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jonbabbz
12-07-2012, 12:06 AM
Hello, I decided to do a little build log of my machine as I was bored. I also wanted a bit of advice with choosing the correct steppers if anyone would care to enlighten me? I think 3nm would be sufficient but I'd rather be sure.

I'm using sbr16uu rails and the z axis weight is 10.4kg, the whole Gantry weighs 21kg.

I'm currently on with building the steel bed and its just about done, but I've run out of welding rods so I'm a waiting now :(

http://i280.photobucket.com/albums/kk195/techknott/20120709_193536.jpg
http://i280.photobucket.com/albums/kk195/techknott/20120711_182441.jpg
http://i280.photobucket.com/albums/kk195/techknott/20120709_205746-1.jpg
http://i280.photobucket.com/albums/kk195/techknott/20120711_182450.jpg
http://i280.photobucket.com/albums/kk195/techknott/20120711_201141-1.jpg
http://i280.photobucket.com/albums/kk195/techknott/20120711_201130-1.jpg

Robin Hewitt
12-07-2012, 12:34 AM
Very neat and tidy.

3Nm onto a 5mm pitch screw would give you a driving force of 3770N, around 0.38 metric tons. You could rip it apart, I suggest you choose motors for speed rather than power :beer:

audioandy
12-07-2012, 12:43 AM
I agree with Robin, very nice neat build.

Did you do the machining yourself?

Andy

jonbabbz
12-07-2012, 01:15 AM
Thankyou very much. Yes I've done all the machining myself. So are there any recommendations for suitable stepper motors? I would like to be able to get a bit out of it speed wise, but not at the cost of torque. Id like to get it cutting aluminium at some point. Also, I'll be going towards the 80v range for the drivers.

JAZZCNC
12-07-2012, 02:13 AM
Thankyou very much. Yes I've done all the machining myself. So are there any recommendations for suitable stepper motors? I would like to be able to get a bit out of it speed wise, but not at the cost of torque. Id like to get it cutting aluminium at some point. Also, I'll be going towards the 80v range for the drivers.

With 65-70V 3Nm would be my choice and still be plenty fast enough and allow for plenty of extra weight if larger spindle or attachments to Z axis.!!
Gary's SY60STH88-3008B is what I use.

jonbabbz
12-07-2012, 10:02 AM
Thanks Jazz, they were what I was leaning towards but just wanted to be sure.

Lee Roberts
12-07-2012, 12:43 PM
Jon, please see the links below for some reading:

What size stepper motor do I-need. (http://www.mycncuk.com/forums/showthread.php/1524-What-size-stepper-motor-do-I-need)

Nice build so far looks really good, following with intrest.

.Me

jonbabbz
20-07-2012, 11:17 AM
Well I'm some way through welding my bed. Still a bit more to do. Not going too bad to say its the first time I've ever welded. I have all my parts now too, so it should be done soon. If youre wondering why its quite low down. That's the highest I could make it. Its going in an upstairs workshop so I have to get it up the stairs.

http://i280.photobucket.com/albums/kk195/techknott/20120718_153419.jpg

WandrinAndy
20-07-2012, 12:16 PM
Nice build Jon. Also nice to see that the sun was shining out your way!

As someone who has never welded anything and is eventually going to be building a similar base for the X-axis, I have seen mention on another thread that the top bar can be bent by the welding process. Does one approach those welds differently to prevent/reduce warping or distortion?

Andy

jonbabbz
20-07-2012, 12:35 PM
To cut down on any distortion, rather than go all out and nuts with the welding, I clamped everything in place and applied small spot welds to hold it all in place then tried not to let it get too hot for too long while keeping an eye on it with squares and a straight edge. I'm also using steel with a 4mm wall and its going fine. I'm only using an el cheepo arc welder with 2.5mm rods. I tried using 3mm rods at first but couldn't strike an arc without blowing fuses. The day the sun was out is a long gone memory.. ..sigh.

mocha
20-07-2012, 05:31 PM
jon, how much does that base weigh in at? any idea?

jonbabbz
20-07-2012, 06:09 PM
I would guess maybe 50-60kg

m.marino
20-07-2012, 07:24 PM
Really nice looking machine and very well done. Just remember to make sure you can access all your lubrication points. While you don't have to put grease in often, trust me it is no fun when the points are hard to reach. Really nice job, very well done.

