Old Regular UHU (for 60V to 80V and less)

Hi cnc2,

If you look through the old thread I have posted a picture of my first board. The link is here: /post 593/

http://www.cnczone.com/forums/showth...=14217&page=50

The other 4 boards are somehow different since I have used rectangular wire, something like 4x1mm if I remember correctly, but I do not have pictures of them. It is a problem when trying to solder this big thing on the board and if you get it too hot for too long time the board is going to bend which is not that nice.

It will be interesting to show my boards since they are made like noone has done here on the thread - the FET's are on the other side of the board. It's a problem I don't have my camera here now, maybe will do it with the phone, quality will be poor, but enough to see.

Todor

Quote:

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Originally Posted by LeissKG

Have a look at http://de.wikibooks.org/wiki/Bild:Cu..._(1oz_ext).PNG


This is not a problem at the frequencies used by UHU.


If you find that an trace can not carry the required current at 35 µm thickness, you can solder a wire on the affected trace.

Klaus Leiss

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Thaks a lot Klaus !

Unfortunately i don't read German :(, but the graph says it all and in detail.:)

Thanks !

cnc2.

Quote:

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Originally Posted by LZ1TWB

Hi cnc2,

If you look through the old thread I have posted a picture of my first board. The link is here: /post 593/

http://www.cnczone.com/forums/showth...=14217&page=50

The other 4 boards are somehow different since I have used rectangular wire, something like 4x1mm if I remember correctly, but I do not have pictures of them. It is a problem when trying to solder this big thing on the board and if you get it too hot for too long time the board is going to bend which is not that nice.

It will be interesting to show my boards since they are made like noone has done here on the thread - the FET's are on the other side of the board. It's a problem I don't have my camera here now, maybe will do it with the phone, quality will be poor, but enough to see.

Todor

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Thanks Todor !

Waw that's a monster PCB for a monster motor, did you finish building your machine yet ?

Some pics & vids please !!

What did you put on the copper to protect it from corrosion, i mean in the low voltage side where it isn't tin plated ?

Thanks !
cnc2.

Hi cnc2,

Since I don't have one of those fancy spray stuff that protect the pcb I've done it the old-fashioned way - a cotton tampon with ethyl alcohol which dissolves the resin. This makes a very thin layer of resin all over the board which manages to do the work and helps soldering later. I know there is a better way to do this, but that's how I've done it.

The copper wire was a bit of an overkill, thats why I've used thinner wire on the latest boards.

The machine is still under construction, took more time than we thought in the first place. We are doing the control box in the moment which will house both the computer and the servo controllers. Looks like a small fridge in size. :D

Todor

Quote:

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Originally Posted by LZ1TWB

Hi cnc2,
The other 4 boards are somehow different since I have used rectangular wire, something like 4x1mm if I remember correctly, but I do not have pictures of them. It is a problem when trying to solder this big thing on the board and if you get it too hot for too long time the board is going to bend which is not that nice.

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If you want to add a large cross sectional area try braided wire instead of single strand wire. I have used desoldering braid for such a use, it has a decent cross sectional area and already contains flux. You should clean of the flux afterward.

Klaus Leiss

Quote:

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Originally Posted by LZ1TWB

Hi cnc2,

Since I don't have one of those fancy spray stuff that protect the pcb I've done it the old-fashioned way - a cotton tampon with ethyl alcohol which dissolves the resin. This makes a very thin layer of resin all over the board which manages to do the work and helps soldering later. I know there is a better way to do this, but that's how I've done it.

The copper wire was a bit of an overkill, thats why I've used thinner wire on the latest boards.

The machine is still under construction, took more time than we thought in the first place. We are doing the control box in the moment which will house both the computer and the servo controllers. Looks like a small fridge in size. :D

Todor

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Thanks Todor !

I think i don't understand your solution, what resin are you talking about ? do you mean the photosensitive resin ? in this case i want to tell you that i used toner transfer method on a copper board that has no photosensitive resin on it.

Thumbs up for your machine it's hard to wait to see it running !

Thanks !
cnc2.

Quote:

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Originally Posted by LeissKG

If you want to add a large cross sectional area try braided wire instead of single strand wire. I have used desoldering braid for such a use, it has a decent cross sectional area and already contains flux. You should clean of the flux afterward.

Klaus Leiss

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Thanks Klaus !

Your answer makes me happy because i've thought about using desoldering braid in this manner but wasn't sure it won't bring up frequency or resistance issues, now i'll go with it !

