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hondo402000
10-27-2009, 05:42 AM
I am getting ready to paint my 71 Triumph TR6, super red base coat and dupont scratch resistant clear, I purchased a PC kit with LC pads but dont know what products to purchase or the steps, I also have a 3m DA sander and will get the 3000 grit wet sand paper, once I wet sand the clear what steps and what products do I use, Way too much information out there for me to figure it out, I have buffed cars before but been a long time and things have changed

Hondo

Superdutytd
10-27-2009, 01:37 PM
I am getting ready to paint my 71 Triumph TR6, super red base coat and dupont scratch resistant clear, I purchased a PC kit with LC pads but dont know what products to purchase or the steps, I also have a 3m DA sander and will get the 3000 grit wet sand paper, once I wet sand the clear what steps and what products do I use, Way too much information out there for me to figure it out, I have buffed cars before but been a long time and things have changed

Hondo


I'm sorry but you are going to paint and wetsand a vehicle then remove all the damage from wetsanding with a PC? That is going to take a while by itself even though it can def be done. I would reccomend a M105/M205 combo starting with a yellow pad then working down to maybe a white pad with M105 then M205 with a white pad again.

sullysdetailing
10-27-2009, 01:44 PM
You are going to need a rotarty with wool and foam pads and products that are body shop safe like M105 and M205

Superdutytd
10-27-2009, 02:39 PM
A PC with an orange pad can and will take out 3000 grit sanding marks if thats all he is removing...

TurboToys
10-27-2009, 05:24 PM
well... if you really dont have anything but a pc... wetsand the clear by hand with the proper grits depending on your clear coat and how much orange peel you want to remove. then go and get a couple of trizact pads (3000 grit) for the DA sander. then after you go over the whole car enough with the DA with the trizact pads (use one and do the whole body in a certain order, then slap on the other use and go in the opposite order so you get an even removal). and then get some 4000 grit pads for the DA and go over it to remove the 3000... then you can move on to a yellow pad and 105 on the PC, which should get rid of the marks if you work it enough, like the post above mine said... work your way down, so after a yellow pad and 105, try an orange or white pad and 105, and then go to 205 white and gray.


but youll save a ton of time by using a rotary... time and headaches.

hondo402000
10-27-2009, 05:43 PM
I do have a rotary and some wool pads so it sounds like use it first and then the PC and foam pads. I hope I dont have to wet sand the whole car, thats not my intentions, but in case I have to I just wanted to know what to do. Only because I repainted my hood on my toyota 4 runner and got some OP in the clear so I wet sanded the clear and I did use my rotary on it but it still have some swirl marks, so when I get my PC and LC pads I can practice on the 4runner and getting it right then proceed on the Triumph once painted

thanks

TurboToys
10-27-2009, 06:21 PM
I do have a rotary and some wool pads so it sounds like use it first and then the PC and foam pads. I hope I dont have to wet sand the whole car, thats not my intentions, but in case I have to I just wanted to know what to do. Only because I repainted my hood on my toyota 4 runner and got some OP in the clear so I wet sanded the clear and I did use my rotary on it but it still have some swirl marks, so when I get my PC and LC pads I can practice on the 4runner and getting it right then proceed on the Triumph once painted

thanks


well you either wet sand it all. or none of it, if you try to nib out little pieces of dust that got into the clear, your gonna have tiny flat spots from where you did spot sanding... if your going to sand its best to do it all or nothing. depends on how happy ou are with how it looks when its done being sprayed.


forgot to add. if your going to wet sand AND/OR buff a fresh paint job. its best done within 72 hours of the paint job, and depending on the type of paint, you can start wet sanding and buffing (be careful with a rotary because of the heat and uncured paint), 10-12 hours after painting (depending on the clear used). best done early on because the paint is still uncured and extremely soft compared to fully cured, and is much much easier to work with.

hondo402000
10-28-2009, 07:00 AM
well I will see how it turns out, but I will have all the tools necessary if I have to. I plan on building a paint booth and spraying in a company whare house thats empty and is heated. I will also spray an old door very soon and practice and see what works, as soon as all my stuff come in, I ordered a PC and pad kit, some mernendez compounds and polishes in various grades, If I can paint a car I feel confident I can get it to shine like glass

thanks

Hondo

Mike Phillips
10-28-2009, 09:14 AM
The problem with trying to remove sanding marks with a PC style polisher is that if you push down too hard or if the face of the pad is anything but flat against the surface, (held on an edge), or if you're buffing on top of a raised point, the

Clutch-like-mechanism

Or the

Free Rotating Spindle Assemble

Will not allow the pad to rotate.

Here's the skinny on that, paint is removed best when the pad is rotating over the surface, not just vibrating or jiggling against it. When the pad stops rotating against the paint it more or less is left just vibrating or jiggling against it thus you won't be removing paint thus you won't be removing sanding marks.

Make sense?

Everyone out there hung-up on the word clutch happy? :laughing:


It's this free rotating spindle assemble that makes the PC style polishers safe because it dramatically reduces their ability to burn through the clear layer and expose the basecoat layer and it also reduces their ability to instill swirls although like you get with a true, direct drive rotary buffer.


