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totts
25-06-2014, 09:44 PM
Hello everyone, well after making my first router type cnc machine on a budget ive decided to push the boat out and make a milling machine based of a sieg x3 machine.

The machine is going to be a bit larger than an x3 and hopefully far more rigid.

linear rails on all axis
DQ860MA 80V Drivers
yet to decide on powersupply
3.0Nm on X and Y nema 23
4.5Nm on z nema 34
2.2kw spindle to start with and hopefully BT30 spindle with ATC in the future.

Pictures to follow:

totts
25-06-2014, 09:49 PM
Hopefully this is what it will look like: Nearly fully Drawnhttp://img.tapatalk.com/d/14/06/26/zu7yde6y.jpg


Ears welded up to support the z axis
http://img.tapatalk.com/d/14/06/26/epy4u4a9.jpg


Z axis sides, 20mm thick:
http://img.tapatalk.com/d/14/06/26/husu9y2u.jpg


The z axis fully built ready to be surface ground:
http://img.tapatalk.com/d/14/06/26/nyzamede.jpg



Surface ground and holes drilled and tapped for the ears:
http://img.tapatalk.com/d/14/06/26/beneme2u.jpg


Just checking the squareness: looks pretty good although this is adjustable on final assembly:
http://img.tapatalk.com/d/14/06/26/6eza8are.jpg



Mock up:
http://img.tapatalk.com/d/14/06/26/8e6u8e7y.jpg



Steps machined for linear rails and ball screw supports and nut:
http://img.tapatalk.com/d/14/06/26/ryma9ezy.jpg



All holes drilled for linear rails, ball screw supports and the screws which will push them towards the parallel edges:
http://img.tapatalk.com/d/14/06/26/une7ehad.jpg



Y axis plate machined and holes drilled ready to mount the rails and then surface ground:
http://img.tapatalk.com/d/14/06/26/umu2e8y5.jpg

totts
25-06-2014, 09:51 PM
This is just a test piece to check how well the taper locks up: was pretty good with just letting it drop in under its own weight, it would stay in when held upside down, and with a tap of a mallet i wasn't able to pull it apart by hand :)


http://img.tapatalk.com/d/14/06/26/hu9ubehu.jpg

http://img.tapatalk.com/d/14/06/26/aradupa3.jpg


Adjustable gas strut to help with the weight of the heavy z axis:

http://img.tapatalk.com/d/14/06/26/y4a8ege3.jpg


That's all for now apart from the rails and ball screws that everyone has seen before, material for the bed has been ordered and hopefully will be starting this soon :)

Hopefully everyone likes the build so far!

Washout
25-06-2014, 10:10 PM
Very nice and definitely will be following this build.

Lee Roberts
25-06-2014, 11:41 PM
There I was at lunch time today browsing through google images at other peoples mill type builds (shortly after reading through JBs x3 conversion thread), i'm keen to have a go at my own mill type, is it obvious yet?

Then I jump on tonight and I find this gem of a thread! Yea! Perfect timing, cant wait for the rest totts !?!

.Me

GEOFFREY
26-06-2014, 12:23 AM
Starting to look very purposeful. Well done. G.

totts
26-06-2014, 01:36 PM
Thankyou, lots still to do, everytime i think about it theres more to do! :(

Lee Roberts
26-06-2014, 01:52 PM
Thankyou, lots still to do, everytime i think about it theres more to do! :(

Hehe always the way, are you going to fill the z axis column with anything to help with resonance or do you plan for something else, what are you going to use for the base of the machine, my thoughts are a nice slab of steel?

.Me

totts
26-06-2014, 01:59 PM
I have a nice solid slab of aluminium as shown in the drawing, about 500mm x700mm by 76mm thick so i hope this will be solid enough.

I was going to fit some of the electronics into the colomn but i am now going to make a stand to house the spindle cooler, electronics, pc and coolant pump, so will probably think about filling the column with something after the z stepper and y stepper is mounted so i know where to fill.

Trouble is the cost keeps mounting up :( best not to take note and hide the reciepts from the missus hahah

Jonathan
26-06-2014, 02:11 PM
Good start - almost getting jealous!

A few general observations...

Have you seen the BT30 ATC spindles on Aliexpress? If you're happy with 6000rpm then they're not excessively expensive:
http://www.aliexpress.com/wholesale?SearchText=bt30+spindle&catId=0&initiative_id=

PSU - why no decision? A toroidal transformer of around 500VA would be ideal.

What is the mass of the Z-axis (head, spindle etc) and what are the dimensions of the Z-axis ballscrew? I've made a script to calculate it more accurately, so if you post that information we can make sure the motor you've chosen is the best option. I suspect you may be OK with one of the 3-4Nm Nema 24 motors. The gas strut makes surprisingly little difference if you try to get a reasonable acceleration...

Correct me if I'm wrong, but it looks like you're leaving the back of the Z column open, so it's a C-shape section not a box? If so then you should defiantly put another plate on the back, as the torsional stiffness of a C-section is very low compared to a box. That's one of the big advantages of putting the ballscrew on the front of the column, not inside - you can have a closed section.

Lee Roberts
26-06-2014, 02:42 PM
Good start - almost getting jealous!

Correct me if I'm wrong, but it looks like you're leaving the back of the Z column open, so it's a C-shape section not a box? If so then you should defiantly put another plate on the back, as the torsional stiffness of a C-section is very low compared to a box. That's one of the big advantages of putting the ballscrew on the front of the column, not inside - you can have a closed section.

Dito!, Jonathan if he was to close the back up and opt for a box, would it be of worth while benefit to also add some ribs inside the box, I was thinking towards cantilever, an X in a square, the through sections on each plate would also allow then for the filling of the column?


I have a nice solid slab of aluminium as shown in the drawing, about 500mm x700mm by 76mm thick so i hope this will be solid enough.

I was going to fit some of the electronics into the colomn but i am now going to make a stand to house the spindle cooler, electronics, pc and coolant pump, so will probably think about filling the column with something after the z stepper and y stepper is mounted so i know where to fill.

Trouble is the cost keeps mounting up :( best not to take note and hide the reciepts from the missus hahah

Sounds like it would be.

I think its fair to say that making it a box and filling it would be of more benefit to the machine.

Hehe, what's new :encouragement:.

.Me

totts
26-06-2014, 02:57 PM
Hmmm yeh true i will add a back the column now, but im not sure on the ribs as if i weld these it may upset my ground face, i may add a couple bars inside to act like rebar. I will get some info on the z axis as im not sure weather to make them out of steel or ally for acceleration.
Ballscrews are 1605 on all axis.

Toroidal transformer is the way i am going for now, just need to do some research.

totts
26-06-2014, 11:57 PM
A bit more work done tonight, the beginning of the bed. This is the main body where steel strips will sit creating the t slots, coolant channels on either side. This will eventually be ground.

http://img.tapatalk.com/d/14/06/27/y7e2y6yg.jpg

Jonathan
27-06-2014, 05:51 PM
Hmmm yeh true i will add a back the column now, but im not sure on the ribs as if i weld these it may upset my ground face, i may add a couple bars inside to act like rebar.

