Wednesday, 4 October 2017

Maslow Update

Maslow Update

The Maslow is now together:

This morning I moved the motors forwards so that the chains are more parallel to the work surface. Hopefully this will stop the chains jumping on the sprockets when I start cutting thicker material.

The router I am using is quite top heavy and this causes the sled to tend to tip backwards, especially if the router bit it out from the work surface. at the moment I'm putting a rod of steel on the top of the sled as a sort of counter weight. It works, so I'm happy at the moment.

I have made the first 'thing' using the machine:

Well, OK, it's the parts for a thing, not a thing, but this is the sort of thing the Maslow was for. Big plywood things. At first anyway, maybe big scaffolding board things later. These parts are going to be a filament reel for the 3D printers. I've made them manually before and this was way quicker. And I can do something else while the parts are cut out.

The calibration was a bit out before I moved the motors. I'll have to re-calibrate now the motors have moved, but hopefully I can get the calibration back to something as good as I had before. Those discs I made are slightly oval, but I'm hopng I'll be able to manually adjust that out on the next calibration.

The Z axis mount work remarkably well, considering the wood isn't actually attached to anything, it's just wedged in there.

I may have a go at 3D printing a replacement for the wooden version, but this works, so I'm in no hurry.

Tuesday, 26 September 2017

Prototype X-Y Table

 The new microscope came with a nice XY stage, but the slide holder was missing. I made one from a cheap XY table. The XY stage is manual, which is fine for adhoc looking at dies, but for photographing dies and then stitching photos there's a lot of photos. It's tedious doing it manually. So I prototyped an XY table from DVD drive stepper motor assemblies.

I had an arduino and two stepper drivers, so connected it all up;
The result is here, the two stepper drivers are being driven with the same signals.

And another view.

I'll have to make a stage block with a dovetail to mount this on the microscope. I may also remove material from the top table as it could do with being a bit lighter.

Wednesday, 20 September 2017

New Microscope

I've been looking at a lot of ICs under my microscopes recently, and realised that it was a way that I could do better reverse engineering. This will let me look at the ICs on a PCB without datasheets, so the PCB could possibly be re-used.
Reverse engineering the IC is an interesting thing in itself, as well.

So, I had a look on ebay and bought a metallurgical microscope. This has a lighting system that can illuminate a subject from the top, so it works on opaque samples like ICs.

It came with no objectives, so I'm now hunting for decent objectives for it. It has a proper X-Y table which is good for moving samples about. This is especially useful for die-shots which are large arrays of photos.

The USB microscope is still useful for soldering and so on, as this microscope has a working distance from objective to sample of between about 0.5mm and 10mm. That's not a lot of room for soldering!

The X-Y table didn't have a slide holder so I bought a cheap X-Y table mechanism on ebay and used some melted down food trays cast into an ingot :

After machining into a block, I drilled some holes and mounted the slide holder from the cheap XY mechanism:

So I now have a nice spring loaded slide holder:

It's not perfect, and has a bit of a broken drill in it, but it's decidedly better than my first attempt:

Thats a bit of sheet metal bent into a holder shape. It's much better now.

Next projects are a camera mount and an LED based illumination source.

Saturday, 2 September 2017

Maslow L298 Failure

Maslow L298 Failure

My Maslow motors stopped working, so I removed the IC from the PCB, decapped it and had a look. One of the transistors has overheated, maybe shorting some rails out:

For reference, the full chip looks like this:

Tuesday, 29 August 2017

From Scrap to Rings...

Starting with some leftover wood, I found some circles inside, using the bandsaw:


 It turns out that there were quite a few circles in that bit of scrap:

The circles stack quite nicely too...

I found some holes in the middle of the circles, as well...

We chose some colours and bought some sample pots

and went multicolour.

Saturday, 26 August 2017

Maslow Update

A short update of the Maslow. I've added the Z axis drive using a piece of wood, I'm planning to 3D print a thingie to replace the wooden prototype.

Unfortunately, while testing the Z axis I drove the motor into a jammed z axis screw and overheated one of the motor controllers, so I now have a Maslow that only has one motor drive.
I'm going to have to remove the drive chip and put a new one on...

Sunday, 13 August 2017

Maslow Arrival
My Maslow CNC router kit has arrived, so I have been making a frame for it. The frame is a one-off that fits on a wheeled trolley I made a while ago for sheet material storage. The dimensions seem to be absolutely correct for a Maslow frame, strangely, as I didn't build it with the CNC machine in mind.
The kit looks like this after it has exited the box.

The frame so far is a double A frame with some chipboard flooring for a sacrificial routing surface. (It's really cheap, which means it is comfortably sacrificial).

The A frame is constructed similarly to the standard Maslow frame, and I'm keeping the dimensions very similar even though I will be using smaller plywood sheets than the 8 x 4 foot sheets Maslow was designed for.
I'm planning on putting triangular motor mounts on the cross beam, hopefully they will be rigid enough for the motor/chain stresses. If not, then I'll look at a single beam across the top and supports. I'm using up a lot of material I have hanging around, hence a different design and varied materials.