[stragenmitsuko]

I'm gonna have a go at at a small router .
Mainly aimed at drilling pcb . I am an EE .

Let me start by showing off my equipement .

I have a lathe , a mill , a drill press , a mag and a tig welder .
A clarckson MKII tool grinder , that one cost me an arm and a leg .
And lotsa hand tools and small machines like sanders saws etc .

Anyway , enough to keep me busy

[stragenmitsuko]

So what's with the junkyard then ?

I plan to build this machine from scrap .
No fancy lineair rails , no commercial stepper drives .
If I can avoid it , I won't even buy a single piece of aluminium .

I do have the advantage that I regularly have to dispose of old lab equippement . Centrifuges , autosamplers , you name it. These machines often have aluminium internals , stepper motors , bearings and parts like that .
I usually keep things of wich I assume I can use them someday .

There's also a metal recycling plant nearby . That's where I sell the pieces of metal I don't keep .
Quite often bars or plates' of alu , brons , stainless can be found there .

Some pictures of my garage filled with "useless" junk , as my wife tends to call it .

[stragenmitsuko]

The base :

I found this nice 255*300mm ( 10" by 12" ) aluminium box in my attic
It's from an old sc/mp uprocessor development kit .
Late 70's early 80's , something like that .
Has a nice national semiconductor tag on it .

It has about the right dimensions for a small pcb drill
I'l use this box to house the electronics , and the router wil be like the lid of the box .
Oh , btw , I'm dutch speaking . So forgive me if I sometimes use odd english .

[stragenmitsuko]

I found this 400*900*6mm (16"35*1/4) alu plate at the metal recycling .
I only need 300*255 , so I used a carbide tipped hack saw to cut a piece
of approx that dimension .
300mm is about the maximum travel the saw has .
But it sure beats cutting it by hand doesn't it ;

Then I put it on the mill to square up .
I don't have enough Y axis travel to square it all at once .
So I had to dial in 3 times .

Having to dial in anyway , I took off the universal head so that I
could use the horizontal spindle . Makes it easy to clamp the plate on
the table .

Once squared up , holes were drilled and taped to put on the front an back plates later on .
Picture shows the use of an oldfashioned machanical edge finder , and the center drilling of the bores .

[stragenmitsuko]

While the universal head was off , I made the supports for the x-axis slides .

These 10mm( 0.4inch) square rods weer salvaged from aluminium wndows and doors .

Drilled and tapped them to be bolted to the base .
Later on I'll use a ball mill or a v-groove mill to put on the slides .

[stragenmitsuko]

Time to put the universal head back on .
And to dial it in .

Put the base back on the table , and dial it in .

And then I milled two slots , where the slide supports are supposed to come .
The slots where drilled to match the previously machined supports .

[stragenmitsuko]

Next I'll be drilling the holes in the x-axis supported rails .

I've got these nice 22mm(0.9") hard chromed and polished
rods. Sounds expensive right .
Not at all , they were salvaged from a pair of worn shock absorbers .

And a picture of the finished base plate .


That's it for now .
More to come within a few day's .

[gmfoster]

Just watching, looks great so far. Nice mill .

[stragenmitsuko]

Today I countersinked the bolts that hold the rail supports and put the supports on .
These bolts are temporarily , only to be able to machine the v-groove for the rail . Once finished , the tapped holes will be drilled to 6.5mm( 1/4) and the
rails will be bolted directly to the supports .

The machining of the v-groove is quite critical , and will be done once the x-axis sliding block is finished .
So the base is on hold for now .

[stragenmitsuko]

Time to machine the rails .

Both ends are treaded .
Don't need those , so I cut them off on the lathe .

Then the rails were center drilled , and drilled with 5mm .
There 's a hole every 35,5mm ( 1.40" ) .
Nine holes a rail , two rails , it took me a while .
Surprisinghly the hard chromed rail drilled pretty good .
I was a bit worried drilling trough the chrome would be tough .

Next tapping the holes .
I don't have a tapping head .
So in order to tap straight , I use this simple trick .
Most tapes and tap holders have a center point at the end .
It's there for a reason .
I took a 10mm ( 0.4") rod , and machined a 60° point at one end on the lathe .
Then I put it in a 10mm collet in the mill , and tightend the collet just enough to allow the rod to slide up and down .

I grab the rod with my left hand and push it down on the tap holder .
With my right hand I turn the tap .
Poor man's tapping machine maybe , but it works like a charm .
Works also in a drill press btw .

The result is a dead straight and perpendicular tapped hole .


Quite pleased with the results .



