatter. It is amazing stuff if you ask me.

But honestly, I have said for years if Mequiars starts making televisions or opens a restaurant I will be there, they are THAT good of a company.


Brian
Ive learned the hard way... cleanliness is an area I need to work on. I have dropped a rag or paper and for not taking the 20 seconds to replace it Ive spend 5 minutes to remove the scratch it created.
07-08-2012 11:05 AM
67Elcamino
Quote:
Originally Posted by tech69 View Post
cleanliness and being anal is super important in paint and cutting and rubbing. It's the difference between a few swirls and a lot. We hired this guy for about 3 months, 30 years exp, had a car on a cover of hot rod and even an article on the build, but dropped the ball big time. Bodyman/painter but was sloppy, which was the reason he was later fired. He hopped on a few cars with us but mainly did the low end spot jobs. Then one day a fully restored Camaro they had only painted and changed the color of the stripes previously, had come in for some spot repairs around the drip rails...First he put a DA pigtail on the driver's glass, scratched the windshield with his moulding tool, and may have also cracked the windshield in an area where he had trouble getting the moulding off(he denied it) the tiny spot repair he did that got poly primed needed to be primed twice. So he does a decent job spraying it but now it's time for buffing. This is where the excuses came... He just couldn't get the swirls out, burned through one area, and lost his job for how he reacted to it and his lack of attention. Too stubborn to listen. In a nutshell, we all would go back there to check his "progress" and without knowing too much of his techniques I have an opinion on what killed the job...NOT KEEPING THE CAR CLEAN and not being thorough.

He didn't have a surefire way to get rid of 1000 scratch marks, which tells us he used to work in a crappy resto shop but let's not forget the time buffing and even polishing before his left over 1000 scratches were pointed out. At this point he's buffing and rebuffing trying to fight swirls while we occasionally and quietly would go over to the car to eyeball the areas where we saw sand scratches, and this guys trying to go to polish while we're still seeing swirls AND sand scratches. So then the excuses come out about product, waiting to long to cut it open, etc-etc. The car full of wool, dry compound(even in the cowl vent), break thrus on a few corners, mega swirls, and a disgusted boss. It got repainted and completed by somebody else. The moral of the story, this guy had a few guys fooled about his ability and it was cutting and buffing (out of all things) that finally showed everybody he over sold him self in the interview process by embellishing his skill level. So I have that as a reminder as to why I wouldn't recommend a non professional to cut a clear open with 800. A non professional painter might leave a lot of orange peel and starting with 800 makes me cringe at the thought of how much will be left to protect the car when it's all said and done. I don't think I've had to deal with urethane wave. I think if the bodywork and prep is perfect than the car will look perfect, and with that said I wouldn't recommend a newb to cut urethane waves out cause most likely the car won't be perfect anyways. It's just adding a bunch of risk to the equation and not yielding a noticeable result for their skill level. Not knocking anyone who does this technique, just don't think it should be recommended without a warning about implications.
I agree. I originally though that I would get this car smooth like glass but Ive come to the conclusion that there is no way if Im doing this all myself and being that this is my first time at it. Its just hard for me because Im anal about these thinks and Ill be embarrassed to show someone that really knows his stuff my finished work. But I can only do so much.. for %95 of the population this paint job is going to look awesome... I used to stress so much about that 5% .
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