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View Full Version : BUILD LOG: New Build, Aluminium Frame Router/Mill



Davek0974
20-02-2016, 04:55 PM
First router/mill build, I've built two tables before but they were for Plasma cutting, this time I wanted something that can cut wood, plastics, aluminium etc.

I thought up some ideas but after asking on here, they were dumped for tried and tested designs to save risk of wasting cash, basic ideas were courtesy of JazzCnc - thanks for the kick-start :courage:

Practically all-aluminium structure, 3NM stepper motors, digital drives, 1610 ballscrews, 20mm HiWin motion, Mach3 control via a UC100 motion controller. Y axis is twin screw with single motor and belt drive via 15mm HTD belt, X axis is single screw/single motor again with 15mm HTD belt. Currently ALL pulleys are 20t 1:1 ratio but being belt/pulley drive will mean I can easily adjust ratios later depending results.

I had a large lump of cast iron 410x600x18mm which was machined on both faces - this is to be the main bed of the CNC, I will use a sit-on bed of 12-15mm machined aluminium for metal work and an MDF bed for wood and plastics.

On order from Aliexpress I have the ballscrews, motion, support bearings and a 2.2kw water cooled spindle and VFD. Intent is to control the VFD/spindle speed via the 0-10v BOB I have got, also got a dual relay board for the water pump, coolant etc.

Most of the aluminium has arrived, it's all 20mm and 15mm machined tooling plate, surface finish and dimension is perfect. The structural beams are 45x90mm heavy-duty section.

First cuts were made today, started on the gantry support arms...
17644
Might not look much but thats two heavy slabs of 20mm ally, my idea is to build and get it running then remove the supports and mill them to the customary inverted L shapes and radius the corners for safety.

Fun times ahead but having built two CNC's before, this one should hold few surprises I feel:thumsup:

Davek0974
21-02-2016, 05:17 PM
Bit more...

Z Axis front plate...
17658
Yes, that is a boo-boo in the bottom right corner of the pocket, what happens when you grab the Z axis handle on the mill instead of the Y axis, D'oh!

Its only about 0.5mm deep so will not affect anything.

Z axis motor mount plate...
17659

Coming along nicely :)

Davek0974
24-02-2016, 12:25 PM
Also building a fog-buster style coolant unit, seems the best choice, not sure what to fill it up with though???

Davek0974
25-02-2016, 07:42 PM
Little more progress, started getting parts ready to assemble the Z axis...

17717

All the motion parts arrived today, along with the spindle and VFD :)

njhussey
25-02-2016, 08:04 PM
Looking good Dave, you'll soon be up and running!

sinnsvak
25-02-2016, 08:11 PM
Looking great so far! In this last picture, will that stick out be for the X-axis movement?

If i may ask a question about the Z-frontplate, that cutout for the Z-axis nut, how thin can the wall be in that area before one can notice any weakness?

I dont have a fog buster, but a simple mister from aliexpress, and alcohol works great for my projects. No cleanup needed afterwards, but if you need more lubrication to handle i.e. gummy alu, you gonna want something oily.

Davek0974
25-02-2016, 08:26 PM
Yes, thats the plan, it protrudes enough to get me over the screw so i can fit a drop bracket for the nut. The cutout clears the Z axis motor body.

The Z front plate and the very front plate where the tool mounts are 20mm thick and needed 7.5mm taken out of each to align the rails and screw. I don't feel that will make any difference at all to strength - the tool mount plate is also reinforced by having the linear rails bolted to the back of it. The rear Z plate is has the Z axis linear carriages aligned directly with the support plates (shown in the pic) for the X axis linear carriages - the forces are transferred directly from Z to X.

Having built two plasma tables out 3mm steel which were still very sturdy, this thing is being built like a mini battleship!

Nr1madman
25-02-2016, 09:19 PM
Awsome work!

sinnsvak
25-02-2016, 09:32 PM
Yes, thats the plan, it protrudes enough to get me over the screw so i can fit a drop bracket for the nut. The cutout clears the Z axis motor body.

The Z front plate and the very front plate where the tool mounts are 20mm thick and needed 7.5mm taken out of each to align the rails and screw. I don't feel that will make any difference at all to strength - the tool mount plate is also reinforced by having the linear rails bolted to the back of it. The rear Z plate is has the Z axis linear carriages aligned directly with the support plates (shown in the pic) for the X axis linear carriages - the forces are transferred directly from Z to X.

Having built two plasma tables out 3mm steel which were still very sturdy, this thing is being built like a mini battleship!

Thanks, I also think the forces are pretty much directly transferred from Z-carriages to X-carriages. One important task the z-plate also does is keeping the rotational forces at bay, and I agree, 7,5mm less wont make a speck of difference.

I will look over my own drawing and see if I cant do the same.

njhussey
25-02-2016, 09:44 PM
.......this thing is being built like a mini battleship!

I know that one, my Z front plate is 40mm thick...think I only took a similar amount out of that, overkill??!![emoji15]

Davek0974
25-02-2016, 10:42 PM
Better over than under ;)

Davek0974
26-02-2016, 07:34 PM
Day off today so hit the project...

