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I am about to start a new project and I need some advice / opinions. I will be making a coffee table that will house a small (12 drawer) library index card cabinet with a patchwork / calico top composed of multiple types of wood. The “pieces” will be approx. 4” wide , varying lengths.

I haven’t figured out the framing yet and if my history repeats, I will have to work at keeping it from being over-designed. Unfortunately I don’t have a capable BS so most things will be in straight lines. I also haven’t figured out the attachment of the top to the frame – I have done some research here but I’ll never turn down a good idea. I’m assuming the top will have to be able float a little which is of some concern since I expect the unit to be on the heavier side and will most likely be occasionally moved using the top.

I have several concerns / questions:

  1. I have the following wood available for use. Is there any I should leave out and if so, why? (Black walnut, Cherry, Ebony, Rosewood, Maple, Zebrawood, Canary wood, Paduk, Leopardwood, Purpleheart). The frame will be made from Ash.

  2. Is there one finishing approach that would be best to bring out the individual characters … Tung oil? BLO? Or should I be thinking about finishing each type of wood / piece pre-assembly to accommodate specific needs?

  3. My primary concern is in building the top … Is the 4” row narrow enough to be able to ignore expansion differences between species in the same “row”? If so, I can construct it rigid (glue, splines, dowels, etc.). Or should I be considering an unglued Tongue & Groove approach between rows? If a T&G approach is needed, does my PC890 or DW618 have enough power to run that type of router bit set.

  4. RE: Bread board end caps, how do you “hide” the rest of the table outgrowing the width of the cap? Is the cap left longer than the table is wide?
 

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Selection of wood: I'd look for a couple of things. Oil content of the material. I think you're asking for glue-up trouble by mixing in a really oily material

Look of the remaining pieces together. line them up together and move pieces around until you get a nice matching/contrasting set.

I'm a spline guy, strong, good alignment, relatively easy.Cut the grooves with the good side down so it's flat. Plane the wood to the same thickness to minimixe flattening, and of course joint the edges flat.

Generally tops are put on connected firmly to the front OR back edge, and the opposite edge is mounted through holes drilled oblong in the direction of expansion so there's a little room allowed for movement. Who knows how much it will actually be, but you can count on expansion rates varying with each specises. I don't like breadboard ends much, but if you do, you must allow for the expansion, so you don't glue them on, but cut another stopped spline on the end, connected at the center with a peg to hold it in place but loose enough so the rest of the top can expand freely. But if there's enough expansion, the end of the breadboard won't align with width of the top--which is why I don't much care for that look.

I'd finish the whole thing the same way, I thinking mixing finishes and stains is likely to look nasty. I'd go for a very transparent finish to bring out the wonderful variety of woods while still finishing after assembly. Use offcuts and scraps to try a couple of different finishes and see which one works best for you. Any 2.25 router should be sufficient for spline. If you don't want the spline to show on the end, stop the groove before the edge so you see only the main materials. Glue will hold the ends together.

Finish is a pretty subjective thing in terms of what you like, so only a little testing will give you a definitive answer.

Don't forget the spline grain should cross the main pieces' grain, so you will have to piece the spline material together for your top.
 

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Don't forget the spline grain should cross the main pieces' grain, so you will have to piece the spline material together for your top.
Tom,

Thanks for the insights. Since you brought it up, a quick question on splines. The problem I have with using splines is sourcing. I would need +/- 20' do do 5 rows of the table top. If I understand it correctly, the longest spline I can make will be the width of the material I'm using which would have to be sized to 1/4". Without a BS to resaw - that's a lot of planing / waste from 3/4" stock or even 1/2" stock.

I would consider using ply if I thought I could find decent quality - maybe some BB but I would assume a standard bit would not be sized properly for plywood stock. Am I missing something?
 

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I've found that hardboard (masonite) works well for splines. No worries about grain direction. Splines add little to the strength of the joint but, they're great for alignment.
Just be sure to start and stop the grooves short of the ends. You can shape the spline ends to conform to the bit's curve, if you want. I just cut the spline a bit short.
 
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Mark... sounds like a fun project using a hodgepodge of woods..very cool..

You will need to allow for movement...both for the top as a whole and for the individual components of the top.
For the top as a whole there are alot of acceptable methods. I'm very fond of these:

Figure Eight Connectors - Lee Valley Tools

Easy to install and if you use 2 to a side, should be enough to hold up when moving the table. But!!! if your table weighs a ton...not so much!!!

On a build such as this, I'd go about it one of two ways..
1: glue the individual pieces of the top to a sound substrate. MDF/Baltic Birch etc. 1/2" thick minimum. then trim the edges out with a hardwood and your breadboard.
Advantage here is that you can get away with much thinner pieces of wood.
Wood movement will be kept to a minimum
Considering the 12 drawers, this will be quite heavy when filled. I'd go with a 3/4" substrate..
2: SPLINE THE SNOT out of the top. Both directions.
Every joint represents the possibility for a possible structural failure.
The gran of the spline MUST be 90 degrees to the grain of the wood.
If the top is going to be more decorative than functional, splining the top should work just fine
If its going to be functional (support weight) then I'd definitely go with a substrate.

