I use to take the 5volts from my pc's USB port for my previous cnc and it still works fine this way, at the hands of his new owner.
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I use to take the 5volts from my pc's USB port for my previous cnc and it still works fine this way, at the hands of his new owner.
You don,t say what you want to use the 5V for!! or what psu you have bought. looking at the BOB that will need 5V and 12-24V to run the 5V could be got from the usb. Personally I would have a separate 5V PS.Quote:
Originally Posted by Nr1madman
Haha you my friend are correct :)Quote:
Originally Posted by Clive S
The only thing I got planned for 5v is the Bob and it's signals to the stepper drivers ( pul dir ena )
I've bought a 5V 2A psu and still thinking about using it. If I were to use the pc psu I don't think I would connect usb but get 5v from a Molex harness. That way it's straight from the psu and not through the motherboard. If that makes sense??
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Good to know :)Quote:
Originally Posted by Nickhofen
It seems like a easy option.
I don't know why it's recommended to not use usb to power bobs.. If it's unreliable volt levels or if it's a grounding problem with loops or something?
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That's how I set mine up.Quote:
Originally Posted by Nr1madman
Leaning towards this aproach because pc psus are supposed to be stable!Quote:
Originally Posted by Desertboy
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Small update!
Trial fit of some brackets for energychain.
Still need more paint on them but good fit :D
https://image.ibb.co/gBU35G/20171208_122655.jpg
https://image.ibb.co/fKwGQG/20171208_114215.jpg
https://image.ibb.co/grQMsw/20171208_114207.jpg
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Looks good from here,why do you want to add more color- weigh on them...lol!
Haha thank you!Quote:
Originally Posted by Nickhofen
Im a terrible painter, but I have to try to do better ;)
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I know someone who can help...lol do you know that guy? Most of painting memes and trols on Facebook here has to do with him!
Attachment 23351
No idea who that is.. and I get the feeling I should be glad for it ;)
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More bracket power!
The cablecarrier gets crooked in the end.. but havent fastened all the bolts yet.
Need to shorten some so they dont stick out hehe
https://image.ibb.co/iX1mcw/20171209_203541.jpg
https://image.ibb.co/mHDoqG/20171209_200857.jpg
https://image.ibb.co/mhiA4b/20171209_204118.jpg
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Quick question?
Been making my cablechain brackets from 5mm thick steel angle (had it laying about)
Brackets for proximity swithes..
Ok to use 3mm thick aluminium brackets from unknown ali quality?
Guess they have to be resistent to vibrations?
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3mm will be fine, the switches have no mass really so vibration will not be an issue.
Thanks :)Quote:
Originally Posted by Davek0974
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Not much happening at my end other than a question.
My steppers drives accept both ac and dc.
Is it worth it to do the rectifier and caps to get dc or can I just run ac directly and trust my cheapo drives to have enough capacitans to handle back emf?
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I personally would go down the conventional tried and tested route with a toroidal transformer and rectifier with caps.Quote:
Originally Posted by Nr1madman
Im leaning towards that route...Quote:
Originally Posted by Clive S
There is no way there could be thats big caps in the drives.. so I guess that if I go ac my toroidal transformer will get a beating? Especially since its a 500VA and not overspeced for my application?
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I considered using AC with my my AM882h's but when one of them blew and I replaced it I got an AM882 which is DC only.Quote:
Originally Posted by Nr1madman
I might be wrong here but I think if the drive is rated for AC you wouldn't need caps they're only there to smooth out the DC. That said it wasn't hard I was scared of the PSU build and yes I did blow one up ;) but it really was drill a couple of holes, bolt stuff on and solder 6 wires just double check you wiring and don't plug the wires into the rectifier the wrong way round.
Haha ;)Quote:
Originally Posted by Desertboy
Well Im not scared of the process.. but I got a shitload of smaller caps so alot more than 6 solderpoints :D
Im about halfway through but I cant solder with any kids around.. they just have to touch everything ;)
I figured since the drives provide the motors with dc then some internal conversion must happen in the drives if using ac supply...?
