Monday, 17 April 2017

I table a motion!

So just when you thought I wooden make any more puns...

...I decided to make a coffee table. Not just any old coffee table though, oh no... I'm opting for an awesome one! One SOOOO ludicrous, the actual chances of me completing it are about the same as... well something utterly ridiculous; like me being able to pull an even number of socks out of the washing machine... or stopping the microwave at the exact time that the handle of the mug I put in is actually facing me. You know, crazy stuff that just won't happen in my lifetime, that kinda thing.

Steampunk is cool. So I started off with a steampunk theme, and that of course means travel, navigation, astronomy, brass, wood, leather, glass, etc.

I had a look around and found a beautiful and inspirational image of a sextant, which I thought would suit this perfectly. It's all metal, but should look great in wood.

The top flips back on a hinge to reveal the inner workings. Now wouldn't that be great in wood?

Beautiful, eh? So I decided to take this as the inspiration; the table legs would be the screws, the top of the table should hinge back and reveal the inner area, etc. To start with I mocked it up in ZBrush and did a few quick renders with Keyshot.

It was looking promising and the idea seemed to be solid, it's just a matter of working out some of the design ideas a bit better... I wasn't happy with the top of it, so decided to have alook around to see what else I could do there rather than the original sextant idea. This had to be a working table, so having a piece protruding from the top wasn't going to work. I also wasn't thrilled with the inner piece... In keeping with the astronomical theme, I searched for an orrery and accidentally came across a thing called an astrolabe. It was a mechanical device used in antiquity and is an elaborate inclinometer, historically used by astronomers and navigators, to measure the inclined position in the sky of a celestial body, day or night. It can thus be used to identify stars or planets, to determine local latitude given local time and vice versa, to survey, or to triangulate (guess who just visited wikipedia *cough*).

So in searching for more info about this device, I came across the rather excellent website

Some generous souls there allow you to print out vector graphic versions of the astrolabe, specific to your region. Perfect! So I entered the values for Dublin, Ireland, and hey presto, a free astrolabe, supplied as a vector graphic, perfect for printing out and CNC'ing. Doesn't get much luckier than this, didn't fancy making this in Photoshop or Illustrator (mostly coz I can't use Illustrator).

The settings used for Dublin, Ireland

The scale of my original model also seemed to work until I actually printed the top part out to scale and spread it out on the ground. At almost a metre in diameter, it was FAR too wide. I scaled it down to 800mm instead and it seemed about right for a coffee table. Back to ZBrush to update the model.

So this was closer to the actual dimensions I would need. I opted for European oak as the wood of choice on the advice of the master craftsman Chaïm from Hillpicket Studio, here in Avoca, Co. Wicklow. It's here I am learning how to make this table.

Anyway, I've decided to distress this to make it look like the kind of thing you'd find on the back of the Black Pearl from Pirates of the Caribbean, so it will ultimately be more aged looking than it is here. Also, some of the grain goes the wrong way, etc, but this render is purely for scale and dimensions really so I'm just gonna keep it as is.

Looking at it though, it still needs work. The astrolabe has nowhere to sit and it's looking a bit boring.
It looks like this (see below) and is going to need to be seen in order to be used properly. It also has a moving part called a rete (pronounced ree-tee), shown below in thick black, and this should spin on the central axis and depending on the angle chosen, will point to various stars (the pointy bits). So yeah, this has now become an engineering challenge... (gulp!)

So anyway, back to ZBrush for more changes if this design is gonna make it on top.

Entire table with glass on top and I decided to add a small door for storage. The hand crank is intended to spin the rete.

The top temporarily hidden, to show the inner mechanics on a shelf inside.

Hidden top showing the crank and worm gear mechanism necessary to spin the rete.

Here I've hidden the main barrel and the top and even legs to show the proposed worm gear and crank to drive the rete.

So as you can see, I've clearly gone mad. This thing is gonna to take forever to build...

I'm also intending on burning in some designs on the side, either on the door itself or the other side with something like this, coz why not add pyrography to the mix, right? ...right...? *takes out credit card and orders a pyrography machine*

So, the design isn't actually finished yet, but it's at a stage where the woodworking of certain parts can certainly take place. In actual fact, I started on the hinge some time ago and it's still valid, so that just proves my point. Just sayin' is all....

Here's the progress so far.
The beginnings of an oak hinge

The secondings of an oak hinge

The gluing of an oak hinge

The finaling of an oak hinge

The backings of an oak hinge (see what I did there? All these "ings" just for that one - totally worth it)

The hinging of an oak hinge.... I mean, a working hinge! Complete with automatic stopper built in. Pleased with this.