I don't think adding more than the plate to the back of the column will make much difference, as it's the least stiff parts of the machine you need to target if trying to make it stronger. Intuitively I'd say that's a different part, but hard to say without modelling it, which takes a long time...


I will get some info on the z axis as im not sure weather to make them out of steel or ally for acceleration.

Yes please do. The difference in torque required from using aluminium vs steel is unlikely to be significant, plus steel has better damping properties (http://www.atlasfdry.com/grayiron-damping.htm) so I'd prefer steel. Although as Lee has pointed out, there are other ways to solve the damping problem.

totts
27-06-2014, 06:04 PM
I don't think adding more than the plate to the back of the column will make much difference, as it's the least stiff parts of the machine you need to target if trying to make it stronger. Intuitively I'd say that's a different part, but hard to say without modelling it, which takes a long time...


Not quite sure what you mean there? Would it be a good idea to add a plate to the back of the column and fill it with resin, or concrete?


Steel it is then! Cheaper too! Does anyone know the realistic weight of a 2.2kw spindle?

I will hopefully be goin to have a bt30 cartridge and motor, but i suppose it wont be too difficult to change the stepper motor of needed in the future.

Lee Roberts
27-06-2014, 07:48 PM
Not quite sure what you mean there? Would it be a good idea to add a plate to the back of the column and fill it with resin, or concrete?

Steel it is then! Cheaper too! Does anyone know the realistic weight of a 2.2kw spindle?

I will hopefully be goin to have a bt30 cartridge and motor, but i suppose it wont be too difficult to change the stepper motor of needed in the future.

He’s talking in terms of adding strength to the machine and he’s right but I was really referring to eliminating resonance more than anything, I can’t see that adding ribs/reinforcing plates wouldn’t add extra strength to the column, I think they would help towards stopping any twist in the column at the very least.

I think the problem with concrete is that it’s relatively brittle (though I note your suggestion of using rebar), cracks could form in the concrete and over time it may break down inside the column, I don’t know enough but I’m guessing that it doesn’t really have the same dampening properties as other materials, epoxy resin is a favourite but so is kiln dried sand and the sand is cheaper in comparison.

I think what I will do with mine is to, reinforce the column on the inside, use a mix of aggregate (different sizes, type 2, pea shingle and so on) to then fill the column, then backfill the lot with epoxy resin (filling up the leftover voids) all the way to the top, hopefully creating one solid mass. The idea being the aggregate is just away to use less resin (cost vs. cost) but also brings back the properties of using sand.

.Me

totts
27-06-2014, 10:13 PM
Right okay i see now, i think the plan will be to enclose the section in the back which isnt being used by the stepper motors, and fill it with sand, i can always use a resin afterwards if i change my mind.

Lee Roberts
27-06-2014, 10:23 PM
Right okay i see now, i think the plan will be to enclose the section in the back which isnt being used by the stepper motors, and fill it with sand, i can always use a resin afterwards if i change my mind.
Exactly, you could run some tests to see the difference with and without sand, you may not even need any.

.Me

totts
27-06-2014, 10:26 PM
Back to work with my column to drill more holes haha. The bloody thing is heavy hahah!

totts
30-06-2014, 10:29 PM
What is the mass of the Z-axis (head, spindle etc) and what are the dimensions of the Z-axis ballscrew? I've made a script to calculate it more accurately, so if you post that information we can make sure the motor you've chosen is the best option. I suspect you may be OK with one of the 3-4Nm Nema 24 motors. The gas strut makes surprisingly little difference if you try to get a reasonable acceleration...





Okay after managing to get on the computer i have made sure my plates are made of steel, and from what i can find the 2.2kw spindle is around 5.15kgs then the z axis is around 45kgs.

deisel
30-06-2014, 11:05 PM
its an impressive build so far totts,wheres the adjustable gas strut from and whats it rated at?thanks

totts
30-06-2014, 11:10 PM
http://www.strutsdirect.co.uk/product_info.php/variable-force-gas-strut-sd03-400-p-76

Their postage is a little high but not to badly priced.

They come in many lengths n sizes, mines adjustable set at 1200N but will release the pressure when everything is assembled.

deisel
30-06-2014, 11:32 PM
not bad at all,thanks a lot,
keen to see this mill in action.,i did toy with making my own for a while then bottled it and bought an sx3.

totts
30-06-2014, 11:43 PM
Yeah i came very close to getting an sx3, axminster had a 10% off all machines, and when i went on the website they had been reduced due to discontinuing them, and could have picked a new one up for £800!

Only thing that stopped me is the need for a slightly bigger travel and higher spindle speeds.

Have you a video of your sx3 in action?

deisel
30-06-2014, 11:55 PM
Have you a video of your sx3 in action?
no not yet I bought it new from arc a while back and immediately ripped it aprt and fitted ball screws and steppers.(wishing I put profile rail on it after seeing what you and jonathan are upto..upgrade for the future maybe)at the minute im on the wiring so a week or two away yet.

totts
30-06-2014, 11:58 PM
Will be very interested to see it running! Yeah profile rail is bloody exspensive tho :(

totts
02-07-2014, 07:26 PM
Got some steel strips made up now ready to be bolted onto the bed, just waiting for some stainless steel countersunk screws to turn up!

http://img.tapatalk.com/d/14/07/03/anugazyd.jpg

charlieuk
02-07-2014, 08:10 PM
I would be very carfull filling anything like that with that much epoxy and when it cures it can produce a huge amount of heat and contained in a metal tube you could have a small disaster on your hands. If you do want to do this make sure it is extremely slow curing and if anything put some bags of ice around it to keep the heat down and only do a little at a time.



Heís talking in terms of adding strength to the machine and heís right but I was really referring to eliminating resonance more than anything, I canít see that adding ribs/reinforcing plates wouldnít add extra strength to the column, I think they would help towards stopping any twist in the column at the very least.

I think the problem with concrete is that itís relatively brittle (though I note your suggestion of using rebar), cracks could form in the concrete and over time it may break down inside the column, I donít know enough but Iím guessing that it doesnít really have the same dampening properties as other materials, epoxy resin is a favourite but so is kiln dried sand and the sand is cheaper in comparison.

I think what I will do with mine is to, reinforce the column on the inside, use a mix of aggregate (different sizes, type 2, pea shingle and so on) to then fill the column, then backfill the lot with epoxy resin (filling up the leftover voids) all the way to the top, hopefully creating one solid mass. The idea being the aggregate is just away to use less resin (cost vs. cost) but also brings back the properties of using sand.

.Me

Lee Roberts
02-07-2014, 11:57 PM
I would be very carfull filling anything like that with that much epoxy and when it cures it can produce a huge amount of heat and contained in a metal tube you could have a small disaster on your hands. If you do want to do this make sure it is extremely slow curing and if anything put some bags of ice around it to keep the heat down and only do a little at a time.

