Compact 5 Steady

Hi All,
First a short introduction:
I am Tristram Budel, I have been an instructables member for quite some time now but never uploaded a completed instructable.
I have a bachelor in chemistry and a passion for machining.

I still have my first Lathe, it is a very portable Emco compact 5. I have noticed that there are loads of these compact 5 lathes out there but unfortunately Emco has stopped the production of these fine hobby machines and I have found that high quality accessories are hard to find. Long ago I have equipped this small lathe with the original steady, which so far I might have used once or twice. Because it is absolute rubbish. 

In this build I am going to share how I build a new steady for my Emco Compact 5 lathe.
Total cost: about 15 euro's in materials
Total shop time: about 7 hours
Total design time: about 3 hours

General rules of thumb:
Safety goggles
Gloves
Earplugs
Organic vapour mask when cooling with ethanol
Remove chips and cuttings with a dry clean paintbrush
Always clamp your work piece in a machine vice when tapping or drilling
Always use some cutting oil when tapping or drilling

Attached you will find all my G-code files, these work fine with EMC2 (thats what I use) mind you that the feed speeds in the files are much higher as recommended. I reduce the feed speeds to my liking in EMC2.

Materials needed:
Aluminum stock 6060 10*100*150mm
Tool steel stock 10*10*300mm
6pcs M5*20mm hex socket screws
2pcs M5*30mm hex socket screws
3pcs M3*8mm hex socket screws
3pcs bearings 4x10x4 rs-components order nr 612-5802


Tools used:
Wabeco LF1400HS CNC mill (my pride and joy)
Hand drill
Bench drill
Hack saw
Some 80,250 sanding paper
M3 tap
M5 tap
6mm solid carbide flat end mill
3mm solid carbide flat end mill
2mm solid carbide flat end mill
Calipers (ofcourse)
sharpie
4.5mm drill bit
2.5mm drill bit
5.0mm drill bit
8.0mm drill bit

Hammer + small aluminium round bar (I know not very subtle but it works)

Programs used:
Google Sketchup Pro 8
CAM program
EMC2 Linux

The design:
I started out measuring the original Emco steady and transferring the measures to my sketchup drawing. I wanted a 20mm wide outer ring to provide the desired stability. And all parts should fit on the stock materials I already have.
I decided to use some leftover 10*100mm material 6060 aluminum, this is a nice tensile strength  easy machinable material.
I also had some 10*10mm tool steel stock leftover. So all parts are designed to do with these materials.

I used sketchup only for the basic design. I have found that Sketchup is a very nice program for when you want to draw some thing quickly, see how it looks, make quick changes, fit parts together etc. But if you are using any wierd measures and high accuracies sketchup length snaps and leaves you with inacurate drawings no good for exporting. By wierd measures I mean figures in the 0.001mm range, it does 1.000mm just fine but 4,376 not so much.

So after finishing the design insketchup I redrew it in my CAM program
Assigned mill paths to the different operations and exported the G-code files

Load stap 1 3mm flat end mill (yes I am Dutch, we say “stap” instead of step)
Zero the mill on the material
And insert a 3mm flat end mill with center cutting
Start the milling sequence
I milled this part with a 3mm 3flute centercutting solid carbide slot mill @ 7000rpm and a feed rate of 150mm min. with a plenty of cooling fluid, (ethanol techinical 99% denaturated  with 3% iso propanol, so in reality 96% ethanol with 3% IPA and 1% probably water)

Load stap 2 6mm flat end mill 
Zero the tool hight and run the milling sequence

I used a 4 flute 6mm solid carbide center cutting slot mill, 3000 rpm 300mm min feedrate and plenty of cooling fluid.

The cooling fluid when milling aluminium is not so much for the cooling of the part as for the the keeping the aluminium from sticking to the cutter. for me Ethanol works great, leaves no stains, no rust and no other residues. Also it washes off quickly and evaporates quickly. Unlike using cutting oil which will stick to your part probably for ever.

After the machine milled out the centre circle I paused the program just for a bit to clamp down the part on the other side so it wont fly off during the cut off.

When the part was done, brushed off.
I drilled the holes and taped the thread.
For tapping I cheated using a hand drill

For the two small supports see the next step

Mill the supports using a 3mm flat end mill
(I used a 3 flute center cutting solid carbide slot mill with a 3mm shank)
7000rpm @ 150mm/min with plenty of cooling fluid

Stap 1 mostly focusses on the holes and the milling in the x direction.
Stap 2 is the cut off operation, it will first cut of the right side. After the right cut of I paused the machine to clamp down the parts on the part its self, putting a piece of leftover plastic in between to prevent damage to the part.

I have no idea how these are called in English, in Dutch I would refer to them as "vingers", fingers in English.
We will need three of these

Clamp down the 10*10mm steel stock and align your machine to the right side of the stock as shown in the pictures
insert a 3mm flat end mill
Load stap1 bril3
(I used a 3 fluted centre cutting 3mm slot mill with a 3mm shaft)
7000rpm @ 120mm/min feed rate, using compressed air to blow away the cuttings

Load stap2 bril3
Insert a 2mm flat end mill
(I used a 3 fluted centre cutting 2mm solid carbide slot mill with a 3mm shaft, make sure you have at least 7mm of cutting length)
7000rpm @ 50mm/min feed rate, using compressed air to blow away the cuttings

After the cnc machining I un clamped the work piece and decided that a total length of 65mm would be a nice length, using my callipers, a sharpie and a hack saw i cut them to length. (yes this could have been a cnc operation too)
Next I used some 80 grid carbide sanding paper to undo most of the damage I did with my hack saw and finished with a 240 grid.

Then the part was clamped in a light machine vice and but under the bench drill to drill a 2.5mm hole all the way through the mounting stem. Next I tapped a M3 thread in the hole using my hand drill.
I used the 8mm drill to remove the burrs from all the holes. Then I fitted the bearing on the stem, for this I used a hammer and a piece of aluminium rod. (I started out with pressing but since the parts are so small a few gentle taps on the aluminium rod worked best)
To be exact:
Put one of the M3 screws through one of the bearings and screw it on/in the stem, lightly to avoid damage to the screw.
Remove the screw and put the part on the workbench/anvil stem up.
Place the aluminium rod on the bearing and gently tap down the bearing.
Insert the M3 screw and tighten

Last but not least three clamps
Stap 1 using a 3mm flat end mill predrills/mills the holes
7000rpm @ 50mm/min feed rate 3fluted centre cutting solid carbide slot mill, with compressed air to remove chips

Stap 2 using a 6mm flat end mill does the rest.
3000rpm @ 120mm/min feed rate 4 fluted centre cutting solid carbide mill, with compressed air to remove chips

drilling the holes all the way through using a bench mill and 5mm drill

hehe, I realized this instructable is incomplete without the most logic and last step.

Screw everything together

See it in action: