Polishing with the PC

[junkie 0]

What exactly are you polishing.

 

If i was going to do this to remove swirls for example, are the swirls in the laquer or the paint? So when you guys do this does the laquer get removed?

[herisites 0]

Hi mate,

 

Get ready for some really geeky stuff!

 

The swirls you see are very thin scratches in the paint/lacquer caused by bad washing techniques ie using a sponge (grit on the paint, sponge has a large flat surface and you push the dirt around!). Basically when the sun shines down on the car its reflected off the hard edge of the scratch and back up in to your eyes so you see the scratch rather than the depth of the paint.

 

If your car has lacquer (corrado's do) then the swirls are in the lacquer. When you machine polish you use an abrasive polish which with the speed and heat build up from the machine cut the lacquer until the swirls are gone. You aren't cutting that much off really but its obviously not good to keep doing it or to do it wrong because if used incorrectly a machine polisher CAN burn through the paint (but tbh you will have to be pretty bad with it!)

 

There are polishes which 'fill' swirls though if you dont want to machine polish it. Autoglym Super Resin Polish is great at filling swirls. Basically the resins in the polish are pushed down into the scratch giving it a flat surface again and therefore not reflecting the sun up to your face, but it doesnt last very long unless you lock the polish in with a sealant, more specifically Autoglym Extra Gloss Protection. This is still temporary though so if you want swirls gone then you need to machine polish it.

 

Couple of diagrams for you (Shamelessly stolen from detailing world):

 

This is an exploded example of the paint.

 

This is how a swirl would look magnified.

 

This is how filling swirls work with a resin polish.

 

And this is cutting the lacquer to remove the swirls.

 

Are you thinking of doing it yourself?

 

Rob.

[g60greeny 0]

glad i didnt post my reply :lol:

 

i'm thinkin of gettin one for xmas,is it easy to pick up the skills :D

[herisites 0]

glad i didnt post my reply :lol:

 

i'm thinkin of gettin one for xmas,is it easy to pick up the skills :D

 

Yeah its not hard mate, the Porter Cable is the easiest which is why they are so common, they are random orbital polishers (like a floor polisher) rather than rotary (like an angle grinder). Not only are they easier but also safer because they dont generate as much heat as quickly as a rotary does, but in turn that makes the job longer as the polish works quicker as it gets hot which is why pros use rotary polishers and when done properly can do the job much quicker. There are guides all over the for porter cable, including video tutorials on youtube! Where as there aren't for rotaries so much because they can do the damage!

 

My advice (as well as anyone else who machine polishes) is to go down the scrappy and get a scrap panel to practise on. Dont just practise swirl removal but practise fcuking the paint up (if you can) as well so you know the limitations, but bear in mind that all paints are different ie german paint is bloody solid and takes a more aggresive polish or a harder polishing pad to remove swirls where as japanese paint (mainly honda and lexus) is like butter so you have to use a fine polish and at slower speeds etc else you can risk removing too much. So it might be worth getting a few panels, 1 from a vw/audi/bmw, 1 from a japanese car and so on.

 

I use a rotary polisher mainly because i couldnt afford a porter cable at the time and i got a rotary cheap off ebay, it was risky starting with a rotary but i practised and read about it a lot and soon got the hang of it. Nathan uses a rotary as well.

 

Also worth mentioning that you may want to hold on before buying a porter cable as there is a new version coming out in this country called the Ultimate Detailing Machine which is basically the same thing but improved plus it will come in 240v with english plugs etc so no need for a transformer like you need with a pc.

[junkie 0]

Thats why i ask the question herisites, i am thinking of having a good crack myself over the winter, been reading up quite a bit on the techniques and all. I just dont want to spend on the PC and then not do it right and i def want them gone not filled in.

 

I dont expect miracles as in it will look like its just come from the paintshop as its past that now just more rather working and improving what i have got until i can afford the new paint.

 

Is it not adviseable to do some wet and drying to flat the stonechips kind of thing?

[g60greeny 0]

yeah been lookin into "the Ultimate Detailing Machine" dont think they've released teh uk version yet though,seen um go on ebay we the transformer for about 200 notes!!!

[herisites 0]

Thats why i ask the question herisites, i am thinking of having a good crack myself over the winter, been reading up quite a bit on the techniques and all. I just dont want to spend on the PC and then not do it right and i def want them gone not filled in.

 

I dont expect miracles as in it will look like its just come from the paintshop as its past that now just more rather working and improving what i have got until i can afford the new paint.

 

Is it not adviseable to do some wet and drying to flat the stonechips kind of thing?

