Sunday, June 20, 2010

Poetical Modesty, In Progress - Stage 3.

Welcome back!

Now that I've squared away the pulley system, it's time to dive into really uncharted waters.

A generous student from a workshop I taught in Sydney a little while back gifted me this little hand-made brass winding mechanism, which I have to assume is a fishing spool. The textural clack/purr of the ratchet mechanism feels and sounds so good that it sprang to mind as a model for my turn crank. It only turns in one direction, and the arched piece of spring steel at the bottom must be gently depressed to disengage it from the ratchet teeth and allow it to wind back the other way. Perfect for my glass panel, so it couldn't drop accidentally like a guillotine and destroy the piece.

The only trouble will be, um, to fabricate it.

I study the object to really understand it, then do some internet research to find out more about these devices, learning along the way that this is called a 'ratchet and pawl' system. The pawl is, in this case, the little rocking steel piece with a screw in the middle, held in tension by the steel tongue - this stops the ratchet from unwinding.

First to make the toothed gear.

As it's not going to be resting against a flat surface like in my antique reel, it needs a shelf halfway down the teeth. A British coin from 1806 has the perfect circumference so it gets soldered into place.

With all this sawing of thick brass, I'm getting lots of brass dust. Like the miser I am, nothing goes to waste - I'm collecting it to use inside future pieces. It looks like gold dust.

I design the pawl (the release arm for the reel). Searching for a suitable thickness of steel, I spy the wrench that came with my Ikea kids' chest of drawers that we got today and anneal it so I can saw it.



Forgot to photograph this object before I started working on it, but this nut came off of a 1950's clock pendulum, which I grooved, stepped and embellished to make it more elaborate.

The axle with the gear consists of brass tubing. One of the things I'm being mindful of is that like any good machine, it needs to be able to be disassembled.

A second British coin, this one from 1740. Now I've got two divided reels for each chain to wrap onto.

The fancy nut with the brass rod screwed in. This is what will pass through the gear/tubing to attach it to the structure.

Decorating the other nut to go in back of the piece. I need to make it adjustable and stable, so I decide to drill and tap it so I can make a tiny set screw to hold it in place.

This is already more 'machining' than I've ever done. Little do I know what's left to do.

Now I can assemble these elements and see how they fit. Though I'm still a long way off from being able to test this thing out - I still have no idea whether it's going to work at all. It helps to be an optimist.

Looks good at this stage. Now to adapt the candelabra to hold this crank. I'll begin by running a tube through the base and riveting it front and back.


The chains get soldered onto the shaft, then wrapped and taped up to keep them out of the way for the time being.

As it was made up until now, there is nothing to make the tubing turn with the crank, so tiny tabs are soldered onto the back of the crank wheel where it meets the tubing. I will then slot the end of the tubing to catch the tabs, as shown.

On now to attaching the pawl to the base. Because I don't know how far out the toothed gear will sit from the candelabra (it has that deep decoration, plus it's not straight up and down), I need to make an adjustable post that will hold the spring in place that tugs on the pawl, keeping its tension. So on to that. Here the wire has been twisted to harden and is drilled in the end.

Using a threading die.

Adjusting the rod.

Etching a date/signature into the back of the base.

Now all of my quiet excuses have run out to dodge the thing that has been making me most nervous during the whole project: dismantling the beautiful box. I'm a bit petrified it will get decimated and then won't be right for whatever reason. Well, I'm in this deep, there ain't no going back. Call in the demolition squad.

Note - I'm leaving at week's end to teach up in Rockhampton, Queensland for a week. I think internet is a bit sketchy at the venue, so I can't promise the fourth and final stage next week - it might have to be the following week. Either way, we're almost there!



Sunday, June 13, 2010

Poetical Modesty, In Progress - Stage 2.

Welcome back. In the last post, I created my first digital work on glass, then began the process of developing a stage-like machine in which to view it.

The mechanism of the piece is very important, as I want to see the motion of several wheels as the glass is raised and lowered. And for the first time, I am going to be making all the machine parts by hand, rather than using found objects. Combined with the found elements - the box itself and the candelabra base, I hope to make it a genuine parlor device.

A pulley system is what I need, so using my quick sketch as a guide, I make a careful rendering in Photoshop of the pulley wheels, referencing the crank I'd made earlier so they'd all work visually together.

The image of the pulleys is glued to my brass sheet, as with the crank, and I ready to drill and pierce the negative spaces out.

My trusty Dumore begins the work of drilling. I want a car with this wrinkle-paint finish.

Looks like I'll have my work cut out for me. I wish, actually.

Cutting out and shaping the mahogany discs that the brass wheels will embellish.

Creating an inlay area.

Dyed New Zealand paua shell is then sandwiched between the brass and wood. Here, the first of the four pulleys coming together and viewed on the drawing for the backing plate.

And the backing plates being prepped to cut out.

The tiny chain that I envisioned using as a drive belt would need some guides to be fed through so it wouldn't rub on anything. Here I'm bending some brass tubing for the job.

These little shapes will mount at the top of the structure for the chain to suspend the glass from.

One of the large pulleys about to get riveted together..

Brass wire getting decorated as one of the support rods.

The little brass guides are soldered in place at the top.

After all this prep it's a rush to sit the elements together so as to see the general structure taking form.

Setting it up as I pictured it in my drawing, the pulleys seem awkward in this position. This is why my sketches, when I do make them, are really rough and it's assumed they act merely as a launching pad, rather than a technical blueprint. I move the pulleys down the sides until the whole composition has the right balance. What a thrill to be working on something so large after my long absence from making larger work!

Looks like it will work well, but there are a lot of unknowns ahead. Setting it all aside for now, I set about assembling the two side pulley structures.

Curling the ends around to straddle the pulleys.

One side finished, I can't resist feeding the chain through and pulling it back and forth to see the pulleys operate. Good so far.

Next week: fabricating the chain reel & cranking system, and deconstructing the box. Tune in!