Has anyone got any experience of SheetCNC or UK-DIY CNC?

[OceanMachine]

First post, sorry if this is in the wrong forum?

I live in the UK and have been looking at large format CNC machines, preferably capable of cutting 8' x 4' sheets of Plywood, MDF, etc.

I found SheetCNC, a UK based company that makes such a machine (i.e. the Mk3 version), but I am struggling to find forums or any other user experience information of whether this machine is any good or what it is like dealing with this company?

SheetCNC (http://sheetcnc.co.uk/) designed the machine, but have outsourced the making/supply of the kits to UK-DIY CNC (https://www.uk-diycnc.com/).

This machine has chain drives, and they say accuracy concerns are unfounded (http://sheetcnc.co.uk/faqs/) and it seems to have a lot of capability, but I can't see much info out there other than the videos they provide (which look impressive) and so I am struggling to know whether this is something worth going for...

Here is the manufacturer information about the machine specs: http://sheetcnc.co.uk/the-machine/
As well as the FAQs addressing accuracy and backlash questions:http://sheetcnc.co.uk/faqs/

Does anyone have any experience with them, or know whether the spec seems good for the price, or anything else noteworthy about the spec, etc?

Thanks in advance, and sorry if I posted this in the wrong forum!

[m_c]

The things that stand out, are the fact it's made from MDF, and it uses v-bearings running on angle iron. Neither of which are likely to create a reliable machine that doesn't require regular tweaking to keep running well.

Chain drive wouldn't really bother me, other than it's going to attract a lot of dust.

I'd also guess at the rapid speeds they're claiming, it will never actually reach them, or it'll shake itself apart with the accelerations involved.

[reelman]

If your looking for a machine for production runs then I would speak to jazzcnc on this forum he builds robust machines to order. Look at the thread named My new machine - Guess the make! hope this helps you make the right choice as it very easy to make the wrong one

[JAZZCNC]

If you are serious about CNC and want it to last for years then It's everything in a CNC you don't want, and if your thinking to use this for a business then it will be your worst nightmare.

But if you just have limited use for it and don't plan to use it for more than a few years, also don't mind constantly tweaking and adjusting it to hold what would be considered very poor tolerances by a properly built router then I still wouldn't recommend buying it.!

They never tell you about the constant tweaking and adjusting which will be needed to keep it holding pretty rubbish tolerances.?
The linear rails which it doesn't use but rather in place uses cheap V-bearings running on soft angle iron edges quickly wears and gets gummed up with crap causing all kinds of trouble like binding and jamming, esp at higher feeds when torque drops away as the rpm's rise.

The chain drive system is strong but clunky and again as debris gets into it is prone to jamming. As it wears and stretches from the constant rapid acceleration and direction changes it will need constant adjustment and cleaning.

The Z-axis, which the most important area of the machine is a joke, made from threaded rod and angle iron it will chatter like crazy in anything harder than butter.

Then you have the MDF/Plywood frame which will shapeshift more than characters from deep space 9 all mixing into the soup..!!

There's a reason 8x4 machines cost what they do and trying to cut corners just leads to frustrations, believe me, I've built machines for people who have bought these kinds of kits or attempted to build their own and wasted lots of time and money chasing all the nightmare that goes with them before giving up.!! .. . . Avoid like the plague is my advice.

[Neale]

My first router was built from MDF. It was the JGRO design, freely available via a google search. Designed to be built with little more than hand tools, although I did make a few small detail improvements by 3D-printing some bits and pieces. Cutting area, from memory, must have been around 600x450mm. I can echo JazzCNC's comments - it meant a constant round of tweaking and adjustment, pretty much every time you used it. In the end, the gantry was sagging so much that I had to shim out the motor mounts to get the spindle anywhere near vertical. I did some useful work with it, but the idea of long-term accuracy and stability from something built from a material with the structural integrity of cold-rolled cow dung is a bit laughable. My Mk2 machine is welded steel - that was one lesson learnt!

