New router build advice...

[SweetAs]

Im after some advice as I'm not sure where to start. Hope you guys don't mind me asking a whole swathe of questions.

We had planned to purchase a Chinese CNC however this may no longer be an option so I'm thinking of building one instead. I've built a couple small machines but I seem to be hitting a block with a big unit. Extrusion and VWheels seem alot easier lol. The router will be 8 X 4, ideally 5 x 10 would be better as we work alot with 5 x 5 sheets of Birch Plywood but I'll go with what we can get. It's going to be used for MDF and Plywood production type shape cutting as well as 6mm 8 x 4 plywood sheets long sweeping cuts. HDPE, Plywood, MDF, Hardwood, soft wood and Ally machining for signage. The v carved or pocket cut type. I've also got an idea for machining 100mm thick laminated birch Plywood blocks into 3d (2.5d?) shapes.

I've had a read through of the stickies and build logs but there are a couple of bits which are making it difficult for me to price up...

Machine size

What short of frame would I be looking at for the above sizes? 3 X 1.8m would be good enough for an 8 X 4?

Bed/Stand

Does this need to be made from steel? Could I get away with making it from 4x2 with a 40mm MDF top?

Frame

I've not welded since school but reckon I can weld together a frame if I have a bit of practice. Would 80 x 80 x 5mm steel box section work? I picked 5mm to allow for tapping. I'll get a design made up but currently I'm thinking of 3 long sections with 2 end pieces and 4 supports left to right, one every 600mm or so.

Square rails

Will 20mm rails work? I've only been able to find these at 2.7m so does that mean that 8 x 4 is the biggest I can go? I would be looking at Hiwin.

Drive system

25mm ballscrews, was my first thought but again, I'm still learning. Is there is a good quality supplier to get these from in the UK?

Electronics

I'm still learning about this. I've been reading stacks of posts from Jazz to try and get the right balance between cost and performance. Hoping someone could point me in the right direction in terms of specs or reading material. Fully understand I need to get the mechanical design sorted.

Spindle

I'm thinking 4.5kw with a 6kw inverter to run it. This is the sort of spec we were looking at in China. Is this overkill for what we need?

Software

I've seen alot of good to be said for UCCNC so I'm thinking this is where I will be edging towards unless I'm off the mark again.

Budget would be up to £5k but ideally lower if at all possible. Does this sound doable or am I way off the mark here?

Please feel free to correct me or ask any questions you need answering.

[AndyUK]

Square rails

Will 20mm rails work? I've only been able to find these at 2.7m so does that mean that 8 x 4 is the biggest I can go? I would be looking at Hiwin.

Drive system

25mm ballscrews, was my first thought but again, I'm still learning. Is there is a good quality supplier to get these from in the UK?


You can join rails - granted its a pain in the arse, but can be done.

I think most machines of this size will use R&P; but theres been some interesting threads recently about rotating ball nut setups which might be worth looking into.

As always with suppliers, Fred at BST Linear on Aliexpress (https://bstmotion.aliexpress.com/store/314742). Email directly for a quote though.

[JAZZCNC]

Ok straight of the bat drop any thoughts of building from wood as you will regret it and defeats the point in using components like linear rails and ball-screws. It will also cost nearly as much if not more in wood than it would steel and take longer to build.

Next is the 5K. Yes it's just about do-able building your self but you'll need to be careful with what you buy and nearly all the major components will have to come from China.

Regards how to drive it then this needs careful consideration, esp if you have little to no experience because when you get long things begin to get complicated fast.
R&P is often used on large machines but it's the least efficient typicly around 50/60% with more backlash so it needs large motors/drives etc which cost more and needs the most maintenance.
Gearing will be required so you need to factor which method to use and what ratio will be needed to give you the feeds you require and keep the motors in right RPM range to give torque while cutting. Get it wrong and you'll be chasing speed or constantly chasing issues with stalling motors and belts etc.
The setup is simple but needs most maintenance adjusting the backlash to a minimum while at the same time not over tensioning the pinion causing excessive wear.

