Getting Ready to Modify K40 - Tips?

Also on @donkjr 's blog.

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Great to see so many people jumping in here :smiley:

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@TwelveFoot This may also help: Don's Laser Cutter Things: Understanding the K40 Digital Control Panel???

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Looks like a cool machine, What are you guys doing with them?
Thanks
John

Thatā€™s what the Created With Laser category is for! :smiling_face:

Can anyone help explain how I would go about adding a couple of outlets to the back of the unit? I would like to have on/off switches on the control panel for each outlet.

Iā€™ve been looking online and I just canā€™t quite seem to find what I am looking for.

I used a relay module that is controlled by switches on an auxiliary panel to control outlets.
I set these up so that they can be controlled by software and/or panel switches.

Look under the ā€œPower Controlā€ tab of this schematic

https://www.digikey.com/schemeit/project/k40-s-21-8SM4SO8200E0

I used a 4 relay module but you can find two relay versions.

If you need more customized version of what I did let me know.

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@donkjr that looks to be what I am looking to accomplish. I suppose I need to learn more about this, but I am unsure what role the relay plays in it and how exactly to wire them together.

On the schematic, does ST11 and ST10 in the top left represent a terminal block from the main AC? If so, do you just wire in neutral, ground, and hot into a terminal block and then distribute to the switches, then to each outlet?

Iā€™m confused what RY3, RY7, RY8, and RY9 are as well. Are those the switches on your control panel to turn the outlet on/off or do they represent the relay?

Yes AC power enters through ST11,10 and feeds the sockets and relays contacts.
ST10-11 is the distribution terminal block.

Description of wiring:

  • N, G is wired directly to all the AC sockets
  • The L connection is switched and therefore is routed to one side of each of the relay contacts.
  • The other side of the contact is connected to the corresponding AC sockets L connection.

Attached is a simplified drawing of the control of one device. Mine has 4 devices yours may have only 2.

The switches like SW1 are those on the panel.

This subsystem involves high power and voltage. Make sure to follow proper design, assy and safety precautions. Especially ensure that grounds are installed and checked before applying AC power to the unit.

If you need help with an actual design let me knowā€¦

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Did you put the terminal block right where AC comes into the unit or off of the main power switch?

Also, is the circled M indicating main ground to the chassis?

Youā€™ve got a 12V / 5V PSU coming off the main LPS, feeding the switches on the control panel, correct?

Is ā€œpower from LV supplyā€ meaning low voltage supply?

Forgive my ignorance, but what is the purpose of having the switch connected to a 5V supply?

Off the main power switch

The M represents a motor

There is no 12V on the LPS (Laser power supply)?
I did not wire the switch source from the LPS

Yes is means an available low voltage (5V) power sourceā€¦

I assume you mean SW1. SW1 switches 5v power to energize the relay.

@Dkwells the drawing I sent you is NOT an actual design it was intended to show a simplified picture of how it works. DO NOT use that to actually try and wire a machine.

If you need help on the actual design let us know.

The actual design will require:

  • Identification of what loads you want to switch and for each:
    • Input voltage
    • Current draw
  • Selection of:
    • relay board
    • switches
    • indicators
    • power supply
    • AC sockets
    • Wire
  • Design:
    • Draw up schematic and wiring diagram

It might be useful to review these links:

You wonā€™t be connecting your relays to a microcontroller but this video shows how a relay module works. Try and ignore the arduino references:

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Watch ā€œK40 - How to Control AC Devicesā€ on YouTube

ā€¦

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In the back of mine weā€™re 2 two wire outlets. I cut them plus some metal out and put a standard US style electrical box in. Then I wrote a standard receptor.

Watch ā€œK40 - How to Control AC Devicesā€ on YouTube

ā€¦

As you know I donā€™t have a K40, but I have laser interests with all the different machines. I noticed your comment on the safety interlocks. Iā€™ve disabled the door interlock on my machine so I can get better air flow. The front door is open an inch. You should have an understanding of the machines workings if you are going to hack it. If youā€™re working on it, youā€™re eventually going to fire it with the lid open.

Weā€™re synonymous on the ma meter anyway (8ā€™)

Take careā€¦

P.S. is there a common controller used in the general K40 design. Iā€™d like to read up on itā€¦ thanks.

Lots of people solve airflow issues without disabling interlocks. Lots of people do lots of dangerous stuff and mostly get away with it. Do not stare into laser with remaining eyeā€¦ You can decide what you do, but I will continue to suggest them. Disagreement is not debate, so letā€™s leave it at that.

I am not too enthused about a lot of typing tonight, so I will be brief.

First off: K40 Laser Conversion This documents the bulk of my adventure.

I did pretty much all you are thinking about and a little more.

I personally would recommend a Smoothie board instead of any of the clones. I have a friend who is using the Cohesion board and has occasional problems. Once set up. mine with the V1 Smoothie 5C has been flawless.

I have the camera and rarely use it. Might just be meā€¦

I do not use any sort of pointing device (laser) and have excellent results. I tend to use fixtures or cardboard masks to position the work. For instance I will accurately measure the object I am going to work on and put a layer in the job that relates to the part outline. When doing the job, I first pin down a sheet of cardboard and then cut just the outline. Then I place the part and then cut teh rest of the job. hope this makes sense. I can shoot s short video of my process and upload to YouTube

This shows a plaque in a cardboard alignment mask: https://youtu.be/-1khZVbbTFQ

You can see that I pretty much did everything else you mentioned.

I would buy a good lense and some higher quality mirrors.

If you want to make a metal insert for the control panel, I can CNC the metal and laser label it with Cermark. You buy the shipping and the cost of the metal. Minimal will be the cost.

FWIW, I never even bothered trying the machine out when I got it. I test fired it to make sure the HV P/S and tube worked before gutting it.

Beevo

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Thanks for the video. I wear glasses that are made of polycarbonate. They are safety glasses. I keep a pair of regular safety glasses around for those that arenā€™t sight impairedā€¦ :slight_smile: Like with guns, you need to pay attention or you could get hurt. People probably pay less attention driving their 3K lb cars around.

Again, thanks for the link. Kind of getting into controllers for some odd reason. Take careā€¦

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1, decide what you want on switches.
2, decide what voltage each item requires.
While some things can be controlled by buttons directly from the panel, how to control the whole mix is the test of ingenuity. Lighted buttons are usually 12vdc with single pole switches. That means you can only switch one item and it must be at 12vdc. So what about 5vdc or 120vac? For me I ran every thing thru 12vdc relays. This allows me to control DC, AC and unknown signal levels like laser enable and laser test.

Watch is video: ā€œK40 - How to Control AC Devicesā€