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View Full Version : NEW MEMBER: Hey guys new member. advice needed



tankproof2
19-11-2020, 11:56 PM
Hi guys, i am looking into building my first cnc based around a workbee

i dont know if this is the right place to ask this but could i have some advice on my build.

i am planning to buy a 750x1000mm mechanical kit off of ali express (https://www.aliexpress.com/item/32910691183.html?spm=a2g0o.cart.0.0.3f5b3c00pATS93&mp=1) only because i think its the cheapest way to get a reasonable frame but maybe im wrong?

i then plan to swap out the x and z axis to linear rail (off ali) for around 150£

as far as motors go i am thinking 60BYGH401-03 because they are cheap and seem to have reasonably low inductance along with this i am thinking 48v and DM542 drivers but maybe there are better available?

for the controller i am thinking the mesa 7I96 because it seems cheap and pretty good from what i have read

spindle. i don't really know with this one, i have read some good things about the G-Penny 2.2kw one (https://www.aliexpress.com/item/32253760001.html?spm=a2g0o.cart.0.0.3f5b3c00pATS93&mp=1) it seems cheap ish and gets pretty good reviews. at the same time i don't know how good it really is so maybe someone can recommend me something better.

ohh almost forgot. i plan to cut mostly aluminium and some occasional Delrin

let me know if you need anymore details thanks for any advice in advance Tank!

JAZZCNC
20-11-2020, 09:15 AM
Your wasting your money buying this or any other Workbee type machine design if your wanting to cut mostly cut aluminium, it's just too weak to do any kind of decent job cutting aluminium unless you plan to scratch it away.

The spindle and the 7I96 are ok but you do realise the 7I96 is LinuXCNC only.?

tankproof2
20-11-2020, 12:28 PM
ohh ok, do you have any better recommendations? the only reason for the work bee was cost, if there is a better frame for around the same price i am all ears.

with the 7I96 i know is linuXCNC is this a bad thing? it was what i am planning to run (i know nothing about cnc soft where) as i have heard good things but am I wrong?

Clive S
20-11-2020, 12:45 PM
ohh ok, do you have any better recommendations? the only reason for the work bee was cost, if there is a better frame for around the same price i am all ears.

with the 7I96 i know is linuXCNC is this a bad thing? it was what i am planning to run (i know nothing about cnc soft where) as i have heard good things but am I wrong?

The Mesa 7196 is a very nice board but it does not have 0-10v output for a vfd / spindle the 7i76e does they are both ethernet connected.

Dean is correct have you actually calculated all the extras to get a working machine. For ali you would need 3.2Nm motors and a 2.2kw spindle and vfd.

What is your top budget ?

Don't buy any electrics until you know what you need.

tankproof2
20-11-2020, 12:58 PM
so my budget is somewhere around 1200£ (i know its low) at the moment what i have listed above comes to 1300£ ish which is ok. i didnt know abut the 7i96 not having 0-10v and the 7i76e is quite abit more expensive maybe i will go with an Arduino based system (any recommendations)? i was thinking the 60BYGH401-03 as they have plenty of power and seem pretty cheap and the 2.2kw spindle from G-Penny

JAZZCNC
20-11-2020, 11:59 PM
ohh ok, do you have any better recommendations? the only reason for the work bee was cost, if there is a better frame for around the same price i am all ears.

with the 7I96 i know is linuXCNC is this a bad thing? it was what i am planning to run (i know nothing about cnc soft where) as i have heard good things but am I wrong?

Regards an alternative kit then NO there isn't any that can do this at this money, why.? Because it's impossible for anyone(Even the Chinese) to make money and provide the correct components and a frame strong enough for cutting aluminum correctly at that money.

To cut aluminum properly with correct feed rates, depth of cut (DOC), and give a good surface finish requires a strong machine, which uses linear rails, ideally profiled linear rails, Also ball-screws with correct end bearings. The frame and Z-axis need to be very rigid to handle the vibrations, steel or at least heavy-duty aluminum profile are required.
The WorkBee or any of these Shapeoko type machines with their flimsy frames using narrow profile sections running on Rubber V- bearings with elastic bands for linear motion are simply a waste of time. Putting ball-screws on them is like putting lipstick on a Pig.