Rotating ball-screws are far better-regarded efficiency typically around 90-95% and require slightly less power but they come with there own issues, namely screw whip at higher feeds. So again a careful selection of right screw diameter and pitch is required along with motors. Thicker screws whip less but the inertia is a lot more so more powerful motors are required, again more costly. Alignment also requires careful set up so there's more to setting up the machine. The upside is that when it's done it's done unless you have a major incident and skew the gantry up badly, in which case you usually knacker the screws anyway so it's all fubar.!

Rotating ball-nut setup works the best in my experience but these are not something you can easily buy of the shelf and very expensive. So the only option is to build your own which isn't something most people can do unless they have access to a lathe and mill and know how to operate them to hold high tolerances.

Next option and one I'd suggest you consider is using a belt drive.? It gives a combination of Screws and Rack. It's very efficient at around 80% with low backlash and if done correctly can give very close to the ball-screw performance. It still requires gearing to give you the correct feeds etc but with much less hassle than R&P gives regards setup and adjustment.

Regards the rails then 20mm will easily handle the loads etc but 25mm works better on a machine this size and to be honest, the difference in price isn't massive so not worth not using. Highwin Linear rails can be joined easily enough but you can buy them up to 6mtr in length in the UK. From China, 2,9Mtr is about the longest you'll get if using air freight. If you ship them by sea you can get longer lengths but is a pain in the arse and takes longer.

The goal when building a machine this size or any machine, to be honest, but esp at this size is lowering vibrations because they affect the performance and finish also increasing tool wear. So with such a wide machine, the gantry becomes a tuning fork. So a substantial gantry and rail system pays off big time.
Don't let the fact your cutting MDF and Ply fool you, to cut correctly and make machine this size worthy you'll need a strong gantry with a spindle that can handle a good depth of cut at correct feeds. You'll also need a good dust extraction system so factor this into your Budget.!

Regards the spindle then you'll need a Z-axis Motor with a brake otherwise it will fall under its own weight when powered down or strain the motor when at standstill for long periods. These things are all adding to the costs and highlight just how quickly costs can rise.

My Strong advise is to buy NOTHING until you have finalized design to a relatively high level with a full understanding of what building and why you are using those components. If not then you'll just blow money, waste time and frustrate your self daft when things don't work as expected.

[routerdriver]

Machining 100mm blanks might be an interesting challenge.First you need to find long cutters and then you need to be sure of getting them to and from the workpiece without digging a trench.

[JAZZCNC]

Machining 100mm blanks might be an interesting challenge.First you need to find long cutters and then you need to be sure of getting them to and from the workpiece without digging a trench.

Not with the right spindle and design of the gantry / Z-axis. All the machines I build at this size will cut 100mm depth and retract the tool above the workpiece. However, The cutters are expensive and not easy to find. Work holding also becomes a fun challenge.!

[Kitwn]

Next option and one I'd suggest you consider is using a belt drive.? It gives a combination of Screws and Rack. It's very efficient at around 80% with low backlash and if done correctly can give very close to the ball-screw performance. It still requires gearing to give you the correct feeds etc but with much less hassle than R&P gives regards setup and adjustment.


This is the first comment I remember seeing about the potential relative performance of belt drives, they don't seem very popular but have a lot going for them. Have you seen the Everman variation aimed at reducing belt stretch? This link is to the US patent for the design.
https://patents.google.com/patent/US20090301237

[JAZZCNC]

This is the first comment I remember seeing about the potential relative performance of belt drives, they don't seem very popular but have a lot going for them. Have you seen the Everman variation aimed at reducing belt stretch? This link is to the US patent for the design.
https://patents.google.com/patent/US20090301237

I was involved in the thread on CNCZone with Mike Everman who designed this system long before the patent went in and I've built 2 machines using this setup, and 6 machines in total using a belt drive. However, I moved away from it because ball-screws came down so much in price it wasn't worth the trouble for small to medium machines I mostly build. While belts are a good choice for larger machines they do put restraints on the machine regards the best place to locate them to avoid debris, then you have wear and maintenance to consider. Ball-screws are much simpler and far less maintenance.