 

Well you might as well give it a go yourself then mate, its more fun doing it yourself not to mention more rewarding! You could quite easily get someone else to give your car a machine polish and getting it looking great and spend about the same (less in my case and if you take ardandy up on his forum deal!) as getting a porter cable and doing it yourself. But if you get it yourself then when you finally get the car painted and you have practised more, maybe done a few other cars then you can do your new paint because bodyshops machine polish the new paint but far too quickly leaving holograms all over it and they will also wash it before they give it to you so it will already have swirls etc! So its up to you.

 

Wet sanding isn't necessary in any case, you can machine polish over stone chips and scratches and in some cases they will appear reduced by rounding the edge of the scratch/chip off. Wet sanding is only really for the experienced to get rid of deeper scratches and blemishes as well as orange peel in the paint, this is because it removes more lacquer than polishing would. But you still have to machine polish out the sanding scratches and for this you ideally need a rotary polisher and an agressive polish. I have seen a video showing wet sanding followed by polishing with a porter cable and it didnt get them out enough and the area that was wet sanded was hazy, thats because the porter cable doesnt build up enough heat to cut that far down.

[herisites 0]

yeah been lookin into "the Ultimate Detailing Machine" dont think they've released teh uk version yet though,seen um go on ebay we the transformer for about 200 notes!!!

 

I would wait for the UDM mate as they will be coming out soon (rumors are late october) and they will be £100 with backing plates etc and they are 240v.

[junkie 0]

Actually mate your right, i never thought practice with poop paint then when its all new i will be on top form ready.

 

Never heard of holograms either in the paint, what kind of weird pictures can you get :lol:

[herisites 0]

Actually mate your right, i never thought practice with poop paint then when its all new i will be on top form ready.

 

Never heard of holograms either in the paint, what kind of weird pictures can you get :lol:

 

Exactly mate, definately worth it imo, like i said new paint doesnt necessarily mean great looking paint, it just means no stone chips! Thats why i get annoyed sometimes at show and shine events because some people with original 10+ year old paint put a lot of time and effort in to caring for their paint but the guy who's just forked out £5k on a paint job wins but if you were to compare them in the sun i bet the show car with brand new paint is more swirly than the 10+ year old paint thats been machine polished.

 

Next time you are out in bright sunlight walk around your car and i bet you will notice ghostly lines appear and disappear in the paint, those are holograms or 'buffer trails' and they are caused from bad machine polishing (usually at bodyshops or by dealers when new) by going too fast to get the car out the door asap and get the money so the polish used isnt broken down properly and is therefore only half way through doing its jobs so these lines are left behind.

 

Here is an example of holograms in my mates bonnet (before i polished it):

 

 

And after polishing (NOTE: i didnt go for a full de-swirl on his paint which is why there are still some swirls):

 

[junkie 0]

1 of the reasons i asked my original question was down to the fact ppl use paint depth gauges, how is this handy if your PC'ing the laquer and not the paint.

[A-J 0]

If you take some the laquer off you will end up with a small dull patch which doesn't look too good at all. The guys that use depth gauges (appro £500 IIRC) are generally PCing other peoples cars and don't want to make a balls up. Most problems occur when a car has previously been resprayed or has had a lot of machine polishing before. Some manufacturer don't put a lot of paint on at the factory either but VW are fine.

[herisites 0]

Yeah echoing what AJ said really, guys who machine polish other people cars have paint depth gauges so they know how much paint they have to play with. The fancy expensive ones tell you how thick the lacquer is and then how thick the paint is (its the lacquer you need to know though!) where as cheap ones just tell you how thick it all is down to the metal. VW and Audi's etc have lots of lacquer and its very hard too so if you are just polishing your corrado then you could polish it loads of times without worrying mate as you are hardly taking any paint off just to remove swirls.

[junkie 0]

Cheers for the info guys, just need to get my act together and make a start on it all.

 

Feel its going to be a long road.

[herisites 0]

Cheers for the info guys, just need to get my act together and make a start on it all.

 

Feel its going to be a long road.

 

Well if you need any help/advice mate just PM me and i will be happy to help out :)

[junkie 0]

My address is on its way and im free next wknd :lol:

[A-J 0]

Cheers for the info guys, just need to get my act together and make a start on it all.

 

Feel its going to be a long road.

 

It's really easy once you start, nothing to worry about at all. There are also plenty of guides on detailing world including some videos I think. It's also worth keeping an eye open for any of the open days that might be running near you where there will be demonstrations and you can ask questions or even have a go! With VW paint it's probably more difficult to make a mess than do a good job.

[VAG-hag 0]

Some good info there. Ive just been looking at these PCs on Cleanyourcar.co.uk & wondered who on here had experience.

 

Cheers 8)