Thanks for the heads up Charlie, is it really that bad?

.Me

charlieuk
03-07-2014, 12:27 AM
Thanks for the heads up Charlie, is it really that bad?

.Me

depends exactly on the epoxy but yes especially in warm temps, if you left a cup of epoxy to cure on its own you would be surprised how much smoke it can make! its a exothermic reaction so when if heat starts to build its a chain reaction and just gets hotter and hotter and will quickly turn into a smoking and bubbling mess. Ive never had flames but have heard of it. It all so doesn't make any different if you have some sort of filler mixed in with the epoxy so less actual resin to fill the space it will still have the same effect. As i said small quantities a bit at a time in a cold temp is your safest bet.

totts
03-07-2014, 12:40 AM
Blimey i knew it could get warm but not that hot! I think ill start with the sand!

totts
04-07-2014, 11:09 PM
Had a talk today about dampening and have thought of shot blast(cast iron type) mixed with kiln dried sand?


Also a bit more progress....

http://img.tapatalk.com/d/14/07/05/2ygade7a.jpg

Ground and Ready to machine the slots on the top, and the steps on the underside of the bed.

Once the rails have been bolted to the bottom it will be ground again to ensure the top is parrallel to the rails.

deisel
03-08-2014, 10:14 AM
Any progress totts?

totts
03-08-2014, 11:20 AM
A few things, just been busy at work :( done a few parts but not interesting tho, just added a plate to the back of the z axis and made a few home switch mounts, got a few bits of aluminium and steel box section delivered, so hopefully will be able to start the stand, and start building :). Oh and have managed to start painting a few bits!

Ger21
03-08-2014, 01:47 PM
depends exactly on the epoxy but yes especially in warm temps, if you left a cup of epoxy to cure on its own you would be surprised how much smoke it can make! its a exothermic reaction so when if heat starts to build its a chain reaction and just gets hotter and hotter and will quickly turn into a smoking and bubbling mess. Ive never had flames but have heard of it. It all so doesn't make any different if you have some sort of filler mixed in with the epoxy so less actual resin to fill the space it will still have the same effect. As i said small quantities a bit at a time in a cold temp is your safest bet.

You don't want to fill it with just epoxy, as that won't dampen anything. You want an epoxy-sand mix, with ~10-15% epoxy. You need a thin, slow setting epoxy to get enough working time. The sand will keep it from getting hot.

I've mixed up a cup of epoxy sand, and it doesn't get hot at all. A cup of plain epoxy, on the other hand, will exotherm and get very hot in only a few minutes.

totts
19-08-2014, 09:18 PM
Few more things finally done after holidays, and a very busy couple of months at work!

Have designed and made the steek stand for the machine

http://tapatalk.imageshack.com/v2/14/08/19/c58097494b4ef8e89b0321fa260e70ee.jpg

Have roped in my dad to make the electronics cabinet!!

Steel frame has been welded up and will hopefully have a lick of paint this weekend!

Have also managed to make one of two plates which connects the x and y axis together...


http://tapatalk.imageshack.com/v2/14/08/19/6e0060a386138a7cd2225718abf89b32.jpg


Hopefully will be able to make the other tomorrow,

Soon be able to start putting things together :)

irving2008
21-08-2014, 06:54 AM
Stand needs some diagonal bracing or will flex/resonate under load. Ideally the electronics box should be steel not wood to provide safety earth and interference reduction.

totts
21-08-2014, 07:14 AM
The stand is merely there to make up the height, or would it still resonate? Will get to it at the weekend!

Yeh thats what i was thinking last night! May have to re think that one!

irving2008
21-08-2014, 08:47 AM
You'll be surprised how much movement gets transmitted to the base, especially if the mill is cnc. If purely manual it's less of an issue. My mill was on a wooden stand but wasn't cnc. Even so, starting the spindle with a large boring head or fly cutter caused noticeable movement as no soft start.

JAZZCNC
21-08-2014, 10:50 AM
Irving is spot and the more ridged the better. I mostly build CNC routers not mills and often they go into sheds sat on bench's. My standard reply is this machines going to rock this shed and often the standard reply is a laugh thinking I'm joking.!! . . I'm not.!!
Can't tell you the number of times I've got emails within a day or saying "Your right last night I ran a job fast and the whole shed rocked". . Lol . . . . . Even had some one drive the gantry thru the shed wall. .Lol

CNC and the fast directional changes will easily rock a weak frame out of alignment or to bits etc or across the room if not fastened down.
Regards the electronics then I'm not a fan of fastening the box directly to a vibrating machine or it's frame but sometimes need must.!

EddyCurrent
21-08-2014, 11:26 AM
That's a nice piece of oak there but if you plan using that for the control cabinet don't. The enclosure should be made from non combustible material, also tannnic acid in the oak will react with the steel.

Jonathan
21-08-2014, 11:50 AM
Okay after managing to get on the computer i have made sure my plates are made of steel, and from what i can find the 2.2kw spindle is around 5.15kgs then the z axis is around 45kgs.

Just realised I forgot to reply to you about this. Using the script I posted here (http://www.mycncuk.com/threads/7355-What-size-servo-motor-do-I-need?highlight=matlab), the difference in torque required with and without the gas strut is around 20-30% and the absolute value is low enough for a 3Nm stepper motor to work well. I'm guessing a bit with some of the parameters, but suppose you put a 20T pulley on the motor and 30T on the ballscrew, the required torque (taking into account inertia of ballscrew, pulleys, carraige and motor, plus friction of bearings, ballnut etc) for 3m/s^2 acceleration is 0.87Nm without the gas strut which is well within the rating of a 3Nm motor below the corner speed. That means you'd easily get about 3.3m/min feedrate. The torque requirement for the same acceleration with 30:30T gearing is almost twice as much (1.67Nm), but if you use 20:20T it's 1.1Nm. The belt stiffness goes down with smaller pulleys, but it's still higher than the ballscrew torsional stiffness so not too big a concern ...

I'd recommend 20:30T pulleys on Z, as around 3m/min should be plenty for this size machine and you get higher resolution compared to 1:1.

totts
21-08-2014, 09:40 PM
Ahhh okay right so steel enclosure will be on order soon! And will add some braces to the frame, dont want this one walking through a wall! Haha.

Thankyou all for the help and advice, adding work... Tut :p haha

Thats good to know! Thankyou for the calculations, surprised at the gas strut adding that little!

totts
03-10-2014, 10:28 PM
Finally some more work, been a bit slow the past couple months with a few problems, but nearly finished the bed,

http://tapatalk.imageshack.com/v2/14/10/03/cae75ce83ee570b6d680473c6dfdc90b.jpg

Rail slots machined and fixingings tapped!

Ready to bolt the rails on!

http://tapatalk.imageshack.com/v2/14/10/03/c8a677f8d584bd380cb16f0bf6cc20c4.jpg

Slots machined and ready to accept 14mm t nuts

http://tapatalk.imageshack.com/v2/14/10/03/a312160baaa78a901d880485a24da3ea.jpg

Next on the list it to fix the rails on and finished grind the surface.

