[daniellyall]

here a chill pill for everyone

[edoctoor]

(wrong) How could that be?

WoodWorking Machines > DIY CNC Router Table Machines > Open Source CNC Machine Designs >
Electronic home switches made easy!

It looks to me that I am in the right place; considering that I am looking for information on DIY open source
Electronic home switches MADE easy and all my inquires are based on the first five pages.

[Al_The_Man]

Wrong Forum?
IMO this thread was in the wrong place to begin with??
Whats the exclusive connection with 'Woodworking Machines' ??
Al.

[edoctoor]

(1) The design to be using the SS441A device; because the experts that use and know how to debug electronics
and read the datasheets know that there is a major difference between a SS441A and clones. I would gladly
take their advice over those that haven't completed a electronics course.

(2) I have this Break-Out-Board

(3) I would like a bright green led to signal at the SS441A device

(4) I would like to contribute to open source

(5) I don't want any usb connectors as I am building a do-it-yourself 36 x 36 cnc that somehow ended up being twice the size as I did not have the heart to cut down the extra long linear rails that I found at Toronto Surplus; secondly, it is my opinion that usb connectors may be ok for homing sensors. But they are not ok in my opinion for limit switches. I would like to keep my homing sensors connections the same as the limit sensor connections.

(6) I would like two leds on my panel (red, green, not bright) to impress the ladies.

(7) I would like to use Romanlini mounts as they are perfect for me and I assume that there is gcode
somewhere as I don't know how to generate gcode from a cad file yet. I will be using MachIII until
I learn the linux version.

(8) I would like at least one capacitor to be used in the design

(9) I will be using 2 wire microphone wire with non-braided shielding

(10) Please, "No marketing" as I want to learn and experience from the team effort of this open source thread.

Can this be done?

[ger21]

Can this be done?

The info in post #39 is really all this thread is about. I don't believe there was any further development, other than Jason's. I don't think that anyone else has built Jason's version. If you want more info on Jason's switches, start reading at post #683.

http://www.cnczone.com/forums/open_s...ml#post1119142

[edoctoor]

The info in post #39 is really all this thread is about. I don't believe there was any further development, other than Jason's. I don't think that anyone else has built Jason's version. If you want more info on Jason's switches, start reading at post #683.

It is like this; if Jason's version is open source? I would like to discuss how it works and remove all the parts of the
circuit that I am not interested in... or better said... tweak it so that it applies to my machine. If Jason's version is
open source my first post applies.

Hi I have read the first five pages about these open source homing switches and I am very interested in the current list of electronics and the schematic. I think my cnc would look great with red and green flashing leds on my sensors and on my panel.

Therefore, I would like an list of electronics and the schematic so that I will have base or starting point to start asking about how it works and be able to pick out the part of the circuit applies to my project, and remove or tweak the parts that don't apply.

If Jason's version is not open source and he chooses take open source information and sell it back to the same thread that developed it... I just don't understand that logic.

Therefore, if Jason's version is not open source. That is great as I can start fresh with the #982 post

(1) The design to be using the SS441A device; because the experts that use and know how to debug electronics and read the datasheets know that there is a major difference between a SS441A and clones. I would gladly take their advice over those that haven't completed a electronics course.

(2) I have this Break-Out-Board

(3) I would like a bright green led to signal at the SS441A device

(4) I would like to contribute to open source

(5) I don't want any usb connectors as I am building a do-it-yourself 36 x 36 cnc that somehow ended up being twice the size as I did not have the heart to cut down the extra long linear rails that I found at Toronto Surplus; secondly, it is my opinion that usb connectors may be ok for homing sensors. But they are not ok in my opinion for limit switches. I would like to keep my homing sensors connections the same as the limit sensor connections.

(6) I would like two leds on my panel (red, green, not bright) to impress the ladies.

(7) I would like to use Romanlini mounts as they are perfect for me and I assume that there is gcode
somewhere as I don't know how to generate gcode from a cad file yet. I will be using MachIII until
I learn the linux version.

(8) I would like at least one capacitor to be used in the design

(9) I will be using 2 wire microphone wire with non-braided shielding

(10) Please, "No marketing" as I want to learn and experience from the team effort of this open source thread.

Can this be done?

Keep in mind that digikey has free shipping if I order over $200.00 and I would like to get a parts list so that
I can order the parts (and the parts for the DIY remote controller box that attaches to the speed control of my
220 volt spindle: it was mentioned in this thread but I am a noob and don't recall what they called that unit)

But once I get the parts, then I can interact with the parts as I ask questions.

That said, again I ask, "I am very interested in the current list of electronics and the schematic."

[Falcon69]

My question to you Jason, is your design open source?

Yes, the schematic is on this forum, just merely look for it. If not, I will work on one. I don't have much time with school and all, but will try.