X / Z axis finshed...
17730

Rear face of the tool mount plate with the linear rails...
17731

Front of the Z axis with some linear rail carriages in place...
17732

Back of the Z axis with the X axis carriages in place...
17733

Rear frame support plate fitted to the main beams...
17734

Next up is the front frame plate and mount for the Y axis motor. :)

Davek0974
27-02-2016, 03:45 PM
Bit more today...:calm:

The bare frame - extremely rigid, surprised me!
17744

Inside of the front plate (maybe the back, not sure yet) idler bearings to shift the belt path...
17745

The Y axis screws temporarily fitted...
17746

The gantry being built up...
17747

The Z axis in place...
17748

Z axis lifter screw and motor fitted...
17749

So far, my CAD efforts have been 100% perfect, every single part drawn has fitted just where it should be :calm: Torsionally, the gantry is very stiff - pushing on one side brings an immediate response from the other which is good, the Z axis looks like it will be just as tight.

Now i need to fabricate an idea for a method of joining the Y axis nuts to the gantry cross-beam.

JAZZCNC
27-02-2016, 05:02 PM
Tuff littel Bird ain't she.. .:pirate:

Davek0974
28-02-2016, 09:16 AM
Certainly is Jazz, this thing is probably more rigid then 'Mr Flexy' the Bridgeport ;)

Davek0974
28-02-2016, 02:40 PM
Small progress today, mostly tidying up loose ends and fitting parts...

17750

njhussey
28-02-2016, 03:33 PM
Looking a nice little build, still lots of fun stuff to do yet!

Clive S
28-02-2016, 03:39 PM
Is that a belt sander in the background? Warco!!

Davek0974
28-02-2016, 03:51 PM
Is that a belt sander in the background? Warco!!


Yes it is, 4" belt vert/horiz, it's one of the most used tools and one of the most gutless i'm afraid, I really need to build or buy a decent unit with a Hp or two behind it. You have to take your time on it - press on a bit and it just stalls out.

Cheap though and has done a lot of work.

Davek0974
01-03-2016, 08:11 PM
Slight boo-boo uncovered tonight, the belts arrived and the teeth were bigger than i allowed for in my serpentine arrangement, this caused the opposing sides of the belt to rub against each other at the idlers...

17771

First option for fixing it was to order up some smaller diameter bearings, should work ok.

routercnc
01-03-2016, 09:29 PM
Hi Dave,

Looking great so far. The other option is to slot the holes for the lower bearing idlers - might have to be slotted at a slight angle to avoid hitting the stepper.

Davek0974
01-03-2016, 10:15 PM
Yes that would be an option, it would mean having bolt heads on the outside though, not a critical point though.

Will try a smaller bearing, 24mm dia instead of 26mm, should be enough.

sinnsvak
04-03-2016, 03:06 PM
How are the solution for the X-ballnut coming along? Kinda stuck on the same thing myself.

Davek0974
04-03-2016, 08:13 PM
I have managed to use the standard ballnut mount blocks for all axes i hope, i just need to finish machining the spacer blocks for the y axis and do the fitting, hopefully be all axes connected this weekend :)

Davek0974
05-03-2016, 06:54 PM
Stripped it all down today for final finish and fit, ran out of time to start the rebuild but hopefully tomorrow will get some picture update.

I was going to put the Y axis motor to the rear of the frame but it didn't play nicely and would cost me some Y traverse so I'll leave it at the front. The new idler bearings seem to have sorted the belt issues out, hopefully the motor adjustment slots will be enough to take up the slack without getting a shorter belt.

My plan is to mount the rails and screws square to the beams, its all pretty rigid and square when assembled so with a bit of luck it will all work out exactly as the drawings indicate.

Davek0974
06-03-2016, 03:30 PM
Got some motion assembled today, final fitting takes a lot of time...

17862

17861

17863

Next up is making the bracket for the X axis motor. Then i might remove the grease nipples on the lower X carriages as they are costing me 20mm of travel by hitting the side frames.

A little more fiddling here and there and we should be ok to start planning wiring runs etc.

sinnsvak
06-03-2016, 04:48 PM
I like how simple it looks, but I know how much careful planning/drawing it took to get there.

Davek0974
06-03-2016, 05:27 PM
I like how simple it looks, but I know how much careful planning/drawing it took to get there.

It is pretty simple, I am not claiming credit for the design basics as it was given to me by a friend, but the subtle details are mostly mine.

One thing for certain though is that it's as rigid as a rigid thing at a rigid party and it weighs a ton! All of which are good properties i think ;)

Confidence is high as they say.

