Dining room table finish, knot filler???

[Lyle W. Kerr]

I am looking for some help on the eventual finishing of the dining room table I have been building. Ok, the table has been on hold for months, almost a year now. Back into it to finish for Thanksgiving this year, the problem I have with the top and finish is how to fill the knots. The table is being made out of 8/4 white oak for the top and spalted maple for the legs.

There are a couple very nice knots in the wood and other artifacts from the tree I want to keep. The issue, as you will see in the pictures, is the knots are pretty good size knots, almost all of the way through. I have been told to epoxy them and then finish in poly but I have not been able to get very good answers on what to use.

The plan will be to clear oil base poly the table for the finish. I just don't know what to use to fill the holes and what will be compatible with the poly.

Any help would be great.

[Neal Clayton]

I am looking for some help on the eventual finishing of the dining room table I have been building. Ok, the table has been on hold for months, almost a year now. Back into it to finish for Thanksgiving this year, the problem I have with the top and finish is how to fill the knots. The table is being made out of 8/4 white oak for the top and spalted maple for the legs.

There are a couple very nice knots in the wood and other artifacts from the tree I want to keep. The issue, as you will see in the pictures, is the knots are pretty good size knots, almost all of the way through. I have been told to epoxy them and then finish in poly but I have not been able to get very good answers on what to use.

The plan will be to clear oil base poly the table for the finish. I just don't know what to use to fill the holes and what will be compatible with the poly.

Any help would be great.

a) skip the poly

b) how much filling are we talking about on the knots? off the top of my head, the best way to blend them in would be to melt shellac flakes into the knot holes, sand/scrape them flush, and then use the same color shellac on the rest as the initial coat. that should blend the holes quite well. then you can come back and put whatever top coat you prefer (but not poly).

poly is for particle board wal mart furniture, not real furniture.

if you prefer oil a phenolic varnish such as waterlox or behlen's would be much better.

[Lyle W. Kerr]

Polyurethane is bad? Did I just give away how much of a novice I am? Thanks for the reply, I will look up the shellac flakes tonight and the waterlox/behlen's.

One of the knots is pretty deep, almost all the way through the table and about 1" wide at it's widest. I will see if I can get better pictures of them tonight.

The plan for the table is to make it look old and worn not perfect and new. I do however want the wood gran and spalted maple to really show through. When I run some mineral spirits on it it looks awesome. This is also the biggest project I have taken on so I want to make sure I finish it right.

The picture is from the article in PWW I got the plans from.

[Prashun Patel]

I'd use an epoxy. I'm partial to the 2-part, slow set ones. They have a longer bottle life for me.

The System Three T-88 I used will dry to clearISH and amber. You can make it darker and give it a little body with some sawdust.

Polyurethane gets a bad rap here. I just saw a repeat of an New Yankee Workshop episode about a roll-top oak desk. He finished it with no more than 2-3 wipe on poly coats. FWW also just did a story about using gel poly to finish a dining room table (http://www.finewoodworking.com/FWNPDF/011214040.pdf). Sam Maloof's finish mix includes 30% polyurethane.

I'm no expert - and I happen to be partial to Waterlox for just about anything - but I have concluded that Polyurethane is a fine choice for in-the-wood type / hand-rubbed-looking finishes - even on a table. The pic in PWW you posted looks like it's one of these.

So, I say that if you like the look of the poly in this application, you should be fine. (Check out the article I mention in FWW. It's from last month).

[Neal Clayton]

Polyurethane is bad? Did I just give away how much of a novice I am? Thanks for the reply, I will look up the shellac flakes tonight and the waterlox/behlen's.

One of the knots is pretty deep, almost all the way through the table and about 1" wide at it's widest. I will see if I can get better pictures of them tonight.

The plan for the table is to make it look old and worn not perfect and new. I do however want the wood gran and spalted maple to really show through. When I run some mineral spirits on it it looks awesome. This is also the biggest project I have taken on so I want to make sure I finish it right.

The picture is from the article in PWW I got the plans from.

that's why poly is bad. it looks like plastic. old/worn/antique is a look lots of people want, and you won't get it with poly.

melting shellac into holes will fill the hole in question, regardless of the depth, shellac in un-dissolved form is quite hard and rigid. there is a bit of technique to it, i would practice a bit before going to work on the table itself if you decide to try that route. you can buy shellac in stick form specifically for that purpose, actually. you melt it into the hole with a soldering iron.

adding another coat of the same color as the first coat of your finish should blend them in flawlessly.

[Prashun Patel]

old/worn/antique is a look lots of people want, and you won't get it with poly.

Yes you can...especially if it's an oil/varnish blend.

[Jim Becker]

One alternative to just using epoxy to fill in knot holes is to mix coffee grounds into the epoxy (or use CA) to create a brown filler that is a nice approximation of the original knot color. Mask off around the actual hole with your oak to avoid getting filler in the large pores!! Once you sand it smooth and do your final sanding of the table top, do a nice coat of de-waxed shellac to provide a barrier coat if you must use something containing polyurethane (which doesn't even like to stick to itself without some effort) or a waterborne finish. You may not need the shellac barrier coat with an alkyd or phenolic resin varnish, however, and the oils in the varnish will add a little color to the oak. Examples are Pratt and Lambert #38 for the former and Waterlox for the latter.

[Scott Holmes]

I would use epoxy tinted with TransTint dye to a color to match the dark wood around the knot. TransTint Medium brown seems to fit most often.

[Ty Bowman]

My father and I are finishing a newly made dining table with the Behlens Rock hard. It is coming out great, the wood is white oak sassafras and walnut. The only thing is make sure you thin it first. I read on here somewhere that the first coat went on straight out of the can, which we did. It got the orange peel look, luckily it is the bottom of the table (our test area). The top will be thinned and 6 or 8 coats applied then finished to a satin look.

Good luck it is definitely worth the time.

Ty

[Jerome Hanby]

My father and I are finishing a newly made dining table with the Behlens Rock hard. It is coming out great, the wood is white oak sassafras and walnut. The only thing is make sure you thin it first. I read on here somewhere that the first coat went on straight out of the can, which we did. It got the orange peel look, luckily it is the bottom of the table (our test area). The top will be thinned and 6 or 8 coats applied then finished to a satin look.

Good luck it is definitely worth the time.

Ty

That's a great idea! I've got a table project on the horizon and was already thinking Behlen's for the finish. Experimenting on the bottom should have been obvious to me <duh>

[Pete McMahon]

One alternative to just using epoxy to fill in knot holes is to mix coffee grounds

Coffee grounds??

[Faust M. Ruggiero]

Jim is a wood turner and coffee grounds mixed with CA glue is a great trick to fill dark voids in burl. Personally, I question why you want to fill the knots. They are natural to the wood and will add character to the finished top. My choice would be spray lacquer but you may not be equipped to apply it. I will recommend you pick a finish with good tolerance to alcohol (that leaves out shellac), good water resistance and something that will get hard. Pure oil finishes are easy to apply, easy to renew but take forever to dry and harden. Waterlox original has an oil base (tung oil) but also has a hardener. It is easy to apply and can be re-coated without stripping. It will give you a soft look with a durable finish. Try it on some scrap. Meanwhile, your biggest problem will be moving that monster without killing yourself. Happy Turkey day.
fmr

[Jim Becker]

Faust, I haven't turned in quite some time, unfortunately. But I've also used the coffee grounds method on a number of flat projects, too, where a darker brown filler for voids was appropriate. As to why fill knots...if one is going for the natural look, then yes, leave them be. But not everyone prefers that particular look and some find "holes" in a table to be disconcerting... It's just personal preference.

BTW, Waterlox is a varnish. While it has tung oil in it's base ingredients along with phenolic resins, once it's been cooked....it's varnish.

[Pete McMahon]

Jim is a wood turner and coffee grounds mixed with CA glue is a great trick to fill dark voids in burl.

I'm not a wood turner so I guess I missed that one. Personally I'd reach for a dry pigment like VDB, walnut crystals or the like to do it.

I once had someone call me for info on how to clean an "antique". How's that for a generic question? When I finally got him to reveal his "secret formula" that needed cleaning it was an "old trick a dealer\ finisher once told him, motor oil and BLO" When I laughed he hung up on me. I swear to you it's a true story. How could I make that one up?

I'm always amazed at the little nuances, some interesting some foolish, that are out there.

[Prashun Patel]

There's nothing wrong with coffee grounds or wooddust mixed in with epoxy or ca. It's used as a colorant and filler where absolute strength is not critical. Some CA can be thin and can seep into the surrounding wood.

To clarify something Faust said:

A 'soft' looking finish to me is an in-the-wood finish which can be achieved with an oil/varnish or wiping varnish. This involves applying it, letting it sit for a few mins, then wiping it all off so yr left after several coats with an even sealing coat and zero build. When left in-the-wood, then I agree Waterlox is repairable and soft-looking - but so is any other varnish or o/v when applied this way. If brushed or wiped on, and allowed to build, it will build a hard, glassy surface like many other varnishes.