(1) The design to be using the SS441A device; because the experts that use and know how to debug electronics
and read the datasheets know that there is a major difference between a SS441A and clones. I would gladly
take their advice over those that haven't completed a electronics course.

The SS441A is a superior chip do to it's temperature compensation over it's older competitor, the Allegro A3144E, other than that, no difference. With that said, I've tested both in my bedroom, just recently, and at the time, it was approximately 93 degrees Fahrenheit in my bedroom, yes, i know, hotter than most shops, i do not have AC in my home . Anyway, I really saw no difference in operation. I will be using the SS441A however, because they operate at a less voltage as well.

(2) I have this Break-Out-Board

YNot sure on your board, I'd have to read up on it.

(3) I would like a bright green led to signal at the SS441A device

This isn't a problem, as the switches Roman designed, are designed with an LED or without an LED in mind.Post #39 indicates the wiring to add the LED.

(4) I would like to contribute to open source

Great! That's what this site is for and the group of people here are Extremely helpful.

(5) I don't want any usb connectors as I am building a do-it-yourself 36 x 36 cnc that somehow ended up being twice the size as I did not have the heart to cut down the extra long linear rails that I found at Toronto Surplus; secondly, it is my opinion that usb connectors may be ok for homing sensors. But they are not ok in my opinion for limit switches. I would like to keep my homing sensors connections the same as the limit sensor connections.

That's not a problem, you simply need to just find the connector you want to use for the number of wires coming from the switch going to your BoB. Or, if you do not care to have a quick disconnect (using an added connector), then simply solder the wires directly, use some heatshrink, and call it good. Easy enough.

(6) I would like two leds on my panel (red, green, not bright) to impress the ladies.

This is Possible, as this thread shows. Just do a search for the schematics that John, Myself, and others have drawn up, however, you may have to play with the resistor values to find the brightness you're looking for in the specific LED's you have purchased.

(7) I would like to use Romanlini mounts as they are perfect for me and I assume that there is gcode
somewhere as I don't know how to generate gcode from a cad file yet. I will be using MachIII until
I learn the linux version.

You're in Luck! A few members have made DXF files for that case. I'm sure if you send them a message, they won't have a problem supplying you with the g-code for them. Post #48 and #140. Also, you can check out Post #159, though, I didn't see the file for it, you may need to ask him for it.

(8) I would like at least one capacitor to be used in the design

That's easy enough. The capacitor will help limit noise. It can be done at the switch. Simply place it between the ground and power inputs of the Switch input.

(9) I will be using 2 wire microphone wire with non-braided shielding

This is not possible with Romanlini's design. You will need 3 wires, ground, power, and output of SS441A sensor. You can verify this from post #39. If you are seeking to add LED's to the front of your control panel, then you will need 5 wires total coming/going to each limit switch. I however, would not suggest this type of wire for a CNC. You need wire that can continuously flex. While Microphone cable is actually good cable, for a few nickels more, you can get braided, shielded, stranded, continuous flex type cable that is designed for cable trays and automation machines. And on that note, that type of wire is usually protective against oil, and other contaminates that can damage the outer shell of the cable.

(10) Please, "No marketing" as I want to learn and experience from the team effort of this open source thread.

Note taken, and I apologize.

I hope I haven't hurt anyone feelings... but it would be nice if other ideas could be shared here.

A little, but I'll get over it. You are right, this thread is open source, and should stay that way. I will simply post what I've done, and nothing else, so others my follow the examples, or modify them how they wish.

Jason

[hollisin]

Thanks for everyone's help.

Please see my current version in the attached pictures. The magnet is the little round thing in the white plastic it's 3 mm. There is an empty hole beside it I used a 1/8 inch bit to drill a shallow hole and then I super glued it in. The magnet must be within 3 mm very close for a detection to take place.

This is using a deans connector. I super glued each of the components in their place to hold them temporarily and then I soldered the connectors together. I wanted to take a picture before I filled it up with epoxy.

This is just my first attempt at a detector holder.

One of the things on my particular machine I might end up needing is a detector on the side of the mounting module.

I decided it would be better to fabricate the Detector separate from the mounting plate. What you can do is take a quarter inch or a 16th inch piece of plastic and mounted in a convenient way and then just glued this detector to the Mounting plate.

I got the epoxy in and it's set up. And then I could turn the detector over so I could see through the detector to the magnet. The detector(transistor) is only active when the edge of the magnet moves past the edge of the detector. I tried this in the 90° directions and it doesn't seem to matter so it will not detect the magnet further than the edge of the detector. This is when the detector bracket is resting on the plastic essentially no clearance. About the furthest away I can get it and still get the detector to trigger is about 1/16 of an inch.

[Falcon69]

Good Job, they look good.

Might I suggest wrapping the other end with some heatshrink tubing. You can find some relatively cheap heatshrink on eBay. There's some on there that has a shrink ratio of 3:1 and it is adhesive lined. That stuff works great and will help keep your wires connected to your connectors.

