Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: tigertiger on March 06, 2016, 11:21:23 am

Title: Gumming abrasive paper, or not.
Post by: tigertiger on March 06, 2016, 11:21:23 am
I saw on another thread a question about abrasive paper gumming up.


Wet sanding is an option. However, Stavros pointed out that primer paint is porous and wet sanding may not be a good idea.

For dry sanding, one option is to sand slower and with less pressure. This creates less heat, thus less clogging. Also don't be too quick moving up to the super fine grits.

With dry sanding, I have switched to silicon-carbide (white) open coated papers for any finish that is gummy or soft, it is made for furniture. One brand is Cristin. For me it has proved clog-less, even when sanding water based PU. I have also found it more effective on cedar and other sappy woods.
Caveat, because the grains are more open the smoothness of finish is about one grade below what you get from closed grain. In simple terms 150 open will give the same kind of finish as 120 closed. You will need to go one grade finer than you normally would for your final finishing sand. Another advantage of a white abrasive material, meaning no red staining.
There are several types of open grain papers, I think I have seen up to 3000 grit.

Sorry if I am trying to teach anyone to suck eggs here.


Any other tips from the experts?
Title: Re: Gumming abrasive paper, or not.
Post by: david48 on March 06, 2016, 02:41:11 pm
http://www.leevalley.com/en/Wood/page.aspx?p=20192&cat=1,42500
I know this is a USA site but it's a start . I bought one when I bought my Shopsmith these defiantly increase  abrasive paper/ sanding disk life . You could try Axminster Tools .
David
Title: Re: Gumming abrasive paper, or not.
Post by: dougal99 on March 06, 2016, 02:52:54 pm
Be very careful of your pronunciation if you order one over the phone  {-) {-) {-)
Title: Re: Gumming abrasive paper, or not.
Post by: Buccaneer on March 06, 2016, 06:14:35 pm
Axminster call them 'Abrasive Belt & Disc Cleaners'. Cost about £10 but my catalogue is 2 years old.

For hand sanding try Abranet. It is easy to unclog and does not produce so much dust. I get mine from www.restexpress.co.uk , but I buy in bulk for the woodcarving club. There are some good articles on line about it. Rest Express also do Discs, Belts, Strips etc. so it is available in a number of options. For normal hand sanding I reckon it lasts 3 or 4 times as long as some abrasive sheets.

John