[SweetAs]

Ok so first off, thank you for the replies.

Looks like I've got a huge amount to figure out and get planned in. Im more of a figure it out on the fly than a planner kind of guy but I understand the need for it in this situation so I'll get my head down.

In terms of size, what sort of frame footprint should I be looking at to begin with and will I be ok with the 80 x 80 x 5mm steel box section, can I go smaller or do I need to go bigger?

In terms of creating more mass to remove or dampen vibrations, is this why some machines will have additional weight added to the machine?

I don't have an issue with sourcing from China. The previous small builds I have done have all been China sourced and we have imported machinery before so we understand the process.

Forgive the confusion with the 100mm blanks, imagine doing a 2.5D carving or a mountain. That's close to what I'm thinking of, apologies I can't give out more of an idea. Sort of like a thick relief carving.

You right in the sense that I have little experience of big machines like this. My engineering side is fairly on point for what I understand but more than happy to take on board the comments 're the belt drive. What sort of size belt would I be looking at, they must be wide! Are you thinking of the usual single belt or would it be doubled up, is that even worth it? Do the issues with belt stretch still apply? Would it be better to look at an ally extrusion gantry to keep weight down if I'm looking at belt drive? Will belts not chase additional issues in terms of machine rigidity or am I over thinking it with the applications that I'm looking at?

Thanks again for taking the time to reply, I'm super excited about giving it ago but at the same time trying to keep the focused at what appears a mountain to climb lol.

Apologies for any spelling mistakes, I'm writing this out on my phone so autocorrect loves to kick in.

[JAZZCNC]

Im more of a figure it out on the fly than a planner kind of guy but I understand the need for it in this situation so I'll get my head down.

Resist the temptation because it will cost you money and frustrate. Key to a good machine built within budget is planning along with careful research and asking lots of questions.


In terms of size, what sort of frame footprint should I be looking at to begin with and will I be ok with the 80 x 80 x 5mm steel box section, can I go smaller or do I need to go bigger? .

I cannot answer to what size machine you need only you can know that.! What I can offer is that if your chasing space then consider looking at a vertical machine. it offers a big space saving along with other advantages. See video

80x80x5 will work but wouldn't go less for 8x4 or 10x5. I use 100x100x6.


In terms of creating more mass to remove or dampen vibrations, is this why some machines will have additional weight added to the machine?

It's not so much weight more density that's required. Adding extra weight just costs money because takes more power to move it around. The goal is to reduce vibrations but doing that by making things stiffer and adding weight can actually introduce vibrations because becomes more resonant. Materials that absorb vibrations are more beneficial which is why cast iron is often used in machines.



What sort of size belt would I be looking at, they must be wide! Are you thinking of the usual single belt or would it be doubled up, is that even worth it? Do the issues with belt stretch still apply?

25-30mm will work. If you want the best system then follow the Everman type setup as it keeps belt stretch to a minimum. That said if you use the correct belts then it's not an issue.



Would it be better to look at an ally extrusion gantry to keep weight down if I'm looking at belt drive? Will belts not chase additional issues in terms of machine rigidity or am I overthinking it with the applications that I'm looking at?

Better than what.? Regards ally extrusion then that's what I mostly use on all my router machines for the gantry. It offers several advantages over steel when comes to fastening rails etc and is very good at reducing vibrations. It's also much easier to work with if you haven't got a mill or machines to help.


https://youtu.be/wJB_75bLEIM

[routerdriver]

Not with the right spindle and design of the gantry / Z-axis. All the machines I build at this size will cut 100mm depth and retract the tool above the workpiece. However, The cutters are expensive and not easy to find. Work holding also becomes a fun challenge.!

