# Arm-R-Seal sanding in between coats



## TravisN (Jan 15, 2019)

OK all, I promise I'm almost done with this table which means my questions will slow down considerably.

I'm in the process of applying the topcoat and I'm using Arm-R-Seal wiping varnish. I am still tweaking my application technique and the layers I've put down so far have not been perfect. I know you lightly sand with a high grit in between coats. I don't know how much leveling I should be doing with this sanding vs. how much will be fixed by a later coat and/or rubbing out. I don't want to lock in flaws in lower layers, but I also don't want to sand too aggressively to try and fix lines/streaks that may be masked by a better layer on top.

In particular, I'm noticing some edges at the ends of my table. I'm not sure how this is happening-it looks like I'm coming under when I do the other face, but I'm careful not to do that. So it might be that I'm lifting my applicator too early when I get to the end? Not sure. In any event, what is the best way to fix this? Should I focus on getting better layers above, or try and sand it smooth first? I'm nervous about the sanding, especially because these are on the edges which are prone to over sanding anyway.


















I'll take a closer look in the morning but another possibility is my prep sanding resulted in a bit of an taper there. I noticed that on the other side. But assuming it's a finish line and not a taper, would you recommend trying to sand the line out or putting another layer on top?


----------



## wncguy (Jan 26, 2012)

I'd try wiping the area with denatured alcohol to get rid of the line. Then re-apply the Arm-R- Seal


----------



## HokieKen (Apr 14, 2015)

Get rid of flaws as soon as you see them. Arm R Seal is an oil-based urethane top coat. So each coat is laying on top of the last. Not like shellac or lacquer that melts into the previous coat. I would sand your flaws out now before you apply another coat. After I finish wiping a coat on, I go back with a blue paper towel or clean cotton rag and wipe over it with very light pressure to avoid any runs or heavy areas. Good luck!


----------



## RichT (Oct 14, 2016)

The problem with sanding imperfections like that is that while you do flatten the imperfection, you also are removing finish from the surrounding area. It's just the nature of sanding, and being that close to the edge makes it that much more risky.

I'd use a card scraper to level that ridge.


----------



## EarlS (Dec 21, 2011)

I use a ROS sander with 400 or higher grit to sand between coats of Arm-R-Seal. If there are high spots, I sand them down using 320 grit. As long as you don't sand down to the bare wood Arm-R-Seal is very forgiving.

The problem I've had with scraping is that the high spot will come off but there will still be an edge where the material was removed. Sanding feathers it out better.

I use either a tee shirt applicator or a foam brush to apply Arm-R-Seal. Either way, I pull the applicator past the edge to avoid lift marks. Wipe with the grain. I don't come back and wipe the end perpendicular to the grain to avoid the lines like in your pictures. I also wipe off the sides to remove any drips or runs that might occur.


----------



## RichT (Oct 14, 2016)

> The problem I ve had with scraping is that the high spot will come off but there will still be an edge where the material was removed. Sanding feathers it out better.
> 
> - EarlS


Not if you know what you're doing. But, you're probably right that it might not be the best option for someone without much experience with a scraper.

The problem with sanding finishes like Arm-R-Seal is that, as Kenny said, it goes on in layers. The final film is not an amalgamation. Sanding can cut through areas of one layer into the next, which will leave visible lines similar to a topo map. I'm not saying it can't be done successfully but, just like the card scraper, you have to know what you're doing.


----------



## rwe2156 (May 7, 2014)

Are you thinning or applying full strength?

GF recommends thinning up to 10%.


----------



## wncguy (Jan 26, 2012)

My post this morning - 
"I'd try wiping the area with denatured alcohol to get rid of the line. Then re-apply the Arm-R- Seal".

I have no idea where my brain was this morning. I use DNA for shellac issues not Arm-r Seal.

Mineral Spirit for ARS. 
Very nice that people decided not to call me out as an idiot.


----------



## SMP (Aug 29, 2018)

Its strange that its such a perfect line like that. Did you run a rag around the edge to catch drips after or something?


----------



## TravisN (Jan 15, 2019)

Thank you everyone for your responses! I've been busy at work and unable to respond until now. I'll try and address all your comments in turn.



> Get rid of flaws as soon as you see them. Arm R Seal is an oil-based urethane top coat. So each coat is laying on top of the last. Not like shellac or lacquer that melts into the previous coat. I would sand your flaws out now before you apply another coat. After I finish wiping a coat on, I go back with a blue paper towel or clean cotton rag and wipe over it with very light pressure to avoid any runs or heavy areas. Good luck!
> 
> - HokieKen


That's what I thought, I just seem to have a hard time sanding away imperfections without affecting other areas (e.g., dipping into the stain).



> The problem with sanding imperfections like that is that while you do flatten the imperfection, you also are removing finish from the surrounding area. It's just the nature of sanding, and being that close to the edge makes it that much more risky.
> 
> I'd use a card scraper to level that ridge.
> 
> - Rich


My concern exactly! I have one area where I was trying to get some shellac drops out (shellac went over the grain filler and under the first coat of ARS)-thankfully I don't have the topography lines but I do have a "lighter" section.


> I use a ROS sander with 400 or higher grit to sand between coats of Arm-R-Seal. If there are high spots, I sand them down using 320 grit. As long as you don t sand down to the bare wood Arm-R-Seal is very forgiving.
> 
> The problem I ve had with scraping is that the high spot will come off but there will still be an edge where the material was removed. Sanding feathers it out better.
> 
> ...


Good to hear that ARS is forgiving! I do have a card scraper but I'm still trying to adequately resharpen it and I'm not sure I would consider myself proficient in using it. I'm afraid I would scrape away a bigger section.



> The problem with sanding finishes like Arm-R-Seal is that, as Kenny said, it goes on in layers. The final film is not an amalgamation. Sanding can cut through areas of one layer into the next, which will leave visible lines similar to a topo map. I'm not saying it can't be done successfully but, just like the card scraper, you have to know what you're doing.
> 
> - Rich


Yes, I'm still trying to figure out how to appropriately sand between coats. I never know if I'm sanding too much or not enough. I watch tutorials and it seems like they create more white dust (sanded finish) than I do, but I seem to create problems for myself (sanding deeper than seems good just to get a streak or a line out).


> Are you thinning or applying full strength?
> 
> GF recommends thinning up to 10%.
> 
> - Robert


I'm applying it full strength. I think my coats have been too light and so I get some pressure streaks. I'm afraid if I thin it more my application will be more spotty.


> My post this morning -
> "I'd try wiping the area with denatured alcohol to get rid of the line. Then re-apply the Arm-R- Seal".
> 
> I have no idea where my brain was this morning. I use DNA for shellac issues not Arm-r Seal.
> ...


LOL, I just assumed DNA and MS were similar enough that DNA would work 


> Its strange that its such a perfect line like that. Did you run a rag around the edge to catch drips after or something?
> 
> - SMP


I was also struck by the straightness of the edge. I did run the applicator (stain pad) along the end grain in order to coat that edge (something I thought I would need to do). I did not think my applicator was also running on the face, but maybe that's where the line is coming from.


----------

