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h4ppy-chris
21-12-2010, 08:15 PM
my first cnc project from the start. as i type i am formating a pc that will be dedicated just to cnc.
my board came today from ebay :smile: very fast delivery 2 days.
i will post more as i get on.

3498

3499

irving2008
21-12-2010, 09:07 PM
Ah, the ubiquitous TB6560 3-axis board from eBay... If you haven't already, you might want to search for TB6560 and look at other threads related to these boards...

h4ppy-chris
21-12-2010, 09:53 PM
Ah, the ubiquitous TB6560 3-axis board from eBay... If you haven't already, you might want to search for TB6560 and look at other threads related to these boards...

i have but pressed the buy it now!! i hope it gives me some probs so i can help others :)

h4ppy-chris
23-12-2010, 07:18 PM
well got the pc up and running and the steppers all wired up plugged in and running :smile:
no probs as yet :smile:


http://www.youtube.com/watch?v=rTwB0BJCjt0

FatFreddie
23-12-2010, 07:30 PM
The motors make useful hand warmers this time of year :-)

Mine run on the edge of too hot to touch and I haven't had any problems yet - 80 degrees C above ambient seems a common maximum.

blackburn mark
23-12-2010, 07:41 PM
hahahah!!! nice one chris... its ages since i was in that position watching them motors turn on the road runner g-code
it was all magical mystical shit to me (still is a bit)
iv got the 5 axis version of your board, my motors are a bit bigger than yours and dont really get hot at all on 24v, iv heard plenty of people reporting how hot the motors get, i think in some cases its pretty normal

irving2008
23-12-2010, 07:46 PM
What motors are those Chris?

irving2008
23-12-2010, 07:52 PM
The motors make useful hand warmers this time of year :-)

Mine run on the edge of too hot to touch and I haven't had any problems yet - 80 degrees C above ambient seems a common maximum.

I hope not... 85degC absolute case temp is the maximum recommended temp you should run a stepper at - higher than that and you risk internal breakdown and demagnetisation.... remember inside its going to be a lot hotter!

an 85degC case is too hot to touch for most people. Maplin do a cheap 19 multimeter with a temp probe (http://www.maplin.co.uk/Module.aspx?ModuleNo=48318&&source=14&doy=search) thats a useful bit of kit for playing with electrics...

h4ppy-chris
23-12-2010, 08:41 PM
What motors are those Chris?



Bipolar NEMA 23 case size. Rated current 1.2A, holding torque 0.314Nm(3.2kg-cm). Rotor inertia
0.55kg-cm2. Detent torque 0.0492Nm(500g-cm). 4-connections flying lead 115mm long terminated with a .1"
pitch SIL header type socket. Output shaft 6.3mm dia x 19mm long. Body 56.5mm dia x 40mm long with 57mm
square mounting face haveing a 5.2mm dia mounting hole in each corner on an approx 47mm square.

irving2008
23-12-2010, 10:26 PM
Chris... just what do you plan to do with those motors?

h4ppy-chris
24-12-2010, 04:15 PM
nothing atm irving i think my 1st thing i will do is convert my milling mc to cnc :)

irving2008
24-12-2010, 06:21 PM
oh right, just those are very lightweight motors and I was wondering about your expectations of them...

FatFreddie
24-12-2010, 07:43 PM
I hope not... 85degC absolute case temp is the maximum recommended temp you should run a stepper at - higher than that and you risk internal breakdown and demagnetisation.... remember inside its going to be a lot hotter!

an 85degC case is too hot to touch for most people. Maplin do a cheap 19 multimeter with a temp probe (http://www.maplin.co.uk/Module.aspx?ModuleNo=48318&&source=14&doy=search) thats a useful bit of kit for playing with electrics...

Sorry, yes - 130 degrees max internal which is about 85 degrees on the case. This website (http://www.sxdjzz.com/NewShow.aspx?id=3,2) seems to think 70-80 degrees is normal - bit of a useless temperature that - hot enough to want to avoid touching but not hot enough to make tea.

80 degrees above ambient is pretty tepid in my garage at the moment so I don't think it will be a problem for a while :-)

h4ppy-chris
26-12-2010, 01:03 PM
well i tested the temperature 54c
3513
my 24v supply turned up :smile:
when its all running should it sound like 56k modem?
can any one recommend a program to start with for gcode.

Jonathan
26-12-2010, 01:03 PM
Sorry, yes - 130 degrees max internal which is about 85 degrees on the case. This website (http://www.sxdjzz.com/NewShow.aspx?id=3,2) seems to think 70-80 degrees is normal - bit of a useless temperature that - hot enough to want to avoid touching but not hot enough to make tea.

Hot enough if you're 6700m above sea level!

