Tag Archives | milling

Brasilia Espresso Machine Restoration and PID Upgrade

I’ve been working on this project on and off for a few years. It started off as a simple restoration of a second hand Italian espresso machine which quickly got out of control, as most of my projects seem to do. Here’s a video showing the finished project and then a bunch of photos showing the build. I should have done the video with the camera turned the other way, sorry about that but I couldn’t be bothered re-doing it.

The Brasilia ‘Lady’ is a very simple single-group, single boiler machine. It has a 300ml brass boiler with a 3-way solenoid valve. It has a simple bimetallic thermostat which means the temperature swings wildly (although some models do have more complex thermostats). My model had no micro controller and was purely AC driven and controlled by the buttons on the front and the thermostat. The machine is in some ways very similar to the popular Silviamachine.

When I started restoring the machine I quickly decided that I wanted to do a PID modification to maintain a constant temperature. At the time I had just started playing around with Arduino so I thought why not just take all of the AC buttons on the front down to an Arduino and control everything through software with solid state relays for the pump, boiler and solenoid. The pictures and captions below should explain each part of the build sufficiently.

TLDR: Final assembly photos are at the bottom of the post.

Machine Housing

Case01

This is how the machine started out. This isn’t actually mine but I didn’t take a photo before I started. Mine was in much worse condition.

Very simplistic internals.

Very simplistic internals.

 

Case02

Case03

case04

There’s a lot you can do with a good set of files

Top Panel

TopPanel01

Template for top panel created in SketchUp

Template printed onto toner transfer paper

Template printed onto toner transfer paper

Thanks to Katt for the great idea of using PCB transfer paper for metal work.

TopPanel03

Template pressed onto 3.5MM aluminium plate with an old sandwich press

TopPanel04

TopPanel05

TopPanel06

Milling the display aperture and a recess so that the display is very close to the surface of the panel.

This Sieg SX3 mill is proving to be very useful. It’s the same as the Grizzly G0619

TopPanel07

TopPanel08

TopPanel09

TopPanel10

Polishing compounds in various grades

The polishing compounds came in a set of 12 syringes

TopPanel11

Shiny!

 

oLED Display Module

Display02

 

Display03

Display04

Display05

Display06

Display07

Display08

Display09


Display95

This 3M Double-sided tape is super strong.

Display10

Display11

The clear acrylic lens is sealed to the display module with 3M double sided tape.

 

Display12

Display13

 

PCB and Controller

PCB design created in KICAD. Such an awesome piece of software!

PCB design created in KICAD. Such an awesome piece of software!

Controller01

12 double layered PCBs delivered for $14 USD from DirtyPCBs.com. I’m not complaining!

Controller02

Controller03

Controller04

Controller05

Controller06

Controller07

 

Power Box

PowerBox01

 

Front LED

Led01

Led02

The led holder is made from stainless steel. A piece of fiber optic plastic is glued in as a lens.

 

Water Tank

Tank01

Tank02

Tank03

Tank04

Tank05

Tank06

Tank07

 

 

Water Inlet

WaterInlet01

WaterInlet02

WaterInlet03

WaterInlet04

WaterInlet05

WaterInlet06

 

I’m not sure why I made such an elaborate nut for this considering it’s hidden inside the machine. Never mind it was fun.

WaterInlet07

WaterInlet08

 

Final Assembly

Before the final assembly I had the machine casing stripped and powder coated in flame red.

Assembly01

Group head temperature probe

The group head temperature probe is held on with High temperature Kapton tape

Assembly02

Assembly03

Assembly04

Assembly05

The tube wrapped around the boiler is a pre-heat tube that I added so that the water being drawn into the boiler is not stone cold.

Assembly06

Assembly07

Assembly08

Assembly09

Assembly10

Assembly11

Assembly12

 

Assembly13

 

Final

Parts List: (Thanks China!)

  • Top plate: 3.5mm Aluminium (from HP Server blanking panels)
  • Display module: Cut from a block for 101 x 50mm Aluminium (New, local)
    • Display: Hide.HK I2C 1602 LED display. (via eBay ~20USD)
    • Display glass: Plexiglass 1.5mm (via ebay)
    • Display Tape: 3M 300LSE 9495LE Double Sided Adhesive  (sheets via AliExpress)
  • PCB printed by DirtyPCBs.com
    • Arduino Clone: Nano 3.0 clone (via AliExpress)
    • 2x Temperature sensor chip: MAX6675ISA SPI Interface (via AliExpress)
    • Connectors (via local JayCar Electronics)
  • PCB Box (via AliExpress)
  • Power Box – Aluminium (via local JayCar Electronics)
    • Solid-State relays (Can’t remember had bunch in a parts box for years)
    • DC power supply: From a Samsung USB charger
    • Rubber grommet kit (via AliExpress)
  • LED holder: From some stainless rod I had lying around
  • Water Take outlet: Stainless M10 Bolt
    • Silicon seal for water inlet – from a kit (via AliExpress)
  • Water inlet: 22mm Aluminum rod (New, local)
  • Silicon tube: 6x9mm food grade (via AliExpress)
  • Pre-Heat tube: 6.4mm (I think) copper (New, Local)

 

Thanks for stopping by. Feel free to ask questions.

Here is the source code and PCB schematic designs if anyone is interested. I’d be happy to have critique on either.

uCespresso PCB
Version:
Updated: 2015-07-21
Download: uCespresso PCB.zip - 334.13 kB
uCespresso Arduino Code
Version:
Updated: 2015-07-21
Download: uCespresso 0.75 Code.zip - 25.2 kB
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First attempts at milling (and mobile blogging)

Here’s my first attempt at making something with the mill. Also my first attempt at using the WordPress mobile app to post. If this is easy maybe I’ll post more regularly. Micro-blogging I think they call it?

image

This just started out with milling into the body of an old HP harddrive to get a feel for the machine. Very high grade aluminium (I presume). Very easy to mill.

After a while this is what I came up with.

It’s an adjustable bracket. I think. For what? I’m not sure.

This is very exciting. The only limit is imagination…..I imagined an adjustable bracket. Oh that’s really sad!

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Milling Machine Bench and Workshop Update

I’ve recently acquired a couple of significant additions to my workshop so I thought it was about time I did a workshop update post.

These two new additions are one Sieg SC4 metal lathe and one Sieg SX3 milling machine. The latter of these two weighs 165Kg (363lb). I didn’t like the idea of having to move this machine more than once so I thought it was appropriate to build a sturdy bench on castors which I could put the machine straight onto upon receipt.

The SX3 Mill is also sold is a Grizzly G0619

I got these machines through Sieg Machines New Zealand. They stock and source a wide range of machines and accessories. Chris the owner has been very helpful. Check them out at www.sieg-machines.co.nz

 

As with most of my projects, the bench ended up being needlessly over engineered! I conclude that I have Inceptionitus. I.e. Once an idea has taken hold of the brain it’s almost impossible to eradicate’.

In this case the idea stemmed from the thought that eventually I would convert this milling machine to CNC therefore I’d want a way to contain swarf and cooling fluid. Initially I considered forming a tray using some kind of rubber lining like butyl rubber membrane, but I was concerned about chemical resistance.  Then it occurred to me that a moulded fibreglass tray would be a ‘simple’ solution to the problem. And that was it, the idea had taken hold. Of course it’s much easier to conceive an idea than to complete a project! Let’s begin…

 

First step – Get the dimensions of the machine and create designs in Sketch-up.

TrayMold

Mould design for the fibreglass tray (Inverse of the final product)

 

 

BenchDesign

Overall bench design

 

I decided to make the fibreglass tray first so that I could adjust the bench design to accommodate for any inaccuracies in the fibreglass which once set can’t be adjusted.

 

The mould was made from:

  • 9mm melamine board
  • Scraps of cupboard door chipboard laminate
  • 20×45 Pine cavity batten
  • Plasticine
  • Duct tape
  • Polyester builders/auto filler
  • 6mm MDF

 

MouldMaking2

MouldMaking3 MouldMaking7MouldMaking5  MouldMaking10

 

This was a stupid way to make the drain hole. If I did it again I’d use the top section of a soft drink bottle or similar.

DrainMaking DrainSand

DrainDone

 

I did a few test pieces of fibreglass to get a feel for the gelcoat which I hadn’t used before. And to work out the best tape to use. I found that the resin sticks least to the duct tape. Masking and packaging tape were also fine but the heat from the curing process made them wrinkle.

GelcoatTests

 

Plasticine is used in the corners to give a radius. Fibreglass doesn’t like bending at 90 degrees.

MouldPast

 

I put tape over the plasticine on the long stretches because it gives a nicer finish than the plasticine.

MouldDone

 

Two coats of gelcoat brushed on with a a couple of hours between coats and left to cure for a few hours.

GelcoatDone

 

After the gelcoat I laid down a single thin layer of fibreglass re-enforcing with polyester resin and allowed it to fully cure and then sanded it. Doing this (as opposed to adding multiple layers straight away) significantly reduces the chance of getting air bubbles between the gelcoat and the fibreglass.

After this three more layers of resin and chopped-strand-mat reinforcing was added. I ended up with a few air pockets in these layers but nothing too major. Perhaps I should have let each layer to set up at least a little before adding the next.

FibreglassDone

 

Edges cut flush with a diamond blade on the angle grinder then smoothed off with a normal disc.

MouldGrind

 

I naively thought I would be able to remove it from the mould without disassembly. Yeah right!

MouldDissasembly

 

TrayDone

As expected there are lots of moulding artefacts but overall I’m very happy with it. Especially considering it was a fairly rushed job over one weekend and a few week nights.

MouldingArtifacts

 

Now on to the bench itself…

The bench design is based on the same torsion box design as my main workshop bench.  Pretty overkill but I still had a lot of plywood offcuts from the workshop restoration that I needed to use up.  There are castors on each of the four corners rated at 280Kg each. The centre foot jacks down with three 16mm bolts.

Bench1

Bench2

 

Bench2-1

 

I was able to recycle wood from the fibreglass mould to make the fixing blocks for the bench top.

Bench3

Bench3-1

Bench4

 

I used auto filler on the rough edge of the tri-board to give it a smooth seald finish.

Bench5

 

And now for the best part…the install.

Finals3

 

Finals4

Finals1

 

Finals5

On the left: Sieg SX3 milling machine. On the right: Sieg SC4 lathe

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Thanks

Special thanks to my wonderful wife who painted the bench, to Simon for the help and use of the engine crane. And to Andy for the offer of the engine crane. To Chris at www.sieg-machines.co.nz for all the help. And to Adam who transported the machine.

And a plug for my favourite local businesses:

NZ Fibreglass, always with helpful advice and Hill Lumber who have the best lumber prices around

 

Conclusion

Things I’d do differently:

  • Contouring the tray and drainage area to make sweeping swarf away easier
  • Take more care on the mould to reduce the moulding artefacts
  • I’d consider making a reusable fibreglass mould so I could make more trays and sell them – although I suspect the market in NZ is fairly small
  • I probably wouldn’t bother with the jack’able middle leg and just use casters instead. The cost of the large bolts wasn’t much cheaper than the casters in the end. Arguably it provides more strength to the structure right under the machine. Arguably the middle leg is overkill and not needed at all!

Thanks for stopping by, hopefully this gives you some ideas if you’re thinking of doing something similar.

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