You can get away with resawing with the table saw. You may need to handsaw what the table saw dont get..but i'll work.
I'd lay out the pieces first..get em where ya want em..then glue em up in individual rows first. Glue up the pieces with the outer edges a little oversized. This way, when dry, you can cut to finished dimensions. Doing an offset from row to row may look pretty cool. This would also add to the strength of the joinery work.

Addressing your concerns:

1: Nuttin wrong here... great selection of woods..This will look fantastic when completed!!

2: Assemble the top as a whole first. No need to finish each piece individually first. Once assembled, apply a good filler first. Given the various wood pours your dealing with getting a 'dimple' free top would require ALOT of work. Multiple applications and sanding in between coats.
Oils inherently bring out the beauty in wood. Better than anything IMHO. But, they are not known for durability. (susceptible to scratching and the like) but easily fixed.
Go for depth and clarity rather than sheen or a mirror top finish. Let the wood speak for itself. Especially since you have such a great variety of woods. A high gloss or mirror finish is doable, but man, you're looking at a lot of work..I mean A LOT!! Play around a little with some of the scraps. various finishes. Let em soak in and let em dry, then scuff sand and wax before you make a decision. When it comes to finishes first impressions are often misleading.

3: Much of this addressed earlier. 4"s is fine, but you never want to just ignore expansion. Even with various species of wood. The effect is cumulative. 4" x #rows= ut oh!
Tongue and groove essentially is a built in spline. Gives ya good bit more glue surface. You'll have the spline in one direction, but alot of extra work to get a spline in the other.

4: Bread boards. There is no one size fits all. At some point it'll be a lil long or a lil short.. BUT.. keep in mind extreme movement occurs under extreme conditions. More often than not, you'll have nominal movement or practically none when project is assembled in a controlled environment and then put in an controlled environment. There are many ways to affix a breadboard end, including glue. I've used glue on several "smaller" under 24" tops without any issues, even years later. But on larger tops I go with a couple slots on the underside. Fine line between tightening down enough to maintain a snug fit to the table and allowing for movement.

On the top, save your energy and do the vast majority of your sanding once assembled. Are you building the drawers as well?

Just my 2 cents worth (actually more like a nickel :)) I'd love to see some pics as you progress thru this build.
 
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These are the clips I like to use Tabletop Mounting Clamps - Lee Valley Tools. They are really easy to put in. You just make a saw cut in the apron for the one end to sit in. They are set for the cut to be 3/8" down but I like to go 7/16" so that I put a little tension on the clips. A buddy likes to make his own out of wood but these are so cheap I can't be bothered.
 

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LOTS of good advice. One more thought: When you mix woods, consider putting in pairs of the same wood, starting with a single variety in the center, then working outward, a pair on one variety, then another variety on each side of that til the end.

Splines do not have to be long enough to fill the whole groove at once. You can piece them in, thus you can take moderately wide pieces of, say, maple or oak, set them upright and run them through the table saw. Make sure the blade is at 90 degrees.

Your splines will be about 31/32 nds, so you'll cut a couple of splines in the stock, then cut those splines off, then repeat. Thus you only need about 2 1/4 blade depth to cut your splines two at a time. If you use a narrow kerf blade, use a stiffener, which will reduce your available depth of cut, so I'd use a full kerf blade, even if it eats a little more of your stock each pass. We don't call it making sawdust for nothing.

You can also buy 8/4 thick stock so you can cut a large number of splines from a relatively short piece of 6-8 inch wide stock. The thickness of the stock can be adjusted to whatever bit you used to cut the grooves. Crossgrain splines glued in snug, are about as strong as the wood itself.

Hand Planing your stock flat on one side BEFORE you cut the grooves, face down please, will reduce your final flattening and make your grooves line up for assembly. You can hand plane the bottom flat after assembly. This is why the more seriously you take woodworking fine furniture, the more likely you will find a way to squeeze out the money for a planer!

I'd also love to see a few pictures of the top as you work on it, then another of it finished. At some point, I hope you'll post a picture of the finished cabinet... which should be a real beauty. Have you thought about making some mini panels with a similar wood pattern as the top, to go on the drawer fronts. That would turn this into a real treasure the kids will fight over in the will.
 

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Thanks everyone for all the great input. I'll post some details /pics on the construction and final result hopefully before this time next year. (I have an upcoming renovation that I expect to be somewhat disruptive to normal operations. If someone :smile: would like, I can take pictures of them putting insulation in my existing garage / workshop just so we can see how that's done. :wink:
 
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