I wouldn't ever say that you shouldn't build a machine from MDF, but be aware of the limitations. It has the great advantage that it can be cheap, so when you throw it away and replace it with something better, you haven't lost much! But I'm not sure that I would pay big money for someone else to build one, and the idea of it being rigid enough for 8x4 operation seems unlikely...

[OceanMachine]

FIrstly, thank you very much for taking the time to reply, and sorry for not replying sooner, I typed out a reply last night on mobile and lost the text before submitting it.

So it sounds like I would probably face a bit of buyer's remorse if I were to go down that route, and I need to alter my expectations based on my budget of 4-5k.

I think I am a bit too attached to the idea that I might be limiting myself if I get something that is too small to cope with some of the projects I was thinking of looking at. I am therefore thinking of other machines I was looking at, I understand that the Maslow system suffers a lot with accuracy near the edges of the cut larger cut areas, and I was thinking that other machines were either out of my budget or would limit what I can do.

I was also looking at things like the shapeoko or oozenest kits, but was put off by the smaller bed sizes so am not really sure what my options are. I realise that I will probably be cutting the larger stuff more rarely than the more medium size pieeces, but I still wonder whether there are any machines that could perhaps cope with larger sheets perhaps doing multiple cuts - moving the sheeet after doing the first cut to complete the piece. Is this a more reasonable thing to think of? Are there any kits that might fit my needs that could perhaps fit that useage scenario?

I don't want to regret my decision by buying a machine that gives me constant headaches, but also don't want to limit my capabilities too much. I am not looking at doing production runs or anything yet, I am just a hobbyist for now, but would not be adverse to selling pieces if I get that far. I am a software engineer and am interested in CAD so it seems like the perfect type of machine to marry all the things up that I am interested in, working them into something I can get into.

I don't mind putting a 'kit' together (or more likely a list of component parts), given the right budget, but would want to make sure I am getting something that I don't instantly regret, and that would put me off developing it further.

I saw the Snapmaker (2), but that seems like it might be a bit of a jack-of-all-trades and not especially good at either CNC or 3d printing, so again was a bit put off. I also saw the recently announced xcarve pro, but that seems like a hassle to get to the UK, is probably out of my budget too, and therefore not really something worth considering at the moment.

I appreciate the advice, and saw especially JAZZCNC and the thread that was mentioned about building machines for people who try to cut corners leading to frustration, but just starting out I can't jusify the 10-15k+ budget of what seems like the start of reasonably capable machines just yet. So is there anything that I can do that may give me the best of both worlds - not a full sheet machine, but capable of cutting larger parts with multiple cuts, perhaps, that would not make me regret the investment straight away?

Given all the experience on this forum, what would you do if you were just starting out, and could look back and wish you had gone in a certain direction given what you know now?

Am I being completely unrealistic in what I am wanting to get for the rough budget that I am consideriing, and I should just give up on that idea and start a lot smaller, first of all? I don't mind putting work in to build a machine from partial kits and other parts, and I am willing to learn but don't really know where to start, given that I am glad I asked about the seemingly 'perfect' machine to a layman, there is always something that seems too good to be true (and usually is), so again thank you very much for steering me away from that decision!

I am in the UK, so it would have to be something available over here, and most of what I see on the market is much more difficult (or almost impossible) to get or much more expensive over here, so appreciate the advice from that point of view. I am lucky to have quite a large space I can use, so that is why I was even thinking of an 8x4 machine in the first place. I see people saying that given the right machine imported from china that you could get a cast iron machine for around 4k, but I imagine that is a complete minefield and support would be pretty much none-existant, so would have to rely on more local troubleshooting. But I suspect that a lot of people will have had some very negative experiences there too, so again would like to hear from anyone who can tell me otherwise!

Once again, thanks very much for the advice, and I am hoping that I can get a general feel for what kinds of machines/kits are out there and any that stand out as being good starting machines that are capable but will not frustrate from day one. Or whether I just need to let go of that idea until my budget can stretch further!

[JAZZCNC]

I appreciate the advice, and saw especially JAZZCNC and the thread that was mentioned about building machines for people who try to cut corners leading to frustration, but just starting out I can't jusify the 10-15k+ budget of what seems like the start of reasonably capable machines just yet. So is there anything that I can do that may give me the best of both worlds - not a full sheet machine, but capable of cutting larger parts with multiple cuts, perhaps, that would not make me regret the investment straight away?

Well, you don't actually need to 10-15k to get a capable machine but you do need a little more than 5k for a large machine like an 8x4. But the question you really need to ask yourself is do you really need an 8x4.?
It's quite possible to cut 8x4 sheets on a 4x4 machine with a little creative cam work. You simply feed the sheet through the machine and using registration markers or dowels etc you can cut the same large part an 8x4 could.



Am I being completely unrealistic in what I am wanting to get for the rough budget that I am consideriing, and I should just give up on that idea and start a lot smaller, first of all? I don't mind putting work in to build a machine from partial kits and other parts, and I am willing to learn but don't really know where to start, given that I am glad I asked about the seemingly 'perfect' machine to a layman, there is always something that seems too good to be true (and usually is), so again thank you very much for steering me away from that decision!

Yes and No.
Yes, it's unrealistic to buy off the shelf an 8x4 machine that will be any good with only £5k, the correct parts alone for a machine this size would nearly come to that.

No, it's not unrealistic to build your own 8x4 with £5k, BUT it's only really possible if you have the experience and equipment plus know where to buy all the correct components from. It's very very easy to get it wrong and many who have tried failed or completely underestimated the work involved or as is often the case not done enough research which leads to buying the wrong components so the costs spiral out of control.

Forget kits, I don't know of any kits that are cheap and worth buying and nearly all those that are anywhere near halfway good usually end up costing the same or more than DIY building by the time you add all the other associated electronics, etc.
Some of the better off-the-shelf kits actually work out more expensive than having one built from someone like me.!



I am in the UK, so it would have to be something available over here, and most of what I see on the market is much more difficult (or almost impossible) to get or much more expensive over here, so appreciate the advice from that point of view. I am lucky to have quite a large space I can use, so that is why I was even thinking of an 8x4 machine in the first place. I see people saying that given the right machine imported from china that you could get a cast iron machine for around 4k, but I imagine that is a complete minefield and support would be pretty much none-existant, so would have to rely on more local troubleshooting. But I suspect that a lot of people will have had some very negative experiences there too, so again would like to hear from anyone who can tell me otherwise!

At the moment the shipping from China alone would cost £4k and yes it's a minefield with near-zero support and machines with electronics which are like a box of chocolates with no lid.!
Also, there are cast iron frames then there's Chinese cast iron frames, the latter not always being a good thing.!
The same is true for the steel-framed machines they produce, There is a thin-walled tube then there is a Chinese thin-walled tube.? until I worked on a Chinese machine I didn't know a large box section could be produced that thin.!

[Kitwn]

There are so many worms in this particular can! I understand your frustration but the first thing you need to decide is what you REALLY want to make. The machine you linked to says it's only good for wood and plastics and not for tools over 6mm diameter. If you can stick to this yourself then some relaxation of your required specification is possible. A big influence on cost is also the cutting area as you've already realised. Do you really need to cut out parts the size of a whole sheet?
Do you want to make decorative bass relief panels, house signs and relief maps of New Zealand (Google 'CNC Nutz' if you do) or parts that need to fit accurately together with minimal hand finishing? This will affect the kind of accuracy you will ultimately need and, as a separate subject but just as important, how much you may want to spend on design software.

Good luck with your journey of discovery and don't be affraid to carry on asking questions.

Kit

[mekanik]

Hi
Welcome to the forum
If you have the time go to the build logs and ingest some, this will give you an idea of what can be achieved and the amount of work involved, it is possible with relatively modest equipment, Joes build is a good example of what can be achieved with a hand held router on aluminium tooling plate(http://www.mycncuk.com/threads/4513-3-Axis-CNC-router) Steel frame is the cheapest option and the welding doesn't need to be perfect to be rigid.
Use the tried and tested Aluminium Profile L shape gantry.
Use the information from the logs to make a start on your CAD drawing and then post it for the guys to have a look.
Good Luck
Regards
Mike

[OceanMachine]

Once again, thanks to everyone for the advice, I am really grateful for how helpful everyone is, and for taking the time to answer my questions! I will be doing a bit more research and will be sure to ask more questions before buying anything!

Dan

[SheetCNC]

Hi everyone. New here. I'm IanB, designer of SheetCNC.

There are lots of good points in the posts above. Here's my tuppence-worth, to add to them.

SheetCNC is one possible answer to the (long) question "I have a business idea that needs a 2.5D 8x4 CNC, but I haven't got a local makerspace, I've tried having my stuff cut at a CNC shed but the QC was terrible, none of my mates has a CNC, and I also know that nine out of ten new business ideas fail so I don't want to spend too much... so how cheaply can I start CNC'ing sheets of plywood/MDF in my own shed?"

Much depends on how many compromises you're willing to make.

We do get a lot of inquiries from novices (because of the price). We always ask inquirers what they want to cut with their CNC, and we turn away 75% of them right off the bat because they're wanting to work beyond the limits of the machine. And we always ask potential buyers to bring a sample of their work and try it on a demo SheetCNC. If there's one thing we don't want, it's disappointed buyers.

Some of the things we like to ask:
Do you want a CNC for an established business that's already doing well? Then we suggest you spend bigger money on something better. SheetCNC might do you for a year or two, but in time you'll grow your business, you'll hit SheetCNC's limitations, and you'll have to buy another machine anyway. So don't go through the grief of setting up two machines with all the downtime that entails.
Do you want to cut metal? Sorry, won't work.
Do you want to cut lots of plastic? SheetCNC can cut plastic, but only slowly because there's no coolant and you need to avoid melting the workpiece. So productivity when cutting plastic is pretty poor.
Do you need cutters bigger than 6mm (excepting for surfacing and reaming)? Not a great idea, because deflections are likely to be excessive. (Chains being stretchier than racks/screws.)
Is intricate 3D work your main objective? Probably better to find something capable of very high accelerations.
Do you want better than, say, quarter-millimetre accuracy when cutting 8-foot plywood sheets? Wow, what are you making?! But sorry, you need a better machine.
Do you need a turn-key installation, that's all set up for you, ready to go? SheetCNC is mechanicals (and motors) only. You'll need to set up a controller, and a vac system, and your own cable runs. So considerable previous DIY experience is essential.

Some of the things we get asked:
Does the MDF warp and sag? No. The small parts are too small to sag. The big parts are bolted tight to lumps of steel, and they don't sag.
Does it need adjusting after initial set-up? In a minor way, yes. You'll need to check chain tensions occasionally, and keep an eye on V-bearing tensions. But it takes seconds to check these things. So it's not fit-and-forget. But it's not a complete PITA, either.
Is the Z-axis a threaded rod? Kind of. It's a 8mm-pitch leadscrew on two brass leadnuts with a basic anti-backlash adjustment.
Does the chain clog? Do the V-bearings clog? We use a SheetCNC for our PhieldBug business. It runs for an hour or two at a time cutting hundreds of complex parts from a single sheet. That's a huge amount of cutting, usually unattended (ahem, insert whistling-emoji here :-) ) and the resulting pile of chips and dust fills a barrel. But it's never come close to clogging and there's never been a need to clear chips from the mechanicals during an operation. Maybe that's a side-effect of being limited to small cutters: they only produce small chips so there's nothing substantial enough to bung anything up.

I hesitate to tell anyone what they "should" do... but I'd suggest that anyone completely new who's looking for a flat-bed CNC might consider seeking out a maker-space - even if that means a substantial journey - and getting some tuition and some experience on their flat-bed CNC. You'll learn so much about CNC, and you'll start to get a feel for the compromises that go into a machine's construction. That'll help you make an informed choice of which of the many machines out there will be up to the jobs that you want to do. Because, when you consider how much money (and time too) you'll be putting into buying and setting up your first machine, the investment of a couple of days working a CNC machine will pay back many-fold.

Best of luck with your search.

Cheers,
IanB.