Drawing it 100% in CAD has been a money and nerve-saver, I am happy i spent the time drawing it all up, It has needed a couple of shims to assemble it but the thickest one was only 0.30mm which i think is pretty damn good and totally attributable to the way i had to cut the beams (manual chop-saw). The rest of it, like the Z axis and X axis have been just a matter of machine-and-fit, pure pleasure ;)

JAZZCNC
06-03-2016, 05:45 PM
One thing for certain though is that it's as rigid as a rigid thing at a rigid party and it weighs a ton! All of which are good properties i think ;)

So Black Adder you saying one my Baby's is Simple Fat Lass who's Harder than Hard thing in Hard place.!. . . . I'll be sending Hot poker your way.:devilish:

Anyway who said was your friend:hysterical:

Davek0974
06-03-2016, 05:50 PM
Ok I presumed friendship ;)

Certainly tough-nut though ;)

JAZZCNC
06-03-2016, 06:01 PM
Ok I presumed friendship ;)

Know what they say about Assuming.??? . . . .Thou ya got it right this time.. :thumsup:


Certainly tough-nut though ;)

Should Expect nothing less from Yorkshire Lass.!. .:boxing:

Davek0974
06-03-2016, 06:07 PM
Know what they say about Assuming.??? . . . .Thou ya got it right this time.. :thumsup:



Should Expect nothing less from Yorkshire Lass.!. .:boxing:

I hear the tea is pretty good stuff too ;)

Davek0974
07-03-2016, 08:46 PM
One almost oversight i spotted tonight - the holes on the ballscrew nut flanges, i presume these are for grease nipples?

To get to my Z axis ones will mean taking the bed off - no big deal there but the z axis one is buried.

The question - how often do screws need greasing?

Davek0974
09-03-2016, 07:28 PM
Got the Y axis screws synchronised and belt fitted tonight, fine-tuned the ballscrew nut brackets and the bottom end is just about done, threw the bed and over-bed on for a photo...

17900

The 15mm alu over-bed will drilled/tapped for mounting studs etc, it's a little shorter than i would like and cost me about 50mm of Y travel but it will do ok for a while.

Just waiting for some alu bar to arrive for the X axis motor mount and we will be wiring up for motion testing :)

sinnsvak
09-03-2016, 07:32 PM
I think for the size, it will perform very well!

Davek0974
09-03-2016, 07:56 PM
As they say, confidence is high :)

It does feel good, nice and rigid, plenty of z height range, easy-change alu bed or mdf spoil-board, if it performs as well as i think it will, I will be a happy chappy.

I need to figure out some chip/splash skirt for the bed but that will come together soon hopefully.

Lee Roberts
09-03-2016, 11:04 PM
Looks solid Dave, good luck on the big day :thumsup:

.Me

Davek0974
10-03-2016, 07:51 PM
Got the X axis motor mounted and belted up tonight, all ready for temporary wiring and motion tests this weekend :)

routercnc
10-03-2016, 08:19 PM
Looking good Dave.

Something to think about is whether you want to be able to quickly see the X axis belt to check the tension and general health over the months and years ahead.

Can the machine be tipped up on its side to look underneath? Or maybe a small window cut into the end plate with a perspex cover. Not critical, just a thought.

Davek0974
10-03-2016, 08:26 PM
With an assistant, it can be up-ended onto the back plate, the bed will also be pretty easy to remove - just few allen screws and it will slide back or right off if wanted, this would be the preferred method of access to the screws and belt inside.

Davek0974
12-03-2016, 05:20 PM
We have motion :)

Running a square at the limits...
https://youtu.be/tZ2FtlGJOf4

Air-cutting a 280mm circle...
https://youtu.be/fF-aAMadkAw

There is a frightening amount of power behind those axes, I tried applying some load but even with me forcing it as much as i could it made no difference :)

Then i moved on to limit switches - X first, using inductive sensors...

My brilliant idea was to use one sensor on the moving part of the axis and have two adjustable targets, all good so far;)

Got that lot fitted and set X++, X-- and X-Home all to one input (this was the smart bit I thought)

But....

The limits work but I cannot jog off of either end - it just shows "Limit switch triggered" immediately after pressing Reset, and the home works but immediately throws a limit fault after homing.

So...

Am I correct in now thinking that I am indeed a twat and you must have TWO sensors or have I missed something simple??

These sensors seem to not flip on or off - they flicker a little as the target gets near - is this normal??


Close but no cookie yet :)


Here's the rough lash-up of my panel...
17911

Clive S
12-03-2016, 05:50 PM
Am I correct in now thinking that I am indeed a twat and you must have TWO sensors or have I missed something simple?? Brill it is always good to see it move for the first time .

You only need one switch if it is traveling there is a checkbox in Mach3 so that you can jog off the limits. On the setting page I think but I would have to check

JAZZCNC
12-03-2016, 05:55 PM
Dave go into General Config and turn off "Home With safety" then you can share the swithces for both.

Then turn on Auto limit overide and you'll be able to reset limit when triggered and jog off.

Davek0974
12-03-2016, 05:55 PM
I thought that too, the only one i could see was "Home SW safety", tried that but made no difference.

These sensors seem to not flip on or off sharply - they flicker a little as the target gets near - is this normal??

Maybe the flickering is causing the issue and I've bought a load of crap sensors??

JAZZCNC
12-03-2016, 05:59 PM
what kind of sensor.?

Davek0974
12-03-2016, 06:04 PM
what kind of sensor.?

These ones, they seemed to be the most common type, NO, NPN.

LJ12A3-4-Z/BX

JAZZCNC
12-03-2016, 06:15 PM
These ones, they seemed to be the most common type, NO, NPN.