What are you using to clean the flux ?

Some pics or vids of your setup ?

Thanks !
cnc2.

Quote:

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Originally Posted by cnc2

Your answer makes me happy because i've thought about using desoldering braid in this manner but wasn't sure it won't bring up frequency or resistance issues, now i'll go with it !

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You need higher frequencies to get any issues with this. Regarding resistance all that is of consequence is that the resulting resistance should be as low as possible however you achieve that. The only critical point is that you should avoid any points where the resistance is higher than elsewhere in the same circuit. There you can develop local hot spots that can be trouble later. If your braid is not long enough to cover the whole length of the trace you should overlap the shorter sections a bit.

Quote:

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Originally Posted by cnc2

What are you using to clean the flux ?

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Ethananol or commercial flux cleaner if it is necessary. You should look on your solder or desolder braid if a no clean flux is used. If yes no cleaning is needed. If this is not clearly labeled, but instead it is stated that the flux is rosin ( colophony ) you have a no clean flux. You can also use rosin solved in ethanol as a varnish that protects you copper traces from corrosion. If you want to remove excess rosin flux for aesthetically reasons you can also use ethanol

Quote:

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Originally Posted by cnc2

Some pics or vids of your setup ?

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I'm still deciding what I want to build , I'm looking for something that can mill small aluminum parts and can engrave some printed circuit boards.

Klaus Leiss

Thanks for your answer Klaus !

For the desoldering braid i'm using a "Pro's kit 8PK-031B" i found on the net that it has a "no clean flux", thanks for your tips on this one !

Quote:

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Originally Posted by LeissKG

I'm still deciding what I want to build , I'm looking for something that can mill small aluminum parts and can engrave some printed circuit boards.

Klaus Leiss

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Like you, i'm stuck with the same question: what to build ?

I have to choose between a big router (2.40m X 1.40m) or a little mill that can do lots of things, i think i'll go for the little mill to make as much parts as i can for the big router (motor mounts...etc) while i gather the money for the long and expencive ballscrews.

I want this mill to have 4 axes, but i also want the 4th axis to be a lathe, like the one on the vid but with the chuck to be convertible to a lathe by belt and motor change...a mixture of the two mills of the vids...yes i'm a dreamer sometimes !

Thanks !
cnc2.

[ame="http://www.youtube.com/watch?v=Frcg1ZcNGO4"]YouTube - Taig mill 4th axis cut[/ame]
[ame="http://www.youtube.com/watch?v=2Munq_hXxTs&feature=related"]YouTube - Taig CNC mill/lathe[/ame]

Hi cnc2

I was talking about the flux that is used to solder. I am not so sure about all those technical terms, so I may have made a mistake here.

I guess you have to decide what you will use the machine for and then make it to do the job. My work here is dedicated mainly to wood and other soft materials, that's why I look for longer axis travels. Metal working is not possible with it, anyway.

Todor

Quote:

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Originally Posted by LZ1TWB

Hi cnc2

I was talking about the flux that is used to solder. I am not so sure about all those technical terms, so I may have made a mistake here.

I guess you have to decide what you will use the machine for and then make it to do the job. My work here is dedicated mainly to wood and other soft materials, that's why I look for longer axis travels. Metal working is not possible with it, anyway.

Todor

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Hi Todor,

No problem bro ! no one is taking an exam here :)
Did you test run your controller ? becausei've read that flux should be cleaned
from a circuit.

Me too, i want to build a large router (to make kitchens...etc) but need to make the metal parts for it, in here metal shops charge you for "what you look like" so, there's no fix price.

Thanks !
cnc2.

cnc2 - so just dress like what will fetch you the max discount :D

for cabinet making wood router may be you can look at www.mechmate.com

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Originally Posted by contactirfu

cnc2 - so just dress like what will fetch you the max discount :D

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In this case you'll have more chance to be tagged "hippy" and have your questions ignored :confused: Today i saw a metal shop that i didn't know & tried to ask them for a price list or the price of an hour of work nothing then i asked for the price of making a timing pulley they said give us a schematic, on what basis do you charge for pulleys ...nothing not even an approx price :confused:

Quote:

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for cabinet making wood router may be you can look at www.mechmate.com

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Thanks for the link Irfan !

Did you build yours following these plans ?
Where did you get the ballscrews from ? (and if possible:for what price ?)

Thanks !
cnc2.

