wet sanding question

Hi there, mer1122 and welcome aboard...

Wet sanding is just what the term implies: Sanding using sandpaper that is previously soaked in water...

Soaking the base tissue of the sandpaper mainly serves two purposes:

1. It makes the sandpaper conform more easily and tightly to the surface being sanded.
2. It prevents sandpaper from clogging, thus making it more effective, as well as providing longer life for the sandpaper itself, which in turn results in a less tedious sandind job and a much smoother final surface.

Just make sure that you soak the sandpaper at regular intervals during the job, wipe thoroughly when done, and you're all set.

Another thing. Keep your model wet. Run running water over it every so often to keep the sanding goo washed away. Clean the model completely after sanding.

The other big advantage of wet sanding is that it keeps the dust away, very important for resin. It helps to get a smoother surface as well.

Thanks for all the tips! One last thing, how long do i need to soak the sandpaper before wet sanding? Are there any hard and fast rules or is more like "soak til bendy"?

QUOTE: Originally posted by mer1122 ...how long do i need to soak the sandpaper before wet sanding? Are there any hard and fast rules or is more like "soak til bendy"?

Provided that you'll cut a piece of sandpaper to the desired size, you should soak it into the water the way you'd soak a tea bag. Then... 5,4,3,2,1 and that's it... Don't forget to repeat soaking every so often...

right on. thanks for all the help guys! keep your fingers crossed for me!

Hi everyone! Just thought I'd ad my two cents in. I'd like to ad that one should make sure that the sandpaper is clearly marked for wet/dry use. I tried using some sandpaper to do some wet sanding once only to have all the grit turn into goo and come off the backing. I bought some wet/dry sanding cloths in my local hobby shop and they work like a charm! MER1122 asked about technique. I put my plane under the kitchen faucet and turn on a light and warm trickle. The warm water helps to keep my hands warm. Happy modeling!

Eric

BINGO, echolmberg! That is the most important step! I'm glad I wasn't the only one to find that out when first starting oh so long ago!...I wasn't, was I?

ah, excellent tip on the wet/dry echolmberg...i'd figured not to use the stuff with the paper backing but i didnt think to make sure the sandpaper was marked wet/dry...one more thing, should i always wet sand? or is it only appropriate sometimes?

Hi Mer!
Maybe the others can back me up on this but all I can say is that it's sort of a "feel" as to when you should wet or dry sand. I'm trying to think back about how I do it and I'd have to say that I dry sand to smooth out the overly-rough spots and then I'll wet sand when I really want the seam to be as smooth as glass (especially for natural metal finishes). I bought what was labeled as a "polishing kit" which was nothing more than several sheets of "polishing cloths" ranging from 1800 grit all the way to 12000 grit! I stop short of calling it sandpaper because the backing really is cloth-like more so than paper. To go back to your inital question, I don't think there is a time when you SHOULD wet or dry sand. You'll find your own advantages and disadvantages to each and you'll come up with your own system. I'll use one technique on one plane and another on the next plane. I say it's whatever you're in the mood for! Ha-ha-ha! Enjoy!

Eric

Old auto bodyshop tip: Add a drop of dishwashing detergent
to the water. It helps lubricate the sanding process and keeps the paper grit "open" and clean. Rinse the surface you are sanding often and flush with lots of water.

Also when doing larger flat surfaces use a foam sanding pad-otherwise your fingers will create "trenches" in the finish and make it difficult to get a nice, even finish.

Rick