Improved K40 Operating Panel

K40 Operating Panel

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Your donations help fund additional research, tools and parts that I will return to the community as information.

For other information on the K40-S build use the  K40-S BUILD INDEX with schematics

Background

For some time I have wanted to:

• Have all the laser systems indicators to be in one place and up on the panel
• Add a Laser tube surface temp sensor
• Have a better looking power pot position meter.
• Try out a sensor mounted on the head to detect a fire

Everything up on the panel

On the panel above:

Upper left: Senses heat at the head and shuts down LPS on overtemp with an alarm

Upper Right: Senses coolant temp and shuts down LPS on overemp with an alarm

Lower Left: Laser temp. Measures temp at the surface of the tube

Lower right: A DVM that measures the voltage on the LPS "IN" pin. 

I got all the sensing meters cut into the upper part of the panel. The Power setting meters bezel had to be hand fabricated. I am satisfied that they are all in one place but I wish I could have all the meters look the same. That's the result of some meters being discontinued and other not having controllers.

Cutting out the panel

The Plan

Nibbling Away

Final Cutout

Sensor Locations

The water sensor is located in the bucket at the end of the output pipe.

The laser jacket sensor is tie wrapped to the laser housing

The cabinet sensor is mounted on the head.

Note I have no idea if this sensor and the controller will respond fast enough to prevent a fire but I figure something is better than nothing at all.

Power Control Meter

More work needed to make this pretty!

Wiring

The meters that require the machine to be shut down have relays wired in series with the laser interlock circuit. These meters have high low setpoins and have audible alarms. 

Parts List

Upper left: Temp Controller

Upper Right: Temp Controller (not available). Use one from above.

Lower Left: Thermometer

Lower right:  DVM

Enjoy & Comment

Don

K40 Exhaust Air Sensor

How do you sense that your exhaust air is working?

My evacuation air system uses a pretty quiet blower and is controlled by a switch on my machine control panel. While working on the machine I noticed the blower was not working but had no way to tell for sure since other than the cabinet its a closed system. Opening the cabinet certainly worked but I wondered how hard it would be to build in a sensor. 

I have to admit this got out of control and one could easily argue that this problem did not need to be solved. But I cannot pass up a challenge to solve a problem that I have not yet solved.

Donate:

Please consider donating (button to the right of this post).
Your donations help fund additional research, tools and parts that I will return to the community as information.

For other information on the K40-S build use the  K40-S BUILD INDEX with schematics

The design

I started the design with the expectation that I could use a micro-switch with a flag on it like is used in furnaces. Turns out that it took much air to activate the switch and also blocked the airway. I also considered using a furnace air pressure switch but was not sure if had enough flow to activate this type switch. I will probably try one of these later although they are expensive.

After tinkering at the bench I decided to use an air vane, magnet and hall effect switch assy. to sense the air. The vane would sit in the air stream and an arm with a magnet activated a hall effect and amplifier that would in turn turn on an led. I powered the hall effect from a 120V to 5V switcher module I found on Amazon. 

Perhaps overkill but now I can tell if my exhaust air is on and it was a fun project. All other approaches were in excess of $100, this one cost me about $10 out of pocket.

The vane is a thin piece of acrylic with a block glued to the top edge. The activator arm runs through that block and is held in position with 2x set screws. The arm simply is inserted through two holes in the blowers body with pieces of plastic tubing keeping it centered during operation. The angle of the arm is adjusted so that when the vane is pushed by the air the magnet departs its position against the hall device. A piece of plastic tubing was pushed over the hall effect sensor to keep the magnet from impacting it when at rest.

I did not CAD the design as it built on-the-fly with parts I had in the bin however the photos and videos that follow I think make the actual build self explanatory.

PARTS

5V supply Note: this little modules are great for getting a small amount of 5V for sensors and such. They need a little attention as the outputs are not set up correctly. See the customer reviews for hints.

Hall Effect sensor assembly

Brackets, actuator vane and actuator were hand made to fit.

Videos

https://photos.app.goo.gl/xsR4mNgfMi9G4oG32

https://photos.app.goo.gl/K8LfRRirnOp5AtDg2

https://photos.app.goo.gl/NE0EdAStAyPm6YaU2

Quick Disconnect

Added a plug-able output because my K40 is now mobile

Enjoy,

Comments and corrections expected

Don

K40 + Light Objects Air Assist

Air Assist 

After trying multiple ways of adding air assist using pipes and such, I decided to just get the LO air assist.

Donate:

Please consider donating (button to the right of this post).

Your donations help fund additional research, tools and parts that I will return to the community as information and how-to's. 

Added the LO air assist

https://www.amazon.com/gp/product/B0094WLPYK/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Your lens may not fit

The stock lens in my K40 did not fit in the LO air assist unit. Its diameter is to small. So I turned an metal adapter ring. Others have used a cut down nylon washer, which I think is a better idea.
I plan to change my lens and diameter later.

Enjoy and comment,
Maker Don