[kdoney]

What type of bit do you use? What is the feed and speed and how thick is this granite? I would like to try that myself.

[balsaman]

He is cutting graphite, not granite.

Eric

[agilityrun]

I'd be real interested in how you're cutting the graphite , your max depth of cut and how small a cutter you can use. I've been looking at an alternative at work for cutting graphite electrodes. Currently using a do all saw modified to cnc.

[Mr.Ed]

Balsaman,

I've read your thread a couple of times now and must say it's a real eye-opener.

I'm looking to buy some Linear slides like yours. First started out on ebay in the Netherlands, but if you do a search on THK there are no entries found. As i stated somewhere before, ebay in the NL is a real joke.

Anyway, at ebay on the other side of the big pond, i find "lots" of THK linear slides, in all sizes and types. If i import a set of those i better get the right ones in one try! First, if i buy them for let's say 20 dollars, they will add like 20 dollars or so for shipment. So things i buy in such a pricerange are double more expensive for me then for you guys.

Could you (would you ) please shed some light on the type and size of slides you found in the dumpster, and using now? Did you find any print on those bearing blocks?

Secondly, what do you think, is the total length / amount of 8020 extrusion that you used?

I'm overall impressed by your project sofar, and the whole community here on cnczone. Great job.

Mr.Ed

[kong]

Balsaman, just reading through your err/res manager post, and I have a couple questions for you (no surprise there then!). I understand the basics of how it works, but under the 1k ohm resistor for the LED, there is another symbol that looks like another led, what is this please. Also, the way I see it, you are using normally open switches for your limits, I have a preference for NC, so how coiuld I modify the circuit to use these instead? I figure on using a seperate 5v supply, where you have indicated enc+, and also using a momentary switch instead of relays, I take it this will be ok? These may sound like daft questions, but don't want to blow anything up!

[Mr.Ed]

I'm first !

I think Balsaman has a lot on his mind right now. I think he underestimated the amount of response on his thread just a little bit !

Ed.

[balsaman]

Hi guys, sorry was away for a few days. I will answer your questions tonight when I have some more time.

Eric

[balsaman]

Originally posted by Mr.Ed
Balsaman,

I've read your thread a couple of times now and must say it's a real eye-opener.

I'm looking to buy some Linear slides like yours. First started out on ebay in the Netherlands, but if you do a search on THK there are no entries found. As i stated somewhere before, ebay in the NL is a real joke.

Anyway, at ebay on the other side of the big pond, i find "lots" of THK linear slides, in all sizes and types. If i import a set of those i better get the right ones in one try! First, if i buy them for let's say 20 dollars, they will add like 20 dollars or so for shipment. So things i buy in such a pricerange are double more expensive for me then for you guys.

Could you (would you ) please shed some light on the type and size of slides you found in the dumpster, and using now? Did you find any print on those bearing blocks?

Secondly, what do you think, is the total length / amount of 8020 extrusion that you used?

I'm overall impressed by your project sofar, and the whole community here on cnczone. Great job.

Mr.Ed

My bearing blocks say THK HSR20 on them, so I assume that means they fit on 20 mm rail.

I used about 36 feet of 8020 extrusion not including the table it sits on. Basically 4-48" and 4-30" parts for the base, and 4-30" parts for the trolley.

Eric

[balsaman]

Originally posted by kong
Balsaman, just reading through your err/res manager post, and I have a couple questions for you (no surprise there then!). I understand the basics of how it works, but under the 1k ohm resistor for the LED, there is another symbol that looks like another led, what is this please. Also, the way I see it, you are using normally open switches for your limits, I have a preference for NC, so how coiuld I modify the circuit to use these instead? I figure on using a seperate 5v supply, where you have indicated enc+, and also using a momentary switch instead of relays, I take it this will be ok? These may sound like daft questions, but don't want to blow anything up!

The drawing on the bottom of this page is the working ERR/res manager that I am currently using.

