My son bought a new unfinished front door and stained it without sanding it and it looks awful!!! His stain job has streaks and it’s running all over the place. I know what you are thinking, who would do that – my son who has no experience in staining a door and couldn’t wait to get it done right. Does he need to take off the stain and start over or can he just sand it and stain it again.
If the door is unfinished (no clear coat) your son can sand through the stain to remove it. This depends on the stain and the type of wood. The stain must be removed before restaining and sanding can be a great alternative to using a stripper. Try this on a section of the door and see how it goes.
If straight sanding is to much work, use a strong paint stripper, wash the door and allow to dry then do some sanding to finish up the prep.
Not easy but doable.
First you will need to use a paint/varnish stripper that is safe for fiberglass. Chances are not every bit of stain will be removed from the wood grained areas. This is fine as you will need to use a gel stain to restain your door. The gel stain will add color and depth. Once it is applied and fully dry (24 hours) you will need to protect it with a clear coat.