Anyway.. it will look cool if I finish so I guess I will stick to the original plan!
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You must go with DC so I can copy the plans and make my DC power supply!:yahoo:
If I had a drive with the option of AC input, I would go with that. It will have an appropriate internal rectifier/capacitor setup, and actually the capacitors do not need to be that big. You use bigger capacitors when the PSU is feeding multiple drives as you are smoothing with a bigger current demand, and it also provides a bit more isolation between drives so demand from one will not affect the others. Stepper drivers really do not need a very smooth supply voltage anyway - because of the way they work, they are pretty tolerant of supply voltage ripple.
All good points ;)
Nick you have loads of ppl to copy already :D
Neale, you might just have persuaded me ;)
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I know that Robert but I always seek for the latest version,lol!
Hahaha :DQuote:
Originally Posted by Nickhofen
You know to look for the latest stable version... right?
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What drivers have you got?
:hysterical:
Im a cheap bastard (probably on the stupid side)Quote:
Originally Posted by Desertboy
Got myself som 2dm860 chinastyle drivers..
They accept 80vac or 110vdc
Will se how they work ;)
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Whatever works for you I was going to use an arduino and polou drivers originally glad I didn't lol. But they were cheap so I might well use them for laser cutter.Quote:
Originally Posted by Nr1madman
Given the price of a PP BOB the arduino really doesn't make sense and it's actually more expensive assuming you can get a PC for free for this task which I'm sure most of us can.
Just re-read the whole thread and I may have missed it again, but did not see how do you connect the two extrusions to each other? What is their size BTW?
I used 40x80 extrusion, most recommend 45x90 but this size was more availible for me.Quote:
Originally Posted by Zinci
If doing it again I would order 45x90 :)
Connected the profiles with t nuts in one extrusion. Then drilled through the other to be able to screw it together. Thought this would make a nice 90degree angle all by itself but I was misstaken! Have since loosened the bolts and retightened them while checking with a engineers square.. now I have a much better alignment!
Ofcourse the endplates help. Had them milled by a happy forummember with accurate hole placement for easy alignment.
Hope to get some free time soon to continue with the build ;) Christmas period has been hectic!!
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Thanks for taking the time to reply, and thanks for a great build.
Do you have space behind the ball screw, to put a L-bracket instead? Like in this Photoshoped photo?
Attachment 23693
That's not necessary with the construction that is shown as the two profiles will be bolted together as have been mentioned by drilling the top profile in three places and fixing with tee nuts to the bottom profileQuote:
Originally Posted by Zinci
Had to do something today before work :D
What do you guys think about this?
Proximity for home, feelin the rail.
Mechanical switch for limit..
Good?
https://image.ibb.co/g3WSb6/20180131_091438.jpg
https://image.ibb.co/fywFUR/20180131_091500.jpg
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Whaaat! Three places is enough? :DQuote:
Originally Posted by Clive S
Think I did eight..
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You know what, that might work but I think you would need a plate to join the fronts as well.. otherwise it might fold backwards?Quote:
Originally Posted by Zinci
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Micro update!
Got one of my x home switches in place.. just a trialrun for now.. have to paint the steel angle :D
But it works ;)
Tried the z home aswell.. big shock! It also worked haha
And the pics for the curious
https://image.ibb.co/mEjVkc/20180206_194259.jpg
https://image.ibb.co/m2whyx/20180206_194421.jpg
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Nice! Where did you get your proximity switches? Do they work with non-ferrous metal too?
Wallace
Thank you!Quote:
Originally Posted by wallyblackburn
Got them from ebay, 5 for almost nothing :)
Not sure I got the right ones (npn,pnp) but hey.. will go with what I have for now..
Dont think they detect non-ferrous.. can try tomorrow if you want?
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Inductive sensors will detect aluminum but detection distance is roughly 1/2 they use them in 3d printers all the time for auto levelling the print bed.Quote:
Originally Posted by Nr1madman