Under and to the right of the 1 k resistor is a diode. This is to prevent the happy drives LED's from turning off when an unhappy drive faults.

I am using NC limit switches.

Basically, if the base of the transistor is getting 5 volts (from a drive pin 5 or the O.T. switches, the transistor is on and the collector is at 0V. When this is true the LED is on and we are happy. if a drive faults, or a O.T. switch opens, the base goes to 0V, and the transistor turns off. The collector goes to +5V and the LED for that drive (or the O.T circuit) turns off. The happy drives LED's stay on because the diodes. Once any of the transistors collectors go to +5, the last transistor turns on and it's collector goes to 0V, whick tells the 'puter something bad has happened.

Eric

[balsaman]

Kong,

You NEED to use the enc+ for the +5 volts (at least according to mariss of geckodrive).

I am still quietly working on my 4th axis. I added the 4th drive, top right hand corner. Almost like I planned it to fit there (I didn't).

[balsaman]

My good tool and die maker buddy Chris made me an adapter for my 4 jaw chuck so it will fit my gearbox. Here it is holding a jar of putty! I will be turning a round chunk of wood tomorrow sometime! (I hope)

Eric

[kong]

Thanks very much Balsaman, I understand it now. I found a nice e-stop circuit posted by Mariss too, over on the cad_cam_edm_dro groups. I'm not the most electronically minded of people, so hope I don't screw-up!
You'll to get hold of a video camera now and get some film of the fourth axis in action

[turkgeltz]

Your cutting graphite interests me. I am curious on how thick it is and what you use to cut it with. Do you use real small carbide cutters?

[kong]

Firstly, an appology. I have been reading the cad_cam yahoo group, and noticed a few posts about using an external 5v to reset the drives. I know it is contrary to what you have said, but I posted on their asking for confirmation, hope you don't take offence
Now, more stupid questions. If I end up using the enc+ to reset the drives, are you using each enc+ to reset each drive, or when you press the reset button, does a single enc+ reset all the drives at once? Secondly, due to my lack of electronics knowledge, I was thinking of adding diodes in place of the relays on your circuit, then to the momentary reset switch, but I can't quite work out if this will keep each circuit isolated, or will it be the equivalent of daisy-chaining the err/res terminals together, therefore rendering your circuit useless. Your advice would be appreciated, Jason.

[balsaman]

No offence taken.

I have found the whole err/res thing very elusive myself. I emailed Mariss some of the questions you are asking. Marriss told me it needs to be the 5 v from the enc+. Why? I don't know. I also asked if I can use just one enc+ to reset all the drives and got no answer. Because I hate the smoke, i decided to play it safe, thus the relay.
I suppose the diodes would work, if you are using the enc+ from one drive to reset all the drives. Let me know what you find out at CAD CAM...

Eric

[kong]

Well, the reply I got was concerning connecting all the drives err/res together to reset them all at once, and it seems this may create a lot of interference causing one or more of the drives to shut down. No reply on the external power supply yet though. I think I will play it safe, and do as you have done. Relays, and use the enc+ to reset it's own drive. Thanks for the help, I'm looking to get some piccies up in the next couple of weeks

[HomeCNC]

I have always used one enc+ to reset all the drives and I have never had any problems at all.

[kong]

Darn it, I thought I had enough spare switches to go individually, but I don't. So, HomeCNC, to confirm, I can go from one enc+ terminal to a push switch, then from the switch I can go straight to each err/res terminal? As long as there are no other components needed to prevent smoke, I will wire it in this afternoon. Thanks for the help guys!

[HomeCNC]

Kong,

Go to my web site and look for the servo controller box wiring drawing. Look at how my two position switch turns on/off the Gecko's.

[kong]

Thanks HomeCNC, it is done now. I realised that if I wire the err/res terms together to one enc+ it would render Balsmans cicuit useless so I got hold of some more switches, and now have each err/res to it's own enc+.