My motors (3nm size 23, 4.2A on 75v) rarely got hot. The vast majority of the time I can barely feel any temperature rise. It's only when the machine has been running for a long time that they start to get hot. I think the drivers reducing the current to 50% when stationary helps here.
It makes me wonder if I can up the current a bit and get a bit more torque/speed. It's on 4.09A, could try 4.64A. That'd be up to 30% more heat I think (I^2*R), or 20% above rated power.

Jonathan
26-12-2010, 01:06 PM
when its all running should it sound like 56k modem?


Yes, mine does too. Could get it to play a tune if you tried...know the frequency from the step rate. Got three 'instruments' (motors) so could even do some interesting harmony...

M250cnc
26-12-2010, 01:16 PM
Could get it to play a tune if you tried...know the frequency from the step rate. Got three 'instruments' (motors) so could even do some interesting harmony...

There have been some Christmas tunes on the zone in the past.

Phil


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h4ppy-chris
28-12-2010, 03:14 PM
what motors should i be looking for? the board i bought is the 2.5amp and 24v PSU.

Jonathan
28-12-2010, 03:23 PM
what motors should i be looking for? the board i bought is the 2.5amp and 24v PSU.

Depends greatly on the size of your machine, are you using ballscrews/ACME etc. With only 24v you want a motor with very low inductance to get any reasonable speed.
reccomended v=32*L^0.5, so rearranging that:
L=(24/32)^2=0.56mH
So your looking for a motor with an inductance ideally lower than 0.56mH, and sufficient torque...you'll be lucky to meet those criteria so just find as close as possible.

Hope that helps...

h4ppy-chris
28-12-2010, 04:07 PM
sort of helps, from this which would you say is the best to go for?


http://www.savebase.com/InfoBase/SAVEBASE/PKG/001521/Image/nema23_56.png

h4ppy-chris
28-12-2010, 04:22 PM
this is my MC that i want to convert to cnc

3514

blackburn mark
28-12-2010, 04:26 PM
iv got the 5 axis version of your board and im using 57BYGH76-401A steppers (at the bottom of your posted table)
im pretty happy with them at the mo
i get 1500mm/min on a pretty heavy gantry
nowhere near as fast as jonathans but good enough for the price :)

blackburn mark
28-12-2010, 04:32 PM
this is my MC that i want to convert to cnc

not sure youll get 1500mm/min pushing that back n forth
im guessing you will have to use belts and pullies to up the torque

Jonathan
28-12-2010, 04:32 PM
Out of those motors I'd go for the last one, with the biggest torque. Except your driver is only 2.5A...I think that's near enough though. Definitely get a 4 (or 8) lead motor. Your milling machine is very similar to mine and I found that when I started with 1nm motors they just didn't have enough torque to go above a few mm/s and required pulley reduction, so I upgraded to 3nm motors from Zapp, with their 70v drivers which works very well.

By all means try using the driver you've got, it'll work and if you don't mind it being a bit slow that's fine. I do advise getting quite big nema23 motors though. They'll serve you well if you get a better driver.

h4ppy-chris
28-12-2010, 04:33 PM
will they be ok with my 2.5 amp board or should i get the 3 amp board?


iv got the 5 axis version of your board and im using 57BYGH76-401A steppers (at the bottom of your posted table)
im pretty happy with them at the mo
i get 1500mm/min on a pretty heavy gantry
nowhere near as fast as jonathans but good enough for the price :)

Jonathan
28-12-2010, 04:34 PM
i get 1500mm/min on a pretty heavy gantry
nowhere near as fast as jonathans but good enough for the price :)

The difference here, in addition to mass, is you have nice linear bearings, not a heavy dovetail with lots of friction.

Jonathan
28-12-2010, 04:42 PM
will they be ok with my 2.5 amp board or should i get the 3 amp board?

They would work on 2.5A, just with slightly less torque.

h4ppy-chris
28-12-2010, 04:56 PM
thanks alot guys for your help :)

irving2008
28-12-2010, 05:56 PM
Chris,

Have a look at the tutorial I wrote here (http://www.mycncuk.com/forums/showthread.php/1524-What-size-stepper-motor-do-I-need.)... will give you some insight into your needs.... you have to start with what you are trying to move... then decide how fast you want to move it and how you are going to move it... that tells you what you need to move it with... and then you can decide what motor/driver package will work...

BTW what mill is that? looks similar to my Warco, but older...

h4ppy-chris
28-12-2010, 06:27 PM
thanks irving had a look at your tutorial it was a very good read.
am not sure of the make of the mill no markings on it :( but would love to know.

M250cnc
28-12-2010, 06:30 PM
The difference here, in addition to mass, is you have nice linear bearings, not a heavy dovetail with lots of friction.

