Am I being silly?

Hi, I have been lurking here for quite a while and am now thinking of taking the plunge (!) and building some form of cnc router. Before I dive in (and probably get it all wrong) I would welcome comments on what I am thinking of doing.

First though, some background.....
I have 3 3d printers, one of which I built myself from scratch so think I understand the principles of CNC. I also have a dilapidated single garage as a workshop which is so full of stuff I can hardly move around but there is a lathe, pillar drill, belt sander and a fair selection of hand tools in there. Space though is a problem!
I also have too many things to do at the moment so, if it is to have any chance of success, I need to keep any build as simple as possible!

To that end I set a basic spec for a machine:
- 800x500x500 machine dimensions with the biggest practical work area. Anything over 200 x 300 workable area would be acceptable though.
- workpieces likely to be more 2.5d rather than 3d, so a small (maybe 100mm?) Z is probably ok. I suspect allowing for tooling and workholding will impact the z height more than the workpiece itself.
- capable of cutting aluminium and brass. Steel would be a bonus but I have no illusions that that will be sketchy at best with what I am likely to make.
- cheap! Target cost is around £500 although I am fully aware it is likely to go massively over budget by the time I have made it do what I really want.

Also, I might upset a few people here with this but, based on my experience with 3d printers, I would rather start cheap and "just about ok" knowing I am likely to upgrade later than go straight in with an over-engineered solution that will do anything. I know this sounds strange but I somehow enjoy the challenge of making things work and finding out what are really the critical things that need to be done right. As an example, I started out with an Anet A8 3d printer. It was only by getting that working as best it could (and having bought an ender3 and also fixed that) I reckoned I knew how to make my own design. I still have the A8 though and it still prints as well as anything else (if a bit slowly).

Anyway, to the point.....

Given the small size and need to keep it simple and rigid I am thinking of going with a fixed gantry design. Sensible?

For rails I am thinking of going with SBR supported rods. Two reasons: 1) cost. 2) tolerance to mounting errors. My custom 3d printer was made using 2040 extrusion with linear rails and I was surprised how difficult it was to make the mounting surfaces coplanar. Even slightly distorted extrusion meant I had to mill then flat to stop binding.
Given how I am thinking of making the frame (next point) that puts me off linear rails and I certainly don't think unsupported rods will work. Will I regret not going with rails even on this first build?

Lastly, frame material. Again, this might be controversial - I am thinking of using plywood! My reasoning being that I initially want something quick and easy to build that is rigid enough to start making parts for a mk2 version (there is bound to be one so I might as well plan for it...). Steel would need welding to make it worthwhile (I haven't used my welder in 10 years) and would likely resonate unless filled with epoxy granite or sand. It is also hard to modify and experiment with, as is aluminium (unless I had a working cnc router). Wood is good for stopping noise and resonances, can be stiff if built properly (especially given it is a fixed gantry design) and is cheap an easy to work with. The down side is that it is almost impossible to make things accurately and it likely to distort and move over time. I am thinking that is not really a problem for my first build though as it should be "good enough". This is for the main frame and gantry (and maybe) the moving bed. The z axis assembly is likely to be aluminium. Obviously it will be thick laminations and box sections to get the rigidity, not just flat ply sheets.

So, am I being silly? ;)

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Originally Posted by brman

So, am I being silly? ;)

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In a Nutshell Yes.!

There is no way you can build a machine that can cut aluminum and brass to any reasonable degree from wood and with only a £500 budget.

I said this to someone else recently also. The plywood alone will cost you more than steel, The only place for MDF in CNC for lighting fires to keep shop warm and using as a spoil board. Don't do it.!

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Originally Posted by JAZZCNC

In a Nutshell Yes.!

There is no way you can build a machine that can cut aluminum and brass to any reasonable degree from wood and with only a £500 budget.

I said this to someone else recently also. The plywood alone will cost you more than steel, The only place for MDF in CNC for lighting fires to keep shop warm and using as a spoil board. Don't do it.!