That is an unusual amount of Z axis travel and really useful when you find a taller job that needs doing.I have had to work on 70mm thick jobs on a machine with 85mm of Z travel and it was quite,er absorbing.The comment about work holding is actually something that needs to be brought into this discussion; T slots in the table,threaded inserts or a vacuum system could all come into play.

[Boyan Silyavski]

For signage i will not go with a smaller than 8x4 machine if you are planning you to fabricate the stuff.
And when i say 8x4, better check the exact size of materials your providers will supply. for example in Spain all is 122x244cm, so my machine working area is 130 x 260 and i can cut the full length of the sheets

If you are working alone don't go with a bigger machine. And don't go with a vertical machine. In fact i greatly advice you against the vertical machine if you will be into the odd jobs like what i do. Explain to me how 1 person will load 100kg door onto it for a machining the door panel channels. And what about 200 doors? a job that will pay you off the entire machine at once. Also if you are one or 2 people, make the machine lower, like on the floor, you will thank me later.

If you are going to be seriously dedicated sign shop that even provides other sign shops in the area 300x150 cm is a must, as Dibond panels for large signs are that size. And best will be 400x200 and so you will take all jobs in the area , but this machine is for a shop with no less than 5 workers.


For this kind of work you better go with biggest spindle you can buy. As you will need to use insert tooling. I have on mine 3.2kw but only a couple of tools, i wish the collet size was not only 1/2 but 16mm or better 1 inch

Vacuum pump is a must for signage but you could do without it as i do, screws in bed at clever places. Serious vacuum pumps and the bed are a couple of thousand, i still can not justify that, as one man shop usually takes the odd jobs so not always needed.

A typical insert tool is 65mm long from the spindle then the bed, the work holding, etc. Nowadays i will not go with a machine with Z travel less than 180mm. Mine has 200mm and there were a couple of times i with it had 300, i had to split jobs..

For 3d jobs in PU or MDF or whatever epoxy the Z travel is very important, so is the fact that th spindle it self could become obstruction, so the spindle has to me able to slide down and the plate to clear the job.

Basically what i am saying a proper sign making machine is out of the scope of the usual DIY maker. Yes i did it and many others, but you will have to be very dedicated to finish it. Not to speak of that a proper one will cost you 8-10k in materials.

But when jobs start coming, you will reap the benefits.

And again- don't go with a vertical machine. If you have not place, you will need a lot more for the sign business

[routerdriver]

There is a lot of good advice in the previous post.There is also one piece I would disagree with,namely going to floor level with the machine.You will probably spend more time cutting sheet material than 3D machining and inevitably there will be a lot of tool changing and sheet positioning.You will get much less back ache and your knees will suffer less if the machine is set to a normal bench height.When you have a large or heavy item to place on the machine,it is a gret deal easier with one of these:

https://dccf75d8gej24.cloudfront.net/images/products/02/020110152/8CA991BB-4205-423F-914F-C4DBC3F27DC7-large.jpg


Not hugely expensive and also helpful when you need to lift the finished item into a van for delivery.The topic of machining tall workpieces is something to consider very carefully and I noticed the reference to the spindle itself being an obstruction,please consider this very carefully as a good number of novices seem to believe that building a machine with a large Z range means they will be able to machine anything that fits beneath the gantry.Not only does the body of the spindle represent an intrusion,the backplate on which it is mounted is also likely to have corners that could dig into the job.For taller and more complex work the 5 axis machine is the only way to go but obviously the complication and expense will increase by a lot.So too will the difficulty of finding a 5 axis CAM system with a good post processor.

