[yotawheeler]

ok so....i have been wanting and thinking of building a CNC for a fair while now but never really had the chance, however i want to start actively researching what i need to know to build one so...here is what i know i will need. maybe even buy parts piece by piece.

-computer with a CAD and or CAM program, i was thinking autoCAD and Mach3

-motors, actual size will depend on what size the table is and the weight/cutting speed i want but probably something in the 200 oz range for a table under 4x4 (i dont see reason to build it bigger unless i built it for my dad who does custom carpentry)

-motor driver, now here is where it starts getting a little bit sticky for me...i understand that i will need a driver for each motor unless i go with something like the gecko G540 -which i can plug all my motors into and its just 4 of their 250 drivers on one board but if i go with the 540 does that mean that i can safely go directly from my computer to the gecko and straight to the drive motors?

-power supply my brother in law was going to school to be a computer builder/whiz kid so...he knows a lot about them and building them, he figures that i should be able to use a computer power supply

-also is something like the MP3000 PC to machine interface by CandCNC required for everything work properly? im pretty sure it does not replace the gecko drivers so....whats it do?

also, limit and "home" switches how/where are those wired into? do they go to the driver or the interface or...?

and past that...what am i missing here guys? i have been lurking this forum off and on for probably over a year now and finally got my act together and got an account.

like i said i have been fascinated with the idea of building something where i can draw it in cad mash the go button and pull a part of the table (yes i realize there will be some messing around in between)

any help would be much appreciated thanks in advance

[JD_Mortal]

The gecko controls are the DIY base-line standard, as I see it. However, a computer power-supply might not have enough voltage to keep the driver part of the G540 happy. I believe the specs I saw, said 18-50v.

Translation: Without a load, the 12v supply will turn the motors, but will not operate safely under load.

12v, even regulated to a constant 12v, will result in about 9v at the motor with high amps, under load. Using a higher voltage, say 24v, will show as 18v at the motor, which will result an an amperage value that the controller can handle.

I hate that controllers say things like, 18v-50v, and then they say things like 1.0a-3.5a. That says nothing to anyone without a degree in electronics, and implies that we have oscilliscopes or $800.00 multi-meters on hand.

They always leave-out the wattage limitations, which is the most important, and often least mentioned specification of many devices. Instead, they give useless charts, which show specific, "perfect world values". Values that NEVER occur in production while using these devices.

Roughly... You can/will wrongly assume that the device has these values...
18v @ 3.5a = 63w (Wrong, 3.5 amps is the maximum total, at any voltage.)
50v @ 1.0a = 50w

However, it can handle 50v @ 1.0a = 50w (x2 outputs only). So this tells you that the maximum rating of the device is actually 100w. (Now why didn't they just say that!)

In any event, this driver would work, just not as expected with a 12v source. (You can modify a PSU to produce 24v, at half the amperage. Eg, a 300w PSU will produce 25.0a @ 12.0v, but it will only produce 12.5a @ 24.0v = 300w.)

The "stops", "limits", and "homes" go to the LPT/PP portion of the controller/driver combo. If you don't have a combo board, they will simply go to the controller break-out board. These are the INPUT connections to your computer. As opposed to the OUTPUT connections which go to your drivers. (You only have a limited number of inputs and outputs, so the more motors you are controlling, the less dedicated inputs you can have. Homes usually require dedicated inputs, but it is possible to use one home for all axis'. Stops usually are a last-resort, like an emergency stop, and are usually bundled as one input for all axis'. Limits, since they tell the axis motor to reverse, or pause, need separate inputs. Home usually checks one input at a time, and knows which axis it is testing. Limits are unaware which axis needs limiting, and thus, need to know which one just reached a limit. Stops don't care which axis, as they simply tell the whole machine to turn-off due to having gone out of range. Any switch out of range usually requires human intervention. Limits allow computer correction and can act as HOME switches too.)

In any event, sensors and switches are all optional. None are required for operation. However, for better, faster, safer, accurate operation, some switches and sensors are needed.

Remember, you can always add another LPT/PP port for adding more sensors. You just have to add another break-out board and set the connections to being all as inputs. Now, making the software work with two ports is another story.

[JD_Mortal]

Home, Limit, Stop switches are hooked-up to the INPUTs on the "controller" board.