LJ12A3-4-Z/BX




How are you connecting the switches to the BOB.? What pin does the Black wire go to.?

Davek0974
12-03-2016, 06:32 PM
On my CP0-10V bob from CNC4YOU it goes to pin 10 and i am using input 10 in P&P settings, you can see the LED on the back of the sensor flicker as the target is starting to cover the end of the sensor, when fully covered the LED is on stable.

The sensors are powered from the 12v output on the BOB as shown in their diagrams.

JAZZCNC
12-03-2016, 06:50 PM
The manual shows PNP swithces and your using NPN. Take 12V to pin 10 and Put Black wire to Gnd. Then it will work.

Davek0974
12-03-2016, 07:08 PM
The manual shows PNP swithces and your using NPN. Take 12V to pin 10 and Put Black wire to Gnd. Then it will work.


This is the manual i used http://cnc4you.co.uk/resources/CP0-10V.pdf, the switches and sensors pull the pins down to activate, I guess thats active low, and i thought NPN was sink or active low output i.e the pin is pulled high internally and the sensor pulls it low?

Davek0974
13-03-2016, 11:41 AM
Sorted http://machsupport.com/forum/Smileys/default/smiley.gif

These switches cannot be used for combined homing/limits - the flickering output immediately triggers a limit fault after homing as it sees the flicker as the next sense input. Probably just crap sensors.

My fix was to use them for homing only, then add soft limits to control the position limits on all axes - the mill will always be homed when in use so this seems a safe option.

However, as the sensors all use one input, it sees the flickering as the next axis sense and just zeros all the dro's - did i say these sensors are crap?

The fix - modify the home-all button script to something like this for all axes...

DoButton( 24 )
While IsMoving()
Wend
DoOEMButton(133)
While IsMoving()
Wend
Code "G53 G1 z-3 F500"
While IsMoving()
Wend

This runs the home, zero's the DRO, then steps back 3mm which is enough to get the target clear of the sensors, then it moves onto the next axis and so on. It works perfectly but does leave the tool at X3, Y3, Z-3 but then you can jog back if it matters as the soft limits will stop a crash. It does NOT work without the While IsMoving lines in there. Debounce does NOT make any difference and is now set to zero.

I guess I could add a move to zero on all axes after the homing finishes, just to park it all at zero.

A video of homing working nicely...
https://youtu.be/T2CeluqhRl4

Now i can start final wiring and finish the build, damn good fun playing with it though

Clive S
13-03-2016, 11:49 AM
These switches cannot be used for combined homing/limits I don't think it is right to condemn the switches and say they don't work for combined use. Lots of people use them it all depends how they are wired. NPN and PNP are different and have to be wired different.

JAZZCNC
13-03-2016, 12:04 PM
Dave these switches 100% do work for both I use them all the time. It's either your using them wrong or possible the BOB doesn't work like you think.?

How you have worked around the problem may well work but I wouldn't trust for repeatabilty.

I think the answer to the problem is you'll need to use 10k resistor to force the input high.

Davek0974
13-03-2016, 01:09 PM
ok, but the inputs are already pulled high internally by 4k7 so surely another pull-up would be bad??

You can see the LED on the sensor flickering unless the tip is 100% covered by the target, this does not match my previous experience of inductive sensors where they are either on or off - NO flickering!

This is not a PNP/NPN issue, these are NPN and wired for NPN normally open.

JAZZ, you use sensors, does the LED flicker?

here's a video...
https://youtu.be/S5PP5sQh5Vk

Davek0974
13-03-2016, 01:21 PM
I don't think it is right to condemn the switches and say they don't work for combined use. Lots of people use them it all depends how they are wired. NPN and PNP are different and have to be wired different.

I didn't mean "these" as in all sensors, just maybe these super cheap eBay ones possibly, they were only 2.50ea. Previous experience was that the LED & output was either ON or OFF, not flickering depending on how close the target is.

JAZZCNC
13-03-2016, 01:27 PM
Even the super cheap Ebay ones work ok dave.

You haven't wired the switch powers in series have you.? That flickering looks like struggling for volts.!

Davek0974
13-03-2016, 01:30 PM
Even the super cheap Ebay ones work ok dave.

You haven't wired the switch powers in series have you.? That flickering looks like struggling for volts.!

Hi

No, all wired in parallel as described in manual, I have a quality bench psu and will test them on that now...

If you fully cover the end with the target the LED is solid on, but mach picks up the very first flicker and takes that as the position, as expected.

Maybe these are fakes or junk clones which have the output conditioning circuit missing??

JAZZCNC
13-03-2016, 01:36 PM
Nah I'd be suspecting the conflict between swithc and BOB my self. The input isn't conditioned correctly. Stick a 10K resistor on between 12v and pin 10.
Worst case is it will slow down the input reaction time.

I've had this before with prox switches and PMDX board using ESS.

Davek0974
13-03-2016, 02:27 PM
Thanks Jazz, I have some updates..

This seems to be a PSU issue believe it or not!

The BOB is powered from a little 15v SMPS, the sensors are powered from the BOB which has a DC-DC converter and puts out 12v.