Michael

riche543
25-07-2012, 01:42 PM
Nice 1 Jon looks great well done. :)
Riche


Riche.

Sent from my iPhone using Tapatalk

D-man
25-07-2012, 01:59 PM
Hey Jon, nice job!!! Loving that Z also!! Wana knock me one up!!?

rnr107
25-07-2012, 10:52 PM
Hey Jon, nice job!!! Loving that Z also!! Wana knock me one up!!?
Agreed ! Love this Z ! Wonder if I could use same principal to make the table for a milling machine ? Looks rigid enough... :-)

jonbabbz
26-07-2012, 08:22 AM
Thanks guys, here is a little update of the bed.

http://i280.photobucket.com/albums/kk195/techknott/20120721_165652.jpg

D-man
26-07-2012, 08:25 AM
That's very tidy that, nice job! Filling with interest.

The z.... Would you be interested in knocking me one up? This could help towards the build of your machine. I can do everything else but it's always the Z that seems to catch me out when building a machine lol

jonbabbz
26-07-2012, 08:45 AM
Ill be happy to help you out when Ive finished my machine. The problem is i don't have a great deal of spare time at the moment so any i do have, id like to get my machine finished first. Hopefully, that won't be too long. Id be happy to send you the drawings if you need them now.

D-man
26-07-2012, 08:59 AM
Yeah that would be awesome thanks! my email is derekhun@hotmail.com really appreciate that thanks!

could you tell me what size extrusion that is?

jonbabbz
26-07-2012, 09:11 AM
Im at work now so ill send when i get in. Its series 6 heavy extrusion.

D-man
26-07-2012, 09:19 AM
Cheers pal! is that from KJN?

jonbabbz
26-07-2012, 09:25 AM
I got it from a bloke called Phil at Metallin. Nice guy and you can order small quantities and pay with PayPal.

irving2008
26-07-2012, 11:04 AM
I got it from a bloke called Phil at Metallin. Nice guy and you can order small quantities and pay with PayPal.

Had a look at their website. As far as I can see there's no catalogue with mechanical data in it so hard to compare their extrusions with KJNs, also not entirely sure how their fastening works, seems you have to do some drilling? or did you use the corner fastenings with covers, and are they rigid enough (e.g. non-swivel as KJN make a distinction here)?

D-man
27-07-2012, 12:04 AM
Irving if you give me your email I will forward an email from him as I asked him the same question

D-man
27-07-2012, 12:05 AM
Jon did you manage to send those files? Just checking incase my mail is not working. Cheers buddy

irving2008
27-07-2012, 10:30 AM
Irving if you give me your email I will forward an email from him as I asked him the same question


Thanks for the PM... seems the answer is 'no more than whats on the website'. The profile is similar enough I think to the KJN one to use the I values from there, and the E, well I'll assume 6000 series Alloy; should be good enough. Still not clear how the corner fastenings work though.

jonbabbz
28-07-2012, 12:15 AM
Sorry mate, I got tied up last night so ill send it now. All the technical data you can find on the valuframe website, I just ordered from metallin because the order process for valuframe was so damn complicated, lengthy and theres a 100 minimum spend AND they need a business address to ship to....phew!. It's exactly the same stuff though. I did have to do some drilling, I mainly used the standard connectors(m6) and am going to fabricate a few straight brackets. Basically you have to tap the ends of the profile, then slide in the slot connector and drill a 6mm hole through the other side of the connecting profile to tighten it.

jonbabbz
22-08-2012, 08:58 PM
Well, its been a while, but after having so little time to work on my build , I've finally made a bit more progress. I wasn't happy with the height of the bed in the last design. So, i decided to cut it up and make it taller with a bolt together solution so i can get it through doorways. It just seemed like i would be forever on my knees with the other one so here is the new one. Still a fair bit of welding to do but i am at the mercy of the weather atm. Gotta love this country!

http://i280.photobucket.com/albums/kk195/techknott/20120822_192442.jpg

rdpdo
23-08-2012, 12:57 AM
Hi jon

This is a very good job ! I'd like to maje the same thing of you with your rail supporting on aluminium profil for the y ganty !

But i dont understand how you done the job ... Is it pssible to have more pic or explanation on how you have mount the sbr16uu under the aluminium profile ? What kind of fatener do you used for this ? Because it seems very difficult to Screw the sbr16 on the aluminium profile for me... How could you get acces to the head of the screw ? ??

Thanks you very much for your help

Regards

jonbabbz
23-08-2012, 07:27 AM
Drill a hole in the rail, put a bolt in the hole and use a t nut in the rail slot to screw it to.

rdpdo
23-08-2012, 11:07 AM
Hi,

In fact this is - how do you screw the M5 screw in the profil ?? It's seem difficult to do :

http://img145.imageshack.us/img145/6076/sanstitret.jpg (http://imageshack.us/photo/my-images/145/sanstitret.jpg/)

Thanks !!

jonbabbz
23-08-2012, 12:01 PM
If you want to attach it to that size profile, you'll have to use a piece of aluminium plate in between the bearing and profile. Otherwise use a profile twice the width of the one youre trying to use now - with two slots and use button head bolts or washers to slide the bearing into the slots. Then you'll have to drill holes into the profile to access the bolt heads to tighten.

rdpdo
23-08-2012, 07:46 PM
Thanks you jon ;)

jonbabbz
07-09-2012, 10:01 AM
All welding and painting done. Moving onto mounting the y ballscrews now.

http://i280.photobucket.com/albums/kk195/techknott/20120907_081506-1.jpg

jonbabbz
12-09-2012, 12:47 PM
All the ballscrews are on and nicely alligned now. The PSU is wired up and pumping out 72v @ 16amps. Just need to buy a few odds n ends like energy chain, limit switches, e-stop and shielded cable - if anyone has any for sale, im your man. Im also thinking of buying a 2nm stepper fot the z as oppoesed to the large 3nm ones i have as theyre quite heavy and big? Comments and critisisms welcome!


http://i280.photobucket.com/albums/kk195/techknott/20120911_184802.jpg

http://i280.photobucket.com/albums/kk195/techknott/20120911_194856.jpg

JAZZCNC
12-09-2012, 03:21 PM
Im also thinking of buying a 2nm stepper fot the z as oppoesed to the large 3nm ones i have as theyre quite heavy and big? Comments and critisisms welcome!


Not criticism but slight concerns.? @72V on what I think are 75V drives then your very close to Max with not much room for back EMF. Hopefully you'll be ok but if the drives start tripping then chances are that will be the prob.! . . . I wouldn't be running silly high velocity's just to be on the safe side.

The difference between 2Nm or 3Nm weight wise won't make a jot of difference with these drives/voltages running on ball-screws because the mechanical torque ball-screws produce is awesome and really both are more than enough if all your attaching is a router or WC spindle etc. Also with a Z axis you tend not to run high velocity but more acceleration so the available torque is higher has your not so close to the motors corner speed.
Personally I'd use 3Nm for continuity with rest of machine.

Looking good and soon be cutting.?

Tip: cover them sides before you start cutting else all the crap gets onto ballscrews and shoots every where in all directions. Amazing how much sides really help contain the mess.


Edit:
Just spotted that the top box section with rails on is only supported at it's ends. I think you'll find you could suffer from resonance problems at certain depths or feeds esp in harder materials. I Know it certainly will show an effect on finish quality in Aluminium.
Know you've painted it now but I would seriously consider adding some support in the middle, it will pay back in quality of cut believe me.

Edit 2: Eh eh sorry about the add-on's.!! Just spotted that you have the bridge rectifier on a bracket. Really It wants to be on a heat sink, stick it on an old PC CPU heat sink and then fasten that to bracket.

jonbabbz
12-09-2012, 04:17 PM
Not criticism but slight concerns.? @72V on what I think are 75V drives then your very close to Max with not much room for back EMF. Hopefully you'll be ok but if the drives start tripping then chances are that will be the prob.! . . . I wouldn't be running silly high velocity's just to be on the safe side.
The drives are 982's, 80v max so should be ok.


The difference between 2Nm or 3Nm weight wise won't make a jot of difference with these drives/voltages running on ball-screws because the mechanical torque ball-screws produce is awesome and really both are more than enough if all your attaching is a router or WC spindle etc. Also with a Z axis you tend not to run high velocity but more acceleration so the available torque is higher has your not so close to the motors corner speed.
Personally I'd use 3Nm for continuity with rest of machine. Thanks for that, guess ill just use the 3nm ones then.


Looking good and soon be cutting.?
Was hoping within the next couple of weeks, but I damaged (or may have been defective) a linear bearing while assembling it(a couple balls dropped out), so im now waiting for some bearings to arrive.


Tip: cover them sides before you start cutting else all the crap gets onto ballscrews and shoots every where in all directions. Amazing how much sides really help contain the mess.
Thanks, never even thought of that!!



Edit:
Just spotted that the top box section with rails on is only supported at it's ends. I think you'll find you could suffer from resonance problems at certain depths or feeds esp in harder materials. I Know it certainly will show an effect on finish quality in Aluminium.
Know you've painted it now but I would seriously consider adding some support in the middle, it will pay back in quality of cut believe me.
It will be a real pain in the ass to add these now, so I think ill see what its like before I commit to stripping it completely down. Do you think a strut bolted to the underside of the top box section and bolted to the side of the bed would be adequate for this? i could do that while its still up and still have a few bits of box left over from when I cut up the last bed.


Edit 2: Eh eh sorry about the add-on's.!! Just spotted that you have the bridge rectifier on a bracket. Really It wants to be on a heat sink, stick it on an old PC CPU heat sink and then fasten that to bracket.
Dont worry mate, happy for the info. This one was recommended by Jonathan in another thread. Apparently it doesn't require one, (MB256)? I wasn't so sure - especially with the high amount of current that will be running through it. I suppose its better to be safe than sorry. Ill get one added. Cheeeeeeers

Jonathan
12-09-2012, 04:41 PM
Dont worry mate, happy for the info. This one was recommended by Jonathan in another thread. Apparently it doesn't require one, (MB256)? I wasn't so sure - especially with the high amount of current that will be running through it. I suppose its better to be safe than sorry. Ill get one added. Cheeeeeeers

I use the same one and it gets warm, but not hot or anywhere near it's temperature rating so I've not put a heatsink on mine. The peak current running through it is quite high, but here it's the mean current that matters (as that determines the power dissipation) and that is much lower. However if you've got a suitable heatsink lying around then you might as well use it.

Here I'm running one stepper driver with a 3Nm motor at 4.09A from my lab PSU for testing, note the current:

6832

JAZZCNC
12-09-2012, 04:44 PM
Was hoping within the next couple of weeks, but I damaged (or may have been defective) a linear bearing while assembling it(a couple balls dropped out), so im now waiting for some bearings to arrive.

Ye it's a bitch when your balls drop out and before ye know it you have an ASBO. .:joker:

Regards the frame then it's not a big job to do really. Just take 2 diagonal lengths off each leg with brackets at each end that bolt into leg and top rail. . . Simplizz really.
Doing it like this will also allow some adjustment for centre if when testing you find the top rail is slightly bowed.?

Jonathan
12-09-2012, 04:48 PM
Just take 2 diagonal lengths off each leg with brackets at each end that bolt into leg and top rail. . . Simplizz really

I agree ... it's well worth it.

JAZZCNC
12-09-2012, 04:58 PM
I agree ... it's well worth it.

Yep I agree with that has well.!!! . . . Steel box is nice and cheap but if it hits the right resonance it can sing like that annoying twat off Go compare Advert. So anything you can do to help minimise this will show in the finish.

jonbabbz
12-09-2012, 05:06 PM
Thanks for the input. Ill get on the mods then. Jazz, im beginning to think that joke about you getting your balls out in public wasn't really a joke?!? Its not a trenchcoat style regular thing is it?