Home and Stops can be all linked as one, using a normally-closed setup...

SW-x1(Hx), SW-x2, SW-y1(Hy), SW-y2, SW-z1(Hz), SW-z2 all NC switches. Connect one wire of one switch to the INPUT COMMON, and then connect the other wire from that switch, to the next switch. Until you have no more switches and one unconnected wire. The last wire goes to he INPUT SW1. Now if any of those switches are "thrown", or become OPEN, the connection breaks, and the computer can react. (6 switches in all, 2 per axis, at furthest extents.)

When used as a HOME (Hx,y,z), the computer only moves one axis at a time, towards the desired STOP. Since it knows that it is HOMING, and not MILLING, and it knows it is traveling on only one axis... It knows that any break is the STOP/HOME of that axis.

When using a LIMIT setup, each axis has two switches wired the same way, and each axis on one INPUT per axis. The computer knows that it is either RIGHT or LEFT, for instance, so breaking any connection on that axis, is the same as breaking the RIGHT if it is RIGHT, as it would not break the LEFT switch while moving RIGHT. Thus, only one per axis is needed. However, the reason you need a separate set for each axis... To correct X, it needs to know that it is at a LIMIT on X, not triggering a Y switch, since it is/may also be traveling on Y axis also. (Unlike a HOME, which travels one axis at a time. 6 switches in all, grouped in twos, each group on one axis and having separate input connections. Switches should be before the STOP or HOME switches, giving the computer time to reverse, or limit travel before hitting a STOP switch. You can also use limit switches to slow-down the cutting near an edge if you have enough inputs and switches, prior to hitting a reversing limit or stop.)

Switch Wiring...

HOME/STOP (STOP! You'll crash into the frame! ACTION: Immediate stop. Except when finding home when no limits exist.)
(INPUT COMMON) to [SW x1] to [SW x2] to... [SW z2] ... to (INPUT SW1)
Optionally, you can create a manual-stop switch too. (This is not a LEGAL "Emergency stop".)

X LIMIT (YIELD! Your close to crashing! ACTION: Slow, stop or reverse. Use as home, if you have them.)
(INPUT COMMON) to [SW xL] to [SW xR] to (INPUT SW2)
Y LIMIT
(INPUT COMMON) to [SW yL] to [SW yR] to (INPUT SW3)
Z LIMIT
(INPUT COMMON) to [SW zL] to [SW zR] to (INPUT SW4)

NOTE: A LEGAL "Emergency stop" is one which physically (directly) kills all power, without the use of an automation control IC. Eg, a physical "breaker" or other power breaking device killing any power from going to the power-supply and IC controller. (Legal safety will not allow for IC stopping, which can fail in the event of a short-circuit or due to IC errata which would stop the stop-button/function from functioning.)

[ger21]

200oz motors are too small.

As was mentioned, a PC power supply is too small.

Your best bet for a 4x4 would be a G540 package with motors and power supply.

Generally, the parallel port is connected to a breakout board. Typically, all your switches and motor drives are connected to the breakout board.
Simple ones just provide screw terminals, while more expensive ones provide additional functionality. There are many to choose from. The G540 has a breakout board built into it.

The MP3000 is made for Plasma cutters, and has additional Torch control. For a router, you'd look at their UBOB. But with a G540 you won't need one, unless you add a second parallel port for additional inputs or outputs.

[yotawheeler]

wow hey thanks guys for all the info!

JD: thanks for all the info, i have since looked around and found power supplies to be reasonably price. unfortunately im going to have to do a bit more research before i fully understand all the info you have given me on wiring, but ill get there and it will all make sense haha

ger: so what size motors should i be looking at if i were to run a table about 4x4 size? 300 oz/in or so per axis?

also what do you guys think of these packages from cncroutersource.com
CNCRouterParts
are they a good "deal"? would i be better off piecing a system together myself or maybe even looking for a similar package off of ebay? the one things i have noticed about most of the ebay packages is that lots of them dont come with the gecko drivers...s

[ger21]

Most use 381 oz with the G540, either from CNC Router Parts or Home

Most of the packages on Ebay from China are poorly matched, and typically over rated for current and voltage. A lot of people have them fail.

[hemsworthlad]

wow hey thanks guys for all the info!