I've got an engine swap scheduled on a vintage audi the next couple of day's . Won't be machining much till Friday .

[Jesse B]

Looks pretty cool so far.

[stragenmitsuko]

For the x-axis sliding block I need quite a beefy piece of aluminium .
60*37*255mm ( 2.3*1.4*10) .
Wich at first I didn't have , so I thought I'de weld something up .

But then I remembered this .

This was once a biopsy cutting machine .
Used to cut samples of tissue of only a few microns thick .
Afterwards these cuts could be studied under a microscope .
This one had to go , so I trashed it , but kept the bottom plate .
It's almost solid aluminium , exactly what I need .

The carbide tipped shorten saw didn't like these heavy cuts . I really ought to get me a bandsaw
someday . Anyway , I cut it up in some handy pieces wich I'm sure will come to use later .
And the center section is exactly what I need for the x sliding block .

Should be fun squaring up

[stragenmitsuko]

The downside of using scrap material is that there are alway's some
unwanted bores or slots .
They don't necesarily interfere with anything . But it just doesn't look
good .
So I machined some plugs , pressed and welded them in .
I'm not the wolds best welder , but when the excess material is milled off , it doesn't look to bad .

Then the block was squared up and milled to size .
Somehow I just can't seem to produce those bright shiny finishes
some people can .
I've tried various speeds and feeds . Dry and wet cut's .
Those mirror like finishes I wonder how it's done .

Finally , I made the 28mm ( 1.10") bores wich will receive the lineair
bearings .
I don't have an iso to morse taper . So I driled it with 16mm , the largest drill I have with a staight shaft . And then I had to use a boring bar .
Time consuming process , but it works .

[Jesse B]

Somehow I just can't seem to produce those bright shiny finishes
some people can .
I've tried various speeds and feeds . Dry and wet cut's .
Those mirror like finishes I wonder how it's done.

It may have to do with the specific alloys used. I know that each different aluminum alloy machines differently; some are harder, some are softer. Some machine with nice glassy finishes, some don't. I assume that has something to do with it

[stragenmitsuko]

Yes , that is quite possible . Some alloy's are so soft , it's almost like milling a block of toothpaste . With chips stcking to the cutting tools , alway's ending up in rough surfaces .


Anyway , Iv' machined some bronze busses to be pressed in the sliding block .
These will be my bearings ;

They were supposed to be a very light fit .
I've knurled the surface , coated them with locktite and pressed them in .
WIth the knurling acting as miniature pockets filled with locktite .
The rason, for this is not to put any strain on the sliding block .

Unfortiunatly I must have measured something wrong , as the fit was rather tight . Had to press the min with the hydraulic press .
Took 3 ton to get them in , wich is way to much .

As I had feared , the tight fit caused a few tenth's ( mm not inches ) of warpage .
So I milled off the excess material to get it straight again .

THen all kinds of holes were drilled and tapped .
And the two sliding bores were made using the boring/facing head .
This boring head is a bit to large for my small mill .
With the boring head , and the cutting tool , I'm limited to 7cm (2.75") of y axis travel . Just enough to drill the block .

[stragenmitsuko]

A friend was kind enough to provide a 22mm ball nose mill .
I have to give it back offcourse , but I 'm very glad he allowed me to use it .
Far better then a v-groove .

So I gave the supports a final pass to clean them up and bring to to size .
And then I milled both 22m grooves .
For some reason , this finish is quite good .

Finally two slots were milled to the sliding block .

[stragenmitsuko]

Time to clean up , debur and put it all together .

The lineair slides are parallel down to 0.01mm .

The sliding block fits and moves at the tip of a finger .
I would have preferred it to be a tiny little bit tighter .
But it'll do fine .

[Jesse B]

That looks great. I'm surprised it took 3 tons to get those suckers in! :O

[RomanLini]

This is a cool thread!

Do you have a drawing (or even a crude sketch) of the machine configuration?

The build photos are great but it would be nice to imagine how the pieces are finally going to go together.

[stragenmitsuko]

I'm surprised it took 3 tons to get those suckers in! :O

Yes , that was way to tight .
I think I've pushed the zero button of the digital calipers when it wasn't at zero . Maybe some debris , don't know .
I was worried that it would warrp back when I milled the slots for the slide supports . That would have ruined the part as the slides would no longer fit the bores . Luckily that didn't happen .

Do you have a drawing (or even a crude sketch) of the machine configuration?

Not really .
I have it in my head , but that's kinda hard to upload .

Parts are designed in cad as I go along .
But I don't have an assembly drawing .