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View Full Version : Help with building a slab coffee/end table



Charles Webber
06-23-2015, 5:24 PM
Hello all,
I am a new member and have been searching the threads but haven't found some answers for questions I am looking for. My father and I decided to start doing some wood working together as a hobby for us to spend quality time together. My father is retired and worked in carpentry so he has experience building homes, but not furniture type wood working. We have a bunch of tools. Probably most we would need. So our first project is trying to make a coffee table and several end tables. We salvaged a huge maple tree that came down on his land. Several of our family members want slab end tables for their homes as a "sentimental" piece as we all loved this maple. We had it set up off the ground for a year and then cut some slabs. We didn't know better at the time and cross cut the slabs from 2-4 inches thick. Later we found out that cross cutting isn't ideal and can cause a lot of warping and cracking. The slabs have sat for a year and we are wanting to start a couple of the tables. We built a jig to use a router and leveled the slabs off. So here are a few questions:

1. Can I start with a belt sander and then move to an OSS or will the belt sander leave cut marks that you can't sand out? The reason I am asking is because I started sanding one slab and it seemed to have left some scratches from the belt sander that I cannot get out for the life of me. I used the OSS after and it is smooth, but still see some scratches. If I stain this, will it look terrible?

2. How do I know if the slabs are dry enough? If I started a table and the slab was not dry, after I stain and poly/lacker, what could happen?

3. The first couple of table are having hairpin legs (I know, not really workmanship but what my sisters want)? So there isn't much planning needed here, right? Anything I should consider when installing these legs?

4. I want to try a dark walnut stain but my father wants to poly it only so you can see the detail of the wood. Any thoughts to this or just personal preference?

5. Any good suggestion on the stain to use? Do you have to poly/lacker after if you use a certain stain? If so, would you poly or lacker?

6. Is there a guide out there to building one someone has put on? I haven't found one.

I know pretty simple questions but when doing for the first time, just not sure. When we start making our own base, I will definitely have more technical questions. Thank you for the advice as we would really like to avoid stupid mistakes and waste some of the slabs.

Ken Fitzgerald
06-23-2015, 6:31 PM
Hi Charles! Welcome to the Creek.

I believe your thread would get more exposure in the General Woodworking and power tool forum so I am going to move it there.

Phil Mueller
06-23-2015, 9:41 PM
Hi Charles, and welcome. I'm a relatively new woodworker, and am sure sure some more experienced folks will be along.
Could you post a picture of the slabs...that would be helpful.
When you say you cross cut into 2-4" slabs, do you mean you cut it into round slabs?

Charles Webber
06-23-2015, 10:01 PM
Thanks Ken! Nice to meet you.

Charles Webber
06-23-2015, 10:04 PM
Hi Phil, yes we cut them into round slabs. They are pretty big for round slabs. We thought we would start with this before moving to a coffee table type slab. But when talking to a man that does kiln drying we found out they do not kiln dry round cut slabs because they warp and crack too much. So we were letting them air dry on doing the waiting game. I will send a picture of one of the slabs tomorrow. Thanks for the reply!

Jerry Miner
06-23-2015, 10:48 PM
So your "slabs" are cross-cut slices of the tree--- round disks, like cookies?

And they have been air-drying for a year? And they are still intact, with no big cracks or splits?

If yes and yes and yes, then you have won the lottery! Disks like this almost never dry without cracking.

A moisture meter will tell you the moisture content. A year for a 2" disk might be enough---the rule of thumb is 1 year per inch of thickness, but end grain dries faster, and you have all end-grain.

It will be difficult to sand these with a hand-held belt sander and keep it all flat, so be careful. Sanding end-grain is difficult just in general. Run the sander in a couple different directions, to keep from creating ruts.

Jim Dwight
06-24-2015, 9:50 AM
I can and have finished projects with nothing but a belt sander. It doesn't leave scratches any more than other sander types when used correctly. It can dig in and leave little grooves if you aren't careful. If your problem is scratches, you may have moved up to finer grit too quickly. I normally start with 80 or 100 grit and move to 150 and then 220. For something really rough I might start with 60, then go 80, 100 (or 120), 150 (or 180) then 220. I rarely go above 220 but have. If you were to start with 80 and then go to 150, you would have to sand a really long time to get the scratches out.

It isn't really a function of the type of sander, it is just the grit. Belt sanders are a little harder to use but do good work.

Charles Webber
06-24-2015, 9:54 AM
Thanks Jerry. Yes, they are round disks like cookies. I am attaching pictures. Yes, there are some cracks on the outer edges. For future reference, is there a way to avoid this? I thought I read that you can rub some type of oil on the edges to help prevent this. Also, those cracks that are now there, do I fill with epoxy? If so, how do you keep the epoxy from just running out? Also for my knowledge, what would you sand them with if not a hand held sander? Thanks for all advice!

Phil Mueller
06-24-2015, 11:32 AM
For filling the crack, I would probably wrap a piece of scrap board with wax paper and clamp it to the bottom if the crack and run some tape up the side. Fill the crack, let it dry, remove the scrap and tape and sand smooth.
As far as preventing cracks in the future, you may have some luck with sealing the ends...Anchorseal is one product, others suggest latex paint, roofing tar, etc. I've used Anchorseal on smaller branch ends with success. Not sure how well it would work on large trunk rounds.

Kent A Bathurst
06-24-2015, 11:46 AM
So we were letting them air dry on doing the waiting game.