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Well, to be fair, I did sort of expect that response ;)

Just to clarify though, I would not use MDF (other than for a spoil board). It is nowhere near rigid and stable enough. Plywood I thought might be if constructed properly but it sounds like you are telling me otherwise.
Anyway, leaving that aside, any comments on the use of supported rods vs linear rails and fixed vs moving gantry? Am I more on track with those decisions?

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Originally Posted by brman

Well, to be fair, I did sort of expect that response ;)

Just to clarify though, I would not use MDF (other than for a spoil board). It is nowhere near rigid and stable enough. Plywood I thought might be if constructed properly but it sounds like you are telling me otherwise.
Anyway, leaving that aside, any comments on the use of supported rods vs linear rails and fixed vs moving gantry? Am I more on track with those decisions?

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My advice is to price up the steel from a good steel supplier because I think you'll get a shock. To make a machine that is anywhere near strong enough and good enough will require a lot of high-grade plywood which isn't cheap.

Regards the linear rail question then I'd go with profiled linear rails every time over round type. That said I'm not advising you not to use them and in fact, if you do go down the plywood route then I'd advise you did because it will be easier like you said and the accuracy and strength profiled offers would just be wasted anyways.

The best advice I can give you is to forget any idea of building it then upgrade as you go along. The upgrade route never works as usually what you find or would like to upgrade to requires a whole need or different machine anyways.
If it's just to learn on then could say fine build it cheap.! But in reality, it's no more difficult to build it correctly the first time or in such a way that it's very close and not too difficult to improve if needed. Plus if it turns out that you need a completely different type or size of machine you'll get your full money back and if done correctly may even make a profit which you can put to the next machine.
With a plywood machine it will be worth nothing but firewood when finished with, components like round rails won't be good enough for the next build or correct size even, so very little of the machine will be reusable. So all that time and investment will be wasted.

Don't do it is my strong advice. Take a little more time and research what you need, ask questions so you find the best components to suit your needs and be patient don't rush to buy components or build it too quickly. Like most things that are built from the ground up there is an order in which it's best to tackle the job. It's also like eating an Elephant.? One small bite at a time so no rushing.

Thanks, that is very useful and definitely gives me food for thought.

It does give me a problem though. From my experience with aluminium I don't think a basic extruded design is going to ideal either. Which is probably why you recommend steel?

My problem is that I am concerned how I would make a decent steel frame with the tools I have available and without excessive work. Specifically, steel sections are not generally dimensionally accurate so getting rails coplanar without milling or resin leveling. I am also concerned that if I weld then things will distort (I am very much an amateur welder!).
What I don't want to do it invest time in a steel frame which ultimately ends up looking like a pringle ;(
I realise this might sound contradictory when I was earlier talking about plywood but at least with plywood I can easily adjust with files, planes and sanding.

Maybe that should have been the question? How best to make a steel frame that is accurate enough?

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Originally Posted by brman

Maybe that should have been the question? How best to make a steel frame that is accurate enough?

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Tack weld opposite points. Progress slowly and methodically, setting up as accurately as you can and measuring as you go. All you need is a stick welder, a grinder, and a tape measure.

Then level with epoxy. It's completely doable, loads of people on here have written about their experiences and how to do it. If you screw it up (like I did my first time) chip it off and try again.

Alternatively, skip the hard stuff and use aluminium profile. You'll be bolting your rails on in minutes rather than days or weeks (or you know, in my case, months).

If you want to cut metal on the machine,just find an old mill and add ballscrews and steppers.It may go over budget but it will work.Cutting metal on a woodworking machine may,just,sort of,be possible.That doesn't mean its a really good idea and trying to do it on a machine with a lot of Z travel, with all the consequent magnified play in the system won't help.For a hobby machine that just cuts wood you can do some stuff with a wooden machine.There are some extremely lightweight machines all over youtube delighting their owners,even if they wouldn't be much use in an industrial environment.You just have to be realistic about balancing budget,usage and building ability.The answer is out there once you carefully consider which features matter most.