First test was to put a sensor on my variable bench PSU, they worked perfectly! Clean on and off LED - perfect.

So i tried running the sensors direct from the 15v PSU - these are NPN so supply voltage does not affect the output signal and the 0v in/out is common on the BOB - result was that it worked ok UNTIL I took Mach out of reset when the flickering returned - baffled!

Next i tried running the BOB from the bench PSU - perfect result and i could even enable the limits (on one axis anyway) and it all worked as I first expected it should.

So - do we have a duff PSU, are these sensors sensitive to SMPS output?
I am not sure what to try now - baffled.

Maybe add some uF to the output of the supply and maybe some filtering?
I might get the 'scope out and see whats on the supply.

Get a different PSU? (this one came from CNC4YOU as did the BOB)

Here's another oddity - the plasma always wipes out the radio as soon as the drives are enabled, now it seems this build does the same - as soon as the drives kick in, the radio gets washed out.

Both builds use SMPS and all parts came from CNC4YOU. Food for thought.

Clive S
13-03-2016, 02:39 PM
I didn't mean "these" as in all sensors, just maybe these super cheap eBay ones possibly, they were only 2.50ea. Previous experience was that the LED & output was either ON or OFF, not flickering depending on how close the target is.You got robbed you can buy them for about 1.30 on ebay. I think you might be correct with the pull ups in that case I think you will need PNP sensors. But that doesn't mean they are crap.

JAZZCNC
13-03-2016, 02:41 PM
Here's another oddity - the plasma always wipes out the radio as soon as the drives are enabled, now it seems this build does the same - as soon as the drives kick in, the radio gets washed out.

Both builds use SMPS and all parts came from CNC4YOU. Food for thought.

Hence why I won't use SMPS(switch mode power supply for those wondering.!) on any drives. The fact you have probelms with one on the BOB doesn't inspire confidense in the BOB for me. It's needs should be simple and only be pulling milli amps so not taxng to any psu.!

JAZZCNC
13-03-2016, 02:45 PM
So - do we have a duff PSU, are these sensors sensitive to SMPS output?
I am not sure what to try now - baffled.

To answer this question then NO they usually work fine with SMPS. That's what I use for 24v circuit. Try a different PSU

Davek0974
13-03-2016, 02:46 PM
I need to narrow things down a little - is it the drive PSU upsetting the BOB or is it the BOB PSU ?

The BOB pulls 150mA including the three sensors.

Will be back soon with some results, the BIG worrying me is the radio interference - the plasma is fully grounded etc and works perfectly BUT it pumps out RF like billy!

Maybe I need to ditch the SMPS's and go linear.

Off for some tests.....

routercnc
13-03-2016, 02:55 PM
Hi Dave,

Going back to your first motion videos it looks like the X bearings could come off the ends of the rail as there is no hard end stop. Does something on the ballscrew contact first to prevent this?

Davek0974
13-03-2016, 03:34 PM
Hi Dave,

Going back to your first motion videos it looks like the X bearings could come off the ends of the rail as there is no hard end stop. Does something on the ballscrew contact first to prevent this?

Hi, yes at present they can easily come off, and have done ;)
No balls were lost though, luckily.

Davek0974
13-03-2016, 03:41 PM
Well, I am just about ready to give up for the day! And I hate shutting up shop on a negative position. :(

It works fine if i run off the variable bench PSU but not on the little SMPS, but i don't think it's needed to spend 110 on a PSU just for the BOB!

Here's a video showing the result on the SMPS...
https://youtu.be/m9_6XrzW0Fc

And here's one showing what I expected and indeed what I get on the bench PSU...
https://youtu.be/XcI2J5RcyrE

Now the big question is WHAT DO I DO??

Obviously I will be throwing this at CNC4YOU as it's all their components but they usually blame the setup or the earthing or the wiring blah, blah, blah...

Facts...

The drive PSU & drives wipe out FM radio when engaged.
The BOB PSU does not work with my sensors.
The sensors appear fine when on a different PSU.
I am a bit p1ssed off at present as this little setup should have been easy ;)

Just about ready to pour a big one.

JAZZCNC
13-03-2016, 03:56 PM
Well look at it has good result it's just not the one you wanted.!! . . Good because you know the cause and not ending not knowing the reason.

The fact the bob works with bench supply shows it's working so PSU would be my first choice.

The drives affecting radio is a little concerning because shows dirty system (or Crap drives) so i'd be looking at this while i'm at it. Personanly it's no brainer to me I'd dump the SMPS and go with toroidal setup. 15mins work to man of your calibre.!!

Davek0974
13-03-2016, 04:06 PM
Thanks Jazz,

Is there a preferred circuit or supplier of parts for a suitable linear supply?
Need 48v at up to 10A.

Keep the BOB on the SMPS?

The radio interference has been nagging me since i got the plasma going - same drives, motors and PSU again, no help at all from CNC4YOU of course.

I always use shielded motor cables, grounded at the drive end, and even used shielded wire for the step/dir signals on the plasma.

