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woodspiral
27-12-2013, 05:38 PM
Hi CNCers,

I'm looking around for some detailed plans to build a CNC machine. I've got good wood, metalworking, electronics and computer skills but this will be my first machine so the more detail the better. I don't mind paying for plans but anything over 30 I'm going to have to think carefully about it. These plans look good:

24x48~Solsylva CNC Plans (http://solsylva.com/cnc/rack_pinion.shtml)

Can anyone vouch for these or suggest alternatives please? Plans specific for UK parts would be preferred.

The primary application is cutting wooden parts for furniture, so the cutting envelope would have to be on the large-ish side - perhaps 2m x 1m x 0.2 m.

Many thanks,
Woodspiral.

EddyCurrent
27-12-2013, 08:05 PM
woodspiral, I started with a similar outlook, first I just wanted to buy a machine because I was more interested in using it than building it. After reviewing loads of commercial offerings I found them to be either too expensive or they lacked features I required, this ultimately led me to building a machine to my specification. Most plans I think are American and they seem to have different build techniques than we do in the UK, but that is not say one method is wrong. My suggestion is that you look through the build logs here, I know it gets to be a ball ache after a while, then cobble together the bits you like into your own design. The main reason is that you will learn far more by doing this and it will pay dividends later on I believe. All you need do is download the free Sketchup software and get going, once you overcome the initial hurdle of actually making a start it will come together quite quickly.
It would be different if you were looking to buy a kit of parts but as it's only the plans you seek I'm inclined to think you could produce these just as well yourself.

JAZZCNC
27-12-2013, 10:58 PM
Agree 100% with Eddy thou I'm going to suggest you keep the size down to the minimum length you need because it gets quite a bit more involved building a good machine has the length increases and 2mtr+ machine I wouldn't recommend for a first time builder unless you either study in detail what's required for both design and components or seek advice from someone who's actually built a working machine at this length.!

Like Eddy suggests I wouldn't waste time or money on plans has everything you need is here on the forum and most plans I've ever seen have been crap and designed to be made from wood which is a recipe for disaster and disappointment.

Read some Threads then read again until you understand the pitfalls, post a build thread with what you have in mind and ask for advise on anything you don't understand.
Don't Rush in with building or buying components until your 100% sure they are the correct for your needs.

MikeyC38
28-12-2013, 02:10 AM
Hi woodspiral
I too started with the Solsylvania plans but when I started to price it up for decent wood, aluminium excursions was cheaper and stronger! I completely agree with the previous posters and suggest you follow their advice. These guys have helped me greatly with the advice and help which has saved me from costly errors. I am now building a aluminium router and will post my build log shortly. I has taken me 2.5 years to get to this stage and there is still more to learn!
Regards Mike

Boyan Silyavski
29-12-2013, 01:36 AM
Instead of buying plans, just make a plan:
-read the build logs
-learn Sketchup/free/ to draw your machine/ very simple to learn and extremely fast to draw using 5-6 buttons and mouse/
-make a build thread

One thing to say. Ok , i have to say it because its true- This is the best forum in internet for CNC. The knowledgeable and friendly people make it so. But mostly, you will see here far better designs than the typical "plans for sale", even than most of the commercial routers.

woodspiral
29-12-2013, 04:33 PM
Thanks very much for the replies. It's not really what I want to hear! This is for a professional application so I need to make a full-sized machine (2m x 1m x 0.2m approx) and I don't have time to make a smaller prototype. If I had tons of cash I'd buy a top end 5-axis machine, but my budget pretty limited, so it looks like a 3-axis self-build for me.

My problem isn't really the design as such it's the choice of parts. I can use SketchUp and AutoCAD but that's not the problem. For example, given my desired machine size, one fundamental problem is to make two runners 2m long and 1m apart. These have to be absolutely level and parallel to each other. I need to know what type of materials are ideal for that and what kind of equipment and processes are used to install and measure them. That's obviously just the start. I read the CNC cookbook so I do have an idea of the various components.

I'm thinking that perhaps instead of 'plans' I should have said 'plans/kit'. I looked briefly at this site here:

www.cncrouterparts.com

And judging from their specs and few blogs from people who've assembled their kits, it looks good (any views?)
One issue is that they are US-based, but they would ship to the UK for a cost. Perhaps there is a company in the UK like that?

