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.
 
3D Printing Failure
 
While attempting to make one of these:

I made one of these:

Shame it's not as useful.


Friday, 4 August 2017


A Bit of Leather Work

I made some new straps for this bag, using leather rather than a plastic version of leather that was originally used.






One of the original straps had just worn out:




While I was doing work on the bag, I also replaced the popper that was on a closing strap with a new one, as the old one had been bent out of shape: