Differentiating between grit scratches

N

Nor'Easter

Is there a method to distinguishing whether not you have removed all of your previous grit scratches?

I started a bedside with 1000 and stepped up to 2000, I figured there would be a noticeable difference but it doesn't show itself like I thought.


Anyone using dry guide coat to make sure everything has been hit with the next grit?
 
The easiest way I have found when wet sanding is to sand in a very well lighted area, even use the stand type lights or a hand held light if needed, and to sand in a different direction with each grit change. For example, left to right with 1000, then up and down with 1500, then at an angle for 2000, then the opposite angle for 2500. If you go finer than 2500 it will likely be using a orbital sander and again will be a different pattern to distinguish. Use a squeege to dry the panel often when sanding, to check for adequate sanding to remove the orange peel, then to remove the scratches left by the previous grit. Maybe JimC or Shine can offer advice for the dry sanding methods they are using.

Kelly
 
I have just been using water, it does not work. Bigger question is how do you know when you left enough clear on the car when you keep finding these scratches.
 
1000 to 2000 is too big of a jump in my opinion.
Once you're above 1500 it gets tough to tell. What I do is sand at a 45 degree angle with one grit and in the opposite 45 degree angle with the next grit. You will get little X patterns were the the previous grit scratches remain. Once all the X patterns are gone and your sanding marks are all in the same direction you have removed the previous grit scratches.
If you spray the panel with 710 (solvent) Wax and Grease remove and then wipe it off you can see the scratches if you look before it evaporates.
 
I will always sand in an "X" pattern with coarser grits, but for one grit I will use steep 45-55° angles, and the next, shallow angles (almost straight front to back, only slanting about 10-15°). Once you get to really fine grits, the "X" pattern doesn't matter much and you can just follow the contours of the vehicle with fairly straight lines from front to back. If you are unsure of a particular area of scratch, sand it briefly counter to the visible scratch direction. If the scratches are not coarse, they will disappear almost instantly.

I will go from 1200 to 2000, but 1000 is a bit too rough for the jump as '68 says.
 
You must log in or register to reply here.
Back
Top