JD: thanks for all the info, i have since looked around and found power supplies to be reasonably price. unfortunately im going to have to do a bit more research before i fully understand all the info you have given me on wiring, but ill get there and it will all make sense haha

Just be aware that it's not simply a case of finding a power supply that fits in between the G540's voltage range (or any other driver for that matter).
Voltage plays a big part to the speed of a stepper and needs sizing according to the motors used, yes the motor will work with lower voltage range but the speed will be slow.
For a quick guide to sizing PSU work on a max voltage of 20x the smallest motors rated voltage and a ampage of 68% the total amps of all motors used.
IE With 3 x motors speced 2.7v & 4.2A PSU needed for best performance when wired Bipolar Parallel would be 54V @ 8.5A. (Warning thats the spec of motors I use in UK there not suitable for G540's 3.5A limit)

Regards amps it's not neccesory to have the same amount as all motors connected because your never going to run all motors to the point they all pull max amps at the same time and if for some very strange reason they did then it would probably be for such short amount of time to be of no issue. 68% is the ballpark figure but allowing a bit more overhead doesn't hurt and the motor's/drivers etc will only ever pull what they need and so as long has they are not under sized more amps wont hurt, it just tends to cost more for large Amp PS so why buy bigger than needed.

like i said i have been fascinated with the idea of building something where i can draw it in cad mash the go button and pull a part of the table (yes i realize there will be some messing around in between)

CAM Software CAM not CAD is often the most difficult part for user to get to grips with and can take months or years in some case's to get confident to the point you know exactly what the machine's going to do and when, even then it catch's you out and bites you big time if not treat with respect.
Dont under estimate this portion of the build it's a conciderable learning curve even for the computer literate.

[Woodbutcher-59]

also what do you guys think of these packages from cncroutersource.com
CNCRouterParts
are they a good "deal"? would i be better off piecing a system together myself or maybe even looking for a similar package off of ebay? the one things i have noticed about most of the ebay packages is that lots of them dont come with the gecko drivers...s

Hi,

FWIW I just bought a 4 axis kit from CNCRouterparts and am very pleased so far...my new machine is not ready yet, but I have had the motors spinning !!

I gotta say the Gecko G540 is an amazing little box....4 Drives and a breakout board and all the functions you're likely to need.

With this package, the motors are closely matched to the G540 and from what I can tell, they seem way better than my previous system that was mix and match off Ebay....(chair)

The prewired connectors and cables are nice too.

Also, you mentioned in your original post about CAD and CAM...

Autocad is your CAD Program...
Mach 3 is a control program...sends Gcode to the Router....

You would still need a CAM program to generate the Gcode....

I'll throw in a plug for Vectric software....CAD & CAM together....check out Vectric.com -- All Vectric programs and Mach3 have trial versions you can work with right away...

Hope this helps and have fun...

Jeff

[JD_Mortal]

The only reason I suggested that computer power supplies would be acceptable, was due to the availability and cheapness of them. They can be wired for 24v, which is potentially dangerous, but possible, for 1/10th the cost of an equal power supply.

Technically, you could use a 60oz/in motor, and have enough power. Though you might not like the speed at which it needs to be geared-down, to operate with enough force. (A 10 turn/inch screw turns a 60oz/in into a 600oz/in motor at 1/10th the speed.)

Though the standard, for DIY, seems to be Gecko G540 or china-boards... It is not the "best" option. When it comes down to the brass-taxes, you will want to look into "Raw power", in exchange for "Novelty luxuries". When you get deep into cutting, and know what you are doing, you will end-up using a hand-built or industrial driver and power-supply. (Not a good choice for a starter. It will over-burden you, and make you quit, as so many others have done. That is why there is an abundance of half-finished toys on ebay.)

Get-er-done, and learn as you go. You can break your first $500-$800 table, and be better off than the guy who built a $5000-$8000 table, and can't afford to make repairs to keep it going.

Just shy away from the $200-$400 packages/promises. The individual components add-up quickly. Even the cheapest ones that have functionality greater than 100 hours.

In the end... keep these things in mind...

Power-supplies need to provide more than 150% of your total consumption demands. Controllers and drivers only convert about 40% to 80% of consumed power into actual work. The rest of the consumed power is turned into "waste-heat". (This is why most power-supplies are so excessively large.)

What is your consumption... Drawing and foam-cutting will be about 2x the motors rated specs. Soft-stuff will be about 4x your motors rated specs. Hard stuff will be about 8x your rated specs. (Running at 8x your rated specs will also require additional cooling. Due to the excessive wasted-heat that will build in the motors.)

When you don't have the desired power-ratings, you simply have to go slower and stop more frequently, and home more often. Speed will be the sacrifice to gain your lost power.

If you have 600oz/in motors that operate at 12v @ 3a (36w), times three motors = 108w, plus 50% in losses = 162w total. That is the 1:1 or foam-cutting requirements. 324w would be for milling soft things. While 648w would be for milling medium things. (That does not include the spindle power consumption, just the consumption of the three steppers.)

While you would need 648w for medium things, you may still be limited to something like 3-6a per motor/phase. That comes to about 9-18a for peak-use. Using the 18a value, divide your 648w by that, and you get 36v. You will need to push the motors with 36v avg, which can be 72v at 1/2 steps and 1/2 amps... Into that 12v motor which has a limit of 3a.

Confused yet?

Short version, example...
3x (12v @ 3a = 36w) = (12v @ 9a = 108w nominal for three)
108w x 1.5 {losses + consumption} = 162w
162w x 2 {soft stuff} = 324w PS needed [12-24v]
162w x 4 {med stuff} = 648w PS needed [24-48v]
162w x 8 {hard stuff} = 1296w (1.3Kw) PS needed [48-56v]

You can go less, more is just wasted power regulation. You don't want to run 1.3Kw all day long. That is like running your dryer all day.

Why use higher voltages? Higher volts, at the same wattage, uses less amps in the wires. Amps are what kills wires. The higher the voltage, the more the heat is pushed out to the ends, the motors or back to the limiting controllers. Higher voltages also translates into faster speeds, or it helps you regain lost speed from high-torque gearing setups.

Why use higher amps? Higher amps, at the same wattage, delivers more magnetic torque/power to the coils. You loose speed, gain torque, and reduce efficiency at that cost. (The higher the heat, the more resistance, the more amperage created, the more heat created... endless cycle. Manageable only with additional cooling.)

Like the difference between an ignition coil and an electromagnet... The higher voltage will quickly shoot across the wires, generating almost no heat from an ignition coil running at 60,000vac and 0.01a (600w). However, it wouldn't have enough power to attract a 1-lb metal bearing. On the other hand, an electromagnet with 6v and 100a (600w), will lift over 100-lbs of bearings. The ignition would push a 0.1g magnet to sonic speeds, but the electromagnet would barely make that same magnet flip-over.

Yea, I over-explained again... sorry...

Just cheat like everyone-else does... find a setup that works, and copy it. (There are many great video's of running machines and some parts listed for you to make decent judgement.)

[hemsworthlad]

JD While I mean no disrespect to you and to some your explinations may mean something. . . . BUT . .The majority of folks on here are for looking help in choosing Drive,motors etc for hobby use not industrial.

Post's like this only serve to confuse not help. . . . please be mind full to who you post because you could be putting people off building.

It's not rocket science building power supplies and control box's to do the work we need them to do and Statements like Gecko's being "Novelty luxuries" is ridiculous and i'm sure mariss fremaniss would love to tie you up in knots as to why not.
The fact is 1000's are using them (me inc) for hobby use as well as industrial and they work perfectly well and are in no way under performing. Your words make it appear they are inadequate for the job and again statements like. . . . "When you get deep into cutting, and know what you are doing, you will end-up using a hand-built or industrial driver and power-supply" . . . will be very off putting to folks just looking to get into HOBBY CNC plus your wrong.! The percentage that have done what you state will much less than 1% and I've yet to speak or read of anyone abandoning drives like Gecko's in favor of building there own drive.! . . . FACT is more do it the other way round and try building there own only to fail ending up buying gecko's after blowing loads of time and money.

Folks reading this forum need guidance and support that is preferably put in layman terms not unhelpfull mind blowing TOSH.!

[jlnading]

Try these two sites, I was very satisfied. http://www.candcnc.com/ CNC Parts Kit have a good one, Jeff.

[JD_Mortal]

Sorry if my post was found misleading or discouraging...