I finally did it!
I managed to blow up 2 uhu's!
But let me first tell you what happened.
These are 4 uhu boards that I got from Manjeet.
After I solder them I picked one up and tested itas I read.
Everything went o.k. so confident for
my soldering, I connected another 2 to make a
complete test as a 3axis system without testing
them one by one.
But unfortunately the other two didn't moved.
The shaft was free to move it with my hand and
if I turn it too much the led was lit.
Then I tried to test them one by one and as soon as
I gave them power the two ir2184 were blown.
I don't know what went wrong and to tell the truth
I was pretty panicked. After I blew and the second
one I stopped saving the last one for testing it the next
day as it was pretty late and I was pretty confused.
The next day with my head clear I wired the last one
and thankfully it didn't blew. But it didn't worked either.
As I said when I give it power the shaft it doesn't hold
it's position and when I turn it with my hand it turns freely
and if I turn it too much the position error led lights up
properly. And the dos program does communicate with the
controller properly.
So my question is: how do I debug it?
I'm totally in the dark here and any help would be really
appreciated.

its really difficult to tell - did you follow the procedures to assemble the old type board,
chk resistor values etc.,

I have 3 kits from Manjeet which worked easily first time.

whats exactly blown : chk the old thread there is lot of data about these old drives there. :)

So after 6 months of silence the old thread is given a life. :)

Koslaz, I guess there is something wrong with the output stage. Can you tell me what are the power FETs and the voltage you are using. On the "blown 2" board I see the upper right CAP on the logic rail has its cap bumped, or it just looks like that.

It is surely a mistake somewhere, a component put backwards, smth like that.
Try to power it with a lower voltage, I always use 12V with a power resistor in series to check if the boards are OK and functional. I never afforded to switch it first time with the proper working voltage.

Check for interconnections between the traces on the board. Some of them are quite thin and close. I've made 2-3 of these on the logic side, glad it didn't let to smoke, it just did not work.

And one other thing - you should always test them one by one firstly.

Todor

Hi.
I have finally assembled my old uhu board wich i had routed out from a blank pcb board.
I have failed to connect to the terminal, i have tried different computers and terminal program without any success. And yes, it is a strait cable.
When i tested some points on the board i saw that there is no -12V from TL082CP on pin 4 but i have +5V into pin 8 and i can adjust the voltage to pin 2 & 6 between 0 - 1.13V with R12 but there is no change to the led D21,it is just 3,8V.
Is this critical for the MAX232 so it doesnt work without the -12V ?
Is my TL082 broken ?
Sorry for my English
Per

Quote:

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Originally Posted by per.e

Hi.
I have finally assembled my old uhu board wich i had routed out from a blank pcb board.
I have failed to connect to the terminal, i have tried different computers and terminal program without any success. And yes, it is a strait cable.
When i tested some points on the board i saw that there is no -12V from TL082CP on pin 4 but i have +5V into pin 8 and i can adjust the voltage to pin 2 & 6 between 0 - 1.13V with R12 but there is no change to the led D21,it is just 3,8V.
Is this critical for the MAX232 so it doesnt work without the -12V ?
Is my TL082 broken ?
Sorry for my English
Per

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I have tested PCB with only +5V and GND and communication with PC works (of course, whole controller not, since there is no +12V). I must added -12V because I can't find any connector for it on original PCB.

Quote:

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Originally Posted by per.e

Hi.
I have finally assembled my old uhu board wich i had routed out from a blank pcb board.
I have failed to connect to the terminal, i have tried different computers and terminal program without any success. And yes, it is a strait cable.
When i tested some points on the board i saw that there is no -12V from TL082CP on pin 4 but i have +5V into pin 8 and i can adjust the voltage to pin 2 & 6 between 0 - 1.13V with R12 but there is no change to the led D21,it is just 3,8V.
Is this critical for the MAX232 so it doesnt work without the -12V ?
Is my TL082 broken ?
Sorry for my English
Per

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The -12V is generated on the Max232 internal charge pump circuit. It will never be -12V exactly but anything above -5Volts will work. Check that you have the specified Max232 chip (including suffix letters), they require different capacitor values depending on the suffix letter..

By the way, without a negative voltage present you wont get reliable RS232 communication either.

Thanks for your reply kreutz.
It is MAX232CPE chips with 10u caps around it.
I will change the caps (10u-0.1u) to se if that was the problem for me.
Best regards:
Per