Now I know you will have seen videos of them cutting Aluminium, but what they are not telling you or showing you is the effect this is having on the machine long term. Often they are also not telling you how long it takes scratching away at it with 0.25mm DOC. They are also not telling you how it hammers the machine or the shitty finishes they get if they try to take anything like correct DOC etc.

These machines seem cheap but they nearly always end up costing you more in the long run for a number of reasons.
#1 You'll throw money at it to upgrade the frame in an attempt to combat the weakness's but this is folly because you can't make a silk purse out of a Sow's ear. The frame is junk.!
#2 You'll upgrade the Electrical in an attempt to give it more guts, this is pointless because the frame can't handle more power.
#3 You'll try to upgrade to linear rails to get rid of those pain in the arse V-bearings, again pointless due to weak flimsy frame.
#4 You'll upgrade the elastic bands to ball-screws, pointless because the frame is junk so the extra resolution and accuracy is wasted.!!

Hopefully, a theme is appearing now..? . . .The frame is the foundation of any good machine and if it's weak then anything you upgrade or attach to it in an attempt to make it better is wasted money. These frames are Junk and all of the components are inferior or weak.

The best advice I can give you is to save your money and build something yourself from steel/aluminum and with the correct components. Or if you haven't got the tools, time or ability to self build then wait a little longer and save up and have someone like my self build you one.

I promise you this, if you buy one of these WorkBee's then you will regret it long term. They are great for learning on if cutting woods etc and often quickly outgrown but they are useless for cutting aluminum and will disappoint you quickly.


Clive answered the Linux CNC questions. But again I'll warn against going the cheap route on controllers like the Arduino or GRBL setups. They will be limiting and frustrating for a first-time builder.
End of the day if you want to do CNC successfully you can't cut corners or do it on the cheap. It's THE BIGGEST MISTAKE new builders make and ALWAYS ends up costing more long-term or worse puts people off CNC altogether.

tankproof2
21-11-2020, 01:26 AM
hmmm OK thanks, i am fine building a frame from scratch and should have most of the tools, but i just dont see how i can make it anywhere near the price of the workbee frame. i have around 1200£ total budget and so far have about 600 in electronics only leaving 600 ish for the frame. is 600 doable for a diy frame or its it going to be significantly more?

Kitwn
21-11-2020, 02:14 AM
One route you might take is to concentrate your funds on the mechanical hardware to begin with, build a solid frame and use appropriate motors and drivers as jazz suggests, but get started using a cheap controller using Linuxcnc on an old windows XP era compute with a parallel port if you can find one gathering dust and a cheap breakout board. This arangement is cheap enough to consider it expendable and you will be able to test your machine while choosing your preferred controller and saving up the cash.

Linuxcnc can be a bit daunting if you want to add bells and whistles but for a vanilla set-up it's very easy to get going using the included wizards.

tankproof2
21-11-2020, 02:17 AM
Yes ok, I can see the logic in that, but just how much £££ do I need to make a good frame? Is 1200£ even enough?

Kitwn
21-11-2020, 05:33 AM
I don't know the cost of steel in dear old Blighty, but you're looking for RHS (rectangular hollow steel) prices. Here in Australia you could buy an awful lot of it for the equivalent of 600 quid but we dig it out of the ground over here so it might be cheaper! Aluminium on the other hand costs an arm and both legs. I built my machine from steel scavenged off the local tip but that is not the recommended source. Other UK forum members will know more about the likely cost than me.

There are several build logs on the forum which show good designs for welded frames (mine is NOT one of them). If you can already weld, brilliant. If you can't, it's easy enough to do an adequate job and a cheap welder is adequate. You are not building the Forth Bridge and some fairly scrappy looking results will be good enough. You can hide all sorts of sins with a grinder, car body filler and paint. have a look at the pictures in post #5 of the following thread for the proof of that!
http://www.mycncuk.com/threads/13904-Kit-s-Machine

With a steel frame and gantry and a low cost, if temporary, controller you should expect to have most of your immediate budget available for the mechanical components of rails, ballscrews, belts and pulleys etc. and the motors, drivers and power supply plus spindle and VFD.

One very important way you can save money is to consider if you can reduce the cutting area you WANT to build to the cutting area you NEED to build.

Clive S
21-11-2020, 10:13 AM
Yes ok, I can see the logic in that, but just how much £££ do I need to make a good frame? Is 1200£ even enough?

Don't get despondent. This is a good forum and you will get help.

But first try and help yourself by reading some of the great build logs on here, there are plenty on them.

Draw the frame up in CAD and ask for criticism. You will need to lean CAD anyway.

Linuxcnc with a P/port is very doable and is free, the BOB (breakout board) £5-6 on ebay. That alone will save you a chunk on money. For a simple basic machine linuxcnc can be set up in 15 mins.

But don't buy kits of part as they are never matched up. We can point you to the best places to buy the rails ball screws etc.

Start with the frame.

Doddy
21-11-2020, 08:13 PM
Just consider that many of the accessible online metal stores factor in delivery on their prices. Talk to a local supplier - you might be surprised. Also if you happen to be passing any fabricators it might be worth enquiring (I approached a fencing fabricator and they knocked up (welded) a 100x100x4 box section top-frame for a bench, 1600mm x 750mm for a ton... which I thought was pretty good, and flat to less than a mm (as best as I could measure). Also, when sourcing Argon for welding I did speak to a one-man band who showed me around his workshop - a bit of a chat suggested I could buy steel from him cheaper than the usual online stores. Lastly, I bought a load of 100x50x5 box section, a convenient 1.6m long from a fabricator off eBay - was only 20 miles to collect. 6 months later I found similar for sale 20 miles in the opposite direction - turned out they'd bought from the first guy. Keep your eyes open. If you can weld, then you can build a frame pretty cheaply.

JAZZCNC
21-11-2020, 09:29 PM
If you find your local Steel stockholder you'll buy 80 x 45 x 4mm wall in 7.5mtr lengths for about £60+vat. Depending on size 1 or at most 2 lengths will get you the base frame.
For the aluminum for the Z-axis and other areas of the machine, If you have any local engineering places nearby it's worth calling in and asking if they have an offcuts bin. Often what they call scrap pieces we call a Z-axis and they will sell you it at scrap value or if you drop on right bloke a few pints.
Drop on the right place and you might get steel off cuts their too.?

With £1200 it's just about doable to build a decent machine if you are careful and don't waste money buying the wrong stuff. Like has been said stay away from any electronics kit as they are nearly always made up of rubbish and poorly matched.

Linux CNC with a BOB will get you going cheaply like as been said and then it opens up a whole world of expansion if you move to Mesa, it will also open up a whole world of head-scratching as well depending on your skills and temperament learning to speak all thing Linux CNC but to kick you off cheaply it's perfect.

The secret to the successful building of a good machine is to NOT RUSH or BUY ANYTHING and always ask before buying because often someone will point you to a cheaper or better option.

If you take the Build route then the first thing to do is start a Build thread, even before you lay paper to pen, and ask ALL your questions in this thread. Don't start new threads asking questions because they get lost with time, keeping all your questions in one place makes it easier months later when your looking for reply. It also keeps your thread high on the trending list where you are more likely to get replies.

Good luck and don't waste money on those rubbish Kits as you will regret it.

tankproof2
21-11-2020, 11:57 PM
Ok, my foot is off the buy pedal.

i have looked though this forum and see 2 ways of doing it. 1 steel welded frame, 2 Epoxy Granite my question whould be, which is the best/ most cost effective? for a 1.2 x .75m machine.

i will start a build thread now and get cracking on the cad.

thanks for all the help, Tank.

JAZZCNC
22-11-2020, 10:05 AM
Ok, my foot is off the buy pedal.

i have looked though this forum and see 2 ways of doing it. 1 steel welded frame, 2 Epoxy Granite my question whould be, which is the best/ most cost effective? for a 1.2 x .75m machine.

i will start a build thread now and get cracking on the cad.

thanks for all the help, Tank.

Ok, that's easy, Steel is the better and cheaper choice for a machine this size. Why.?

Epoxy granite would be the stronger machine but would cost far more money by the time you have built a substantial mold for it and bought the materials, then you have the weight of the thing, it would be VERY heavy.
Then you have to consider the machine design.! Moving gantry or Fixed.? Epoxy granite would require you to build a fixed gantry otherwise you'll be into BIG and expensive motors to shift all that heavy mass around on a moving gantry machine.
Then you have the size, Fixed gantry would require roughly 2x the area for one of the given sizes.

The best combination is a steel frame with the rail surfaces epoxy leveled to give you better accuracy with the least hassle.

When you are looking at builds pay attention to those that put the rails on high sided frames with the gantry sat directly onto the carriages. This is the stronger design for your needs with cutting aluminum.
If you want a good example of what can be done with basic tools then check out Joe's build. There is many other's similar as well which use this style of the frame design and very well made.

tankproof2
22-11-2020, 05:18 PM
Ok i will go ahead with steel construction, sorry i wasn't able to find Joe's build could you please send me a link, Tank

Clive S
22-11-2020, 07:32 PM
Ok i will go ahead with steel construction, sorry i wasn't able to find Joe's build could you please send me a link, Tank

https://www.youtube.com/playlist?list=PL1FIADAKba_uTgFU5qqS3i705fuSogBXT

JAZZCNC
22-11-2020, 08:24 PM
Ok i will go ahead with steel construction, sorry i wasn't able to find Joe's build could you please send me a link, Tank

http://www.mycncuk.com/threads/4513-3-Axis-CNC-router

tankproof2
26-11-2020, 10:26 PM
Ok, so i have done some research and come to some conclusions. but i have a few questions.

i have found multiple options for a few things and would like to ask which is best


spindle- they are all around the same price but with different vfds but which is the best?

https://www.aliexpress.com/item/32253760001.html?spm=a2g0o.cart.0.0.23223c00DrQIm1&mp=1
https://www.aliexpress.com/item/32985816072.html?spm=a2g0o.cart.0.0.23223c00DrQIm1&mp=1
https://www.aliexpress.com/item/4000586159483.html?spm=a2g0o.cart.0.0.23223c00DrQI m1&mp=1



steppers i am thinking nema 23 and these are the options i have found which is the best?

https://www.welectron.com/JMC-iHSV57-30-18-36-Integrated-Servo-Motor (this one comes with integrated drivers but is about the same cost as the other with a CW8060 driver)
https://www.cnc4you.co.uk/Stepper-Motor/Nema23-4Nm/Stepper-Motor-4Nm-60BYGH401-03-Nema23



drivers-

i am thinking of going for a way over kill driver to give me head room for new/ more powerful motors

options are the cw8060 https://www.aliexpress.com/item/612746616.html?spm=a2g0o.productlist.0.0.a2a0d498d ylNMm&algo_pvid=83fd672d-8386-4796-b608-7750718233eb&algo_expid=83fd672d-8386-4796-b608-7750718233eb-1&btsid=2100bdd716063201660734410e115b&ws_ab_test=searchweb0_0,searchweb201602_,searchweb 201603_

or cheap out and get some https://www.aliexpress.com/item/32917113418.html?spm=a2g0o.cart.0.0.23223c00DrQIm1&mp=1

my question is what is the best cheap stepper right now?

as far as voltage goes i am thinking 48v but is this too high?

JAZZCNC
26-11-2020, 11:40 PM
Ok well the first spindle is the better choice because of the VFD, It's made by Huanyang and is well tested on 10,000's of machines, the other two are copies and lower quality, that said even the huanyang isn't the best quality in the world but I personally have fitted 100's with less than a handful of issues so wouldn't hesitate to fit one or recommend buying one.
The Black one I've only fit on a couple machines and wasn't impressed with them, the white one I've no experience other than I know someone who had one and it blow up after 7 months.
The spindles are all the same. One other thing to mention is the water pump.! These pumps included in the kits are 230V Mains powered and DONT have an earth which isn't cleaver in a submersible pump IMO. I won't fit them.!

Motors:
The first motors with intergrated drives are not steppers they are DC servo motors. Never used so can't comment but 180W isn't a lot with only 48Vdc and won't suit a large machine.

The second motor is a run of the mill stepper, nothing special.

Drives:
The CW8060 are not very good drives at all and certainly NOT going way over kill.? 80Vdc drives are what you will need for a decent sized machine to get the higher feeds you'll want.

The cheaper Dm542 are ok for a small machine but are limited on the Max voltage at 50vdc, for a large router like what your planning then you'll want to be running your motors with around 60-65Vdc to get the best speed and torque from them.

Now personally I wouldn't fit any of these because they are basiclly OLD technology, Newer Closed loop motors with Digital drives are much better and won't cost much more money.
Also look for drives that provide AC input and it will save you the trouble of building a DC power supply and a little money.

However, why are you even looking at buying this lot when as far I can see you haven't even decided or designed the machine yet.?
You are a long long way off needing any of this and while it's tempting to buy so you can test on bench all your doing is wasting warrenty and they will learn you very little.
Also, without knowing the Mass etc of the gantry you could easily buy the wrong size motors/drives.

Again I'll advise you to NOT BUY ANYTHING and say go do more research on the motors/drives and why voltage is very important. But only so you have a better understanding of why getting this part right is so important and not so you are better armed to buy now. Only buy when you need or close to needing them.

CNCRY
27-11-2020, 12:39 AM
Hi Jazz - hope all is good. Sorry to thread hijack, just read your comment about the 230V pump - while running mine today I remembered I'm still using one of those potential death traps with no earth submerged in coolant! From what I can tell (no details with it) its probably 3000L/Hour flow rate .
Do you recommend a better 230V pump or 12/24V versions? Thanks
Ryan

tankproof2
27-11-2020, 12:45 AM
Ok thank you that was very helpful, i will do more research, as far as the motors can you recommend me any closed loop steppers that are cost effective? i am still planing the build but looking in to maybe buying a used/ ebay custom steel frame so just looking for how much steppers ect will cost me so i can price it all out

thanks again Tank

tankproof2
27-11-2020, 02:07 AM
i have found these steppers here (https://www.omc-stepperonline.com/ye-series-1-axis-closed-loop-stepper-cnc-kit-4-0-nm-566-56oz-in-nema-24-motor-and-driver.html) they are closed and not to expensive, are they any good?

JAZZCNC
27-11-2020, 05:29 PM
i have found these steppers here (https://www.omc-stepperonline.com/ye-series-1-axis-closed-loop-stepper-cnc-kit-4-0-nm-566-56oz-in-nema-24-motor-and-driver.html) they are closed and not to expensive, are they any good?

They are ok but again they are only 50V drives and this will limit the speed/torque.

But today could be your lucky day.!! . . . I've just received a shipment of 50 sets of Lichuan Closed-loop steppers. 4.5nm and 5.5Nm that use AC volatge. A large number of these are allocated to machine builds but I have about 10 sets spare that I would be willing to sell.

https://www.aliexpress.com/item/1005001370469790.html?spm=2114.12010612.8148356.45 .74663421I66r5w

I also have Ethernet controllers from CNC DRIVE that I would sell. I have AXBB-E and UC300ETH with the UCBB Breakout board. Also can provide UCCNC license files at extra cost but lower than you'll pay elsewhere.

In a few week's time, I'll also have 2.2Kw spindle kits. Similar to what you were looking at with Huanyang VFD etc.

PM me if you are interested.

JAZZCNC
27-11-2020, 05:31 PM
Hi Jazz - hope all is good. Sorry to thread hijack, just read your comment about the 230V pump - while running mine today I remembered I'm still using one of those potential death traps with no earth submerged in coolant! From what I can tell (no details with it) its probably 3000L/Hour flow rate .
Do you recommend a better 230V pump or 12/24V versions? Thanks
Ryan

To be honest I just use 24Vdc pumps that they use for solar heating, they are cheap and safe. Plenty of them on Ebay.

tankproof2
27-11-2020, 05:43 PM
ohh awesome will pm now

JAZZCNC
27-11-2020, 09:26 PM
ohh awesome will pm now

Sorry for delay I was at work when posted that and didn't see your post or PM until got home, but PM sent now.