The "novelties", were not directed towards gecko only. You made that implication, not me. The term novelties is commonly used to describe "things you don't need, but they are included without choice. Eg, you paid for something you don't need, but you had no option to NOT buy it. Not all controllers/drivers have novelties. When/if you need novelty-free raw power or movement or control, there are cheaper options. (Don't imply, again, that the above statements are for "Gecko". If Gecko has novelties, and you purchased them, perhaps your implication was justified and logical, don't get defensive about it. Novelties are not bad and it was not used in a derogatory statement.)

I was implying that Gecko drives were more towards the industrial side of things. (Though they are not found in "the industry". Large corporations, being "the industry", use Honda, Mitsubishi, Toyo, etc... Gecko is a DIY and small-business platform. They are at the upper-end of the "hobby use", and the lower end of the "industrial use".)

I was not suggesting that anyone try to build a power-supply and drivers by hand. I explicitly stated that "hand-built was the best solution for raw power", built by anyone not specifically yourself, when you know what you want, as opposed to, "off the shelf, automated-built, pre-fab, do-all parts", which just have added expenses for things that you don't need.

Poor guidance and understanding leads to failure, not building itself. If they are not aware of the involvement, it is better that they get discouraged before spending/wasting hundreds of dollars in something they will never complete. Are you saying that we, as a social forum, should hide information so they fall in debit buying "all the wrong things", and then later get discouraged when they realize they never had the ability or finances to complete something close to their expectations?

Being a "hobby" does not say anything about desires...

If my "hobby" is milling steel (hard metals), cheap china-boards and computer power-supplies will just waste my time. (As I stated.)

If my "hobby" is cutting Styrofoam or drawing or cutting balsa-wood (soft things), then industrial grade drivers and power-supplies with 30a+ ability are overkill. (Also as I stated.)

I simply put up a rough guide, with considerations that NEED to be taken into account, when building a CNC for "Your hobby", whatever that requires. For a "first time builder".

Ok, defensive mode off...

We can throw thousands of, "things to buy" at him... However, without telling him why he might need it, or what to look for... we are just injuring him with everything that bounces off his head, which we threw at him. Personally, I like Gecko's. However, I also like china-products and industrial products found in actual production plants that have more than 40 employee's and have millions of dollars in hardware invested in production.

[ger21]

Gecko is a DIY and small-business platform. They are at the upper-end of the "hobby use", and the lower end of the "industrial use".

Only 10% of Gecko's business is to the DIY and hobbiest market. 90% of their drives are used in commercial applications. Not necessarily CNC, though.

Short version, example...
3x (12v @ 3a = 36w) = (12v @ 9a = 108w nominal for three)
108w x 1.5 {losses + consumption} = 162w
162w x 2 {soft stuff} = 324w PS needed [12-24v]
162w x 4 {med stuff} = 648w PS needed [24-48v]
162w x 8 {hard stuff} = 1296w (1.3Kw) PS needed [48-56v]

Raising the voltage give you more torque at higher speeds. At low speeds, torque is the same regardless of voltage. Typically, softer materials require higher speeds, which is the opposite of what you're saying.
I don't think choosing power supply voltage should be dictated be the hardness of the material you're cutting.

I think a much better way to choose your components is to decide what kind of performance you want, and work backwards from there. Decide how to drive it, and how much torque you need and at what rpm. Then choose a motor that can give you the performance you need. Once you have a motor, and know what it needs to do, it's easier to pick a drive and the appropriate power supply you need.
That's how the commercial motor choosing software works. Tell it how much weight your moving, how fast you want it to go, and how fast you need to accelerate it. Then just buy what will do that for you.

[Jerry3672]

Great thread Guys.

I'm building a router myself and you have helped me with some basic information. Keep it coming.

[yotawheeler]

ok so my main goal in building a router is mostly hobby use and most probably to machine aluminum, wood, plastics ect. one project that i have my sights on is a CNC plasma cutter, i have the plasma but want to build a table, i thought that i could make a much better/professional machine if i had a small CNC router to do some of my parts with. i will probably use the gecko driver as that is what me eng instructor advised i posted this thread mostly to make sure that i hadnt overlooked any components that i would need and i think that i have a fairly good idea of what ill need. while i dont have a very in depth knowledge of what i need...i think i know enough to get myself into trouble and that i can learn fast enough to get myself out with a reasonably usable machine

i think that if/when i get around to building a little router this kit will do fairly nicely:

CNCRouterParts

my other reason for wanting to build a router first is that most cnc plasma builds i see tend to cost in the $5-10k range...a router would probably cost me 1k or less as most of the materials for the table and gantry i can scrounge from my fathers carpentry shop. also i could use the same mach3 software to power my plasma table when its completed

I appreciate everybodys opinion that has taken the time to post in this thread i also know though that what people on the net say is not gospel and i will look into things more before i spend any of my hard earned cash so...a little less (flame2) and ya

thanks guys!

[JD_Mortal]

Raising the voltage give you more torque at higher speeds. At low speeds, torque is the same regardless of voltage. Typically, softer materials require higher speeds, which is the opposite of what you're saying.

I said nothing about speeds, related to the material. I only mentioned torque. Torque is achieved by reduction of speed through gears or motors. Motors with higher torque require more voltage to obtain the same speed.

The "example" was simply to show the comparison of power demands which will ultimately be required for "equal" operation. As per every spec-sheet and taking into consideration the exponential losses of consumed power. Heavy things require more power to move them around, heavier structure to hold them and the milling tools, and more powerful and wasteful motors/gearing.

Thus... cutting balsa-wood, fast, requires only 12-24v of power to move 24in/min. While cutting steel with a blade, slow, requires a motor with 48-56v of power to move 6in/min. (Due to the fact that the gearing/drive would most-likely be 20:1 for steel, while the balsa-cutter might be closer to 2:1)

In any event, it will be unrealistic to expect to efficiently, in a reasonable timeline, cut steel with a blade, using 12-24v, in the 324w range, which is 27.0-13.5a. (Those amps at 12v will NOT be safe while milling steel. You will be near MAX at all times, due to the low volts which results in higher amps.)

While it would be realistic, in that same scenario, with a heavy-rig, to cut steel using 48-56v, in the 1296w range, which is 27.0-13.5a. (Those amps at 48v will be safe while milling steel. Due to the fact that the amps will be nearly half that, in operation, since the voltage is nearly 4x more resulting in less losses as heat, cooler operation, and thus less amps needed.)

I don't think choosing power supply voltage should be dictated be the hardness of the material you're cutting.

I agree... However, since that is the first element encountered by the entire setup... It will ultimately dictate what you are able to cut, what you are able to attach for a driver, and what speed you can ultimately obtain. I don't know how you say that your, "Power source" has nothing to do with "Power you will need". You don't buy a car-frame, then the computer parts, then the gas-tank, then the wheels, and then decide... Hey, looks like I need to cram a V-12 into this jetta to make it run.

Once you have your structure setup, you go to your power, which will determine what drivers, and motors, and screws you will need for operation. No sense buying a driver which handles 60v and 5a per phase, if you can't afford, or find, a matching power-supply. If the best you can afford is only a 30v @ 18a (540w) power-supply, it makes finding drivers easier, and picking screws and motors that will yield the output you need. Though, building the structure is not advisable without knowing what you can afford to drive it...

I think a much better way to choose your components is to decide what kind of performance you want, and work backwards from there. Decide how to drive it, and how much torque you need and at what rpm. Then choose a motor that can give you the performance you need. Once you have a motor, and know what it needs to do, it's easier to pick a drive and the appropriate power supply you need.
That's how the commercial motor choosing software works. Tell it how much weight your moving, how fast you want it to go, and how fast you need to accelerate it. Then just buy what will do that for you.

A motor does nothing without power and a driver that can handle power. Software does not determine what potential any of those components has, it simply works within the limits of the available potential. Software can't make the ultimate decision of what motor/driver/power that is needed for the setup. Starting with the power-supply, the heart of the cnc. At the most, it can tell you what wattage you need, which can be any voltage/amp combo, and yield the same result... watts is watts, raw power available to you. The motor-specs is ultimately useless, as motors are driven at fractions of values, and pushed over-voltage/amps, and those specs are not available. Nor is this a commercial-budgetless build.

I agree that everything must be taken into consideration before purchase, which is what he is doing.

I just don't like having to re-design and re-calculate everything, when starting with drivers/motors, then finding out the power I need is beyond my budget, unavailable, or will ultimately destroy my rig. (This is my first CNC rig, but not my first machine built. This works for cars, gocarts, electric scooters, computers, grow-houses, etc... It helps to know everything all at once, but budget and availability always reduces the "other components", after the power-supply, because the power-supply seems to be one of the biggest hurdles. With all the posts about things melting, blowing-up, being under-powered, and "Will this work with this"... Well, it is all a hurdle at some point.

LOL, lets just agree to disagree...

What else was needed? Sensors? Switches? Bits? Spindle?

[yotawheeler]

i think to start im going to hold off on the sensors and misc switches...tooling will probably consist of mostly of 2 flute end mills so i can plunge and it will clear out properly. spindle likely a woodworking router with adjustable speed.

once i get something functioning then ill look into limit switches ect...i know that this is NOT the best way to design something but if i find that my gecko driver is not going to handle the extra sensors/switches...then i will learn to work within the limits of my machine

[hemsworthlad]

JD: Like I said respectfully I just believe your complex post's are just too complicated and deep to someone new to DIY CNC and they are much better adviced if put in layman terms.
By all means carry on giving complex advice and i'm sure the techie's will be very interested in the NOVELTY FREE RAW POWER DRIVE that your building for your own build..!!
We will have to agree to disagree . . . enough said.!


YOTA: Gecko's or the drive doesn't have anything to do with the amount of INPUTS(switch's) it's the BOB(breakout board) that handles this side of things and this limited to how many I/O(input/outputs) are available by the PP(parallel port) often you'll be left about 5 or so spare Inputs and 1 or 2 outputs for sensing and controling switch's etc. (The G540 has in built BOB)
Essentially a basic BOB is just a disribution board that makes connecting things easier and neater, the majority provide other usefull feature like optoisolation and charge pump which to SOME could be concidered noveltys.? To me they are must have features.

Limit switch's can be done very cheaply using simple micro switch's so really no need not too use them and you will have the I/O's already because their simply there by the fact the PP provides them, the BOB just makes connecting easier.
That said I dont use limits on my large machine only home switch's, I never get any where near the ends of my machine and it's never left unattended so the soft limit's feature in mach works just fine for me. Basicly it's just something i never got round to doing before finishing build and ounce I started using the machine it's become one of them job's " I'll do it later" but never gets done so be warned finish every thing before using or chances are it wont get done.!

[hemsworthlad]

Once you have your structure setup, you go to your power, which will determine what drivers, and motors, and screws you will need for operation. No sense buying a driver which handles 60v and 5a per phase, if you can't afford, or find, a matching power-supply. If the best you can afford is only a 30v @ 18a (540w) power-supply, it makes finding drivers easier, and picking screws and motors that will yield the output you need. Though, building the structure is not advisable without knowing what you can afford to drive it...

JD: Sorry just add to come back on this but your WRONG.? The desired performance and work load dictate components needed to perform and the power supply is not the first place to start. The PS just allows the motors/drives to acieve this performance, yes it's an important component but ABSOLUTLY NOT the first palce to start.
IMO Gerry's way is the right way and proven with 1000's of successful DIY builds and I think you'll find the one's that fail or end up with an under performing machine have done it some other way. . . probably yours.?

One thing I believe is important and many people get caught up in and IMO end up wasting money on is chasing rapid speeds.
To me no point in building a machine that can do 1000ipm but to only spend 95% of it's life cutting at 300ipm due to cutter/material or machine structual strength restrictions.
Better to design a machine to perform it's best while doing the main intended purpose, in our case cutting, in a machine doing lots of positional moves like a pick n place macine or machine drilling hundreds of holes then yes rapids are very important and thus should be designed for.

End of rant: Sorry Yota I wont high jack your thread anymore just my OCD got the better of me.(chair). . .Lol

[jlnading]

Just to say one thing about Gecko Drives, I know, for a fact that Continental Corp, a huge world wide company, a company who not to long ago bought out manufacturing facilities from Motorola Corp, use Gecko Drives in allot of equipment or machinery they use to manufacture electronic boards for the automotive industry. So, Gecko Drives are used not just in hobby but also in big business to, I use them to, they are great drives. Have a good one, Jeff.:cheers: