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cwestra
09-22-2008, 05:43 PM
How critical is it that paint (or primer) be applied soon after sanding primer? I have heard that you should scuff up a primed surface if it has been over 24 hours after either spraying or sanding. Is this true? It doesn't make sense to me. What changes (mainly after sanding) that would require re-sanding?

Brad-Man
09-22-2008, 06:31 PM
If you are using producys from the same manufacturer, follow their instructions as far as how long to wait for the next application.


Generally if you are talking about a sandable primer, it doesn't matter how long after you apply or sand it to coat it with either a sealer or paint - there is no chemical bonding going on - only mechanical.

Len
09-22-2008, 07:04 PM
How critical is it that paint (or primer) be applied soon after sanding primer? I have heard that you should scuff up a primed surface if it has been over 24 hours after either spraying or sanding. Is this true? It doesn't make sense to me. What changes (mainly after sanding) that would require re-sanding?

In most cases (depending on the type of material you're using) the paint will be a mechanical bond with the sanded primer so it doesn't make any difference how long you wait between sanding and painting. However the surface tends to get dusty and contaminated when it sits for a long period of time so it's usually best to sand and mask then clean the surface within a short period of time before painting.