Wet sanding

[Saul]

Anyone here that can throw some advise my way.

Basically I have a door panel to practise on before it get's taken to the local dump.

Want to use my da polisher rather than by hand.

Any tips or tricks? What paper to use, etc?

[Mo_miah]

why do you want to wet sand? what results are you after?

i have wet sanded a few cars now to remove deeper scratches the machine polishing alone could get rid of
wash and clay the area first to prevent contaminates being dragged around
i used 2000 grit paper, started by soaking the paper in warm water (warm water to stop my hands getting cold )
then only sand the area that needs work and avoid going over onto good areas too much
continuously spray water on the area as you work
dry with a MF towel to see the results
once left with an even haze i machine polished using megs 105 then megs 205 until shiny

used this method and a VW Golf that got scuffed by a van
and an Audi A6 that had some deep scratches

[Mo_miah]

might be worth creating various degrees of damage across the door and try repairing it

when i do repairs if the scratch is down to the metal i always use an abrasive pen to clean out the scratch even if you cant see rust there maybe a tiny spot forming
touch up with primer and leave to dry, primer absorbs moisture so once dry apply the colour
i mix the colour and lacquer and apply using a cheap super fine art brush
dont brush it on, dab small spots and build up before the paint fully dries
leave to dry for a week
then wet sand and polish to make it even with rest of the area

[Saul]

why do you want to wet sand? what results are you after?

No main reason, just thought I'll have a crack at it.

If anything just for a deeper shine. There are no major scratches etc on bodywork.

Have you got a paint depth gauge? If so did you use it ?

[Mo_miah]

no i dont use a paint gauge when repairing scratches, tbh if the scratch is that deep that i will end up wet sanding all the clear off then i will be repainting it anyway
i always use a mild abrasive and dont polish the whole car that often so a paint gauge is not needed
if i was to work on someone elses cars for a living and didnt know the history of the paintwork then i would use a gauge
most cars i have worked on have never been polished and will only ever receive a couple light polishes in the cars lifetime

start with a light polish like megs 205, check the results, if you need to cut heavier try megs 105 and keep going until you get a feel of the cutting power of each stage, then when you do work on cars you can look and know straight away which stage to start at

[Graeme1975]

I did it on a partners black Corsa that got keyed along the whole door. Was quite deep but I just cleaned out the scratch, filled in with cocktail stick building layers up then wet sanded with 2000 grit. Stood back crapped myself then did bit more sanding with 2500 grit then 3000 grit then machined out with mega ulrimate Polish. Came up a treat apart from one tiny bit I burnt through and if you looked very close you could just about make out the scratch. No risk for me back then as it was due to get painted but saved that in the end.

[Mo_miah]

Cocktail stick method works a treat too
Nice guide graeme thats basically what i do and so do a lot of repair places when the customer is on a budget