Then purchase the electronics cabinet, start painting and building and adding strengthening bars to the machine stand and a few little odd job bits! Light at the end of the tunnel??!

GEOFFREY
03-10-2014, 10:36 PM
Looking great, I think this will be a really nice machine. Great stuff. G.

JAZZCNC
04-10-2014, 10:37 AM
Light at the end of the tunnel??!

Ahh ahh ahh . . .. You poor dillusional Fool.!! . . . It's only just begun.!!!. . .LOL:joker:

Nice work by the way, impressive.!! . . . . wish I'd got a big surface grinder it really does make a difference in accurecy and finished look.

totts
04-10-2014, 12:25 PM
Thankyou, Yeh they are awsome machines, shame they are so damn exspensive! Lucky to be able to use one really.


Just changed all the countersunk screws to stainless ones, they were jolly tight! Doing their job !

totts
11-10-2014, 06:35 PM
More progress today, cut the rails to length and screwed them onto the bed,

http://tapatalk.imageshack.com/v2/14/10/11/ba769f561817a07a679dfd057dd726e4.jpg

Countersunk screws and dowels in place,

http://tapatalk.imageshack.com/v2/14/10/11/cade385617b5ecd1d684c9551d8dcc64.jpg

http://tapatalk.imageshack.com/v2/14/10/11/c8bd54e5e931c4d888df534f2291c138.jpg

http://tapatalk.imageshack.com/v2/14/10/11/40d772ee407307473782b1c330fd38e1.jpg

http://tapatalk.imageshack.com/v2/14/10/11/85df2b1d204578e2c604d35eda1c8332.jpg

Hopefully get it finished next week :)

EddyCurrent
11-10-2014, 06:42 PM
Great workmanship, it's a thing of beauty, the T slot bed especially.

Lee Roberts
11-10-2014, 07:56 PM
Looking really nice !

Question 1: What is the orange/red'ish color coming from the bottom of the rails?, looks like a layer of crafting felt or something?
Question 2: Am I right in thinking that, the dowels allow for fine adjustments of the rail towards the Datum Edge ?

.Me

totts
11-10-2014, 08:02 PM
Thanks,

Lee, its copper grease just running out a bit, didnt want any of the coolant corroding the bottom of the rail and causing the table to lift, although minimal i may aswell do it while i can.


Yes the dowels are there to push the rails towards the machined datum edge. Both edges 'should' be parrallel with one another.

Lee Roberts
11-10-2014, 10:00 PM
Ah right both cool ideas I haven't seen before so thanks!

Have you dialed them in with an indicator as well?

.Me

totts
28-11-2014, 08:01 PM
I will run a dti over them when i put the blocks on, but should be parrallel as the steps were machined in one setup. Touch wood!

So more progress!

http://tapatalk.imageshack.com/v2/14/11/28/7fc37a4d18cf2542a576bec5f6f9b081.jpg

Added the holes to fix a plate onto the back of the main pillar


http://tapatalk.imageshack.com/v2/14/11/28/4d73c60c7361dd444fe3c041a0b401b4.jpg

Mocking up the plate ready to drill and tap 20 holes with a hand drill :(

http://tapatalk.imageshack.com/v2/14/11/28/aff8cb7776d0cb6d2b833d603f467d6f.jpg

http://tapatalk.imageshack.com/v2/14/11/28/4c6f1d80391940bc5e8ec7a4b7c8cfe3.jpg

http://tapatalk.imageshack.com/v2/14/11/28/8014e12c595f87d9c3042dc354d1f5b8.jpg

Y axis plate all mounted with rails too, time to start adding the rest! Will be starting to get heavy!

totts
30-11-2014, 10:48 AM
Heavy z pillar going on now. Weathers starting to get cold now so i need to start priming some of the metalwork to stop it from rusting.


http://tapatalk.imageshack.com/v2/14/11/30/7c91f7fecea15f07441d6a5797301a0e.jpg

http://tapatalk.imageshack.com/v2/14/11/30/c8769d3fea8d93171bcd0514229a5e34.jpg

Lee Roberts
01-12-2014, 01:56 AM
Looking very nice!

Bustercnc
03-01-2015, 11:57 AM
Very nice build, I especially like the T-slotted x-axis bed.

Dave

Lee Roberts
03-01-2015, 09:00 PM
It is I'm very envious and can wait to see her cutting...

.Me

totts
03-01-2015, 09:05 PM
Thanks both of you, been really slow progress the past couple months had a member of family in hospital about a 100miles drive away in plymouth. And my daughter is due very soon so is going to be slow from now, but hopefully will get some time in the garage, :/

EddyCurrent
03-01-2015, 11:38 PM
Looks like proper quality, spot on.

GEOFFREY
04-01-2015, 01:57 AM
Started off looking awesome - now its getting better!!! G.

totts
11-01-2015, 10:44 PM
http://tapatalk.imageshack.com/v2/15/01/11/a69341f2e023e04f13d5d14082e20ded.jpg

http://tapatalk.imageshack.com/v2/15/01/11/4643d544db44adc36a2951860b984b6c.jpg

http://tapatalk.imageshack.com/v2/15/01/11/3db9363ff6736783ad0185775c9fa893.jpg

http://tapatalk.imageshack.com/v2/15/01/11/13ca397a061fce79ccd3f719dc31f9a8.jpg

Finally after waiting for a few parts in the post, limit switch and oil lines are all in place, y axis is complete, now for the x

totts
11-01-2015, 10:47 PM
Some of you may have noticed the m8 holes are close to the edge on the ball nut holder, unfortunately the dimensions i was given for the limit switch were wrong and i had to change the size to get it to fit. Grrr

GEOFFREY
12-01-2015, 12:33 AM
Well done. This site shows just what super work some people are able to produce. That is looking great. G.

kingcreaky
12-01-2015, 08:54 AM
first time ive seen this thread; just read with much interest. looking forward to the updates

Blackrat
12-01-2015, 06:39 PM
i like it, what are you using to drive the oil down the tubes ?

totts
12-01-2015, 08:06 PM
A couple of ideas, one is to either attach them onto a manifold with individual grease nipples, or attach them to an oil resivoir and attach a valve to presurise it to push the oil through.

Boyan Silyavski
13-01-2015, 06:23 AM
I obtained small 220V pump from an iron or steam cleaner, not sure. Payed 2 euro on a boot sale. Similar to the ones used in cars, that throw water on the front glass. However i prefer the 220V version cause no messing with transformers and so plus it vibrates instead of rotates, so pumps slowly, exactly what we need. The one i have is something similar to this one (http://www.ebay.co.uk/itm/321545978869?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT) , checked it with oil and it works. Believe the flow is adequate for the purpose.

Jonathan
13-01-2015, 12:31 PM
[QUOTE=silyavski;65874Believe the flow is adequate for the purpose.[/QUOTE]

Are you sure the pressure output is sufficient?