In summary: not a huge amount of free time, limited budget, large-ish machine for commercial use.

Thanks,
Woodspiral.

EddyCurrent
29-12-2013, 05:19 PM
It's sounding like ebay is going to be your friend, a second hand ready built may be the best bet here.

JAZZCNC
29-12-2013, 07:20 PM
Thanks very much for the replies. It's not really what I want to hear! This is for a professional application so I need to make a full-sized machine (2m x 1m x 0.2m approx) and I don't have time to make a smaller prototype. If I had tons of cash I'd buy a top end 5-axis machine, but my budget pretty limited, so it looks like a 3-axis self-build for me.

Maybe not want you want to hear but it's all good straight advice that's been learnt the hard way by me and others. I'm often contacted by silent watchers who have jumped straight in and not done the prep or homework only to fall foul buying wrong parts or choosing a weak trouble some design. . . . . If you continue and don't put in the ground work then I guarantee you you'll fall foul and be contacting some one within time.!!


My problem isn't really the design as such it's the choice of parts. I can use SketchUp and AutoCAD but that's not the problem. For example, given my desired machine size, one fundamental problem is to make two runners 2m long and 1m apart. These have to be absolutely level and parallel to each other. I need to know what type of materials are ideal for that and what kind of equipment and processes are used to install and measure them. That's obviously just the start. I read the CNC cookbook so I do have an idea of the various components.

Doesn't matter if you buy a Kit or build DIY your going to have to deal with getting the Rails parallel and on the same Plane. If your not prepared to do this then I suggest you just buy a Machine ready built because there are no kits that will bolt together(or weld) and ensure the rails are parallel and on same Plane.

Aligning and getting rails aligned etc isn't difficult has it first appears and there are a few tricks which can be employed like having an adjustable top rail which gets shimmed or using epoxy resin. Because your only cutting wood then the tolerances are relatively low so it's quite easy and quick to get rails close enough just using shims.


I'm thinking that perhaps instead of 'plans' I should have said 'plans/kit'. I looked briefly at this site here:

[COLOR=#555555][FONT=arial]www.cncrouterparts.com

And judging from their specs and few blogs from people who've assembled their kits, it looks good (any views?)
One issue is that they are US-based, but they would ship to the UK for a cost.

Now regards the CNC router parts machine then yes they work but they have there issues which don't get mentioned so much, like the rails clogging bearings and sticking Etc.!! . . . I certainly wouldn't call it commercial spec and not even Heavy duty DIY.! . . . . A much better machine with far more robust components can be built for less money.

Regards Components then be careful when reading sites like Cnc cookbook because they are quite heavily Mill orientated and while routers use the same Kind of components the sizes and speeds they run at are much higher so are very different specs. Then you have other things to consider like best Linear motion for the Job, IE Ballscrews or Rack & pinion which again are very different spec to mills and critical to good performing machines.

It's actually here where new users most commonly fall foul and buy the wrong parts for the job which leads to at best an under performing machine or worst one not fit for purpose. Next is weak design and trying to cut corners.!!

So IMO given your Brief of Commercial duty and Low Budget then your only option is to self build but PLEASE PLEASE LISTEN and do the home work on the forum because if not then you'll waste valuable time and Money.!

Good luck.

woodspiral
01-01-2014, 03:56 PM
If you continue and don't put in the ground work then I guarantee you you'll fall foul and be contacting some one within time.!!

I was hoping that a set of instructions would exist for download or purchase that would describe in detail all the groundwork and pitfalls of the process.



Doesn't matter if you buy a Kit or build DIY your going to have to deal with getting the Rails parallel and on the same Plane. If your not prepared to do this then I suggest you just buy a Machine ready built because there are no kits that will bolt together(or weld) and ensure the rails are parallel and on same Plane.

I am prepared to build the machine, because I think I can end up with a better quality machine which I will fully understand and be able to maintain. I don't want to go the Ebay/secondhand route for a fully built machine as it will increase the cost for me and also will not learn as much in the process. I'm happy to spend time researching, designing and constructing, but since my time is rather limited I want to spend this time on a machine that is ready for light commercial use, with the cutting envelope size as described above. I don't really have time to make a small prototype. At the other end of the scale, I'm not so much in a desperate hurry that I need to rush out and buy a machine.