No objections to building a psu but cant risk over-volting the drives by building it wrong, they are ok up to 50v

Thanks

JAZZCNC
13-03-2016, 05:03 PM
Plasma by it's nature is dirty business so no surprise when that fires up but drives them selfs shouldn't be messing with radio.

So many things could be in play here like you know but I'd certainly start by getting rid of the SMPS for the drives. Nothing to them really just toroidal transformer Caps and bridge rectifier.

Size wise then it gets tricky with 50v because standard transformers either compute very close to 50vdc or just a little lower than needed.
The transformer I would use is this one with 2 x 33Vac secondery's giving 300va because. While it's less than 48vdc it's safer than next option which would close to 50vdc.

Normally I'd wire secondery coils in series which adds the volts together but keeps the amps same and use lower voltage seconderys. But in this case the nearist available which is 2 x 15Vac computes to low Ending up around 40Vdc after being recified.
Next option is 2 x 18Vac which takes too close to 50vdc.

So in this case going with 2 x 33Vac and wiring in parallel will give around 44Vdc and add the amps together giving 9A. This is much safer option and won't cost any performance. The way Toridal works then 9A is more than enough for 4 drives.

This one.
http://www.airlinktransformers.com/chassis_mounting_toroidal_transformers/chassis_mounting_toroidal_transformers_standard_ra nge/CM0300233/

Then you'll need 3 x Caps around 4700uf 63v wired in parallel these will do nicely
http://www.ebay.co.uk/itm/4700uF-63V-85oC-Snap-in-electrolytic-capacitors-Qty-6-NEW-SPECIAL-OFFER-/111907866124

Then 25A bridge and your sorted.
http://www.ebay.co.uk/itm/KBPC2502-25A-Bridge-Rectifier-200V-/121411255908?hash=item1c44acbe64:g:u7oAAOSwDk5T7gh A

Davek0974
13-03-2016, 05:14 PM
Thanks Jazz,

I was leaning towards 30v secondary but that one does fit well, have got caps and bridge so the transformer is on order now.

If that works I'll ditch the PSU in the plasma too - note that it's not the PLASMA that kills the radio, it's the CNC drives again, as soon as i take Mach out of reset.

Hopefully this will move us along again, fingers crossed.

Davek0974
14-03-2016, 03:21 PM
Had a reply from CNC4YOU, they have tested all their stock of the SMPS i have and found 1 that has the same issue - at least I am not going mad.

They are sending out a replacement unit, 24v this time.

I have also borrowed enough bits to cobble together a 36v linear supply, if the new SMPS fails to sort the issue, I have that option ready to try.

Also ordered parts to make a full-power linear supply.

The radio interference is a false lead i think - i borrowed a FM/DAB portable last night and the signal is so weak in the shop that DAB was 100% dead and FM only just worked on Radio2 (which is all i use really, never bothered trying other stations so did not notice the massive lack of signal) So it may possibly be just caused by a very weak reception area. I'm ignoring this issue for now.

Davek0974
15-03-2016, 07:29 PM
Well, I'm officially baffled but very happy!

Changing the BOB PSU has completely fixed the issue, I have now got sensible homing routine, all limits working and the homing accuracy is now better than 0.1mm, more like 0.00 to -0.06mm variation over 25 homing calls.

Happy days :)

Davek0974
17-03-2016, 01:49 PM
Now, the question is,,,,

Having bought all the parts to make a linear PSU, is it worth fitting it or should I leave it as-is??

JAZZCNC
17-03-2016, 05:29 PM
Now, the question is,,,,

Having bought all the parts to make a linear PSU, is it worth fitting it or should I leave it as-is??

If it aint broke don't mess. Just keep it on stand by.!

Out of interest have you tried this on Plasma to see if it stops that.?

Davek0974
17-03-2016, 08:17 PM
No, i'm not tempting fate, don't want to risk upsetting her ;)

Davek0974
18-03-2016, 04:57 PM
Things are progressing...

17959

Leaving it on the little bench i made to build it, fits well and the electrics will fit underneath nicely.

Since the picture was taken I have fully wired the panel and tested the safety circuit etc, this is now in the cabinet and waiting connection. The VFD is mounted behind the cabinet so i can see it from under the table, this keeps it safe from flying chips etc and away from the drive electronics.

I have the E-stop circuit controlling the VFD and cooling pump supplies, it also has a connection to the BOB to tell Mach3 that it's in E-Stop, this circuit also functions as a No-Volt-Release system to stop the spindle restarting after a power loss.

The pump supply and misting system solenoid is controlled from a relay board driven by the VFD internal relay so they come on and off as the VFD does, the misting supply also has a front panel switch so i can leave it off when cutting wood etc.

Tomorrow will be wiring, testing and making the bed and fitting it hopefully.

:subdued:

Davek0974
19-03-2016, 03:21 PM
Well, she survived the rewire and panel fitting, also got the VFD fitted and spindle running under 0-10v and stop/start from the BOB. Surprised how quiet the motor is.

Installed the new screen-set (2010) and got that going, looks nice. Tweaked the homing speed and at 15% the homing accuracy is now +0 to -0.02mm which is far better and will leave it there for now.