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Originally Posted by AndyUK

Tack weld opposite points. Progress slowly and methodically, setting up as accurately as you can and measuring as you go. All you need is a stick welder, a grinder, and a tape measure.

Then level with epoxy. It's completely doable, loads of people on here have written about their experiences and how to do it. If you screw it up (like I did my first time) chip it off and try again.

Alternatively, skip the hard stuff and use aluminium profile. You'll be bolting your rails on in minutes rather than days or weeks (or you know, in my case, months).

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Which I think highlights my problem. careful welding (with lots of practice first), epoxy levelling. It just isn't going to happen. I need to find a easier route or just not bother.

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Originally Posted by routerdriver

If you want to cut metal on the machine,just find an old mill and add ballscrews and steppers.It may go over budget but it will work.Cutting metal on a woodworking machine may,just,sort of,be possible.That doesn't mean its a really good idea and trying to do it on a machine with a lot of Z travel, with all the consequent magnified play in the system won't help.For a hobby machine that just cuts wood you can do some stuff with a wooden machine.There are some extremely lightweight machines all over youtube delighting their owners,even if they wouldn't be much use in an industrial environment.You just have to be realistic about balancing budget,usage and building ability.The answer is out there once you carefully consider which features matter most.

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Which is where I am at the moment, trying to balance time, budget and quality. I've seen pictures of high quality machines and, while I probably have the ability to make one, I don't have the time (or inclination). I have also seen MPCNC cutting ally acceptably (to me, not a production engineer) on youtube. So the question is really how low can I go without wasting my time?
I am tempting to try and see but I just know that will be followed by a lot of people saying I told you so...... ;)

I won't criticise anybody for doing their best to make something work.I started with an MDF machine and drawer runners,which gradually got changed to SBR12 rails.I also use a much derided breakout board off a parallel port running LinuxCNC and it has never let me down.The crux of the matter is that we have the freedom to build with materials we are comfortable with and running software of our choice.If it doesn't meet our hopes,then clearly we made at least one wrong choice-at which point we get to decide what we do about it.

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Originally Posted by brman

while I probably have the ability to make one, I don't have the time (or inclination).

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That one statement right there is why you should give up right now.!

If you don't have the budget to buy one and you don't the time or inclination to build one then just call it a day and save your money for when you do. If you proceed then it's highly likely you'll just blow money or as often the case when taken on half-hearted you'll fail and give it up.

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Originally Posted by brman

It just isn't going to happen. I need to find a easier route or just not bother.

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Then you need to be looking at purchasing a solution. Although even those will require you to put some effort in to diagnosing and troubleshooting problems along the way.

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Originally Posted by routerdriver

I won't criticise anybody for doing their best to make something work.I started with an MDF machine and drawer runners,which gradually got changed to SBR12 rails.I also use a much derided breakout board off a parallel port running LinuxCNC and it has never let me down.The crux of the matter is that we have the freedom to build with materials we are comfortable with and running software of our choice.If it doesn't meet our hopes,then clearly we made at least one wrong choice-at which point we get to decide what we do about it.

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Thanks, yes, I have read enough to know what are the "best" ways of do things but "best" is not necessary most suitable for me at the moment. In my mind it is a compromise between making enough wrong decisions to learn and not making so many I give up :rolleyes:

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Originally Posted by JAZZCNC

That one statement right there is why you should give up right now.!

If you don't have the budget to buy one and you don't the time or inclination to build one then just call it a day and save your money for when you do. If you proceed then it's highly likely you'll just blow money or as often the case when taken on half-hearted you'll fail and give it up.

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I can see why you said that but I think we have different priorities. I see nothing wrong with experimenting for experimentations sake, even if it is not the "best" or conventional way of doing it.
Plus, there is no such thing as failure in my view. If I did nothing that would be a failure as I would have learnt nothing. If I do something and it does not perform as I hoped then fine, there is no failure there as the success is in the learning.