Jonathan is quite correct about friction, a really important mod is a one shot oil system. This will reduce the wear and reduce the friction its the only way to get the lube in just where its needed, just a PITA to do.

Phil

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M250cnc
28-12-2010, 06:50 PM
thanks irving had a look at your tutorial it was a very good read.
am not sure of the make of the mill no markings on it :( but would love to know.

I have a similar mill,i have 70v ps running at 6 amps rapids at 2000 mm pm motors are 4Nm I would say that to be the minimum spec.

Increasing the power via belts will also reduce the max speed unfortunately speed costs money.

Phil

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irving2008
28-12-2010, 07:57 PM
Well, having done the calcs on my mill, and measured the actual friction coefficient with a digital spring gauge, I know the likely motor is going to be in the order of 3Nm to achieve 1300mm/min cutting and 2500mm/min rapids. If I hadn't measured it then the estimated friction coeff of 1.1 would have suggested a 4Nm motor. I'm working on 36v @ 4A as I have a 36v, 12A PSU to hand.

The point here is that every mill is different. You need to weigh the table and measure the friction coefficients to avoid overegging the solution. I am not fussed about cutting speeds as long as they are reasonable... its still going to be faster/more accurate than I can do it by hand and since I dont have suds or one-shot oilers I'm going to have to be there to spray/oil as it runs.... Its not going to be working hard enough to justify doing those mods...yet...

Jonathan
28-12-2010, 09:30 PM
I know the likely motor is going to be in the order of 3Nm to achieve 1300mm/min cutting and 2500mm/min rapids...

Those numbers are similar to what I got on my milling machine with the same motor. I've never cut at over 1000mm/min, and that was with a big cutter (http://www.youtube.com/watch?v=iC7lXNTPYrg&feature=mfu_in_order&list=UL). The 2150rpm spindle limits the feedrates I can use. I started off with 2500 on the X axis (see http://www.mycncuk.com/forums/showthread.php/1904-Are-the-Zapp-3NM-steppers-good-with-their-PM-752-drivers?p=12790&viewfull=1#post12790 post #19), but have gradually reduced that to 1800 over time. Now I've taken the motors off to use them on the router. It will still do more than 1800, but not 2500...I think the ACME screw or something has worn a fair bit. Time for ballscrews perhaps-that should make it a bit faster due to the efficiency.

3516

irving2008
28-12-2010, 09:59 PM
Looks like a Clarke MD25 - Similar to the Warco MD30/Minor i have.... tho mine has a longer table... I wont be using the original screws but some ballscrews I got off Robin..... the top speed of the spindle is limiting, I have a VFD to go on so plan to increase the belt ratio to up it to 3000 or so... tho running at 1800mm/sec with a 6mm cutter would ideally like 5000rpm on the spindle... not sure the bearings will like that much tho...

Jonathan
28-12-2010, 10:28 PM
Looks like a Clarke MD25 - Similar to the Warco MD30/Minor i have.... tho mine has a longer table...... tho running at 1800mm/sec with a 6mm cutter would ideally like 5000rpm on the spindle... not sure the bearings will like that much tho...

If that's mine your referring to then it's a Clarke CMD1225C from Chronos (though I got it second hand). The castings look pretty much the same. Agreed with the 5000rpm. I'm thinking either mount a separate spindle to the side of the main one (i.e. my 6000rpm 6kw-ish brushless motor), or put that same motor in place of the 750w original motor. I was about to ask you if you thought the bearings would take that rpm! They allready sound a bit rattly and the spindle pulley gets warm - maybe that's normal. How long is your table and what are the travels just out of interest? I get 350x141x92mm.

What diameter are your ballscrews?

irving2008
28-12-2010, 10:44 PM
The table on the MD30 is 675 x 205mm approx and the travels are 490 x 195 x 105mm approx. The ballscrews are 16mm dia. I'm pretty sure my quill bearings won't like 5000rpm, they get warm on 2150! I was considering a secondary spindle based on an ER collet chuck, belt driven 1:2 or 1:3 off the main one, similar to what Robin's done (but probably nowhere near as neat :lol:).

M250cnc
28-12-2010, 10:53 PM
I have a VFD to go on so plan to increase the belt ratio to up it to 3000 or so... tho running at 1800mm/sec with a 6mm cutter would ideally like 5000rpm on the spindle... not sure the bearings will like that much tho...

Can you not up the frequency instead ?