Questions ---

Touch plate -
to make this work i need to connect the probe input to ground via my tool, I presume it is OK to connect the BOB 0v line to machine chassis in order to make this work with only one probe wire??

Spinde Stop -
Do we use coast-to-stop or ramp-to-stop??

Spindle acceleration -
What sort of spin-up setting is good in the VFD?
I presume this also goes in Mach3 Spindle delays?

Got to finish my bed plate now...

Davek0974
19-03-2016, 05:01 PM
Thats enough for one day ;)

Got the main bed plate on, aluminium top-bed needs to be drilled and tapped for hold-downs etc, thats tomorrows job.

17967

Coming along :)

JAZZCNC
19-03-2016, 07:40 PM
Coming along nice Dave.:thumsup:



Touch plate -
to make this work i need to connect the probe input to ground via my tool, I presume it is OK to connect the BOB 0v line to machine chassis in order to make this work with only one probe wire??

Yes can do it that way thou need to be careful and check the probe by touching tool every time just in case tool doesn't conduct very well ie: coated etc.
IT's good habbit to get into.


Spinde Stop -
Do we use coast-to-stop or ramp-to-stop??

Little bit of DC braking won't hurt but not too much else trip VFD with large tools.


Spindle acceleration -
What sort of spin-up setting is good in the VFD?
I presume this also goes in Mach3 Spindle delays?

I have mine set to 2 or 3 secs and spindle delay set to 2. Again if spindle startup too fast you'll get vfd throwing up error codes.
Mach delay needs to be about the same delay.

Davek0974
19-03-2016, 10:47 PM
Thanks Jazz,

Will set those tomorrow.

I might have to re-visit my linear rail parallel setting - something appears to have moved slightly during build as the top-right corner of my bed seems about 0.3mm high compared to the other three which are relatively true. As you can see in the pic, I have mounted a DTI on my spindle clamp and was measuring the bed while jogging around.

Its a bit of a pain as it means almost full strip-down, not sure i can shim the bed that much to get it happy, will have another look tomorrow.

Davek0974
20-03-2016, 04:58 PM
She's done! (well just about :congratulatory: )


This was encouraging - A 300mm square placed on the bed and against the face of the Z axis tool mount - perfectly square, I was impressed with this little fact :wink:
17969

The fixed tool-change plate for the 2010 screen-set was hastily made up from a length of nylon with an M8 bolt in the top that had the face ground flat, it lives in the top R/H corner of my bed.

The movable plate was a simple bit of unused copper PCB.

The tool change and probing routine took a bit of getting used to, as will the initial set-up for new materials etc, its all totally alien form my experience in plasma cutting, lots to learn.

A lump of junk alu was then clamped down with overkill clamps and a further half an hour expended trying to figure out the correct probing routine for a new job :cool:

The G-code i prepared was too big for the scrap so thats why it got cut off, I was running out of time :)

I used the WD40 in one hand and the blow gun in the other, a pretty intense minute or so followed as she cut her first metal.

17970

Messy or what ?

Anyway, the result was excellent, expecting a broken tool I threw in an older 5mm HSS three-flute and tweaked the g-code down from carbide speeds, this ended up at 12000rpm and 800mm/min cut with 500mm/min ramp. Ramped in to 3mm deep on the pocket and 5mm deep on the outside.

I'm pretty stoked at the result, a simple feat but nerve-wrecking when not used a CNC before, coming from manual milling it feels odd having the control of feed and speed taken away from you!

BTW, I removed the bed and refitted it, with minor shimming I got the variation corner-corner down to below 0.1mm which i think bearing in mind the way these machines are constructed is pretty good.

Now I need to build the fogless coolant thingy and get that going before doing some proper tests.

JAZZCNC
21-03-2016, 01:38 PM
Looking good dave and nice to see a proper Chip not dust. . :applause:

Davek0974
21-03-2016, 01:44 PM
I don't baby my tools, causes more trouble than needed, need a good chip to carry the heat away.

As the scrap was smaller than the code, it ramped down mostly in air and slammed into the side of the part at full depth, didn't bother it all :)

It was a tense moment though I must admit ;)

Need to get the lube system working now, got a couple of jobs lined up already.
Maybe add some chip-guards as well to keep the crud on the table and not all up the wall.

Ger21
21-03-2016, 03:46 PM
I'm pretty stoked at the result, a simple feat but nerve-wrecking when not used a CNC before, coming from manual milling it feels odd having the control of feed and speed taken away from you!

You still have control with the override sliders. Just grab the orange bars and drag them up or down, or type in a specific amount.

Davek0974
21-03-2016, 03:49 PM
LOL, it was a fast test job, by the time I had reached for the mouse, grabbed a slider and hopefully yanked it in the right direction, the job was done and the tool was off and parked ;)

It's a lot slower than brain telling hands - "stop twiddling that feed knob you idiot, the cutter is gumming up"

Just need to get used to it.

Davek0974
02-08-2016, 08:11 PM
Machines been working well generally, only major issue is random VFD drop-outs with an error code that indicates a short in the motor windings?

Its not done that much work really, i cant believe the spindle is dying already?

