Choosing a Polish

myshirt

I see that you cannot use, (or it's not recommended maybe?) 3m fast cut compound by DA. Rotary only.

Why is this? Would the DA just not work it the way it needs to be worked? What's the problem?

Would it dust up too quick??... eat my paint before the DA works it in???.. or micromarr it unless it's by rotary? I don't get it...

Maybe I have it wrong... maybe I'm just an idiot...

The paint on my car is hard. I don't have a paint gauge, but I know I need to be prepared for maybe using a cutting pad with aggressive compound.

I like what I'm seeing on 3m, I'll get the light polish and the finishing polish.

To be honest, one of those on a cutting pad at worst and I'll be fine... but all the same, if I want to go deeper, am I heading into having to use a rotary?

Curran

myshirt wrote: »

I see that you cannot use, (or it's not recommended maybe?) 3m fast cut compound by DA. Rotary only.

Why is this? Would the DA just not work it the way it needs to be worked? What's the problem?

You have it right - you could use it, but its not recommended. The DA simply wont work the polish in the same effective way that a Rotary would. If 3M adviced people to use it on a DA, the results could be just average and they'd have people complaining about it being poor, so they recommend it for Rotary only.

myshirt wrote: »

but all the same, if I want to go deeper, am I heading into having to use a rotary?

You'll get the same results with a DA, it will just take you more time!

Given that you dont have a paint depth gauge and by the sounds of things you are looking for full correction, then its better than you have to do a few sets/passes to get the results you require. Some panels may only need 2 sets/passes, others may require 4/5. Its always best to remove as little as possible.

Also....100% correction is never really achievable...so dont go chasing it, or you may have no paint left to correct or very little to correct in future!

myshirt

Curran wrote: »

Also....100% correction is never really achievable...so dont go chasing it, or you may have no paint left to correct or very little to correct in future!

How much paint does a heavy compound take off at a time? Assume Hard paint, foam pad, as against say a wool pad or a wet sanding job.
How much would it take? Roughly of course.

And how much have we to work with in terms of microns?

On the figure of 100% correction... what % would you rate this job on detailing world http://www.detailingworld.co.uk/forum/showthread.php?t=307460

for me, if I got this level of finish, I'd be back to my ten year old self at Christmas... fantastic job... I know there are more upsetting cases out there, but all the same this is car that was clearly assaulted with a sponge numerous times. It's just great to see the love and care it got when it pulled up on this gentleman's drive.

Curran

Impossible to say what level of correction that person has achieved! But what I will say, is that if your paint work is any way reasonable, and you give it a light machine polish, you will get similar reflections - its just that up close, or in direct sunlight that you will see the deeper swirls. From 10ft away, it will look showroom.

How much does heavy compound take off...how long is a piece of string!! Depends on how long you work the polish for, at what speed, what polish, what pad, ambient conditions, etc, etc. For example, if you got a cutting compound with the most cut, a foam pad with the most cut, spin it at full speed, you'll remove the paint in a matter of seconds.

How much paint do you have to work with, in terms of microns...again, how long is a piece of string - do you know that the panel hasnt been machine polished, wet sanded, or painted before...if you've owned the car from new, then you might have all the answers. Every car varies...you could have approx 130 microns on most of the car and have a few spots with 100 microns. For example, the BMW 3 Series (E46 model) often has a low point near the passengers side windscreen washer...but if you were to take 4 readings elsewhere on the bonnet they could all be in or around 120, and the low area approx 1ft square, could easily be missed.

But to give you an idea - this is a very Interesting Read

To be honest, I dont think you need to go anywhere near the likes of full correction...Id suggest maybe a three stage correction.
Compound - not too heavy a compound on not too heavy a pad - this will give decent correction
Refine - soft pad with medium polish - this will remove the defects left by the compound stage
Jewel - soft pad, soft polish to give the gloss!

Id be VERY surprised if you weren't chuffed with your work after that...there's no need to get chasing all the defects if its not a show car....its a daily driver and will have to be washed once a week. You'd be better spending the time, giving it a decent job now, and spending a few hours giving it a jewel every few months!

myshirt

Curran wrote: »

But to give you an idea - this is a very Interesting Read

Woah... nice work... those guys though, they are at a level way above my head and confidence level... I will remain a jaw-dropped observer

The link I had above of the VW though... I think if any enthusiast go do that over the bank holiday weekend they'd be flying it.. it is at the right end of the balance between the heights you can go to, and accessibility... looks very, very well.

I notice he used Scholl S3, and also 3m extra fine plus... reads as though he alternated between this 'as one' in a two part polishing process... would S3 not be of a higher cutting ability.... what I am thinking for me is 3m polish and finish by DA... and have S3 in the wings if needed.

Will take on you guys advice in working upwards from the least abrasive combination to the most abrasive to see where I am getting. But again, it is hard clearcoat, I may end up using some S3

Curran

I work on a lot of BMW paint...which is very hard also. S3 is my favourite polish. It gives great correction but finishes nicely, in the sense that it doesn't leave much work in the way of having to refine it. Id srongly recommended it, provided you also pick up their pads...the blue one works very well with S3.
Scholl S40 is a nicely polish to work with too!