[Boyan Silyavski]

I went with low machine as from the beginning i knew that definitely will work alone and also my lack of space. But i see how this lift table could help. You will not believe how much time i spend on top of table. Especially that i have found that if i hold by hand the finish pass on cut out letters that saves me hours of work later. basically i leave tabs and when all is ready i do one last pass where i hold each piece. Not with my fingers, i use pencils and the rubber side to push. I mean i am not sorry for the machine being low, it has other benefits also as being able to see easily what's happening even at the further end.

MIne machine was made Do It ALL but i had in mind especially 3d and the Z was specially designed so that the clearance is optimal, plate is only 1cm from spindle body, spindle slides down. But even so i have had difficulties with the clearance. And i absolutely agree if machine is mainly for 3d it has to be 5 axis and say Z 50 cm or more.
To machine a 80mm material i need a 100mm tool sometimes and that eats all the Z travel.


My biggest regret is i did not make the bed separated entirely from the frame. If i make a new one, i will make both sides and gantry separate from table and Z axis of say 50 cm travel. Well, its not a regret as when i was doing it i did not know exactly 100% what i want, maybe 90 percent. Now i know. What i said above and 5 axis:loyal:

[JAZZCNC]

If you are working alone don't go with a bigger machine. And don't go with a vertical machine. In fact i greatly advice you against the vertical machine

Boyan, you cannot advise about Vertical machine until you have used one and I doubt you've ever even seen on in real life let alone used one, so please don't make comments like this until you know what your talking about.!


if you will be into the odd jobs like what i do. Explain to me how 1 person will load 100kg door onto it for a machining the door panel channels. And what about 200 doors?


And again- don't go with a vertical machine. If you have not place, you will need a lot more for the sign business

Again you don't know what your talking about because never used one.!
All the Vertical machines I've built are for Sign people or coachbuilders and all of them are blown away by it being vertical. ALL of them cannot believe the difference it's made to there workflow, ease of use and amount of space it's saves them along with other benefits like tool life and quality of finish and no more back aching from bending over.!
In fact, I'm actually building a second 10 x 5 for customer where both machines will be located in a space where 1 horizontal machine would struggle to fit and be usuable.
Another signage customer as an 8x4 in a space that he struggled to fit 1000x1000 machine and again is blown away by it. He wouldn't trade you for horizontal if you gave him it for free it's made that much difference to his business.

Loading is actually very easy and in fact, for sheet work like signage, it's much easier than being horizontal. The weight isn't an issue because anything that weighs 200Kg requires either two people or lifting devices to be safe. In which case you select devices that suit your needs best. I regularly load 100Kg + sheets of Aluminium onto my bed alone.

Your comment regards doors is ridiculous because 1 door 2 or 3 doesn't make any difference, they are loaded just like any other material.
Regards working on parts on the bed and ease of access then it's much much better because you are stood up working at sensible heights with no bending over or back Ache. In fact, this one benefit alone to some people like me who suffer badly from backache is worth the decision to go vertical.

So please don't comment until you have experienced a vertical machine.!

[ericks]

Interesting thread, i will be keeping an eye on this...
Personally i do not like the idea of a vertical machine :)

[Boyan Silyavski]

So please don't comment until you have experienced a vertical machine.!

It's a forum and i will comment as much as i feel the need to. It's my opinion, grownups could decide for themselves. I am a final user and use my machine daily for various jobs, from high volume production to making the odd sign, from aluminum, all plastics to foam. So lets say i know a bit about what i am talking. I know about the vertical machine of yours from a long time but i have never felt the need of one. There is one main reason i did not mention- dealing with dust. Dust from wood and dust from foam and plastics. Many times on an odd job dust shoe could not be used. You know i make custom dust shoes so if i say so, its so, not that i don't have a proper extraction. Then only gravity keeps foam or plastic dust from flying around. In fact that's what one of the main reasons to make my machine with raised sides and low bed.

What you are saying to me is like i say to you : Please don't comment, you sell machines you know nothing of what the final user really needs. I will not say that, lo lets keep civil here.