I also cut out a quick small latch to go on the door also (quite frankly there are so many parts to this table, I just need to make progress wherever I can).
A latch for the door. I'm probably going to change the rete pointers to match this motif, although the pointers will probably end up brass.

I also turned some wooden screw heads which are going to be glued onto the hinge to simulate the real thing. Not thrilled with how these came out, they don't hold up great to close inspection, so may have to revisit these. Haven't glued them on just yet.
Some screwed up screws...

Okay, so the next stage was to make the base. The wood planks come 24mm thick, so although the original design was thicker than that, on Chaïm's advice I'm compromising in order to save on weight, hassle and time. I'm just gonna go with the 24mm and see what kind of router cutter will give me a nice profile.

The main base circle is divided up into 4 parts. The hole in the middle will accommodate a plywood base which should be lighter than the oak (this table is already going to get incredibly heavy). The important thing is that each of the 4 parts have the grain of the wood go along their length for maximum strength. To do this, two planks are glued together for each of these parts and then a template is made out of plywood in order to cut them all consistently the same size. As the base is 800mm in diameter and the hole is 600mm, I measured up the inner and outer diameters, drew the outline on a piece of plywood, and then traced this template on the planks, ensuring to keep the wood grain as long as possible. The pieces were then cut on the large bandsaw (thank you Chaïm) and then came the business of sanding them down. After some planing on the edges I realised I was never gonna get them to line up perfectly, so we went back to the sander and that did a great job of straightening them out. Next stage is to draw up some dowel marks, drill some holes for the dowels and then glue them into one piece.

4 pieces, grain running as long as possible, ready for dowel marking and gluing

An early look at hinge size on the base.
Dowels added to increase surface gluing area and prevent slippage
All glued and strapped together. You could call this a strapping piece of work... (you'd be awful if you did, but still, the option's there)

I'm also in the process of trying to figure out the top part of the table. I've been thinking about how to make it so the lid can lift and pass the central pillar which is driving the rete. So I've come up with this solution for now.

A centre piece "cog" should allow the top to hinge upwards without catching the rete. It will also allow the rete to grip the centre piece and rotate.

Just a round hole needed for the main table top (rete hidden for clarity). Clearance when pivoting the table open shouldn't be an issue.

Should be able to make this in 2 pieces and glue them together. Right now there's a good chance I'll have to get a metal gear worm (rather than make one from wood) and attach this new cog to that.

As ever - wildly ambitious!

Chaïm has advised I get some flexi plywood for the main barrel, which I've ordered today. The grain should be vertical in order to not split as it bends. As the main barrel is 400mm in diameter, and as C = πd, the circumference works out to be 1256mm, and these sheets come in 1220 x 2400. Just 36mm short of using the bottom half of a sheet rather than having to cut into the 2400 length. Had the circumference been 380mm wide, I could have saved a lot on plywood. Lesson learned. Ah well!

So the time came to make the barrel. The base of the barrel already existed and fit snugly into the base.

After that it was a case of making a support cage to wrap the barrel around. To do this we made small pieces of oak and drilled in dowels into them to fit them into place for the top ring and the base.

Cage supports, 15mm x 15mm

One top ring, ready for the top of the barrel.

Once that was done, it was time to glue them into place into both the top ring and bottom base, effectively making the cage. This was them being glued together. Obviously it's nearly impossible to get cramps that would fit this, so gravity did half the work, some books the other half.

Wrapping the flexi-ply around the cage. This was screwed into the supports to hold it in place. The idea at this stage was to wrap this with an oak veneer, but new ideas were forming already....

The final barrel. The gap at the top was down to me miscalculating the height. D'oh. Ah well, it's gonna be covered, so my secret shame will be hidden ultimately.

Right now, I have a barrel with hinge and a base with feet. Mocking up the design at home with these parts I realised that adding the legs from the original design was going to seriously impact the functionality of the table. It would be nearly impossible to get your feet under it and you'd probably knock your knees off it anytime you came near it. Time for a rethink.... I'm also still not happy with mechanics of it all - it feels overly complicated and a bit clunky. I've been looking into CNC'ing the astrolabe image into the top and that's not really that feasible. For one thing, getting a CNC large enough is difficult, and doing it in parts presents other problems when using such thin lines (what to do about 2mm lines where parts have to be glued together for example). Another solution is to use vinyl stencils and sandblast the wood, and that's worth considering. Thing is, is it steampunk enough?

So back to ZBrush and playing around with the design some more. I'm much happier with this new look. If I use sheet metal either etched or engraved, I can get much smoother and cleaner results than cutting into the wood as the surface is so much smoother. I can also age it, and the mix of materials looks good to me (I may have overcooked the black look here, but I'd like it to be an old metal if possible). For the barrel, rather than veneer it with oak, perhaps a leather covering would serve to make it more interesting, and if I add copper studded rings around (12 studs, one for each month of the year), it could be a nice accent. The door needs to be sacrificed if I'm doing this, but as I can now see how difficult it would be to reach into anyway, I'm okay with this. I'm not sure about the plain leather just yet, I may revisit this and do a different design, perhaps using pyrography or embossing something into it and then staining it a more interesting colour. I've also aged up the oak to help envision what it might look like when finished. And finally, the entire mechanics have been reworked. Rather than have the mechanics on the inside, if I make a hemisphere on the top, and attach it to the spinning rete, then I can spin the rete under the glass by simply spinning the hemisphere. Much simpler solution and much more elegant too. I've always admired wood grains and see them mimicking planetary gas patterns, so this is an excellent opportunity to place something like an embedded wooden planet into the design and still look nice and fulfill the functional requirements I need.

Simply rotating the dome will spin the rete. No more complicated and "never-gonna-be-finished" internal mechanics. Yay!

With the glass in place, and only the top of the spinning dome poking through the glass. The whole top can still be opened up thanks to the hinge, allowing access to the inner barrel.

The new simplified table top. Three metal discs, one for the outside ring, one for the inner ring and finally the main disc with a rebate in it to house the ball bearings the rete will spin on.

As I will be going with a black anodised aluminium base for the 3 discs, I have mocked up the artwork and added some clouds to it (coz hey, it's for Dublin!). Hopefully the laser etching process will come out nicely with this added.

The placement of the Dublin text should work nicely with the rotating rete once that's added on top. There'll be the names of the stars laser etched onto the rete also, I just haven't done it yet! Am thinking of going with plain aluminium for this part, as I like the grey. Alternatively maybe brass, but I need to see what would be strong enough to support itself when it's this wide. Right now, I have no idea!

More screenshots of the measurements, etc. 

As you can see, I didn't bother going back to correct the astrolabe texture with the Dublin text and clouds onto this. Too much hassle!

I've already ordered the ball bearings (in fact, I have them already!) and have now also ordered a vegetable tanned leather half hide (3mm thick) and some copper strips and copper tacks on ebay. I'll have to stain the leather, but that's fun and I might even emboss some detail on it... at least now I have the option!

P.s Leather is expensive! Especially this much... I need 40cm x 134cm in one large strip.

I added an interior to the barrel also, so when you open it up you won't be looking at the spines of the barrel.

I also added the feet to the base, you can see the dowels here, which aid with sticking, by increasing the surface area of the adhered area.

I've decided to add a fabric lining to the inside of the barrel of the table. This will have a cushion of sorts in the bottom which will have buttoned and battened fabric. So I've cut out a piece of chipboard to serve as the base for this. Am thinking of possibly going with a velvet for this.

I've also glued the wooden screws I turned onto the hinge now. This is pretty much ready to get added to the main table now, I just need to make some final decisions on the barrel and the base before committing to it.

And finally! A mockup of the final thing. I can now see what it looks like in the room and roughly how well it will serve as a table. Obviously the rete and top are just temp placeholders, but I can get a sense of where I'm going with it now. In the backdrop you can see the aluminium sheet all wrapped in cardboard to protect it. I got the sheet from Hisun technologies

So I got the lasered anodised aluminium on Saturday! It was a bit disappointing to be honest, the colours are all over the place, with bluish and yellow tints, grey spots, even some scratches. I'm hoping to be able to rescue it somewhat (or at least homogenise the colours) by using a product called Rub N Buff. Basically a metal paint, which I'm hoping will stick to the exposed aluminium and not teh anodised black surface. If that works, I can paint it on, rub off the top and bring the markings to a consistent colour. Here's hoping!

In the meantime, here's an image of the top in place, with obviously a lot of work to be done to the wood supporting it, and also the metal still needing to be CNCed to cut out the circles.

I've also tried my hand at come leather carving for the piece of leather that will surround the barrel. Not very succesfully, but it's just my first go, and I rushed it a bit. I even stopped halfway through painting it as it was only a test. Will have plenty more fun trying to improve! Not sure about the final design I'll use just yet, still working on it (suggestions welcome!).

So the vegetable tan leather came this week and it's h-u-u-u-uuuge! Am gonna have to find other leather projects to do to get through all of this... 

Am also thinking of updating the design, moving away from the copper bands and possibly carving the leather instead. I've cut the barrel sized piece out of it, leaving a bit of room to spare, so if I carve, and if it shrinks, it will hopefully still fit (I dunno - never done this before!). If not, it's just a case of a light trim. As I said, I'm playing around with some design ideas, and here's the first of what is sure to be many. Very rough, just seeing how it might look. 

To be honest, I'm not sold on it.
So a big day on Friday. I got the cut pieces of the anodised aluminium back (thanks Robert Clarke!), and also the CNC'ed rete was delivered (thanks

As you can see above, the colour is quite disappointing in the etching, ranging from blues to yellows, so I decided to stain it using some rub n buff to homogenise the colour. This was also in line with the original intention of making this an aged, distressed looking piece. It was starting to look too precise and modern anyway, so this was a good call I think., a great job done and lovely to deal with. this 615mm diameter 3mm steel design cost €233 after VAT and delivery charges.

It's finally time to start putting it together and seeing how it looks. While only a mockup as I haven't prepared the wood for it yet, it still gives a good idea of how it's going to look. 

So here it is, the first mock up of the entire table! (sans glass which I haven't ordered yet, and the wooden dome which will be used to spin the rete, which I haven't made yet). I have the ball bearings under the rete and it spins beautifully with the weight of the steel. VERY happy with it!

Finally getting to put it together and see it as a table.

The rub n buff was called Ancient Gold, and it's a nice look, though the rete is now looking very stark against it and the steel is not really working as a final colour. To fix this, I've decided to go with a copper stain for the steel.

I haven't done it yet though, as I have to get my hands on the paint, and also I have to figure out a way to get the markings I want on the mild steel rete (yes, the issues never end!).

So onwards and upwards, it's starting to come together nicely. At this rate, I should have it done before Christmas. Given I started in April... that's ooh... what now? Far too long. That's what it is. Far too long!

So here's a short video showing it in action. Imagine there's a hemisphere attached to the rete, and this hemisphere will poke though the glass top in order to allow you to grab it to spin. As you can see, even in this mockup it appears to be working quite well! The weight of the rete itself makes for smooth motion when spinning. I'm pretty happy with it! The scraping noises at the start should be gone once I clean up the wood and glue it all down, etc.

So got another step along the road this weekend (30th October 2017). Looking at the table once assembled, Sharon very kindly opened my eyes to the fact that the table wasn't working AS A TABLE. I.e: The base with the hinge on it was preventing you from really putting your feet under it and using it as a table. It just got in the way. As heartbreaking as this was to admit, she was right. The base - and the hinge - needed to go. After all that work! Serves me right for not following the basic design rule - "Form follows function". Also, we were both now loving the pale plywood contrast to the metalwork and when I tried it with the yellow oak, it all just disappeared and wasn't nearly as interesting. Time for the oak to go. It'll just have to get reconstituted in another design down the road (how that hinge will fit in anywhere is beyond me though!).


What now?

Well, the barrel and the rest of it could still be saved, and also still used in the final design. With the oak gone, a new base will be needed though. We're both thinking feet underneath it will do, and then to just leave it as a floating table.

It immediately works better, much as I hate to admit it. 

I also had an epiphany about the glass. I was concerned about having a lip around the edge of the table to prevent the glass from falling off it, but as the intention is to still have the hemisphere "sun" shape in the middle, which will protrude from underneath and through the glass, it will also serve as a stopper. Added to that, I could add a leather stamped trim around the edges of the table top as additional support. So that's the plan.
This means I can simply place the glass on top. Obviously I didn't want it to sit on the metalwork, scratching the surface, so I set about inlaying the surface to prevent this.

A €38 euro router from Lidl and an hour or so later...

Took a while to get the metal pieces inlaid perfectly, had to take a dremel to the edges of the metal, and also trim down the edges of the inlay until the metal pieces snapped into place. Took half a morning.

I now had to route out a bed for the bearings to sit in. I marked it up and cut it out to what I hoped was the correct depth.

I added a little finger "access point" to be able to take it out again

Once this was done, I also needed to cut a hole in the base metal disc to allow the new inset bearings to poke through.
I needed to get a new 14tpi (teeth per inch) bandsaw blade in order to cut through metal, as my current one is designed for wood. McQuillans had one for €14.

This was painstaking and exacting work.

Perfect fit! The top of the bearing sits flush with the base disc.

The rete in place, spins nicely! I painted it up to a gold colour, but am not happy with it, and going to try to get in a lighter gold just as soon as I can get my hands on the right colour paint. At the moment it's a bit lost. It still needs the numerical detail added to it, but as of yet, I haven't figured out how to do that. Nothing like a challenge, eh?

The sides of the table top still need to be glued down to each other, and then the leather strip added around it. This should clean this off nicely. Also, I still need to do the leatherwork around the bse, make the feet, and get the glass! Oh, and make the sun piece for the centre. And protect the woodwork with a varnish of some sort... and stain the leather... and figure out and then stamp the designs.. the list is still endless.