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Originally Posted by AndyUK

Then you need to be looking at purchasing a solution. Although even those will require you to put some effort in to diagnosing and troubleshooting problems along the way.

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As above, I guess I should have made it clearer why I am doing this. It is not just to get a machine that makes parts I want. If that was the case I would just take my cad models to a cnc prototyping place and pay them. It would probably work out cheaper in the end! Lastly, time wise, I am not saying I don't have the time to tinker and fix things, just that I have to take that into account overall. ie. there is no point me spending all my available time making the best steel frame in the world but not having the time to sort the drives/control etc.

This might all sound like I am trying to justify to myself ignoring the good advice here. I am not, honest! I am still concerned about the effort of making a square and flat steel frame though, so I think I might need to consider ally extrusion again. Something for me to think about anyway. If I go that route then the choice between supported rod and profile rail is mainly one of cost vs performance.

Which I think leaves the other question. Fixed gantry, is that the right way to go for a small machine like this?

When i built my latest machine i used aluminium extrusion. However i had a reasonable budget so i used heavy duty extrusion. It's a moving gantry design but i have no problem with a fixed gantry type. Although my machine is made from extrusion it is very rigid, i machine aluminium very easily and also do steel plate on it. Although i prefer not machining steel cause of the mess it makes.

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Originally Posted by ericks

When i built my latest machine i used aluminium extrusion. However i had a reasonable budget so i used heavy duty extrusion. It's a moving gantry design but i have no problem with a fixed gantry type. Although my machine is made from extrusion it is very rigid, i machine aluminium very easily and also do steel plate on it. Although i prefer not machining steel cause of the mess it makes.

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Thanks ericks, do you have photos of the machine or a build diary?

Not latest cause i am constantly adding stuff, but this was taken a while back when i was busy adding a bit of guarding over the ball screws...I did do a few things on this build that i would change on the next one. My experience is more on panel building rather than machine building :)
I started by first building a steel stand.
Attachment 27076
Attachment 27075

Thanks, that does look like a very nice, solid machine.

Thanks, yes it's heavy and rigid. There was opportunity to make it even more rigid but i found it is good for what i need atm. There are so many options re machine designs. My next one will look much different to this one. All the best with your journey :)

Thanks, I am curious how you joined the extrusions. For my 3d printer I tapped the ends of of the exrusion and used bolts to clamp them together. I then braced the corners with plates underneath. Like this....
Attachment 27077
but I was never very happy with this. Ok for a 3d printer but pretty easy to pull the joint apart as it clamps only to the thin wall of the extrusion.

This is the best pic i have atm showing the connectors

Attachment 27078

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Originally Posted by brman

I can see why you said that but I think we have different priorities. I see nothing wrong with experimenting for experimentations sake, even if it is not the "best" or conventional way of doing it.
Plus, there is no such thing as failure in my view. If I did nothing that would be a failure as I would have learnt nothing. If I do something and it does not perform as I hoped then fine, there is no failure there as the success is in the learning.

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I try to help people avoid problems they cannot see by using all my experience of building machines and helping 100's no 1000's of people over 15yrs+ who have taken similar routes and nearly gave up due to either poor design and build frustrations or woeful under budgeting. You gave a Budget of £500 so all my advice was based on this. You also proposed design material that is neither cheap or suitable for a successful machine.!

I understand the experimenting for experimentation's sake I do it every week in some way or another. But what I don't understand is why to do it when you are being advised by an experienced builder that there are better ways which won't cost any more money and in fact, will probably cost less.? All it would take is to experiment with a Welder.?

I also don't understand why anyone would join a forum seeking advice then ignore it.? Also, don't get why someone would seek to build a machine but state they have no time or inclination to build one.? . . . This seems to me you just like wasting people's time so you'll get no more from me I'm afraid. Good luck.!!