You may know a lot but what, other people can not say their opinions? Its same on the thread about the controllers. I am just suggesting other options. Not 2 people use the machines they have in the same way, so more options, the better.

[JAZZCNC]

It's a forum and i will comment as much as i feel the need to. It's my opinion, grownups could decide for themselves. I am a final user and use my machine daily for various jobs, from high volume production to making the odd sign, from aluminum, all plastics to foam. So lets say i know a bit about what i am talking.

I never said don't comment, I said Don't comment on what you do not know about. You have never used a Vertical machine or even seen a vertical machine in use so how can you advise someone not to go that route.?

Maybe it's a language barrier thing but like the Controller thread you mention, your comments are worded such that it comes across as your way is the only way and only your way is the correct way.!. .Well it's not my friend and this needs to be pointed out.

In that thread, my comments were to let others know that a PC works just fine I never advised on any best way or controller. I gave my opinion on what I used and way, also why I personally didn't like the DDSV after trying it.

I didn't tell anyone not to use it and I certainly didn't advise anyone not to use or buy a controller that I've had no previous personal experience off or in fact even know anyone who has like you did with your comment on the vertical machine advise.
You'll never find me commenting or advising anyone to build or buy something I've not built or tried my self and suggest you and others do the same. Because while you think your helping your actually not if you have had no previous experience of the product, what you are actually doing is potentially swaying people in a direction that may not be the best for them.
By all means comment and give your opinion but please shut the f'#k up when it comes to telling them NOT to take a route you have never been down.!

[JAZZCNC]

Interesting thread, i will be keeping an eye on this...
Personally i do not like the idea of a vertical machine :)

Ye but that's like me saying I don't like the idea of holiday Oz because it's a long flight and got sharks in sea.! . . . Where the reality is I pretty much guarantee if I took that flight I'd love it when got there and go swimming everyday.! . . . But untill I try it I'll never know.?

And no where would you see me say DONT go to OZ because it's a on opposite side of world and you falloff because your upside down.!!

[Voicecoil]

The vertical machine idea is interesting, and I don't see that loading would be any more difficult - if I was working solo I'd just add some rollers on the lower side of the bed to ease feed-in, and maybe make a wee trolley kind of thing so I could roll sheets around on their edge at the right height. One thing it likely would need is some serious vacuum though to get good hold down as gravity won't be helping much. BTW Jazz, is the X (long) axis drive standard ballscrew on the machine in the video? - couldn't really see easily.

[AndyUK]

Ye but that's like me saying I don't like the idea of holiday Oz because it's a long flight and got sharks in sea.! . . . Where the reality is I pretty much guarantee if I took that flight I'd love it when got there and go swimming everyday.! . . . But untill I try it I'll never know.?

Totally off topic, but you should definitely go down under. Once it's stopped burning, that is. But do NZ first. No one can dislike NZ, it's like a playground paradise with nice people, food, scenery... God damnit I want to go back to living in NZ.

[JAZZCNC]

One thing it likely would need is some serious vacuum though to get good hold down as gravity won't be helping much. BTW Jazz, is the X (long) axis drive standard ballscrew on the machine in the video? - couldn't really see easily.

The machine in the video didn't have Vacuum because budget wouldn't allow for it and the customer is happy screwing/clamping material down. It's mostly cutting signage materials.

Yes it's using standard 25mm ballscrews with BK bearings.

I'm currently building a 10 x 5 with ATC and vacuum bed that uses Rotating ballnuts which I'll post a video of when done.

[JAZZCNC]

Totally off topic, but you should definitely go down under. Once it's stopped burning, that is. But do NZ first. No one can dislike NZ, it's like a playground paradise with nice people, food, scenery... God damnit I want to go back to living in NZ.

I've actually got a friend who lives NZ, he married a native girl. He keeps saying to go over for Snow boarding hol so it's on the to-do list.