Results 1 to 11 of 11

Thread: Filling Mahogany Grain

  1. #1

    Filling Mahogany Grain

    Below is a picture of a mahogany entry door I’m finishing with spar varnish. It has 4 coats on it. I’m spraying the product, lightly tipping it with a brush and then putting another very light coat immediately after tipping. I’ve sanded with 220 between each coat but can’t seem to get the grain to fill. The varnish has been thinned about 15%.
    I finished an identical door a few months earlier the same way minus the tipping and had no problems filling the grain and getting a smooth surface.
    Any ideas are welcome.

    Last edited by Ken Krawford; 09-13-2021 at 2:42 PM.

  2. #2
    You just haven't put on enough. I am not sure I'd fill the grain with spar varnish, but...
    Grain filling with a top coat is a process of laying it on, sanding it back, and repeating.

    Have you level sanded?

  3. #3
    I’m not sure I’d call it level sanded. More like “light sanding”. I’ll sand more and keep adding coats.

  4. #4
    Join Date
    Nov 2020
    Location
    New Orleans, LA
    Posts
    42
    If you've got 4 coats you are probably ready for a good sand back. I usually do 220 or 180 if I'm just starting the process. I've recently gotten more comfortable with the process and will use a random orbital sander at the beginning of the sanding back stages. You are looking for the piece to be completely dull and feel like glass when you are done sanding back. This can take 2-5 rounds of applying/sanding back for me. One round is 3-4 coats of Arm-R-Seal. Any little shiny spot that you see after sanding is a pore/low spot. Once you get to the dull glass stage you can apply and and do the light scuff sanding between coats till you are happy with the build of the finish. Stearated sandpaper, a nice sanding block and a white 3m finishing pad to take away finish from the sand paper before it turns into corns works well for me. The sandnet sanding discs also work well since it is easy to suck/blow the dry finish out of them. I will use some foam material as a backer towards the end of the process to get into any slight contours I probably should have focused on more when I was sanding bare wood. Its a long, messy, pain in the ass process but I find it makes a beautiful finish with a nice depth/glow.
    Last edited by Cassius Nielsen; 09-13-2021 at 6:12 PM.

  5. #5
    Thanks for the feedback Cassius. I have this phobia with sanding clear finishes - I'm taking one step forward and 3 steps back or else I'll inadvertently sand through the stain layer ! I've added another coat since posting and it's slightly better. I'll follow your guidelines and press onward.

  6. #6
    Join Date
    Nov 2020
    Location
    New Orleans, LA
    Posts
    42
    It is a daunting at first, specially annoying when you did a particularly good job apply the last layer of finish and you gotta sand it off. One thing I look for is when the sanding dust starts changing color I know I have hit the wood or shellac I put below the poly. The shellac goes through this process if I use it which greatly speeds up the grain filling compared to poly alone. I have not used stain when doing this process. You can play it conservative, stop sanding early and do more coats of poly, I did the first couple of times I did this method. You will start to get a feel of how close you are getting based on how many little shiny spots you have left after sanding back a few times.

  7. #7
    Thanks again for your help Cassius. I just checked the results of my 6th coat and I think one more sanding and coat should finally fill all the voids.

  8. #8
    Join Date
    Jan 2007
    Location
    Michiana
    Posts
    3,040
    Did you blow out all the pores prior to finishing? A shop vac with a brush on the end can work well too.
    Sharp solves all manner of problems.

  9. #9
    I sanded with my ROS connected to a shop vac and then wiped down with mineral spirits.

  10. #10
    Maybe for the next door this product may help, https://www.jamestowndistributors.co...uct-detail/134

    I personally have never used the product, but for those who are looking for glass smooth exterior finishes it sounds interesting.

  11. #11
    Interesting product. This is the second pair of mahogany doors I have done in the last six months and I hope the last for a while. With the benefit of hindsight I should have sanded the doors before staining. I didn't sand the first set and the grain filled without much of a problem. Go figure !

    Quote Originally Posted by Robert LaPlaca View Post
    Maybe for the next door this product may help, https://www.jamestowndistributors.co...uct-detail/134

    I personally have never used the product, but for those who are looking for glass smooth exterior finishes it sounds interesting.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •