eBay router

[cncmystic]

Hi JAZZCNC
I have been lookig at the same CNC router on Ebay and wondering about the quality of it, so your response to this question was very useful for me
I note you say that you build machines for people..
I am interested to get an idea from you as to what you would charge for a similar sized machine, (say 1000 x 1000 or 1220 x 1220 ie half sheet) that would be sturdy enough and suitable for milling aluminium.
Many thanks

Ok well I'm going to answer this but I want to make it clear because as most of you know I build machines for people that in no way what I'm about to say is said to pull this machine down for my own purposes because I really don't need to. Neither is it intended to say anything about the guy or company building them as I don't know him at all.

What you need to do is look carefully at the machine and ask some questions about it.!

#1 The frame is a welded construction which at first might seem good, but as any on here who have welded a frame will tell you they always twist and move. Also, it's critical to accuracy that the surfaces the rails fasten onto are exactly on the same horizontal plane and vertical planes. This is why we go to great lengths machining or using methods like epoxy leveling.
This machine as NONE of this done to it. Add to this that the 75mm with 3mm wall thickness isn't that strong and being thin-walled it resonates quite a lot which again affects quality of the cut.

#2 Gantry is a very weak affair that's better suited to a plasma machine, just.!!... and again no signs of any attempt to make sure it's flat and not twisted. Plates and connections to ballscrews and key areas like Z-axis are flimsy thin things.

#3 The motion control side is done from the PC with a £5 breakout board. From what I can see he's using commonly used refurbished Dell PC's, which are actually the same ones I use with Ethernet controllers.
If so then I can tell for sure that the parallel port on these is very flaky and I use exactly the same setup for testing and setting up machines with the same KKo1 board and they crash and lockup for fun. So bad that they won't even pass the Linux CNC latency test for using with a parallel port.

#4 Nema 34 motors are just wrong choice for a machine this size and I'd put a wager on it they are run on low voltage to boot. NEMA 34 motors need lots of voltage to get speed. Thou he does use 16mm pitch screws which will offset this to some degree, but still not a good choice for several reasons.

#5 The rails are the round type and the cheap variety, in fact looking closely at the components like ballscrews and BK/BF bearings I believe they are the lower quality units that come out of China, Not all ballscrews and bearings coming out of China are the same quality. Again many on here who have built and bought from China will confirm this.
I've spent a lot of years using various suppliers in China and I'm pretty sure these are the lowest spec available and is how they can sell these machines at this price. Which is ok but they wear out quickly and get sloppy fast and when fitted to a machine that isn't built very accurate to start with these all compounds to give a not so accurate machine.!

#6 The Z-axis is a weak affair fastened to flimsy plates that extend too far at 170mm with a heavy spindle on the end. The end result will be vibrations at the tool which is exactly where you don't want it.!

Other than these things then it's fine for light hobby use provided you are aware of its shortcoming and low-quality components. Oh and the shitty parallel port which I wouldn't trust to run my kettle.!

[Chip Owner]

Hi JAZZCNC
I have been lookig at the same CNC router on Ebay and wondering about the quality of it, so your response to this question was very useful for me
I note you say that you build machines for people..
I am interested to get an idea from you as to what you would charge for a similar sized machine, (say 1000 x 1000 or 1220 x 1220 ie half sheet) that would be sturdy enough and suitable for milling aluminium.
Many thanks

The machine on ebay cuts aluminium fine, all day long, despite being designed for cutting MDF. Nice clean cuts even in thin 1050 sheet.

In comparison to others in similar price bracket, i.e. 60/90 chinese routers, Xcarve and so on, it's far better.

Could the machines be better, yes, could the finish be better, yes but for around £2500k after some basic mods they work well.

[cncmystic]

Hi Chip Owner
Thanks for the feedback
What are the basic mods you are referring to ?
Is that the machine you are using ?
You are referring to thin 1050 sheet. Would it be OK to mill say 25mm aluminium parts ? (understandly with the appropriate depth of cut, plunge depth per pass and feed speeds)?
When you say ... the machine could be better, what parts are you referring to.
Many thanks
_________________________________________

The machine on ebay cuts aluminium fine, all day long, despite being designed for cutting MDF. Nice clean cuts even in thin 1050 sheet.

In comparison to others in similar price bracket, i.e. 60/90 chinese routers, Xcarve and so on, it's far better.

Could the machines be better, yes, could the finish be better, yes but for around £2500k after some basic mods they work well.

[Chip Owner]

Hi Chip Owner
Thanks for the feedback
What are the basic mods you are referring to ?
Is that the machine you are using ?
You are referring to thin 1050 sheet. Would it be OK to mill say 25mm aluminium parts ? (understandly with the appropriate depth of cut, plunge depth per pass and feed speeds)?
When you say ... the machine could be better, what parts are you referring to.
Many thanks
_________________________________________

Yes I have one of those machines, ordered just before lock down, I would have liked to visit during the build process but this wasn't an option. Things like all the screw in the rails as mentioned elsewhere, I had to finish drill & tap some of these. Also the cables weren't through the frame tube.

Position of VFD is personal choice.

I've added a galvanized plate across both sides of the bed side to reduce side spill of chips, I've added a similar plate to the rear of the gantry, I'll be adding a 4th to the very rear soon too. I've also added some triangle braces on the Z axis top plate, long term I'll do these properly.

Part way through a vac bed installation as I cut thin sheet and will eventually replace the supplied MDF wasteboard/baseboard with steel.

25mm aluminium parts would be fine, it's all down to bit you use and hold down method.

It doesn't do slow at speeds 300-1100mm per minute it's very noisy. Over 1150mm per minute it's fine. Our current bits allow cutting of 1050 sheet at 1150mm-1300mm - with a nice clean cut requiring minimal cleanup. We're changing to a slightly higher grade on next tool order to increase cutting speeds further.

[cropwell]

. Our current bits allow cutting of 1050 sheet at 1150mm-1300mm - with a nice clean cut requiring minimal cleanup. We're changing to a slightly higher grade on next tool order to increase cutting speeds further.

I am intrigued to know what cutters, speeds, feeds and coolant you are using. I sometimes cut 1050 sheet (2 and 3mm thick) and it's the gooiest material I have found apart from some plastics.

[Chip Owner]

I am intrigued to know what cutters, speeds, feeds and coolant you are using. I sometimes cut 1050 sheet (2 and 3mm thick) and it's the gooiest material I have found apart from some plastics.

Zero coolant, it's not needed. Correct tool, feed and speed created the right chip dispersing heat, a mild blast to further help disperse the chips from a low pressure hydroponics pump is the only external addition.

I use bits supplied by LKHtools.co.uk

[JAZZCNC]

The machine on ebay cuts aluminium fine, all day long, despite being designed for cutting MDF. Nice clean cuts even in thin 1050 sheet.

In comparison to others in similar price bracket, i.e. 60/90 chinese routers, Xcarve and so on, it's far better.

Could the machines be better, yes, could the finish be better, yes but for around £2500k after some basic mods they work well.

Hi Chip,

Sorry but while it may cut aluminum there's a huge difference between scratching and cutting and I now just from looking at the design and build quality that the finish quality and cutting depths etc must be compromised when cutting aluminum.
The gantry is so flimsy that finish quality cannot be great and if any decent DOC was taken it would vibrate like holy hell. Even if using trochoidal (adaptive, i-Machining, etc.) tool paths with constant engagement which take a lower chip load I'd be surprised if the finish wasn't poor because of the high feed rates causing vibrations in the frame and gantry which transfer to the tool.

I know it's not what you want to hear me saying, esp as I suspect with you being located in Cumbria that you might have something to do with this company. But I've built enough machines to know what it takes to cut aluminum properly with a good finish and this machine isn't strong enough IMO. . . . And I'm not even bring rail parallelism and accuracy, etc into the argument which again has a huge impact on finished work.!!

[cncmystic]

Hi Chip,

Sorry but while it may cut aluminum there's a huge difference between scratching and cutting and I now just from looking at the design and build quality that the finish quality and cutting depths etc must be compromised when cutting aluminum.
The gantry is so flimsy that finish quality cannot be great and if any decent DOC was taken it would vibrate like holy hell. Even if using trochoidal (adaptive, i-Machining, etc.) tool paths with constant engagement which take a lower chip load I'd be surprised if the finish wasn't poor because of the high feed rates causing vibrations in the frame and gantry which transfer to the tool.

I know it's not what you want to hear me saying, esp as I suspect with you being located in Cumbria that you might have something to do with this company. But I've built enough machines to know what it takes to cut aluminum properly with a good finish and this machine isn't strong enough IMO. . . . And I'm not even bring rail parallelism and accuracy, etc into the argument which again has a huge impact on finished work.!!

Hi Dean
I put a post up in reply to one of your posts regarding this a few days ago, but I don't know if you have seen it.
I want a CNC router, say 1000 x1000 or preferably half 4x8 ft sheet so that in two steps, I could route/mill a 4x8 foot sheet when needed
If I did want to build one myself with the main purpose of routing aluminium sheets and milling alumium parts, what would your suggestions be for me to build one ? Ie are there any plans out there that you would recommend to base my build on ? I do have access to a manual mill and lathe (Warco ones)
Alternatively, I noted in one of your posts that you also build machines. Would would it cost for you to build me such a fit for purpose machine ?
Many thanks

[JAZZCNC]

Hi Dean
I put a post up in reply to one of your posts regarding this a few days ago, but I don't know if you have seen it.

No sorry didn't see it but I am very busy so only skimming forum every other day so must missed it.

If I did want to build one myself with the main purpose of routing aluminium sheets and milling alumium parts, what would your suggestions be for me to build one ?

Well, this is the issue, profile cutting thin (2-3mm) aluminum sheet isn't that taxing provided your using correct tools and feeds which is why these weaker machines can do that. However, cutting or milling thicker parts with a good rate of material removal with good finish quality and accuracy is a completely different story and requires a very sturdy machine which is why I know these machines cannot handle it or do a very good job.

As the machine gets larger then it gets even harder so really you need to decide what's most important to you, sheet cutting, or milling.? Because two very different machines are required. Large machines don't lend them selfs to milling aluminum very well unless heavily built so be prepared for it to cost more money.

Ie are there any plans out there that you would recommend to base my build on ? I do have access to a manual mill and lathe (Warco ones)
Alternatively, I noted in one of your posts that you also build machines. Would would it cost for you to build me such a fit for purpose machine ?
Many thanks

Search the forum is my advise and look at machines with high sides and gantry sat directly on the rails. Boyan built a massively strong machine which is IMO OTT for most things but will happily Mill aluminum and steel to a lower level.

I don't know of any plans that are any good.!

The question I would ask your self is do you really need to MILL large aluminum parts that won't fit on a smaller machine which is much easier and cheaper to build. One machine that can do it all and to a good standard is very difficult to achieve and not cheap.

If you are serious about me building a machine then contact me directly via PM giving me some idea of your budget and I'll see what I can offer you.

[cncmystic]

Hi Dean ..
You are right in that CNC routing and CNC milling are two different things, though they do overlap a certain amount.
I am probabbly being too generic in my requirements.
I have a requirement to mill thicker aluminium such as 25mm or thicker but not at 1000mm x 1000mm, but probably not more than 400 mm x 400 mm.
I do have a requirement to route other materials like wood, ply, perspex, etc... at around a half 4ft x 8ft sheet so that I could do a full 4ft x 8ft sheet in two separate operations.
I suppose I really should be looking at two machines for that rather than one machine to do it all
I do have a warco WM16 manual mill that I am looking to convert to CNC but the throat size (as with most mills of that gender) is limited to about 140mm and with a bit of clever work with spinning the part around 180 degrees one could cut the part in two operations and perhaps achieve a part of up to around 250mm width which falls short of my ideal 400mm.
What are your thoughts about which direction I should really be looking at to solve my requirements
Many thanks Dean

No sorry didn't see it but I am very busy so only skimming forum every other day so must missed it.



Well, this is the issue, profile cutting thin (2-3mm) aluminum sheet isn't that taxing provided your using correct tools and feeds which is why these weaker machines can do that. However, cutting or milling thicker parts with a good rate of material removal with good finish quality and accuracy is a completely different story and requires a very sturdy machine which is why I know these machines cannot handle it or do a very good job.

As the machine gets larger then it gets even harder so really you need to decide what's most important to you, sheet cutting, or milling.? Because two very different machines are required. Large machines don't lend them selfs to milling aluminum very well unless heavily built so be prepared for it to cost more money.





Search the forum is my advise and look at machines with high sides and gantry sat directly on the rails. Boyan built a massively strong machine which is IMO OTT for most things but will happily Mill aluminum and steel to a lower level.

I don't know of any plans that are any good.!

The question I would ask your self is do you really need to MILL large aluminum parts that won't fit on a smaller machine which is much easier and cheaper to build. One machine that can do it all and to a good standard is very difficult to achieve and not cheap.

If you are serious about me building a machine then contact me directly via PM giving me some idea of your budget and I'll see what I can offer you.