JAZZCNC
12-09-2012, 05:10 PM
Jazz, im beginning to think that joke about you getting your balls out in public wasn't really a joke?!? Its not a trenchcoat style regular thing is it?

Just depends how many wine gums I've had but ye after half packet anything possible with me. .:very_drunk:

Fivetide
12-09-2012, 07:02 PM
Thanks for the input. Ill get on the mods then. Jazz, im beginning to think that joke about you getting your balls out in public wasn't really a joke?!? Its not a trenchcoat style regular thing is it?

Who hasnt had their balls out in public ? BTW I really like the design.. not that could tell a good one from a bad one , but it feels right to me.. ( No ball jokes plz)

jonbabbz
26-09-2012, 02:13 AM
Progress so far. I've welded some new legs in for support as recommended and am now just waiting for my drag chain chain to arrive. I decided to slave up the y axis and set up mach3 ready. So all went well, i got y moving nice when i noticed that the z axis driver power led was no longer lit. I checked the supply fuse which had blown, so changed it. At which point that also popped straight away, its as though there's a dead short in the driver. Is there anything obvious that i could check inside the driver before i wax another 50 sheets on a new one? I did notice a tiny bit of metal swarf on the pins at the dip switches(pic 3) which i suspect may have done it(whoops a daisy :) Thought it a bit strange that it was going so well! Drivers are 2m982 btw.

http://i280.photobucket.com/albums/kk195/techknott/20120924_212838.jpg
http://i280.photobucket.com/albums/kk195/techknott/20120924_212945.jpg
http://i280.photobucket.com/albums/kk195/techknott/20120925_192825.jpg

jonbabbz
11-10-2012, 12:24 PM
I've had a nice week in the sun doing nothing but think about CNC(sad eh?) So having sorted out a speed issue with kind help from Jazz, I was presented with another problem. Severe vibration on the gantry axis. This was caused by loose bolts holding the rail to the rail support(these were from chai). So having stripped down my gantry completely and trying to tighten the offending bolts, this is what I found:

http://i280.photobucket.com/albums/kk195/techknott/20121008_115535.jpg
http://i280.photobucket.com/albums/kk195/techknott/20121011_111303.jpg

Nearly every bolt had been stripped during assembly in china. So were basically doing nothing. My bad for not checking first. But after having re-tapped the threads and properly putting in new bolts. Everything is hunky-dory again......Phew! Suppose you get what you pay for in this game. I really wish I had dumped a few extra hundred quid and gone for profiled rails though. Maybe Santa will will bring me some along with the new spindle Ive requested from him :welcoming:

Jonathan
11-10-2012, 01:14 PM
I had them work loose on my rails, but didn't see any damage to the screws. Did you threadlock them to make sure they don't vibrate loose again?

jonbabbz
11-10-2012, 01:35 PM
Yep, all glued up and nice and tight. Just waiting for a new driver to arrive from china now, seems to be taking ages. Then hopefully I'll be cutting soon.

Danielroyal25
18-01-2013, 09:57 PM
Hi Jon, new to this site and come across your project. It looks great! Was just after some advice really, been looking at buying an off the shelf solution but after coming across yours I am interested in possibly making one myself.
would you be able to give me a rough time scale and cost of the project (excluding base) and how you went about designing it.
i would be confident in the mechanical side but the electronics and calculations seem a bit daunting.
if you don't want to discuss costs etc over the forum my email is danielroyal25@hotmail.com.
Would really appreciate your advice.
Thanks, Dan

wilfy
18-01-2013, 11:31 PM
i'm glad someone has bumped this, how are you getting on with this fella?

GEOFFREY
19-01-2013, 03:20 PM
Jon, that machine looks fantastic. In the photo it does not look like the bed framework is connected to the new centre legs, if not would the bed be more stiff if it was bolted to those legs?

Once again, congratulations on what looks like a super build. G.

