End of September update: progress has been made on a number of fronts!

I discussed the auto-fill circuit with a friend who is an electrical engineer. He agrees that in theory at least, an AC circuit is better than DC for this application: "The only potential drawback over an 'AC' based capacitance system is that the probe is always positive and the pot is always negative". In practice however, a DC circuit can be made to work with little or no compromise by limiting the current that passes through it. His suggestion is to use a bipolar transistor which, depending on the components, should limit the current to 1 or 2 uA. Lowering the duty cycle to 1ms per second by strobing the power to the probe may or may not be necessary. In any case, once a layer of scale builds up on the inside of the boiler, all electrolysis bets are off. To be continued when I get around to buying the required parts!

Something much more exciting: after a long delay because of things getting lost in the post, the POWDER COAT PAINT ARRIVED!

Time to build a paint stand! Two cross bars with pins to fit the holes on the top of the cover:



...and a pair of U-shaped legs formed with the bender.



Some quick welds...



...and the stand is done.



Unfortunately, I don't have much documentation of the actual powder coat process. I did it at a friend's shop and it was a bit of a mad rush. Also, because he is set up to paint smaller things, applying the powder took four hands, leaving none for the camera. As with most painting, the hard part is the preparation - you know, Saturday afternoon you decide to paint the living room. First you move out all the stuff: the couch, the tv, 10 years of magazines you never read etc., then it's cleaning and putting masking tape on all the trim and every last switch and electrical outlet, then Sunday just after Home Depot closes you realize you forgot to wash the &*^*%$ing roller and brushes last time so now your whole house is upside down until you have another free weekend... Can you tell I love painting?

Prepping for powder coat is still arduous, but the end result is so much more satifying. First, I sanded the entire inside and outside of the cover to remove every last trace of rust. Then, the part has to be completely de-greased. I started with a commercial water-based de-greaser and then finished with 99% isopropyl alcohol. Then it's into the oven so that the metal can off-gas. As this is mild steel, it turned a pretty color after what is essentially also an annealing process.



Applying the powder itself relies on creating opposing electrostatic charges between the paint particles and the part itself.



After application the part goes back into the oven to melt the polyester resin so that it forms a permanent bond with the substrate.

The date on the first drawing for the cover is the 4th of February 2017. So after eight months and twenty more minutes in the oven, this part is DONE! I think that we might just be starting to see some light at the end of this tunnel.

This is going to be a great machine.

Yay Canada!

(checks bank acct.)

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Teaser for the next installment of the build: 16' of former rainforest.

I love the fact that you are resurrecting this lever group.

MMnnn...

A teaser..... flaunted on Friday the 13th...was this date purely coincidental?

Ok....you've got me.

My guess (the only obvious one to me) is for portafilter and toggle handles...is there a prize?

Paolo wrote:Ok....you've got me.

My guess (the only obvious one to me) is toggle handles...is there a prize?

Can i play too? Cup surround / Top edging ?

Thanks for the update! Have been following this for a while, so much neat stuff here.

Lol, this is more fun than I thought! More clues...

I chopped up that fabulous piece of lumber and sent it out to be dressed at Atelier Clark, the cooperative shop wing of the Clark artist run centre and general benevolent force in the universe.

Back from the planer, jointer and shaper:



A close-up of the profiles.



Two squares, one with a round over, two different rectangles and one length of left-over.
Of course, I changed my mind on the design and had to laminate a some extra material to one of the profiles. After which I added shoulders to both sides.



Then I made a simple jig to hold the shouldered profile at an angle to the (ripping) blade.



And then I cut off a little tiny wedge that I know is useless, but wont be able to throw away.



On to the chop saw with a block plus a piece of round rod to set the length.
The rod is removed before the cut is made to allow space for the part to move away from the blade safely.
The circular form of the rod means that dust/chips can't get between the end of the stock and the block thus guaranteeing a consistent length.



... et voila, the rough part.



Rinse and repeat 21 more times.



And now I also have a lovely collection of wedgy off cuts that will never ever leave the shop.



Adding a matching shoulder to the top and bottom.



By now, I sure you have all figured out what this is for... but if not, here is a test fit.



A little head-scratching was required to come up with a quick way to chamfer all four corners so that they don't interfere with the inside radius of the sheet metal.



... finally, 22 cup warmer rail stops...



... which all have to be finished with a tiny round-over bit and some old-fashioned sand paper.



Home stretch! The tung-oil finish. I love this stuff. Non-toxic and easy to work with. Just brush it on, let it soak in and wipe off the excess.





And here, after about a day spent more in figuring out how to make them than actually making them, they are.

Very nice! That's the kind of detail I love to see and it will look terrific. Are the handles going to match this?