Boyan Silyavski
13-01-2015, 05:56 PM
Are you sure the pressure output is sufficient?

Not sure. But pressure for what? it just has to move the oil down, hence slightly help the gravity. Oil, not grease. Your oil system has pressure?

totts
13-01-2015, 09:45 PM
Getting cold in the garage ! :( need to make more bits now as ive nearly ran out of things to put together :s

Beds on now yay! Hopefully there to stay!
http://tapatalk.imageshack.com/v2/15/01/13/bbe48aa78c4faf38ef0412ec2756d1db.jpg

http://tapatalk.imageshack.com/v2/15/01/13/5f45a922b634c907f7802c757eac57be.jpg

http://tapatalk.imageshack.com/v2/15/01/13/2d0537c74ddeefbd7b8cb6885ea92899.jpg


And some more oil feed lines

http://tapatalk.imageshack.com/v2/15/01/13/e5220a1be793597a4b23ad1e9d9a1b9c.jpg

http://tapatalk.imageshack.com/v2/15/01/13/343e7e3cfac76298249c660a2d766d55.jpg

Boyan Silyavski
14-01-2015, 04:47 AM
Hi,
getting better and better. What size tubing and quick connector to screw to the linear carriages?

totts
14-01-2015, 06:17 PM
The are m6 in the carraiges and 4mm tubes with 2.5mm id

Lee Roberts
14-01-2015, 08:44 PM
I'm interested as well tots, any chance of some links or a point as to where you got them, "well gel" of your build mate.

EDIT: Are they hydraulic connectors when all said and done ?

.Me

Lee Roberts
14-01-2015, 08:50 PM
Sily, just search ebay for "air line push-in connectors" and they all come up, sweet !

.Me

totts
14-01-2015, 08:51 PM
Just old ebay,

http://pages.ebay.com/link/?nav=item.view&alt=web&id=261300410237

The some 4mm to 6mm connectors

http://pages.ebay.com/link/?nav=item.view&alt=web&id=121140904969

totts
14-01-2015, 08:52 PM
Yeh thats the fellas haha,

Lee Roberts
14-01-2015, 08:53 PM
Cheers mate looks like we posted at same time, this listing offers them all under one hood (the types you can get).

Pneumatic Push In Fittings Connector for Air/Water Hose & Tube Airline
http://m.ebay.co.uk/itm/131275393725

totts
15-04-2015, 10:10 PM
Blimey quite a while since i last updated, few things have changed but not many, due to the birth of my daughters i have been distracted :) haha.

Things are starting to get rolling again, ive had my spindle and vfd delivered, ive managed to get the bed running fairly parallel (within 0.02mm).

Surprised at how well these rails and carraiges run, i had the bed extended fully to one side, placed the dti on the bed and hit one end and it didnt even move 0.01mm :) very happy!!!

Anyhow z axis is being built, all plates and material has been machined, just needs assembling, need to start sorting out cable management :(. Pictures will follow soon!

Boyan Silyavski
16-04-2015, 01:43 PM
due to the birth of my daughters i have been distracted :) haha.

:applouse::applouse: :beer: Congratulations!

Lee Roberts
24-08-2015, 07:24 PM
Totts,
Wee want more! Weee want more !?!?

.Me

totts
24-08-2015, 07:38 PM
Haha sorry, been very busy, after an eventfull house moving, the machine has moved home!


I purposefully stopped building about 3months ago to stop adding too much weight.

Its still laying on its back on a pallet at the moment, having the 250kg tail lift struggle to lift it into the van, 3 of us needed to give it a helping hand!

Hopefully i will get it back on its feet in the next week and i can start making it heavy.

At least all this downtime has let me make all the small bits!

More photos and videos sooon! I promise!

Lee Roberts
25-08-2015, 11:39 AM
Sweet, good luck in the new house then will keep an eye out for the updates coming in :thumsup:

.Me

totts
01-09-2015, 10:51 PM
Nothing exciting but i have finally removed all the crap from ontop of the machine from the moving process.

The machine has survived just need to get a few people together to help me lift the machine onto its feet.

Then i can square up the rear pillar and away we go!

http://images.tapatalk-cdn.com/15/09/01/0f7630ab220df640b09799bdb82704d4.jpg

njhussey
02-09-2015, 03:48 PM
Looking forward to more updates soon!! I can relate to the clearing crap off the table....here was mine this morning.....second is this afternoon as I'm going to start back on it again ASAP.....

15992


15993

totts
19-09-2015, 07:19 PM
Busy day today!

http://images.tapatalk-cdn.com/15/09/19/75934ece91a120e64071286e663aadce.jpg

Didnt have a square big enough so i had to make one!


Moved it to its final position hopefully so i took the chance to use my dads level ;)


http://images.tapatalk-cdn.com/15/09/19/d24ebfe81637d5638fbb1ff9493dab52.jpg

http://images.tapatalk-cdn.com/15/09/19/ff402ca6d18223497bf4f8e8a64e2ace.jpg

Good enough i think!

Next was the rear z axis plate with the bearings ball screw and oil lines!


http://images.tapatalk-cdn.com/15/09/19/48c2655e727f8d6471402afe36b82cdb.jpg
http://images.tapatalk-cdn.com/15/09/19/f331b2eda1721b1249cb1ea84ebfa9b2.jpg
http://images.tapatalk-cdn.com/15/09/19/8e561f6314e66a2cd405f2040c748173.jpg
http://images.tapatalk-cdn.com/15/09/19/650dacb7ce4c0b9c6fd7033ab905b79d.jpg
http://images.tapatalk-cdn.com/15/09/19/79407a9c40f4632cb0ffbdb636c75809.jpg

Spindle enclosure, will do a bit of machining like this when its running to make a few parts for itself so i dont have to keep staying on at work. Then it will be filled with sand and the gas strut will be put to work.

Surprises me that i can twist the ball screw with my fingers and lift the axis up!


http://images.tapatalk-cdn.com/15/09/19/2f75ac140d177d4f4c4ac1c032e85a94.jpg
http://images.tapatalk-cdn.com/15/09/19/9bb2002524182c6cda5720798224ddc4.jpg


And the spindle placed in there for a test fit and quick measure up.

Y axis has a bit of backlash but im happy to just get it up and running for now! Think it may be the end suport of the ballscrew rather than the nut!

Runnout of the spindle with dowel pin is less than 0.01mm lucky!

And with me yanking the spindle and the dti on the nose i couldnt make it move more than 0.01mm happy as f@£!

Clean up time and tea time!

totts
19-09-2015, 07:23 PM
Oh an the spindle pictures i forgot!

http://images.tapatalk-cdn.com/15/09/19/b13e299ac986cc109a359dbf4a3e1124.jpg

http://images.tapatalk-cdn.com/15/09/19/30ded8a2a84c5900a78ffc3d691d016a.jpg

routercnc
19-09-2015, 08:17 PM
Lovely build totts !

Will you be using bellows over the rails and ballscrews?