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Originally Posted by JAZZCNC

I try to help people avoid problems they cannot see by using all my experience of building machines and helping 100's no 1000's of people over 15yrs+ who have taken similar routes and nearly gave up due to either poor design and build frustrations or woeful under budgeting. You gave a Budget of £500 so all my advice was based on this. You also proposed design material that is neither cheap or suitable for a successful machine.!

I understand the experimenting for experimentation's sake I do it every week in some way or another. But what I don't understand is why to do it when you are being advised by an experienced builder that there are better ways which won't cost any more money and in fact, will probably cost less.? All it would take is to experiment with a Welder.?

I also don't understand why anyone would join a forum seeking advice then ignore it.? Also, don't get why someone would seek to build a machine but state they have no time or inclination to build one.? . . . This seems to me you just like wasting people's time so you'll get no more from me I'm afraid. Good luck.!!

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I am clearly not expressing myself very well.
To be clear, your (and everyone elses) input is appreciated. I am taking note of it and it will not be ignored. I am not stupid, it is clear already that part of what I was proposing is silly. But that doesn't mean it was stupid to ask the question and it doesn't mean it was stupid to question to try to understand where the posters were coming from and try to put across another point of view.

You might have noticed that the last few posts were me discussing with ericks his ally framed machine?
You will not be aware that I spent part of my evening looking at steel prices and thinking about how that might affect the design. You will also not be aware that I also spent some time looking at whether a converted mini mill might suite me better. Until I actually start buying stuff nothing if fixed in stone.

Am I wasting peoples time? I thought this was a discussion forum for, errr... discussions?? With that in mind, thank you for your input so far, it is genuinely appreciated (apart from perhaps that last post), it would be a shame but I will not lose any sleep if you feel you don't want to contribute any more.

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Originally Posted by ericks

This is the best pic i have atm showing the connectors

Attachment 27078

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Thanks, I think I have come across that sort before but will have another look.

My first router was made from MDF. Look for references to "JGRO" with Google - lots of people have built them. It may be OK in the warm dry areas of the USA, but in a British climate in an unheated garage it has the structural integrity and long-term stability of cold-rolled cow dung. I built that machine (and around 7 years ago, it probably cost no more than £500) before I found this forum and based on glowing reports from people who had built one. I also saw a similar machine built from ply at an exhibition at about that time, which persuaded me to have a go. And, yes, it did do the job I built it for (basically, house-sign style of engraved plaque) and it built a number of models for my son's architecture degree. It is now firewood. I went steel for the mk2. Not sure why you talk about it not being very "modifiable" - angle grinder with cutoff wheel and a MIG welder and away you go. I wrote it up on this forum (search for "AVOR") and if you look closely you can how crap the welding is. Grown men have cried when they've seen it. Do you know, though? It's a bloody marvellous machine that continues to please me every time I use it. Probably cost around £2500 all told. Prices don't go down that much as the machine gets smaller although these days I would source more from China which would cut costs a bit.

Hey, there's a whole range between toy and carved-from-concrete machines that some guys here build. I had a go at the first as well as something half-way through that range and I don't regret my early learnings. But I am glad that I had half an eye to the future and did buy a decent spindle, steppers and stepper drivers for the mk1 that could be reused. Even if that first machine bent under the weight of the spindle even before starting to cut!

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Originally Posted by Neale

My first router was made from MDF. Look for references to "JGRO" with Google - lots of people have built them. It may be OK in the warm dry areas of the USA, but in a British climate in an unheated garage it has the structural integrity and long-term stability of cold-rolled cow dung. I built that machine (and around 7 years ago, it probably cost no more than £500) before I found this forum and based on glowing reports from people who had built one. I also saw a similar machine built from ply at an exhibition at about that time, which persuaded me to have a go. And, yes, it did do the job I built it for (basically, house-sign style of engraved plaque) and it built a number of models for my son's architecture degree. It is now firewood. I went steel for the mk2. Not sure why you talk about it not being very "modifiable" - angle grinder with cutoff wheel and a MIG welder and away you go. I wrote it up on this forum (search for "AVOR") and if you look closely you can how crap the welding is. Grown men have cried when they've seen it. Do you know, though? It's a bloody marvellous machine that continues to please me every time I use it. Probably cost around £2500 all told. Prices don't go down that much as the machine gets smaller although these days I would source more from China which would cut costs a bit.