I renewed my bearings with SKF they are rated at 7K

I have run mine at 3.5K but I need to change the belts as I have the twist lok type and you can see the effect of centrifugal force. Scary

I do intend to go to 5K

Phil


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irving2008
28-12-2010, 11:11 PM
i have some worn A-belting... its starting to fray :lol: yes I can take the motor higher on the VFD but not from 2150 -> 5000 using the same pulley set. You can over rev the motor maybe 10 - 15% say 2500, but what I plan to do is put a new small fixed pulley on the motor and run a single belt (with an idler to get round the column) using the largest pulley on the spindle.

M250cnc
28-12-2010, 11:24 PM
Irving I am gonna have to disagree.

My motor speed is 1400 and as you know they also come in speeds of 2800 so it depends on the stock speed

I have run it at 100Hz for long periods the motor does not get warm in the slightest.

Who told me I could do that, the company who sold the motor inverter package to me.

The motor upgrade was forced on me due to the fact that the original motor over heated and was poorly balanced.

So it turned out a blessing in disguise.

Phil

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irving2008
28-12-2010, 11:37 PM
Ah yes...if you have a VFD/Inverter rated motor... mine is c1998 1.5kW (2hp) 3-phase 1400. it'll run ok at 1600-1700... i wouldnt like to take it to higher than that... so geared up 1:2 it'll give me 3000 - 3500 at the spindle...., maybe a tad more....

h4ppy-chris
30-12-2010, 01:27 AM
all that is some good info guys thanks for all of it :smile:

now i bought some ally plate today is it a good price?

80mm x 247mm x 12mm Aluminium Plate / Sheet 1 4.75 GBP 4.75 GBP
103mm x 227mm x 10mm Aluminium Plate / Sheet 1 4.95 GBP 4.95 GBP
125mm x 185mm x 10mm Aluminium Plate / Sheet 1 4.50 GBP 4.50 GBP
69mm x 481mm x 10mm Aluminium Plate / Sheet 1 6.50 GBP 6.50 GBP
110mm x 540mm x 6mm Aluminium Plate / Sheet 1 6.50 GBP 6.50 GBP

Subtotal: 27.20 GBP + 7.06 GBP Postage & Packing

i want to use it to mount the motors on.

irving2008
30-12-2010, 01:50 AM
I usually reckon anything better for Aluminum than about 7/kg is a good price... that first piece is 0.65kg, so 4.56 would be a good price... overall you got 3.82kg Aly for 27.20, my guide price would have been 26.77. You paid slightly over the odds on the smaller offcuts and did slightly better on the larger ones... overall, not bad.

h4ppy-chris
30-12-2010, 02:23 AM
cheers irving once again :) just wanted some ally to paly with an impulse buy :-)

Jonathan
30-12-2010, 12:28 PM
cheers irving once again :) just wanted some ally to paly with an impulse buy :-)

Where did you get it from?

h4ppy-chris
30-12-2010, 02:59 PM
ebay http://stores.ebay.co.uk/The-Bits-And-Pieces-Place
(If purchasing multiple Items request an invoice for combined shipping costs) i saved 12 ;-)


Where did you get it from?

h4ppy-chris
01-01-2011, 10:54 PM
brain has gone west, 3 holes centers at 35mm what is the circumference ?
help an how did you get the answer.

blackburn mark
01-01-2011, 11:25 PM
219.91148575128552669238503682957mm ish :)
2 x pi x r

unless iv got the wrong end of the stick

h4ppy-chris
01-01-2011, 11:42 PM
3 holes around a circle 35mm apart if that helps what is the circumference ?

Jonathan
01-01-2011, 11:47 PM
Erm, surely that's just 35*3 = 105mm? I've probably got a different end of the stick...

m_c
02-01-2011, 12:56 AM
I get a radius of 20.207.

I'd explain fully, but I'd need to do a drawing.
It involves the constant that all the angles within a triangle add up to 180deg, and a bit trigonometry.

blackburn mark
02-01-2011, 02:53 AM
ahh... i get it now, im with m_c on this one 20.07mm radius will intersect 3 points 35mm apart

took me ages to work that out

h4ppy-chris
02-01-2011, 11:03 AM
i can find the formula for 4,5,6 but not for 3 :confused:
3529
PCD Calculation Formula
3 stud PCD = S / 0.866
4 Stud PCD = S / 0.7071
5 Stud PCD = S / 0.5278
6 Stud PCD = S / 0.5

ptjw7uk
02-01-2011, 11:25 AM
3 stud PCD= S/0.866

peter

h4ppy-chris
02-01-2011, 11:30 AM
thanks peter star man, added it to the post :-)

Jonathan
02-01-2011, 12:07 PM
Ahh, now I understand the question! You wanted *diameter* not circumference at stated in your post.

It's just cos(30)...

Let x be side length of the triangle the three points form (i.e 35mm).

(see diagram)

Draw in lines on triangle that bisect the angles. So we've now got a smaller triangle with one side length x/2, and we know the angle indicated is 30 degrees, since it's an equilateral triangle and we've bisected the corner angle.

cos(30)=(X/2)/r
r=X/2/cos(30)
r=17.5/cos(30) = 20.2072594...
(since d=2r, d=X/cos(30))

Incidentally to help remember it cos(30) is just sqrt(3)/2 = 0.866025...
Hope that helps. You can get the other PCDs using similar methods. 4 is half root 2.

h4ppy-chris
02-01-2011, 12:18 PM
thanks jonathan ;-)

Jonathan
02-01-2011, 12:23 PM
Ahh just realised. My method can easily be extended to the general case for n bolts. You just need to know half the angle interior angle of the particular polygon. Then do cosine of that to get the factor...

3 = Triangle, 60/2 = 30, so cos(30)
4 = Square, 90/2 = 45, so cos(45)
5 = pentagon, 108/2 = 54, so cos(54) = 0.5878 (!)
6 = hexagon, 120/2 = 60, so cos(60) = 0.5

The formula to find the interior angle is 180(n-2)/n.
So that means, given n bolts with spacing x.

r=x/(cos(90(n-2)/n))
PCD = x/(2*cos(90(n-2)/n))

enjoy!

mmcp42
02-01-2011, 01:10 PM
like the formulae but...
er where is x used??

ptjw7uk
02-01-2011, 01:18 PM
x=bolt spacing(centre to centre)
Peter

mmcp42
02-01-2011, 01:39 PM
Ahh just realised. My method can easily be extended to the general case for n bolts. You just need to know half the angle interior angle of the particular polygon. Then do cosine of that to get the factor...

3 = Triangle, 60/2 = 30, so cos(30)
4 = Square, 90/2 = 45, so cos(45)
5 = pentagon, 108/2 = 54, so cos(54) = 0.5878 (!)
6 = hexagon, 120/2 = 60, so cos(60) = 0.5

The formula to find the interior angle is 180(n-2)/n.
So that means, given n bolts with spacing x.

r=cos(90(n-2)/n)
PCD = 2*cos(90(n-2)/n)

enjoy!

my question is - none of these formulae use x - I'm sure they should somewhere?!?

r= x/(cos(90(n-2)/n))
PCD = x/(2*cos(90(n-2)/n))

m_c
02-01-2011, 03:17 PM
should be x/cos(whatever), as you're working out the hypotenuse from the adjacent.

mmcp42
02-01-2011, 04:04 PM
fair do's
I've updated by guesswork...

Jonathan
02-01-2011, 04:47 PM
should be x/cos(whatever), as you're working out the hypotenuse from the adjacent.

Yes it is, sorry ... was rushing and missed that :redface:

h4ppy-chris
03-01-2011, 05:52 PM
big time backlash on the z axis so time to investigate and here's what i found.


http://www.youtube.com/watch?v=HhvexSsmMxk

and here's how i sorted it :smile: there was play between the bearings so skimmed 0.76mm of the end cap no more play :smile: backlash now down to 0.003

http://www.youtube.com/watch?v=I8_JhbRmj7Y

h4ppy-chris
08-01-2011, 03:25 PM
well my ally turned up so made a start on the z motor plate :smile:
all i could think of when making it was, if the mill was finished i would just be watching it being cut.


3552 3551

Jonathan
08-01-2011, 03:42 PM
well my ally turned up so made a start on the z motor plate :smile:
all i could think of when making it was, if the mill was finished i would just be watching it being cut.


3552 3551

Similar to how I did it except I mounted the motor plate 90 degrees clockwise to yours, and lathed a bit of 3" aluminum bar to act as a spacer and give a bit more surface area for the motor plate to bolt on to. Doing it that way enables me to use the handle for manual drilling without removing the stepper - I think yours would collide?

h4ppy-chris
08-01-2011, 04:36 PM
good point jonathan, i will wait till it's all working then make a new one.

Jonathan
08-01-2011, 05:10 PM
good point jonathan, i will wait till it's all working then make a new one.

Here's a couple of photos of mine, pretty self explanatory...

h4ppy-chris
08-01-2011, 05:26 PM
cheers mate that's give me some think to think about.

h4ppy-chris
09-01-2011, 11:31 AM
how do you get started! i am using autocad then lazycam.
say i have a 10x10 cm x 5mm piece of ally clamped on the mill bed, and want to put a hole in the center.
how do i set mach3 up?
.
1. load in the gcode.
thats as far as i am can you help?

blackburn mark
09-01-2011, 11:59 AM
easy way is to cut air to see where its start/reference point is
you will have stipulated this when you drew it up
it may need to be zeroed in on one of the corners of you block or it my start from the dead centre
im guessing it depends on what the default is if you didnt stipulaite this yourself in lazycam

i tend to cut air to kick of with, just run the first couple of lines to make sure youve not made any big mistakes

edit: if you have a look in the tool path window in mach that should give you a clue as to where the tool will start from in comparison to where it will make the first cut

h4ppy-chris
09-01-2011, 01:12 PM
mark the sooner you can come over to my house the better. before my head pops, did you get my text?

blackburn mark
09-01-2011, 01:15 PM
did you get my text?

no ? er hang on a mo my phone is flat:redface:

blackburn mark
09-01-2011, 01:20 PM
got it, ill give you a shout later

h4ppy-chris
09-01-2011, 01:26 PM
nice 1, i ordered my x and y motors yesterday :)

M250cnc
09-01-2011, 02:32 PM
how do you get started! i am using autocad then lazycam.
say i have a 10x10 cm x 5mm piece of ally clamped on the mill bed, and want to put a hole in the center.
how do i set mach3 up?
.
1. load in the gcode.
thats as far as i am can you help?

Maybe this will help

http://www.mycncuk.com/forums/showthread.php/3039-Edge-Finding-For-Newbies?p=19965#post19965

Phil

blackburn mark
09-01-2011, 02:45 PM
Maybe this will help


i was thinking the problem was more one of orientation between drawn part and machine bed and material... eg: sussing out the work flow from CAD to CAM to MACH to material

youll have to let us know chris

M250cnc
09-01-2011, 03:15 PM
i was thinking the problem was more one of orientation between drawn part and machine bed and material... eg: sussing out the work flow from CAD to CAM to MACH to material

youll have to let us know chris

I have updated MY post to show the part is drawn in CAD at the lower R/H portion of XY Zero

It doesn't make any difference in which position you draw it you just put it in the same position in Mach3

Phil

blackburn mark
09-01-2011, 03:33 PM
I have updated MY post to show the part is drawn in CAD at the lower R/H portion of XY Zero

It doesn't make any difference in which position you draw it you just put it in the same position in Mach3



ok
i think it might be it a little simpler to stipulate in cam that i was starting from a corner

M250cnc
09-01-2011, 03:51 PM
ok
i think it might be it a little simpler to stipulate in cam that i was starting from a corner

It doesnt matter where you draw it in CAD you just put it in the same place in Mach3

Phil

blackburn mark
09-01-2011, 04:21 PM
It doesnt matter where you draw it in CAD you just put it in the same place in Mach3



not sure if we have our wires crossed phil ?
in CAM not "CAD" you dictate atributes of the tool path, if your tool path starts in the center of a block you need to do a bit of maths phyisicaly place the tool in the center of the block to start

if your starting from a corner you only have to zero in on that corner set your hight and the gcode will jog to the centre and start cutting

h4ppy-chris
09-01-2011, 04:54 PM
cheers guys.

h4ppy-chris
12-01-2011, 07:45 PM
motor tuning is doing my headin :confused::confused::confused:
i want my motor to turn 1 rev and when it does, i want it to show 5mm in mach.
my motor is 200 steps 1/8 any help pleazzzzzzzzzzzzzzzzz

blackburn mark
12-01-2011, 08:26 PM
steps per = 320 errrrrm.... hang on, what micro step setting are you using on the board ?

its ages since i did mine, if your using 1/16 micro step and your screws are 5mm pitch then you have 1600 steps per revolution of your stepper that adds up to 5mm
devide your seps my 5mm to get your 320 steps per unit (1mm)
i think :)

Jonathan
12-01-2011, 08:57 PM
steps per mm = motor steps*microstep/screw pitch

For instance, 200 step motor, 5mm pitch screw and you say 8th stepping:
200*8/5=320 step/mm

h4ppy-chris
13-01-2011, 11:31 AM
i tryed putting in 1600 steps, put 5mm into mack and the motor span 2.5 revs ish.



when i use these settings and put 5mm in i get 1 rev this is why it's doing my headin :rofl:
what am i doing wrong.
3613

M250cnc
13-01-2011, 12:24 PM
Chris

The formula is 200 X (Micro Steps ?) = steps per rev

The amount the screw turns 1 rev (5mm i think in your case)

In my machines i use 10 microsteps so the formula is 200 x 10 = 2000 / 5 = 400 steps per rev

The velocity in the Mach setup tab is the fastest you are allowing the machine to run in your case you have set it to 600mm per minute which is on the slow side

So if you divulge you micro step setting your figures can be confirmed but 640 (Your Setting) steps per equates to 16 microsteps and the generally accepted maximum is 10

Phil

h4ppy-chris
13-01-2011, 01:26 PM
how did i set it to 16 microsteps? is that the 1/16 setting on the board, and i need to change it to 1/8?
i have set the dips to the 1/8 setting at the mo.

this is from the post on these boards
"The 1/8 step was reversed with 1/16, a fairly minor problem but still irritating as I had a scaling error on movement until I figured it out."

by the way a BIG thanks to all that have helped me so far.

M250cnc
13-01-2011, 01:46 PM
Well if you have it set to 1/8 then steps per rev = 320

Phil

Sent from my HTC Desire using Tapatalk

h4ppy-chris
13-01-2011, 05:47 PM
well it turns out it was the board!!!!! i bought a board with 4 axis 3A that turned up today, pluged it in sorted it out and all work as it shoud.
the 3 axis board the y axis just stopped working so am on with getting it replaced.

Jonathan
13-01-2011, 09:07 PM
Oops double post.

Jonathan
13-01-2011, 09:11 PM
Hmm, nobody noticed my post #86...


In my machines i use 10 microsteps so the formula is 200 x 10 = 2000 / 5 = 400 steps per rev

I think you meant steps per mm there. Little misleading - implies that 200*10 = 400 but maybe that's just me being pedantic.

What was wrong with the board? Missing lots of steps?

h4ppy-chris
13-01-2011, 11:24 PM
"What was wrong with the board? Missing lots of steps?"
dont know mate just was not playing the game, when i set 320 steps it just span like 12 revs and was set to 1/8 on the board.

h4ppy-chris
14-01-2011, 09:48 PM
well thanks to you guys i got the z axis up and running :smile::smile::smile::smile::smile::smile:

the last cut on my motor boss and a look at my workshop

http://www.youtube.com/watch?v=0VV7D8341e0

i have drilled thousands of holes, but my first cnc drilled hole was amazing.
you guys that have got it all sorted must orgasm every time you start a job :rofl:

http://www.youtube.com/watch?v=E5ykZbYe0VE

when the motor is not moving is it supposed to make a noise?
if not why is mine and how do i stop it!!

Jonathan
14-01-2011, 10:07 PM
when the motor is not moving is it supposed to make a noise?
if not why is mine and how do i stop it!!

Good to see you've got it working :) I did the same video/test as you did...

http://www.youtube.com/watch?v=Am1rMLay_Nk&feature=related

That was a long time ago now!

If I recall correctly my motors make a highish pitched noise when stationary - quiet though.

h4ppy-chris
14-01-2011, 10:25 PM
so it's normal and doing no damage ?

Jonathan
14-01-2011, 10:48 PM
so it's normal and doing no damage ?

I think it's fine but I may be wrong! Not a loud noise?

The steppers will make nice noises when they're moving.

h4ppy-chris
14-01-2011, 11:24 PM
its a high pitched sound that changes when you jog it on, at certain ponts it stops!

h4ppy-chris
16-01-2011, 02:13 PM
when i came to take the x axis of it gets this far (see pic) and stops.
is there some thing i need to remove?


3624

Jonathan
16-01-2011, 02:24 PM
when i came to take the x axis of it gets this far (see pic) and stops.
is there some thing i need to remove?


3624

That looks about as far as my milling machine will go. That's probably your maximum travel?
Unless there's something in that T slot on the front of the bed getting in the way...I had that happen.

Jonathan
16-01-2011, 02:26 PM
Oh wait. I might have misunderstood you. Are you trying to get the bed off completely? If so I'm not sure, mine just came off when I removed all the relevant bolts. I was going to scrape it...

h4ppy-chris
16-01-2011, 02:57 PM
yeh just want to take it off but can't see whats stopping it.

C_Bubba
16-01-2011, 03:31 PM
remove the gib strip so you can lift the table a bit and slide it over the X axis nut.

h4ppy-chris
17-01-2011, 04:21 PM
thanks mate :)

h4ppy-chris
18-01-2011, 09:50 PM
only got the z axis working at the min but it helps a lot

http://www.youtube.com/watch?v=jOOyh1NwK-8

and then there is this lol

http://www.youtube.com/watch?v=JYDfu457Kzo

blackburn mark
18-01-2011, 10:53 PM
YEEEEEHAAAAAWWW!!!!!!
yes it does beat holding the motor chris but you had two hands free, you could have held on to the Y stepper and had some of that 3 axis Action :)

h4ppy-chris
18-01-2011, 11:09 PM
steady cowboy 1 step at a time lol

h4ppy-chris
23-01-2011, 08:26 AM
useing Z & X to make the X axis motor mounting plate :naughty: its a fantastic buzz watching my mill slowly come to life :smile:


http://www.youtube.com/watch?v=JTXBDvV-U3c

Jonathan
23-01-2011, 02:21 PM
Nice - almost there!
Have you got a photo of the motor mount?
Did you use backlash compensation in that video?

M250cnc
23-01-2011, 04:13 PM
Nice - almost there!
Have you got a photo of the motor mount?
Did you use backlash compensation in that video?

I must have seen a different video as i couldn't really see that much detail. :confused:

This is not a criticism of Chris's video btw.

Phil

h4ppy-chris
23-01-2011, 04:30 PM
Nice - almost there!
Have you got a photo of the motor mount?
Did you use backlash compensation in that video?

i will put a photo up when it's finished mate.
yeh i used backlash compensation in that video how did you see that lol

h4ppy-chris
23-01-2011, 04:32 PM
no problem Phil vids are just using my mobile phone so not very good.

h4ppy-chris
25-01-2011, 05:45 PM
here you go jonathan X motor mounted fited and working :smile: no more G clamps :heehee:
now on to the Y axis :naughty:


3662

h4ppy-chris
28-01-2011, 10:42 PM
well am buzzing my tits off :smile::smile::smile:
got the X axis made and tuned for now :naughty:
so thought why not G clamp the Y motor down and make the Y axis motor mount plates :naughty:
thanks guys for all your input and encouragement keep it coming.


http://www.youtube.com/watch?v=f9z5oMcTq6k


http://www.youtube.com/watch?v=DY_poeUbdDA

blackburn mark
29-01-2011, 02:21 AM
chip flaps ! well posh :smile:
your almost there man

cutting circles !!! ooohhhh the power:smile::smile::smile:

M250cnc
29-01-2011, 11:43 AM
Hi Chris,

Good work on the machine, the videos are getting better also.

I hope the next thing you are gonna fit is guards for the belts especially the Y axis. You may end up having a nasty accident with your gentleman sausage. :redface::redface::redface:

Phil

routercnc
29-01-2011, 10:49 PM
Hi Chris,

Interesting stuff, keep it up. A good example of CNC bootstrapping there, using the machine to make parts for itself before it is finished.

h4ppy-chris
31-01-2011, 12:49 AM
thanks guys for your kind words, now got the Y axis fitted and working. will post pics and vids tomorrow.

h4ppy-chris
31-01-2011, 12:53 PM
here's the vids now i need to do some tidying up :whistling: happy watching :smile:


http://www.youtube.com/watch?v=WPPmTw-yb7c


http://www.youtube.com/watch?v=sKKUU1JsGRU


http://www.youtube.com/watch?v=5bczu5WqZDU


http://www.youtube.com/watch?v=1L6IqJD3eto

Jonathan
01-02-2011, 01:30 AM
Victory is mine! [4th video]

Hey that's a phrase I use!

Anyway, looking good. What's the finish like on the edges of the aluminum plate you just machined?

P.S. Strictly speaking aren't they F-clamps not G-clamps...

h4ppy-chris
02-02-2011, 12:55 AM
finish was good mate not the best but hey am just starting.
was just pleased from paper to cnc :naughty:

me thinks the lack of response to this tread its now run its course



Hey that's a phrase I use!

Anyway, looking good. What's the finish like on the edges of the aluminum plate you just machined?

P.S. Strictly speaking aren't they F-clamps not G-clamps...

M250cnc
02-02-2011, 01:04 PM
finish was good mate not the best but hey am just starting.
was just pleased from paper to cnc :naughty:

Chris did you leave material for a finish pass ?

Did you climb or conventional mill the parts ?

Phil

h4ppy-chris
04-02-2011, 12:37 PM
Chris did you leave material for a finish pass ?

Did you climb or conventional mill the parts ?

Phil

hi Phil
conventional mill, no material for a finish pass as i am still getting my head around the software.

M250cnc
04-02-2011, 01:05 PM
hi Phil
conventional mill, no material for a finish pass as i am still getting my head around the software.

Hi Chris

You could improve your finish greatly by leaving a small amount for climb milling. Cutters can wander when roughing so you need to leave enough that everything cleans up.

Trial and error plus experience, all things that take time to learn.

So it's worth spending some time to learn do that. Are you using any cad and cam software ? or mention your procedure to get your code.

Phil

h4ppy-chris
05-02-2011, 12:15 PM
Phil i use autocad/cambam/mach3, i will have to look at material for a finish pass. cheers mate


Hi Chris

You could improve your finish greatly by leaving a small amount for climb milling. Cutters can wander when roughing so you need to leave enough that everything cleans up.

Trial and error plus experience, all things that take time to learn.

So it's worth spending some time to learn do that. Are you using any cad and cam software ? or mention your procedure to get your code.

Phil