Either way can't wait to see it in action . . .

totts
19-09-2015, 08:19 PM
Yeh will do just trying to source some, arc euro trade have some but just got to measure them up.

Same still loads to do unfortunately! Electronics! Ahhhhhh!

totts
19-09-2015, 08:35 PM
Oh and does anyone use a touch screen on mach? Or know where to get a resonable priced one?

Lee Roberts
20-09-2015, 09:16 AM
Hi totts, thanks for the update.

They pop up on eBay all the time, there is also a type that convert a standard monitor, it depends on what you go for but you can get like a retro fit panel/kit if you dont mind going to China, have a search on ebay see what comes up, loads cheaper than a proper one :).

This is the first one that came up but should get you started: http://m.ebay.co.uk/itm/160700957696

.Me

Lee Roberts
28-01-2016, 07:51 PM
Totts....come in..Totts...

.Me

totts
28-01-2016, 09:09 PM
I read you loud and clear!

After being messed around by a courier i finally have a free 600x500mm electronics enclosure, just sorting out the back panel, and cutting the sodes for the connections cooling and readouts, machine is pretty much the same, just waiting for its steppers to be connected after the enclosure is fully up and running, and to top it all off, ive changed my job, busy busy busy hahaha


Simon

Lee Roberts
29-01-2016, 09:47 AM
I read you loud and clear!

After being messed around by a courier i finally have a free 600x500mm electronics enclosure, just sorting out the back panel, and cutting the sodes for the connections cooling and readouts, machine is pretty much the same, just waiting for its steppers to be connected after the enclosure is fully up and running, and to top it all off, ive changed my job, busy busy busy hahaha


Simon
Cool, I just can't wait to see her up and running mate that's all :), I actually came here to double check the air line fittings, where did you get the tubing from, Pegasus have it listed but it doesn't quite look the same as yours? Is it just the clear stuff but happens to have a blue tint to it or?

Sorry to be picky.

.Me

totts
29-01-2016, 02:18 PM
I had mine from my old work place, they bought it from SMC. https://www.smc.eu/portal_ssl/WebContent/corporative/products/products.jsp?tree_options=tree_products.js&tree_state=0&tree_highlighted_node=999999

They are pretty exspensive though.

It is coloured /tinted blue on purpose.

Alough i wish i had used nylon tubing as i dont know how long the pvc pipe will last with the oil.


Simon

Noplace
29-01-2016, 09:03 PM
Hi could you please let me know what fittings do you use for the oil lines? I'd like to switch to something like this for my gantry on my machine but don't know what to search exactly, I'm using hiwin guides which have M6 holes for the grease nipples, would lines like what you have work for grease as well? and what do they call the piece that hooks all lines together so that you fill them all up from one point?

thanks!

totts
29-01-2016, 09:05 PM
Just old ebay,

http://pages.ebay.com/link/?nav=item.view&alt=web&id=261300410237

The some 4mm to 6mm connectors

http://pages.ebay.com/link/?nav=item.view&alt=web&id=121140904969




Simon

totts
29-01-2016, 09:08 PM
Hope this helps, they are pneumatic air fittings, are availiable all over ebay different threads, tube sizes and options :)


Simon

Noplace
31-01-2016, 10:43 AM
thanks very much, sorry another noob question but if I were to pump from a grease gun, any hint on what type of nozzle to get? for the same size you are using

totts
31-01-2016, 10:51 AM
Thats okay we are all a noob at some point, i still am haha, im not quite sure what you mean,

Do you mean how would you get from grease gun to the pipes? If so then i would make a manifold which would hold the fittings one side, and the original grease nipple the other.


Simon

totts
15-03-2016, 09:22 PM
So its been slow but ive cut my enclosure and started wiring, its not my strong point so im taking it nice and steady!

http://uploads.tapatalk-cdn.com/20160315/c4e815302486a9976475166328ec9dc0.jpg


Simon

Lee Roberts
17-03-2016, 08:10 PM
What are the 5 grey looking things in the middle Si ?

Good to see your still pushing on with it all :)

.Me

Clive S
17-03-2016, 08:48 PM
They look like solid state relays

totts
17-03-2016, 09:17 PM
They look like solid state relays

U guessed correctly! :)


Simon

routercnc
17-03-2016, 11:04 PM
I messed around for a while with those for my control box but in the end I could not get them to do what I wanted. I think I was trying to use them to switch the main toroidal power supply using a DC circuit or something like that.

I used a contactor in the end which works a treat and is the right thing for the job. Why so many and what are they switching?

By the way, loving the machine so far.

totts
17-03-2016, 11:21 PM
Thats what i wanted, using them with my 24v psu to switch on the toroidal ps, spindle, cooling, estop, program estop and coolant. Using the 24v for switching. I hope it all works lol


Simon

JAZZCNC
17-03-2016, 11:35 PM
Solid state relays are not always good thing to use because they often fail ON.!

totts
17-03-2016, 11:42 PM
Yeh ive heard that, the electricians in work have told me a few stories, which im surprised the fail on, i have two relays operating on the estop so i hope thats enough otherwise i will go back to normal relays.


Simon

Davek0974
18-03-2016, 09:17 AM
Please only use normal relays or contactors for e-stop, SSR's are really only safe for loads like heaters and lamps, i learnt this years ago when i was doing R&D for printing process and finishing machinery. They fail regularly and 99% will fail ON not off. Even when used for heaters you need to use sensors for over-heat which happens when they fail.

If using for motors, always fit a good snubber network to help protect the SSR.

Loving the build BTW;)

totts
17-08-2016, 09:35 AM
Morning all, managed to get it up and running and wondering if anyone can give me some electrical advice,

I'm currently using an akz250 (usb Bob) no I know that u need a stable 5v to run? Also using dq860ma steeper drivers.

The problem is when I run a long program like the one in the picture, I loose steps in the x axis, one roughing cut depth is different to the next.

Now I've tried slowing the motors down and changing the acc, and the problem still happens.

I had a quick look at my wiring and ran a multi meter over the terminals, I have 4.45v going to (can't remember if it was step/dir) and 2.7v on the other terminal,

Also my drive has an enbl + / - terminal, do I need to wire 5v signal to this? As my drive is working without it?

Thanks


Sent from my iPhone using Tapatalk

totts
17-08-2016, 09:51 AM
http://uploads.tapatalk-cdn.com/20160817/06e231d76ebc9d0c44c31e2e2fd89c94.jpg


Sent from my iPhone using Tapatalk

Clive S
17-08-2016, 12:42 PM
Nice to see you have it up and running. I don't know anything about that board but are you powering it via the USB if so can you power it from a separate power supply?

Are you running the drives at about 68V?

You don't need to connect to the enable terminal, that won't effect missing steps etc.

JAZZCNC
17-08-2016, 02:39 PM
Possibly due to the Step pulse being on the wrong side of the slope. Commonlly step pulse is on the rising edge but in some cases drives may be set so on the Falling edge. If this is the case and on wrong side then can lose one step with every direction change.

To check this write program that goes back n forth few hundred times on that axis. Mark the start point and check it goes back to same point after the moves.

If doesn't then change the Step low active in Motor Outputs. This will put the Step pulse on the opposite edge.

totts
17-08-2016, 02:52 PM
It's a 70v psu I can't remember the exact voltage from the psu,

The akz250 is a Chinese board [emoji15]. I m pretty sure I can wire a different supply to it by using this diagram -


http://uploads.tapatalk-cdn.com/20160817/4c6869a160eb4c5e497794325972c35b.jpg


Sent from my iPhone using Tapatalk

totts
17-08-2016, 02:54 PM
Possibly due to the Step pulse being on the wrong side of the slope. Commonlly step pulse is on the rising edge but in some cases drives may be set so on the Falling edge. If this is the case and on wrong side then can lose one step with every direction change.

To check this write program that goes back n forth few hundred times on that axis. Mark the start point and check it goes back to same point after the moves.

If doesn't then change the Step low active in Motor Outputs. This will put the Step pulse on the opposite edge.

This would make sense as the toolpaths have a lot of direction changes due to it being an adaptive toolpaths, so if I change step low active will this run the motor in the opposite direction?


Sent from my iPhone using Tapatalk

JAZZCNC
17-08-2016, 05:28 PM
This would make sense as the toolpaths have a lot of direction changes due to it being an adaptive toolpaths, so if I change step low active will this run the motor in the opposite direction?


Sent from my iPhone using Tapatalk

No it shouldn't but if it does then just go into Homing and Limits and select Reverse. You may need to change the Home direction.
Don't Change the Dir Active leave that the same as it can have an affect on drive.

However Like I said wouldn't change it without knowing for sure and the only way is to mark and run test code.

totts
17-08-2016, 07:02 PM
Thanks will get some code running on it when I can get to it next and set up a dti hope this works!


Sent from my iPhone using Tapatalk

totts
19-08-2016, 10:54 PM
Okay so I ran 1000 lines of code from the settings I'm on and It went back to zero, I changed the step active and same code no missed steps.

I then ran my code that I've been having trouble with, about 4000 lines and I didn't have no missed steps, but I have this new problem when I jog my machine it Judders whichever settings I use and at whatever speed, but when I run a program it doesn't judder , weird huh?


Video -

https://vimeo.com/179512381


Sent from my iPhone using Tapatalk

totts
19-08-2016, 11:01 PM
P.s I know it's stalling it does it even if I change the acc and speed. It does it in every axis


Sent from my iPhone using Tapatalk

JAZZCNC
19-08-2016, 11:10 PM
had loads of problems with keyboards so try different keyboard before anything else

totts
19-08-2016, 11:12 PM
I've used a pendant and a keyboard same problem :(


Sent from my iPhone using Tapatalk

A_Camera
23-08-2016, 11:08 AM
P.s I know it's stalling it does it even if I change the acc and speed. It does it in every axis If you have stalling problems then you must start by fixing those, before you start milling or try to figure out the missing steps. It may be the stalling which causes the issues you have. Anyway, stalling can be caused by too high speed and acceleration or some mechanical or electrical problems. Locate the source and fix that.

A_Camera
23-08-2016, 11:11 AM
I've used a pendant and a keyboard same problem :(Disable jogging and fix the stalling issues first. You must be able to run rapids repeatedly without stalling. Once you can do that then you can start checking for the rest of the problems.

A_Camera
23-08-2016, 11:20 AM
It's a 70v psu I can't remember the exact voltage from the psu,

The akz250 is a Chinese board [emoji15]. I m pretty sure I can wire a different supply to it by using this diagram -


http://uploads.tapatalk-cdn.com/20160817/4c6869a160eb4c5e497794325972c35b.jpg


Sent from my iPhone using TapatalkThat diagram shows only how to connect an external PSU for the drivers, not the BoB. Anyway, if there is no external +5VDC input to the BoB you can always split the USB cable, separate it from your PC and feed it through those two wires. It is not a good idea to take the 5V from the USB because that is not always able to deliver enough power, or the voltage is too low for your opto couplers. Generally an external power supply is preferred because it is better and more stable.

totts
23-08-2016, 11:21 AM
Disable jogging and fix the stalling issues first. You must be able to run rapids repeatedly without stalling. Once you can do that then you can start checking for the rest of the problems.

I set up the machine and had no problems with short code but long code I found I had missed steps (after machining that part) so I then ran code in rapid

G00X10Y10Z10
G00X0Y0Z0

Repeated this about 1000 times and it went back to 0

After running a few test in jog mode the motor stalls as per video.

I'm hooking up a new computer tonight to determine weather it's the pc or the Bob.


Sent from my iPhone using Tapatalk

A_Camera
23-08-2016, 11:30 AM
I set up the machine and had no problems with short code but long code I found I had missed steps (after machining that part) so I then ran code in rapid

G00X10Y10Z10
G00X0Y0Z0

Repeated this about 1000 times and it went back to 0

After running a few test in jog mode the motor stalls as per video.

I'm hooking up a new computer tonight to determine weather it's the pc or the Bob.


Sent from my iPhone using Tapatalk


So you have no stalling at full speed? Run this a 1000 times:

G00X(maximum X)
G00X(minimum X)

...to check X and likewise for Y and Z separately to check stalling. Running as short as to 10 units (inches or mm?) can be too short to test for stalling, but it is enough if missing/extra steps are needed to be checked. Also it is better to separately test the axes because running all three at the same time may result in less speed per axis than the maximum.

totts
23-08-2016, 11:28 PM
I had previously ran the x axis separately. And the y,

Some progress!

I have tried a new computer tonight and all the jerky ness has gone so I'm going to get a new desktop pc sorted and run my tests all over again and hopefully get some parts made!


Sent from my iPhone using Tapatalk

totts
18-09-2016, 09:32 PM
Okay right after a new pic, running loads of test programs and the program itself in fresh air and then coming back down to a dti, and it returns to zero, I decided to run a test part.

Run the test part and I had it skip again argh!

I ran the program in fresh air but this time, I ran it with the spindle on!

And it skipped, so I've come down to interference.

Problem is, all my cable is cy cable, all grounded at one end, checked the earth continuity all is well.

But I have a cy cable on the vfd to motor cable which is earthed at one end and wondered if this could put interference down the earth? I've placed vfd at one end of my garage and the control on the other and currently running the program again so we shall see if I get the same problem.


Sent from my iPhone using Tapatalk

routercnc
18-09-2016, 10:09 PM
After a few mystery e-stops I tried putting a filter onto the mains side of the VFD but no improvement. I then ran an extension lead from the other end of the workshop and plugged the VFD into that, instead of the row of sockets for all the CNC stuff (PC, monitor, control box power mains supply). Not a single problem since and has been good for months. Note that the VFD and motor cables themselves are still in the control box, next to all the other electronics. It's just the power lead that is connected remotely and that has solved it.

totts
18-09-2016, 10:11 PM
Interesting, my vfd is on a different socket to the rest of the control, but it is on the same ring main just two sockets apart.