Aligning and getting rails aligned etc isn't difficult has it first appears and there are a few tricks which can be employed like having an adjustable top rail which gets shimmed or using epoxy resin. Because your only cutting wood then the tolerances are relatively low so it's quite easy and quick to get rails close enough just using shims.

Yes I watched a YouTube video about this, it seems fairly straightforward given time and some modest equipment.


Now regards the CNC router parts machine then yes they work but they have there issues which don't get mentioned so much, like the rails clogging bearings and sticking Etc.!! . . . I certainly wouldn't call it commercial spec and not even Heavy duty DIY.! . . . . A much better machine with far more robust components can be built for less money.

This is an extremely interesting observation. Firstly about quality and secondly about the cost. Again, I am motivated for getting the best from the investment and time and money. So given all the advice so far (if you guys are to be believed!) then it seems to make sense to start a build thread here, start researching and start designing. I can post my progress and invite people to give me some feedback.


Regards Components then be careful when reading sites like Cnc cookbook because they are quite heavily Mill orientated and while routers use the same Kind of components the sizes and speeds they run at are much higher so are very different specs. Then you have other things to consider like best Linear motion for the Job, IE Ballscrews or Rack & pinion which again are very different spec to mills and critical to good performing machines.

I meant the CNC Cookbook book by Edward Hess, not a website. The cnccookbook website seems to be maintained by a guy called Bob Warfield and therefore not related to the book.


It's actually here where new users most commonly fall foul and buy the wrong parts for the job which leads to at best an under performing machine or worst one not fit for purpose. Next is weak design and trying to cut corners.!!

I'll most likely design and build this in stages, so I can get feedback about choices before it's too late to correct.


So IMO given your Brief of Commercial duty and Low Budget then your only option is to self build but PLEASE PLEASE LISTEN and do the home work on the forum because if not then you'll waste valuable time and Money.! Good luck.

Noted! Thanks very much!
Woodspiral.

JAZZCNC
01-01-2014, 04:30 PM
I meant the CNC Cookbook book by Edward Hess, not a website. The cnccookbook website seems to be maintained by a guy called Bob Warfield and therefore not related to the book.

Ok yes I know the book. Not read it so can't comment but still stand by my advice to be careful and fully check out what you think is needed is actually what's needed for the size and style of machine your planning on building.!

My concern with these books is that often the authors are just that "authors" and much is taken from research in industry, some times dated research and presuming perfect building conditions with little to NO hands on experience with DIY CNC.
DIY Cnc is very different, very easy to get wrong or under estimate what's needed(Some also Actually over do it for there needs which is better but wasteful) which has to be built in very much less than perfect conditions so Advice from people who have actually built machines is price less IMO.

Now here's another Warning regards Forums, (which if your used to forums and I'm teaching Dad to suck eggs then I apologise) and why your much better looking around the build logs to spot the tyre kicking "KNow-it-Alls" who have never actually built a machine but dish advise like expert builders can be just has misleading has a Dated unrealistic Book.!

Edit: Ah ah forgot to say thankfully this forum doesn't have many of those types around other Than Jonathan and John S and Me. . :thumsup:

Crack on and get reading.!!

johnsattuk
01-01-2014, 10:08 PM
Edit: Ah ah forgot to say thankfully this forum doesn't have many of those types around other Than Jonathan and John S and Me. . :thumsup:


Classic get out clause :thumsup:

JAZZCNC
01-01-2014, 10:36 PM
Classic get out clause :thumsup:

Nah it's the truth mostly but ye I knew I'd take shit if I didn't say it.!!

JAZZCNC
01-01-2014, 10:50 PM
Yes I watched a YouTube video about this, it seems fairly straightforward given time and some modest equipment.

