[vakeiros]

hi guys,

i recently bought a TS3040C-H80 chinese CNC mill and I like a lot but i'm thinking about making some upgrade on it.

I itend to machine Aluminium and Acrylic, for acrylic i think what i have it's enought but for Alu i think i need stronger XY motors and i think a better spindle.

i'm completely new about this, i have a few ideas but not sure if they are good, bad or non sence XD

Anyway, the motors i have are:

3x Vexta DC 2.4A 103H7124-1142 (don't know the Oz's of them) for the X, Y, A axis
1x Vexta 1.55amp C8513-9012K for the Z

the spindle it's a "200W" "0-20000" rpm (i seriously doubt about these specs XD) and it's not aplied directly on Z axis, it has a steel wire from the motor to a chuck on the Z axis. anyway i don't think this is good.

so i'm thinking about upgrade the steppers to this kit (first i have to check the dimensions to grant they're the same as the ones i have):
- 3-Axis Monster Stepper Motor Driver Kit - 3-Axis Monster Stepper Motor Driver Kit
these are 400OZ motors, don't know if the drivers/controllers are anything good but i think this it's a much better kit that the ones i have now.
i'm thinking upgrading my XYA axis with the motors and put one of the old Vexta DC 2.4A 103H7124-1142 on the Z or leave like it is i have to think about it...

the spindle i'm thinking something of this type:
CNC 400W Spindle Motor ER11 Power Supply Speed Controller Mount Bracket | eBay

well this is what i'm thinking about but i'm completely open to sugestions!

regards

[aarggh]

The steppers you currently have are rated at 140oz/in best I can tell. So they will be under-powered for heavier machining. But the new ones your looking at are way overkill, you'll get no benefit from going to such a high torque stepper with these machines. Around the 230-280oz/in is definitely more than enough grunt to do whatever you need with the machine. My large 6090 weighing in at 300kgs uses 380oz/in steppers, and these are more than adequate for frequent and heavy machining!

Ideally, as low an inductance as possible is preferable, the formula to work out the required power supply is the square root of the inductance, x 32, to give the DCV required. The steppers you linked to are 3.8mH in unipolar mode, so the standard 24v supply with that kit I wouldn't consider good enough. A good 48VDC power supply, with a G540, and some 2.3mH steppers would be a perfect combination.

The new spindle you linked to I have also not heard good things about, most of the comments on that model seem to indicate a lack of power and torque, with frequent failure rates, especially as it's a brushed motor. A proper spindle and VFD would be preferable, but you may be stuck with one of the brushed motors instead as you've linked to due to the size of the machine.

cheers, Ian

[vakeiros]

hi,

first of all thanks for the information.

the steppers i linked were my first option but they have "another" problem for me, they are from the other side of the attlantic so shipping and customs costs are a big issue, so i went for ebay and found these from Germany:
3 axis 425Oz kit | eBay

but from the 2 things you said:
- less inductance is better
- 425Oz it's overkill

from what i've seen these are 9mH so they are worse than bad lol, about the overkill i didn't care much about but ok i think the 9mH kill them.

so what about this:
3 axis 270Oz | eBay

these have 1.6mH so they are better (i think), sqrroot 1.6*32 ~ 40V so i think the 36V PSU it's not too bad and they are twice as powerfull than the ones i actually have (i must agree with you this must be more than enough) and better than all the kit it's a bit cheaper :P

EDIT: on ebay they say it's 1.6mH but on the brand specs they are 3.5mH so the 36v it's a bit low isn't it? i'll check about a 48V PSU...

about the G540 driver, well this is a bit out of budget (at least for now) but in the future i'll think about it... if i could get only the 2 steppers i need and buy the g540 apart... even so it's an 300€ only the driver... for me it's not afordable on the time being...

the spindle... well that is bad new for me i'll not do heavy machining, i'll work aluminium but not heavy stuff... on this one i think i'll take the risk... t's for small parts only and honestly i think anything it's better than the one i own right now... well do you have any sugestion on a spindle good for my machine?

PS. are you sure this motor it's brushed? i thought it wasn't :S

thank you very much for your time and info!

[aarggh]

425oz/in really is overkill, that inductance is just too high, and just wouldn't be worth it for that type of machine, but that second link to the kit is exactly what you want! The 542's are really great drivers, I have them myself in my 6090 and they are a proven, rock solid driver and performer. The G540 is better as a package, but these will do you for a long time, and as they work quite well, it's very likely you may never end up changing them. The steppers are a little high in the inductance, but with a 36v PSU it brings you close enough you won't see any detrimental effect.

For the price, I'd consider that a very good value kit. I'd be plonking down my cash pronto on that set!

At a cursory glance the spindle looks identical to the standard motor that came with a lot of these smaller machines, and the bulk of them were brushed, low power motors that gave no end of trouble. But looking at that spindle again, it looks like it may be a brushless DC motor, which if it is, should probably be not bad at all.

cheers, Ian

[vakeiros]

well Ian,

thanks again... i'll trust you on this since you look a guy who understands about this stuff :P

i guess this will be my upgrade then! soon i'll let you know how it went (should buy this stuff on the next week). i guess i'll have major revolution on my "box" driver, lucky i am good with electronics LOL.

regards

[aarggh]

One thing I'd recommend, is if you can, crimp all the wiring to ensure a good and tight compression fit on all connections. That way you can avoid intermittent issues down the track arising from things moving or working loose due to the large amount of vibration from the machine running. $20-$30 on a crimping set is well worth the little extra cost. Also makes it much easier to trouble shoot when you need to disconnect/reconnect multiple wires/sockets.

cheers, Ian

[vakeiros]

good advices are always welcome! yes i had "bad" experiences with bad connections before, result: i learn with them :P

but thanks for the heads up :P

BTW, maybe you can help me with an actual problem i'm having, i had my CNC up and runing with no problems (actual problems, nothing about the weak motors), now i've changed my computer (i had an old AND SLOW p4 1.6GHZ and upgraded to an P4 3.2GHZ with HT and so), i changed the mainboard and processor and now i'm having troubles on my X and A axis, Y and Z work flawless but the other two move very badly and shaky. i've an PCI card with a parallel port that i've installed and with this the X and A don't move at all (don't ask me about the chip of the card lol only today i've been reading and saw that not all the chips were good, i thought anyhting with an parallel port would do the job so obviously i bought the cheaper i found lol). I'm quite certain its a problem with my "new" mainboard because the problem started EXACTLY when i changed the computer... i hadn't had the time for downgrade the PC again to be sure about the problem but as we are here maybe you can help me on this... first i thought that was about lack of current on the mainboard port (i had this experience before programing PICs, newer mainboards wouldn't do the jod well because of low current on the COM port) but the Breakout board shouldn't handle with such currents right? it should be only about signal interpretation right? don't really know what's happening... o you have any knowledge on this?

thanks again my friend

[handlewanker]

Hi, when you said the spindle was driven by a wire thingy, I immediately realised it's the off machine drive set-up with a motor on a length of cable.

In my opinion this is a crap way to drive a spindle, but for that size of machine and the economy factor of it's cost you get what you pay for....amen.

Apart from being a weird way of having a drive, what are the problems with this set-up....I'm just curious......I would have redesigned the set-up to have the motor sitting directly above the spindle with a bracket etc and coupled to it.

My main curiosity stems from a garden project I just had to do........not CNC gardening....LOL.

I recently bought on EBAY one of those long pole chain saw, brush cutter, hedge trimmer outfits driven by a Honda C25 4 stroke engine, and as it is driven by a long springy wire type drive shaft, in three sections, going to 5 metres long to get to the top of trees etc, the comparison to the spindle drive with the cable motor etc, made me think of how much torque can be transmitted by a springy wire drive shaft.

The guy who sold it said it would be good for trimming max 25mm thick branches......well the tree top I had to bring down (it was dead and rotten) was 200mm diam, and by cutting from both sides the dead wood, a Cootamundra Wattle with wood a s hard as a whhore's heart, succumbed to the saw without too much bother.

I have to wonder how long that wire springy drive shaft on the router spindle will last when it's doing 20,000 rpm.....and if it's doing less rev's with a cutter in aluminium, how much torque can it deliver without shredding itself.

If that is the case, it would almost seem that all that is needed is to get a water cooled spindle, good for 24,000 rpm, and connect it with the springy drive shaft to the spindle via a small adaptor in the chuck of the water cooled spindle.

I don't think the 3040 can support the extra weight of a water cooled spindle attached to the X axis carriage without distorting it, as the X axis carriage is only riding on two unsupported round bars of steel.
Ian.

[vakeiros]

Hi, when you said the spindle was driven by a wire thingy, I immediately realised it's the off machine drive set-up with a motor on a length of cable.

In my opinion this is a crap way to drive a spindle, but for that size of machine and the economy factor of it's cost you get what you pay for....amen.

Apart from being a weird way of having a drive, what are the problems with this set-up....I'm just curious......I would have redesigned the set-up to have the motor sitting directly above the spindle with a bracket etc and coupled to it.

My main curiosity stems from a garden project I just had to do........not CNC gardening....LOL.

I recently bought on EBAY one of those long pole chain saw, brush cutter, hedge trimmer outfits driven by a Honda C25 4 stroke engine, and as it is driven by a long springy wire type drive shaft, in three sections, going to 5 metres long to get to the top of trees etc, the comparison to the spindle drive with the cable motor etc, made me think of how much torque can be transmitted by a springy wire drive shaft.

The guy who sold it said it would be good for trimming max 25mm thick branches......well the tree top I had to bring down (it was dead and rotten) was 200mm diam, and by cutting from both sides the dead wood, a Cootamundra Wattle with wood a s hard as a whhore's heart, succumbed to the saw without too much bother.

I have to wonder how long that wire springy drive shaft on the router spindle will last when it's doing 20,000 rpm.....and if it's doing less rev's with a cutter in aluminium, how much torque can it deliver without shredding itself.

If that is the case, it would almost seem that all that is needed is to get a water cooled spindle, good for 24,000 rpm, and connect it with the springy drive shaft to the spindle via a small adaptor in the chuck of the water cooled spindle.

I don't think the 3040 can support the extra weight of a water cooled spindle attached to the X axis carriage without distorting it, as the X axis carriage is only riding on two unsupported round bars of steel.
Ian.

Hi,

the problem with this set up it's exactly that, even at high RPM soon has the mill toched the Alu the RPM drop ALOT it can maintain te rpm if i move VERY slow let's say 100mm feedrate and max stepdown of 0.3mm, this takes like forever to do a part, and on my actual set up with this parameters sometimes i'd missed steps after 3mm depth (usualy i have to do parts with 6mm depth).

on my manual testes to achieve the right RPM and FR do a given mill on ALU i've easily twitched the thing.... ok i'm new at this, i'd never had programmed CNC before, hell i'd never seen a CNC live before i bought mine :P but i really like it and i think it's a good machine for me just need a few tweaks :P

regards

[aarggh]

good advices are always welcome! yes i had "bad" experiences with bad connections before, result: i learn with them :P

but thanks for the heads up :P

BTW, maybe you can help me with an actual problem i'm having, i had my CNC up and runing with no problems (actual problems, nothing about the weak motors), now i've changed my computer (i had an old AND SLOW p4 1.6GHZ and upgraded to an P4 3.2GHZ with HT and so), i changed the mainboard and processor and now i'm having troubles on my X and A axis, Y and Z work flawless but the other two move very badly and shaky. i've an PCI card with a parallel port that i've installed and with this the X and A don't move at all (don't ask me about the chip of the card lol only today i've been reading and saw that not all the chips were good, i thought anyhting with an parallel port would do the job so obviously i bought the cheaper i found lol). I'm quite certain its a problem with my "new" mainboard because the problem started EXACTLY when i changed the computer... i hadn't had the time for downgrade the PC again to be sure about the problem but as we are here maybe you can help me on this... first i thought that was about lack of current on the mainboard port (i had this experience before programing PICs, newer mainboards wouldn't do the jod well because of low current on the COM port) but the Breakout board shouldn't handle with such currents right? it should be only about signal interpretation right? don't really know what's happening... o you have any knowledge on this?

thanks again my friend

The problems you may be having could be due to BIOS settings for the port, or even the logic level being output. Laptops for example are notorious for problems with BOB's because of the voltage level they output for the parallel port. Current drain shouldn't be a consideration as the way logic design is done for IC families, their is a set fan in/out that means almost any logic family can drive TTL/CMOS without problem. I wouldn't be worrying about this. What is more likely is your port may be putting out logic levels that may need to level shifted by an interface board.

If you can, try the old computer to quickly verify it's the new pc, if it looks that way, check your BIOS settings, and if you have access to test gear, check what voltage levels your ports putting out.

cheers, Ian

[vakeiros]

yes i've forgot to say that, i've messes with the bios values and the behavior changed with some settings the motors wouldn't move at all and with others it moves something... i'm an electronics tecnician so test devices aren't a problem... i'll check the values with a multimeter and get back to you. i'll check the values of the ones moving right and compare with the others

[aarggh]

yes i've forgot to say that, i've messes with the bios values and the behavior changed with some settings the motors wouldn't move at all and with others it moves something... i'm an electronics tecnician so test devices aren't a problem... i'll check the values with a multimeter and get back to you. i'll check the values of the ones moving right and compare with the others

Ideally you want a CRO or a logic analyser, so you can also see the pulse duration, and verify the integrity of the signal. A multimeter may just show the peak value which may not give a true picture.

cheers, Ian

[vakeiros]

i already intended to take a look with the osciloscope. now that you speak on the logic analyzer i don't own one... yet but i have itentions of buying one for a while now... it might be a good oportunity to buy one lol

i'll check it with the scope then.

[handlewanker]

Whewwww, this is deep water.....a CRO and logic analiserr.........anything beyond a multimeter and I'm off..........LOL.

I've actually got a 'scope, bought it at an auction for $40.....and it works, well it turns on and you get a blip on the screen that with a bit of twiddling of the various knobs becomes a straight horizontal line.......so I bought a set of probes on EBAY, the usual things with plug in bits etc.

I can get a sine wave to materialise when I "probed" the output from a small 6 volt transformer, but what it actually signifies is beyond my ken......there are no scales apart from a slip in plastic screen on the front that is calibrated in decibels, so that sounds like it was used previously by someone with audio affinities, perhaps.

I usually leave it on the bench when my friend comes visiting and it looks very impressive just to see it there.....I was hoping he'd know what it was for.

There must be a way of calibrating it so you can interpret the read out for whatever you're testing.....all very mysterious......I can't see how this is better than a multimeter.

One thing it did tell me and that is my lab power supply has some ripples on the output when the 'scope is turned up to the max, whatever value that may be, but as to how much AC this signifies on an otherwise "pure" DC output is not apparent to this monkey.

I had some fun testing a capacitor and watching the test wave form decay as the voltage on the capacitor died.....very cool.

Those big ones seem to hold a lot of voltage for a long time I'm told.
Ian.

[aarggh]

What model is your CRO Ian? Or maybe put up a pic so I can see what the controls are?

A cheap, good old analog CRO is just an invaluable tool.

cheers, Ian

[handlewanker]

Hi......A photo, a photo, my kingdom for a photo....LOL......I've got to go out to the garage and take another photo as all my previous ones are on the hard drive of my old computer that crashed in the most peculiar way......long story........I managed to resurrect the old hard drive by installing it as a slave to get at the files on there.......most of the files I managed to back up to disc before the crash.

A bit later in the day......the previous photos turned to be of a scrap 'scope that I got for $1 at the auction.

New ones just taken.....ink still wet....LOL.
Ian.

[aarggh]

Wow that's old Ian! If you hang onto it for another 30-50 years it might be worth as much as $5 mate! ;-)

It's a 10MHz CRO, here's a link to download a manual for it, but I think it's of very limited usefulness:

LEADER LBO-52B 50MV 10MHZ TUBE OSCILOSCOPE SCH Service Manual free download, schematics, eeprom, repair info for electronics

If your fancying doing any serious playing around with a CRO, I'd be inclined to get rid of (or store away) the Leader, as there's heaps of used HP and Tektronix 100MHz 2-4 channel ones out there ridiculously cheap. I bought a military grade Tektronix 2 CH 100MHz (465M) many years back, and it's now worth barely a fraction of what I paid, but I'll never sell it. As I mentioned, an old analog CRO is just too useful. And more often than not, handier than a digital osc.

cheers, Ian

[handlewanker]

LOL......I'd better get it insured then......thanks for the info.

Some years ago a 10 Mhz was a dream machine, back in the 60's I think when I took up hobby electronics for the first time.

I'll have to think what I'm going to do with it.....hmmm 10 MHz, could probably make a spindle speed read out......10 million rpm....wow........or divide by 100.......100k spindle speed max.

It looks impressive on the bench.
Ian.

[vakeiros]

i still haven't had a chance to make the readouts...

one thing it's bugging me...

aarggh, what's the benefficts of having a higher voltage PSU, i mean you said the perfect VDC for a given motor it's given by the formula sqrroot Z * 32 but what's the consequences of a lower voltage? in my case i bought that 270 steppers with 3.6mH so "the perfect VDC" is 60v and the PSU it's 36V what will i notice?

thanks for everything

[aarggh]

i still haven't had a chance to make the readouts...

one thing it's bugging me...

aarggh, what's the benefficts of having a higher voltage PSU, i mean you said the perfect VDC for a given motor it's given by the formula sqrroot Z * 32 but what's the consequences of a lower voltage? in my case i bought that 270 steppers with 3.6mH so "the perfect VDC" is 60v and the PSU it's 36V what will i notice?

thanks for everything

It's the difference between max torque and speed. A lower PSU value will result in reduced torque and speed. A 36VDC PSU or thereabouts will generally be fine as it's not too far off 60VDC, it simply means you won't rapid quite as fast, or take quite as aggressive cuts than if you had a higher output PSU. On the other hand, if you used the standard one supplied with most of the Chinese machines, which is 24VDC, that becomes quite a large difference to the ideal of 60VDC, and you will notice the lack of torque and speed much more.

It's not a hard and fast rule you must strictly follow as there are many other factors involved, it's more of an theoretically ideal configuration, that you need to derate appropriately if altering the parameters.

cheers, Ian