Sent from my iPhone using Tapatalk

totts
18-09-2016, 10:47 PM
Well the program has finished and it still moved so I'm going to take the shield off the earth tomorrow


Sent from my iPhone using Tapatalk

JAZZCNC
18-09-2016, 11:44 PM
You haven't earthed the PC to the control box have you.?

Also do you have Earth on the Frame.? I'm presuming all your Earths go to one Star point.?

Boyan Silyavski
19-09-2016, 12:23 AM
Nothing can cure a crappy board with poor filtering on the signals / i don't know what that is exactly but i know some boards are good :angel: and have it/ .

I had last week's similar problems, fortunately not with the motor output signals, just probes, switches and PWM output. Neiter filtering of line input, grounding, shielding or whatsoever helped. One of said boards worked well in other machine. All worked fine untill i switched my servos.

But in you case a shielded cable from board to motor drive might help. I have resolved a friends machine similar problem once, changing said cable with a shielded one. Problem solved. In fact his cable was shielded before but wires at end were very large, So i cut them at minimum so all is shielded. Changed cable just to be sure though, as i had a better one at that moment.


Are your cables between this and that shielded?


And by that mean that the shield must be grounded to case

totts
19-09-2016, 07:49 AM
I've tried to make all my signal wires shielded, there are just over two inches long at either end.

Machine frame is earthed via the spindle from one point and all shields are all going to one point. Pc control cabinet is earthed too.

But my pc has a shielded USB cable which means the pc and the control box is actually earthed together and I have had a few false errors at some point saying it was disconnected.

Sent from my iPhone using Tapatalk

Davek0974
19-09-2016, 08:16 AM
The case of the pc should not be connected directly to the machine, if it is, try removing that link, I have suffered with this.

is the BOB ground connected to the chassis? pretty certain it should not be, none of my boards were.

totts
19-09-2016, 08:18 AM
No bob ground/neg isn't connected to earth, will remove the earth from the USB cable tonight


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totts
19-09-2016, 11:09 PM
So disconnected my USB shield from one end (control end) ran a program only moved 0.3mm instead of the 1.2mm, but found the resistance was high in the earth, the continuity on my multi meter was struggling to pick it up, I checked continuity through my control cabinet earth, which in turn is connected to earth ring main, pc and the USB again, managed to my continuity back, will run a program agin and hopefully will get that 0.3mm back!


Sent from my iPhone using Tapatalk

Boyan Silyavski
19-09-2016, 11:52 PM
Today i cured all my problems by connecting my VFD ground directly to metal box with electronics inside. Incredible but yes.

As i read that Dean suggested no ground from box to PC, i remembered that when was desperate i did exactly that. Took off ground from PC side and spindle started rising and slowing speed. I said to myself that things are getting worse like that, but as the ground to box was still connected i started touching it around. Touched to ground on socket and was better, touched to PC box- better, then accidentally touched to VFD ground and voila, all was fine. They have common ground at socket, but cable between boxes cured all problems.

totts
20-09-2016, 12:06 AM
So you have USB shield earthed at box end and the vfd earthed there too? Have you a shielded cable from ur vfd to motor?


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Boyan Silyavski
20-09-2016, 12:31 AM
I have all earthed at box body -PC, all Transformers inside, etc. The VFD is outside, just near the box. Yes it has screened cable to the spindle connected both ends. So it's connected to machine. Machine is also connected to box. So all also is grounded together at socket. Go and figure then why problems disappeared when i connected VFD box with big box. In other words- they were grounded at socket and machine prior to the bypass cabling that solved problems.

I could only say that my stupid persistence lead to a result. I was many times at point of taking my big hammer and ...

nairepooc
20-09-2016, 11:08 AM
All this talk of Grounding and Earthing, is making me even more confussed!
Is Grounding connecting to 0V dc and Earthing to a Star earthing point or am I missing something, or are we mixing up the terms?

Clive S
20-09-2016, 11:25 AM
All this talk of Grounding and Earthing, is making me even more confussed!
Is Grounding connecting to 0V dc and Earthing to a Star earthing point or am I missing something, or are we mixing up the terms?Grounding and Earthing often creates a lot of confusion and to some extent depends how old you are. But you don't connect your DC ground to the Star point which is the point where all the screens connect to and then that is connected to the AC earth. The reason for the Star point is to get rid of earth loops (or ground loops if you are old).

Sometimes you have more than one DC power source and again somtimes you have to connect the various DC power -ve together. Hope this helps a bit.

Boyan Silyavski
20-09-2016, 01:17 PM
Sorry, my mistake then. In my mother language -ground and earth is the same word, not 2 different. So when i say Ground or Earth, i mean the same. Stick 2m long in the ground that is connected to all grounds in house line electricity, mind not the 0 or phase. If we are talking for DC i say Negative or Common ground. I am not sure that's right, but as English is not my native language ...

Davek0974
20-09-2016, 02:41 PM
Dictionary wise both are same.

But in electrical engineering context both words differ in scope. Ground is a general term that refers to a reference potential against which all voltages are measured. Earth is same as ground but used in context of power systems because the ground here is implemented by burying copper conductors deep down into Earth.

Since Earth has minerals, moisture and it has practically infinite volume, the current flow is only limited by contact resistance between ground/earth conductor and soil. Because of this, on the distribution side, the neutral is connected to earth. On receiving side, fault current from one of the phases can flow into the local earth conductor and make its way to the neutral at distribution side. Apart from being a sink for fault current, the Earth conductor also serves as a return path for instrumentation systems.

:)

njhussey
20-09-2016, 02:44 PM
Dictionary wise both are same.

But in electrical engineering context both words differ in scope. Ground is a general term that refers to a reference potential against which all voltages are measured. Earth is same as ground but used in context of power systems because the ground here is implemented by burying copper conductors deep down into Earth.

Since Earth has minerals, moisture and it has practically infinite volume, the current flow is only limited by contact resistance between ground/earth conductor and soil. Because of this, on the distribution side, the neutral is connected to earth. On receiving side, fault current from one of the phases can flow into the local earth conductor and make its way to the neutral at distribution side. Apart from being a sink for fault current, the Earth conductor also serves as a return path for instrumentation systems.

:)
Look who swallowed a dictionary.....nice clarification, cheers Dave 😊

Clive S
20-09-2016, 06:15 PM
Yes Dave good clarification one of the problems that has been highlighted is that different disciplines treat the words different such as in electronics PC boards often have a ground plane that is not connected to earth but to DC ground or signal ground in this case ground is not earth.

Davek0974
20-09-2016, 07:17 PM
Yep, it's a thorny subject, don't forget the chassis ground, signal ground, RF ground - there are loads of grounds but they do not have to be connected to earth :)

totts
20-09-2016, 09:36 PM
My head hurts! Haha think I'm going to come back to it when I have more than half an hour to play!


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picatinny
22-09-2016, 05:45 AM
Keep on the good work mate

picatinny
22-09-2016, 06:12 AM
Can you post more pictures