Let me untangle my Spaghetti – Clem’s Numerical control

As teased in the previous blog entry, the dreaded wiring of the control box insides is my next task.
Can there be any more infuriating than cutting crimping and soldering a massive amount of wires.
Well there can if you are a leftie and have to rely on crimping tools made for right handed people.

My solution for surviving the right-handed-centric world of crimping is to place the crimping tool in a vise and to use it like a stationary device, there are still missed crimps, but at least most of them work as intended.
I have to say my tools are non branded cheap tools that came with the terminals when i ordered a box of various sizes, so I would not expect much performance from them.

Maybe its time to invest in a good set of crimping tools. Let me know which ones are your favorite!

In analogy to the stepper output wires I also keep the wires going into the stepper drivers in one color, separating them more might come in handy when debugging, but I don´t see the benefit outweighing the added cost of ordering 6 different wire colors, especially since my favorite cables only come in the greyish-black and orangish-red shown in the pictures. So I´d have to find suitable alternatives first, which also eats into my time schedule.

Considering time wasted with searching for parts and mounting troubles in a professional context is crucial to keep the operation profitable. Even tough I build this machine for myself and not a client I have to take this into account because I need to spend most of my working hours on new Element14 presents episodes and product development. So every minute wasted with failed crimps or snapped wires is really eating into my already tight schedule.

The curious viewer will spot that I used end ferrules on every single wire, loose strands are a no-go and I’d rather spend money on ferrules than on replacing burnt components from little oversights.
Matching ferules to the right cable size is not always trivial as they seem to be mostly made for AWG sizes and not metric cable sizes. Which makes them look snug after crimping but they can still slide off.

Especially on the very thick cables I used for the power connections I had to thin down the strands a bit to get them into the largest ferules possible that still would fit the screw terminal on the boards.

This tradeoff seems rather janky to me.

So what is the professional way to do this?

I suspect it has a lot to do with choosing the right terminals and cable sizes and with fixed component output terminals finding the biggest common denominator in cable size.
But Iḿ a bit restricted in what I have so I´d rather use up stock of cable that is total overkill and thin it down at one end to make the connection, than spending the money on thinner cable that might be just enough for the current it has to carry.

The numerous switches on the front panel (see last blog post) have no fixed function yet, I´d like to use the machine a bit and then wire up the functionality I deem useful during operation. Maybe the fans don´t have to get a shortcut via switch but cooling pumps need it to avoid risk of flooding.
Maybe homing needs a quick shortcut, we will see.

Does any particular function come to mind that you would not want to miss directly on the front panel?

After a quick adaptation with the hacksaw, the case was finally ready to close it up.

The next task will either be a redesign and re fabrication of the fixture we decided upon in the first blog posts a while ago, or wiring up the motors to the control box.
Either way, I also have to think about safety enclosures, and will probably use up some big scrap aluminium clad epoxy plates I have laying around. And making a template for the cutouts and drills might be not that easy for such a big device.
I could either learn how to divide up a drawing on multiple sheets of A4 printout..or try to get the plotter going that's collecting dust for the last year, to maybe be able to directly draw on bigger paper. Even the laser is an option.
In either case the plates will be bigger than any work area of machines that I have, and my manual woodworking skills are a lot lower than sub par...
How would you approach this problem?

I hope we get this hunk of metal going soon it seems the tiny tedious tasks on the inside have no end.

This blog is a part of Clem's CNC Control Project.  Click the Previous button to jump to the previous blog in the series.