When you pour the resin in, are you planning on coloring it like Romanlini did? If so, what color you going with?

[hollisin]

Thanks for the info about the heat shrink tubing that will be very helpful.

These are some photos of the completed bracket. The round disc has the magnet inside it. I just cut it out with a plug cutter.

I preferred the clear epoxy so that it does not interfere with the color of the LED. I put the deans connector in the photos so you could see what you get when you order one.

The plain block is a spacer that I have cut down by 1/16 of an inch so that it places the detector very close to the magnet When it's mounted on the frame. My plan is to add mounting holes to these pieces and glue the detector to them.

I was going to upload the DFX file and I will if someone wants it. But I started with the original DFX bracket back on posting way back and just modified it over several days until it met my components and my understanding of what I wanted. So I'm not sure how much help that would be to someone else.

The plastic is polycarbonate. It's just what I had in scrap no particular reason. The thicker one is 3/8 inch and the thinner one is one quarter of an inch.

[Evelyn8bli]

It's just what I had in scrap no particular reason.

[RonaldoNZ]

This exchange re the three wire setup.

"(9) I will be using 2 wire microphone wire with non-braided shielding
This is not possible with Romanlini's design. You will need 3 wires, ground, power, and output of SS441A sensor. "

Huh?? why not use the shield as ground, its going to be grounded anyway.

[hollisin]

I will preface what I say with this thought. If you do something and it works, it does not mean its the best approach.

Using a ground wire for signal or power current is really at the top of the "Don't do it" list for best practices. Because it defeats the purpose of having a ground, which is a safety feature. Defeating safety stuff usually does not end well.

I would offer a suggestion on what I am doing. I am using 4 conductor shielded with ground. That way I can use two wires for power +5V and ground. One of the remaining wire can be "home" signal and the other "max travel limit" signal for a single axis. That way, with a little extra work you can cut down on the cable count and group limit connections by axis.
Thanks
Jack

This exchange re the three wire setup.

"(9) I will be using 2 wire microphone wire with non-braided shielding
This is not possible with Romanlini's design. You will need 3 wires, ground, power, and output of SS441A sensor. "

Huh?? why not use the shield as ground, its going to be grounded anyway.

[Al_The_Man]

Using a ground wire for signal or power current is really at the top of the "Don't do it" list for best practices. Because it defeats the purpose of having a ground, which is a safety feature.
Jack

There is the safety aspect, but the other reason for not using the ground as a conductor is that it is OK to ground each end of a shield when the metallic parts of the machine are bonded (equi-potential bonding), but when you start using ground as a circuit conductor it can set up a potential difference between Earth ground points, which is the definition of a 'Ground Loop'.
Al.

[RonaldoNZ]

However each end of the shield would not be connected to ground, we are talking a signal ground here from the bob running to an isolated hall effect module. there is no reason to connect that sheild to the machines ground at the machine end.

Nor is this an earth strap for the purposes of providing a safe ground return. The shield isn't there to provide a safety feature, we are talking ttl levels here, not mains. It's to shield emf from that signal wire.

[Kmb2erl3dn]

I will preface what I say with this thought.

[Al_The_Man]

there is no reason to connect that sheild to the machines ground at the machine end.

Nor is this an earth strap for the purposes of providing a safe ground return. The shield isn't there to provide a safety feature, we are talking ttl levels here, not mains. It's to shield emf from that signal wire.

There has been a shift in thinking in the past few years, it used to be 'mandatory' to only ground one end of the shield, now with with the recommendation of equi-potential bonding it is considered unnecessary.
See Ch6
http://www.automation.siemens.com/do.../emv_r.pdf?p=1
Earth bonding of the machine is just as important for noise prevention as safety.
Especially with the prevalence of TTL (5v) level signals being used outboard of the PC.
There is a post regarding nuisance tripping of limits almost every week here!
These are often cured by the implementation of proper grounding and bonding.
The basic rule still applies, do not use a ground conductor to complete circuit current.
http://www.cnczone.com/forums/phase_...se_issues.html
Al.

[Billie3edick]

It's to shield emf from that signal wire.

[RonaldoNZ]

It's to shield emf from that signal wire.

Indeed, couldn't have put it better

Its really quite simple, 0V should always be tied to ground unless you plan on running the circuit isolated for some reason which is just going to create problems with your circuits 0v floating with respect to ground/earth. This is exactly the problem the "serious noise issue" guy had.

So...since the shield and the 0V rail are in fact already (should be) connected the effect of running a separate 0V conductor inside that 0V shield does nothing other than effectively make some strands of that shield be insulated from the rest for the length of the cable run.

Edit to add: Al thanks for that siemens link, its excellent. Damn board ate my two previous replies, perhaps they where conducted to ground.

[Al_The_Man]

Indeed, couldn't have put it better

:

Gotta be careful quoting these stupid spammers! Bille3 was promptly banned. :devious: (chair).
Al.