Questions:

1. Where are these slabs - #1? [city, state]
2. Where are these slabs - #2? [indoors, outdoors]

2" - 4" maple takes a good while to air dry.....1 year does not seem nearly long enough to me.....I have never used rounds........but I let some 2" White Oak dry outdoors for one year and indoors for 4 years, in Georgia, and it got down to an acceptable level of MC%. I measured mine with a moisture meter with 1" pins, so I was measuring in the center of the wood, not on the surface like a surface meter does.

My concern would be that you have a lot more drying, and a lot more splitting, in your future.......

Jerry Miner
06-24-2015, 12:51 PM
I don't see any pics yet. Cracks can be filled with epoxy--either clear or tinted (I use System Three, but there are others)----you can make a "dam" from scrap wood, plastic, masking tape, or whatever. A "release barrier" --like some polyethylene--will make it easier to remove the dam after the epoxy sets up.

If the crack is large and/or deep, you can add a filler to the epoxy (to reduce volume/cost of the epoxy needed)-- coffee grounds, saw dust, sand, glass beads, ....

Sealing the wood while it dries can reduce cracks (but probably not eliminate them)---but be careful about products like Anchorseal that contain wax---they can prevent any later finish from bonding to your project.

A cookie like this cracks because the wood at the perimeter shrinks more than the wood at the center--this sets up stress in the cookie.

Sanding: the easy way is to run it through a wide-belt sander (as is used in a commercial cabinet shop)--or drum sander, but if you're doing this in a small shop, then, yes, use a hand-held belt sander. Just be careful, make even passes in two opposing directions, and work your way through the grits.

Bill Space
06-24-2015, 5:11 PM
I have made some of these types of tables in the past and have one in the living room now that was made probably 20 years ago and it's about 36 inches in diameter and 6 inches thick.

First thing I would say is don't get too hung up about the cracks. They tell you that the wood is real and not a hunk of plastic. Having grandkids the biggest issue I had with them was thinking if the kids spilled a glass of something on the table and it would run down through the cracks onto the carpet.

What I did, which worked really well, was push some aluminum foil down in the cracks a half inch or so, and then use dark brown silicone rubber caulking to fill the cracks. After it cured I took a razor knife and cut the surface even with the wood. As strange as it seems this worked really well and does not look bad at all. The table is Oak, I think maybe White Oak but not sure, and the cracks being dark brown contrast with it in a natural way.

Leveling the Slab with a router can be easy. What I did was make a bottomless box out of plywood that was larger than the slab, and position box so the top edge was at the level I want to get the slab to be cut down to. I made a kind of router sled from old bed frame angle iron. This was two pieces of that spaced about 8 inches apart. The router was placed in the middle. I used a square piece of metal to mount the router to.

I used a bowl bottom cleaning bit which has rounded edges to get the best results. I first used a bottom cleaning bit that had corners and that left lines. For the finishing cuts the router should be moved in circles following the growth rings more or less. When all done I do not recall having to do much sanding to get the surface ready for a coat(s) of polyurethane.

Hope this makes sense. Typing on my iPad leaves opportunity for lots of typos and creative editing by the software! I will try to post a picture later…

Charles Webber
06-24-2015, 9:53 PM
I am having trouble loading pictures. When I click "Insert Image", a box opens up saying to add image but it does not allow me to find the image from my computer. I will continue to try.
I am in upper Michigan (the U.P). The slabs are in a pole building stickered and stacked.

Bill, thanks for the input on routering. I used the cleaning bit that has the corners and it left a lot of lines that took a very long time to sand. I will try the bowl bottom and then the circular motion.

I have a few cracks on one part. Hopefully the picture to come if I can get it uploaded. I am planning on filling and then staining soon. The slabs are 44" x 38". The one I am doing now is a little smaller as I am using it as a practice piece.

The files keep saying the failed to upload. UGH!

Kent A Bathurst
06-24-2015, 11:28 PM
Failed to upload may mean too big - -size and/or pixels..........

Charles Webber
06-25-2015, 11:21 AM
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Thanks for the advice on resizing. The first picture is the practice slab. The second picture is a huge burrow we have. I put it on here for advice on what to do with it. My father wants to use it as a base for a slab end table. Just wanted to see if there are any other ideas out there. The third picture is the router jig we made to level the slabs. The last picture is showing the part that cracked.

I thought I answered this but do not see: We are in upper Michigan (U.P). The slabs are in a pole building stacked and stickered.

Another question: The epoxy do you get a paste or the tube that you can push it out? I would think the push out would be easier but I haven't seen that in black yet. Was thinking about doing the cracks in black.

Kent A Bathurst
06-25-2015, 11:57 AM
THose are cool.

We have some guys here that are more expert than I on drying lumber - maybe they will chime in - but in the UP climate, unheated storage, I gotta believe you are a couple years - at least - from dry to the point of "won't move much more".

I like the idea for a table base...........

Jim Andrew
06-25-2015, 2:37 PM
Cool pieces! What are you going to use for legs, or base?

Charles Webber
06-25-2015, 2:58 PM
The first couple we are just going to use hairpin legs. Those are for my sisters. Then we will start to get more creative for the base. I am sure I will look online to find something I like. Then the questions will come for how to do it right. :)

We have probably 30 slabs from the maple that fell. I wish I would have had some slabs cut long way, but I didn't know anyone that had a bandsaw big enough to do it. I would have loved to get a coffee table out of it. But there is another maple we have getting close to coming down that is even bigger then this one. So maybe by then I can find someone.

So would you use epoxy in order to bond the wood together and not crack further? It was suggested using brown caulk as well. Just trying to determine which to use. I am having a hard time finding black epoxy. I see stuff you can buy to mix with it. Was hoping to buy ready to use.