The MAJOR issue with this issue is that i haven't wired the VFD fault signal into Mach3 yet so the spindle cuts out and *ping* goes another cutter :(

I need to drag the diagrams out and figure a way to get the fault into Mach, at least that will save my cutters, but surely not the spindle already - this was from Aliexpress, any warranty do you think??

Is there a "good" spindle to replace it with?

JAZZCNC
02-08-2016, 10:07 PM
Nah doubt it's spindle Dave I'd think it's more like setting that needs tweaking.

Davek0974
02-08-2016, 10:18 PM
Main concern was the error code pointing towards motor phase short, not current overload etc, I'll check the manual but i don't think the short setting would be adjustable?

Clive S
02-08-2016, 11:28 PM
Main concern was the error code pointing towards motor phase short, not current overload etc, I'll check the manual but i don't think the short setting would be adjustable?Might be a long shot but have you checked the motor connections at both ends

Davek0974
03-08-2016, 08:14 AM
Not yet but will pull it apart this weekend.

Davek0974
22-08-2016, 02:47 PM
Been working well, last week did a 5 hour run of parts :)

Today i had one part and the blasted spindle cut out 4 times on me, luckily as i don't trust it i was close enough to e-stop each time and save my cutter.

I can't see any loose wires and its the same vfd message each time :(

Not sure what i can check really?

Davek0974
22-08-2016, 07:44 PM
Ok, pulled it apart and rewired the VFD relay into Mach3, if it faults now it will throw the Cycle-Stop button so at least that will save any more busted tooling.

Not sure what the real cause of the drop-outs is but at least i can walk away from it now.

Davek0974
30-08-2016, 02:24 PM
So far so good - no faults since wiring changes :)

Did have a probing error though - setting up for engraving plastic, 0.2mm 30deg 3mm tool in, tested the touch-plate as i always do, pressed the Z-Ref button, tool comes down and just keeps on going - pushed that little carbide bit through the pcb touch-plate, through 3mm of engraving plastic and a couple of mm into the machine bed :(

By the time i had hit the e-stop, the stepper was stalling, no idea why, i rebooted and it was ok for the rest of the day.

Scary stuff.

njhussey
30-08-2016, 02:36 PM
Did have a probing error though - setting up for engraving plastic, 0.2mm 30deg 3mm tool in, tested the touch-plate as i always do, pressed the Z-Ref button, tool comes down and just keeps on going - pushed that little carbide bit through the pcb touch-plate, through 3mm of engraving plastic and a couple of mm into the machine bed :(

By the time i had hit the e-stop, the stepper was stalling, no idea why, i rebooted and it was ok for the rest of the day.

Scary stuff.

Dave, I had the same thing happen to my touch plate, it's got a 3.175mm hole punched through it, the 18mm MDf base and into the Ali bed....mine was because the earth wire had become unattached. Just goes to show how much power these things have, wouldn't want my fingers (or anything else) in the way of it! Needless to say I watch the procedure like a hawk now with one hand on the 'o'shit button...just in case!

Davek0974
30-08-2016, 02:43 PM
Yep thats the stance i adopt now - one hand on the plate the other over the red button!

This was on the little stepper machine, on the Bridgeport with its AC servo drive i think things would have been far worse as they just do not stop until things break.

Clive S
30-08-2016, 08:16 PM
Did have a probing error though I have had a similar problem and not got to the bottom of it I am now thinking that you should put a crock clip on the tool to ground as you probe because you are relying on the bearings in the spindle. It just does it very occasionally.

Davek0974
30-08-2016, 08:24 PM
Thats a possible reason there, thanks. It also could be a bit of crap under the tool maybe - this was a tiny tool with a 0.2mm tip so not a lot of contact area.

It would mean carnage if it happened on the Bridgeport though, I am not using probing on the main spindle as have now sorted out fixed-height tooling etc, but when i have the engraving spindle fitted i will need to use it then as the spindle only has Er20 collet.

njhussey
30-08-2016, 11:41 PM
I always touch the touchplate to the tool before doing the probing now, just to make sure!

Sent from my HUAWEI VNS-L31 using Tapatalk

Davek0974
31-08-2016, 08:08 AM
I always touch the touchplate to the tool before doing the probing now, just to make sure!

Sent from my HUAWEI VNS-L31 using Tapatalk

Ah, but so do i - the LED lit up when i did the test but the routine still did not stop when i did the probe.

njhussey
31-08-2016, 09:39 AM
Ah, but so do i - the LED lit up when i did the test but the routine still did not stop when i did the probe.

Bugger!!

Davek0974
31-08-2016, 09:58 AM
Yep, thats pretty much what i thought while i watched my new cutter get buried in the bed :)

I have a little less trust for it now but thats probably not a bad thing.

Clive S
31-08-2016, 06:28 PM
OK I have mine sorted I use a Purelogic board for the router but I have a simple bob tagged off it for the probe this had 5V inputs pulled high. I had put a resistor in series with the input pin sometime ago and I had forgot about it. I measured the voltage on the probe plate, It was only about 3.3V so there was my problem it was just on the edge of working when I removed the resistor it measured 5V. Problem solved for me anyway.