Sodster68
20-01-2013, 10:59 AM
Jon,
Excellent build! An inspiration for my MkII after I finish Wobbly. Keep it up!
Rgrds
Patrik

jonbabbz
23-01-2013, 10:29 PM
Hi Jon, new to this site and come across your project. It looks great! Was just after some advice really, been looking at buying an off the shelf solution but after coming across yours I am interested in possibly making one myself.
would you be able to give me a rough time scale and cost of the project (excluding base) and how you went about designing it.
i would be confident in the mechanical side but the electronics and calculations seem a bit daunting.
if you don't want to discuss costs etc over the forum my email is danielroyal25@hotmail.com.
Would really appreciate your advice.
Thanks, Dan

http://i280.photobucket.com/albums/kk195/techknott/20130123_2059061_zpsae8abbda.jpg
http://i280.photobucket.com/albums/kk195/techknott/20130123_2058561_zps4ed9c68d.jpg
http://i280.photobucket.com/albums/kk195/techknott/20130123_2058491_zps37372159.jpg

Sorry for not posting or replying. I've been dealing with a terminally ill family member so haven't had time for much of anything the last couple months. I actually got the machine finished around the end of November but have yet to cut anything significant on it other than a few signs for work. I started leveling the bed and realized I could really do with a fly cutter as opposed to a quarter inch router bit, and left it at that. I'm totally happy with the speeds and everything though. Hopefully soon i'll have a bit of time to play with it! Think the first thing i'll make will be a touch probe and maybe a belt drive mech for the z axis.

The machine took about 6 months from design to finish and I would estimate a cost of around 1500-2000(cant remember exactly) - all in. It took that long because I was buying bits every month. If you had all the parts ready I'm sure it could be done a lot quicker. I used Rhinoceros(and Rhinocam) to design it. If you're planning a build, the best advice I would give you is to read, read and read some more. Post your designs, get a second opinion and be prepared for constructive criticism and design changes. Also, make sure you're 100% happy with the design BEFORE buying any parts - will save you money in the long run. Good luck.

wilfy
24-01-2013, 12:33 AM
thanks for coming back to post given your recent problems dude.

i took a lot of inspiration for my build of the back of this thread and i thank you for that and again thanks for coming back to update.

what is the spindle you are using and any reason why you choose that over a water cooled one?

jonbabbz
24-01-2013, 10:40 AM
The spindle was simply a router i had lying around. In all honesty its no good for this, it's only 1kw, but will do until I can afford a water cooled one.

jamie aust
06-04-2013, 04:46 AM
Hi Jon, would you be able to send me some size data on your build. Im new to CNC and I do like the way you have done your cnc.
If you could email me jamie.qld AT gmail.com
Can you also post an update on your build, how is it going, what would you change if you did it again.

Regards
jamie

Folc
30-12-2013, 11:21 PM
Anyone from this "theme" still active? ... I'd like to see any sketches or plans ... if it's possible

Folc
07-01-2014, 04:40 PM
realy no one have any information about this machine?

Lee Roberts
07-01-2014, 05:00 PM
realy no one have any information about this machine?

Hi Folc, no i dont think you will find any plans for building this exact machine, however you may find this machine A Sturdy Steel Framed Machine Design (http://www.mycncuk.com/forums/machine-frames-beds/6979-sturdy-steel-framed-machine-design.html) to your liking and this dose come with the information your looking for.

.Me

Folc
07-01-2014, 05:09 PM
tnx for an answer, i already designed my own CNC machine, but before starting building it I would realy want to know the dimensions (height and width) for the bridge and Z axis here ... but tnx for your link too i see much great informations there too

Lee Roberts
07-01-2014, 06:43 PM
Hi Folc, no problem if you need any help or need to ask some questions, please start a new thread and I will keep an eye out for it and help you if i can :beer:.

.Me

Isaac
17-05-2014, 10:55 PM
I know its an old thread, but does this run with 1 ballscrew per axis? How does it run?(if you still read the forums! :))

Clive S
18-05-2014, 12:31 AM
I know its an old thread, but does this run with 1 ballscrew per axis? How does it run?(if you still read the forums! :))

If you look back through the thread it uses 2 screws on X one on Y an the one on Z.

Jonbabbz Nice build by the way it encouraged me to start my build ..Clive

samsagaz
14-04-2016, 06:30 AM
Nice Build! I see that you mount the rails of the z axis in the plate. its better? (sorry for my english)