I'm sure some on here would like to see that Video could you post a Link.
I've never seen one before on youtube and have been waiting until next time I do one so could make a video to show others how it's done.

mekanik
02-01-2014, 11:19 AM
Woodspiral
I am a noobe so know nowt but did find this an interesting read and it's about the size you are looking for
Machine frame - MadVac CNC (http://www.oneoceankayaks.com/madvac/machine_frame.htm)

JAZZCNC
02-01-2014, 12:01 PM
Woodspiral
I am a noobe so know nowt but did find this an interesting read and it's about the size you are looking for
Machine frame - MadVac CNC (http://www.oneoceankayaks.com/madvac/machine_frame.htm)

The epoxy method he uses is pretty much the same way I do it but I use Mixture of epoxy putty's and Epoxy resin's and don't really bother with the fillers has I've found they are not needed unless having a thick layer.
For bolted frames then the process is timely and the Dowel pins take some time and effort, but if welded steel frame and you use an adjustable top rail then it's quite easy really. Just careful setup and epoxy putty. Beauty of epoxy putty is you have plenty of time to do this and it's not messy, can also be sanded, shaped, drilled & tapped just like metal when dry so it's good for filling gaps and holes. If in use you find you just quite didn't get the rails 100% on same plane or parallel then it's very easy to shim into plane with fine shims. (Tin foil works a treat)

Damning the top rails with a bridge and flooding with epoxy also works well but takes more time and effort can also be messy, so it's important to have good seals other wise leaks will happen and then shrinkage in places. It's also not so easy to fine tune if you haven't quite it the mark.!!

Neale
03-01-2014, 11:21 PM
I have no personal experience of building and using a metal-frame CNC router. However, I do have a "working" MDF machine in my garage, built to a slightly modified version of the open-source JGRO design (Google will give you plenty of references). I have indeed used it to cut some useful items. After 6 months or so, I have decided that I need to replace it with a decent metal-framed machine. Does that tell you something?



I've learnt a lot:
- I have a box of electronics that works well and is sized for a bigger and more powerful machine, complete with steppers also reusable.
- I've had a lot of practice with CAD and toolpath-generation software. Free does not necessarily equal best...
- A 2KW water-cooled spindle provides much more cutting power than the machine structure could possibly cope with. And its weight is more than MDF can cope with, as well. See below.
- A home-made anti-backlash delrin nut assembly works fine. I can't say the same about M10 stainless rod used as a leadscrew. Not sure what the theoretical critical speed is, but in practice it works out at about 800mm/min for the X axis.
- A "rapid" feed that is slower than most people's cutting speed isn't too important when the max cutting speed is (depending on cutter, etc) around 200-300mm/min. At this point, I hear the experts laughing, holding their sides, and saying, "I told you so..."
- You can get an enormous amount of satisfaction out of building something that works. I've cut a presentation plaque in hardwood, engraved some Christmas presents very acceptably, and even sold a few small items. I just had to do it very, very slowly, and with a lot of shimming of spoil boards to get something to approximate a level bed. I even improved the original design by replacing some MDF components with pieces made on my 3D printer (also home-built) but this just shows up deficiencies elsewhere.
- MDF is not the most stable constructional material. Actually, it's not stable at all. Or even suitable as a constructional material. OK, I should have varnished or painted it, but I doubt that it would have made much difference. Just before Christmas the bed had a sag in the middle of around 3mm in 300mm, and with the recent high humidity it's probably worse than that and still going. My son has built a very similar machine and stiffened the bed with a couple of lengths of 1" square steel tube which has helped, but the Z axis plate is now a few degrees off vertical due to MDF sagging under the weight of the spindle.

There are people who have built a JGRO design more or less as per the plans and used it for some fairly serious work. Well, not in my local micro-climate! On the other hand, if I reuse all the steppers, control electronics, spindle motor and VFD, etc, I shall be throwing away less than 100 of materials, mainly MDF and steel pipes used as linear bearings. Even the skate bearings for the three axes altogether probably cost less than a tenner off Ebay. I always had the thought in mind that this would teach me what I, personally, could do with a machine like this and that the first machine would have to be considered disposable.

I am currently putting together an outline design for a slightly larger machine, to be steel framed with decent bearing rails and ballscrews, and this will be presented to the community for comment. In particular, I have some idea of what is possible with a somewhat crude and flexible machine, and I don't want to go the other way and grossly over-build. But if you want a sensible size machine, don't think about wood. Ply might be better than MDF, but for a machine for commercial purposes in any size? Don't go there!

woodspiral
08-02-2014, 11:44 PM
Hi,

Thanks again for all the ideas and suggestions. I have done *some* reading through the build logs but by no means complete. I have begun writing lists of specs in categories. I've posted them here for any early comments people would like to make:

http://www.mycncuk.com/forums/gantry-router-build-logs/7146-build-log-doris-cnc-early-feedback-appreciated.html#post54830