Grain Filler
#7
Just recently finished some walnut end tables for my daughter.  Used 2 coats of shellac for wash coat, and then 3 coats of Crystalac semi gloss finish, which I have used before with good luck.  I have two questions that I would love some advice on:

As I applied subsequent coats of finish, I have build-up of finish right where I have edge glued the boards together, which got worse/bigger as I applied subsequent coats of finish.  I am pretty sure this is a rookie mistake, but if someone could tell me what is going on and how to prevent or fix it, I will surely take that advice into my next project.  

Secondly, despite what I would consider meticulous sanding with Festool and by hand, I still do not have as smooth a surface on the table top as I would have expected.  I am thinking I should be using grain filler before I put final finish coats on. Pros and cons of grain filler to obtain a smooth finish?  One last note - I have tried card scraper and hand plane and I am good but not great with them for a very smooth finish.  This would absolutely be my favorite way to get a glass smooth finish but I have some (a lot) of practicing to do yet.  As always, all advice is very much appreciated!
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#8
Where's JR1 when you need him??
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#9
I haven't seen anything from JR1 here in months. 

No amount of sanding will eliminate pores.  I personally like to see the open grain of walnut, but if you don't you would need to use a grain filler.  However, it's too late to do that now, but you can still get a smooth surface if you keep sanding your finished surface back after each coat has dried.  Use your ROS with 400 or 600 grit.  The finish will turn dull where the sandpaper cuts into it while the pores will remain as shiny depressions.  Sand back to remove as many of the pores as you can but don't cut through to your shellac and definitely not into bare wood.  Then apply another coat or two of finish and repeat the process until you end up with a uniformly dull sheen with no shiny pores.  Apply one or two more coats to finish.  Alternately, you could strip the finish off adn start over.  In that case, seal with your shellac coats and then fill the pores with a grain filler.  Seal that in and then apply your finish coats. 

I'm not sure what's going on with the glued edge joints.  Are your boards all of consistent grain orientation, plain sawn to plain sawn, for example, or do you have some plain sawn glued against quarter sawn stock?  If so, those boards will expand/contract differently with changes in RH and maybe that's doing it.  Another possible reason might be if you glued up your panel and then flattened it before the glue had completely dried.  In that case, the seams will contract later when glue dries and from troughs that will collect more finish than the rest of the surface.

John
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#10
I have 2 thoughts: if that "build up" at the joints is a ridge along the seam, you may be experiencing "glue creep", common with PVA glues. I've quit using them for table tops and use the plastic resin glues (the powder mixed with water stuff) if at all possible. Secondly, I've used that method John explained on oak quite a bit, and you can get a glass smooth surface doing that. While I use an ROS for the easly going, I do like to do the final 2 attempts by hand, wet sanding.
I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.
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#11
Fred, I think you might be right about the glue creep if the OP's getting ridges.  Same reason I've switched to PRG for tabletops and similar wide panels in solid wood. 

John
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#12
Thanks to all.  I have never heard of glue creep before, but that sounds exactly right.  Oh well, other than that, the tables look pretty good.  Will get some grain filler, and definitely some PRG - great tip - thank you!

I have not seen a JR1 post in months either.  Hope all ok.
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