That said, you can remove sanding marks using a DA style polisher as the write-up I'm working on documents that and shares how to do the procedure.

It will be pretty easy on flat panels but will be a lot more difficult on any body curves for the reasons I stated above.

So the right tool and the best tool for removing sanding marks out of an entire car that has been sanded is the rotary buffer with a wool cutting pad and an aggressive cutting compound.

Next would probably be the Flex 3401 but I would personally opt for a heavy duty RB like the Makit or the Dewalt models.

Cool car by the way, I've owned 6 vintage British Sports cars and once you get past the junky engines, transmissions and faulty wiring, the bodies sure look cool. For example, even the A.C. Cobra of Shelby fame started out as the A.C. Bristol, a British sports car.


:)

Mike Phillips
10-28-2009, 09:21 AM
well I will see how it turns out, but I will have all the tools necessary if I have to. I plan on building a paint booth and spraying in a company whare house thats empty and is heated. I will also spray an old door very soon and practice and see what works, as soon as all my stuff come in, I ordered a PC and pad kit, some mernendez compounds and polishes in various grades, If I can paint a car I feel confident I can get it to shine like glass

thanks

Hondo


Stick with the 4" CCS cutting pads and you can easily remove #2000 grit sanding marks as long as you get right on it and don't wait for a month to sand and buff.

How easy or difficult it will be to remove any depth or grit of sanding marks will in part be determined by how hard the paint is.

I've been using the Griot's Garage ROP for to remove sanding marks as it seems to have a little more power than the PC 7424XP but the XP model does in fact have a lot more power than the non-XP version and like the ROP can easily rotate a pad on the 6.0 speed setting.

The XP will easily rotate the 6.5 and 5.5 pads but again, these will rotate best on flat panels, anytime you have a curve the high point of the curve will result in more pressure to only portions of the face of the buffing pad and usually that's all it takes to slow down the rotating action of most PC style polishers.

And just to comment...

Using a rotary buffer to completely buff out an entire car as it relates to removing sanding marks is a ton of work so maybe hit the gym for month before you start the painting process.


:)

O.C.Detailing
10-28-2009, 05:36 PM
I think you all kind of missed the fact that he's using a scratch-resistant clearcoat. Unfortunately, I haven't really found a way to remove wet-sand marks from scratch resistant clear with a DA-type polisher AT ALL...it will remove lighter swirls, but not wet-sand marks. I'm not sure if being freshly painted makes it easier or not, but if you're lucky, it'll remove them if the clear is fresh.

Superdutytd
10-28-2009, 05:59 PM
I think you all kind of missed the fact that he's using a scratch-resistant clearcoat. Unfortunately, I haven't really found a way to remove wet-sand marks from scratch resistant clear with a DA-type polisher AT ALL...it will remove lighter swirls, but not wet-sand marks. I'm not sure if being freshly painted makes it easier or not, but if you're lucky, it'll remove them if the clear is fresh.

Oh good catch.

Mike Phillips
10-28-2009, 06:11 PM
I'm not sure if being freshly painted makes it easier or not, but if you're lucky, it'll remove them if the clear is fresh.


From my experience in the body shop world, I'm not sure if any of the major paint companies would ever introduce a paint that could not be sanded and buffed.

At the OEM level it's possible because it seems at the OEM level they never take into consideration that if a bird leaves a dropping on someone's hood and it leaves an etching in the paint, that quite possibly the owner might want to have a paint that's workable enough that they can remove the etching or pay a detailer to remove it for them.

All the OP has to do is check with the paint mixer at the PBE store where he's going to buy his paint and ask if the paint can be sanded and buffed and if so what are the limitations.

If the paint mixer says one of the cool features about the paint he plans on spraying is that it doesn't need to be sanded and in fact cannot be sanded, then it's time to find a different paint system because even if you were to never sand it after painting, whose to say it won't need correction work down the road?

Sometimes new technology isn't always better... (Vista cough cough cough)


:)

Mike Phillips
10-28-2009, 06:17 PM
M105 states right on the back label that it can be used on Scratch-Resistant Coatings so if they've done their homework on these paint systems in the aftermarket it's probably a safe bet that he won't have any problems.

http://www.autogeekonline.net/gallery/data/715/src.jpg

If it were me?

I'd probably stick with something less high-tech and let them dial these new paint systems i for a couple of years. The last thing you want is a paint system that's hard to polish unless you're going to park it in a museum.


:)

Superdutytd
10-28-2009, 06:36 PM
M105 states right on the back label that it can be used on Scratch-Resistant Coatings so if they've done their homework on these paint systems in the aftermarket it's probably a safe bet that he won't have any problems.

http://www.autogeekonline.net/gallery/data/715/src.jpg

If it were me?

I'd probably stick with something less high-tech and let them dial these new paint systems i for a couple of years. The last thing you want is a paint system that's hard to polish unless you're going to park it in a museum.


:)

Is this the same thing as a ceramic clear?