Hey, there's a whole range between toy and carved-from-concrete machines that some guys here build. I had a go at the first as well as something half-way through that range and I don't regret my early learnings. But I am glad that I had half an eye to the future and did buy a decent spindle, steppers and stepper drivers for the mk1 that could be reused. Even if that first machine bent under the weight of the spindle even before starting to cut!

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Thanks Neale. I had a quick look at JGRO and have to admit the design horrifies me for something that needs to be rigid. But I have already been beaten into submission by jazzcnc so will not be going down the wood route anyway. Well, I don't think so anyway..... ;)

I have also had a quick read of the frame build on your AVOR. If you think your welding is bad you haven't seen mine! One thing I liked from your description was “If you can’t build it accurately, make it adjustable!”. This is something I have been thinking about but have not come up with anything I am happy will not affect rigidity other than semi-perminent epoxy. I do like your comments on epoxy though and that somehow makes it less daunting to me although I am still concerned it might be a lot of faff to get right.

I've followed a similar path the Neale, the first machine was a useless plywood and MDF contraption that at least proved I was capable of puling all the components together into a working machine. The current design is a steel frame which is mostly bolted together though the second gantry I built for it is welded using a dirt cheap stick welder that I bought for the job having never welded before. I used a technique I call 'bird poo' welding due to it's appearance. Grinding down the lumps and smoothing things off with car body filler followed by a coat of paint hides the evidence! It works fine.

I managed to source all the steel from the local tip so it was a cheap option for me! The design of the machine was partly dictated by the available material.

I followed Neale's excellent advice about making everything adjustable and the trick then is working out how to measure all the errors in a systematic way to isolate each source of error. There's still more to do but it's getting better in stages. I'm only cutting wood so my ultimate target accuracy is to put the tip of the tool where I want it be within a whopping great margin of 100 microns.

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Originally Posted by brman

But I have already been beaten into submission by jazzcnc so will not be going down the wood route anyway. Well, I don't think so anyway..... ;)

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Well, my work here is done then.! . . . . Some times people need to be given the shock n aww treatment to get them to listen. My only aim is to help not only you but others also reading this post. If other long term members of this forum are honest they will tell you a lot of what they learned or machine designs they use or some version of it came via me or the person they learned it from got it via me.
ie; "Building in lots of adjustment". "Buying quality components to save money". "Using steel and epoxy" " Mixing Steel n profile" " High sided machine frames rather than flimsy gantry sides" among others.

Also, I doubt those that started with wood/Mdf, or bought a shity component package, knowing what they know now would do it again or advise anyone else to do the same even if they did learn from it. . . . We don't drive cars with stone wheels because our cave-dwelling brothers learned how to build the wheel do we.?

So it's your choice if you choose to ignore my advice because like you, I won't lose any sleep if you do ignore it. But I guarantee you will have several sleepless nights and hair-pulling frustrations if you do proceed and try to cut corners or not listen to those with experience. Again good luck.!

Just to show it can be done - Lego CNC machine.

But I don't think anyone would recommend it! It's great that you picked up the point about adjustability from my other thread but as Jazz says, it's something I learned from this forum. I believe that my machine had an idea or two of my own - don't think I've seen another gantry design where the ballscrew runs through the end uprights, for example - but I'm not entirely sure that I might not have seen that somewhere. I shamelessly picked ideas from many other machines/build logs. That's probably my strongest recommendation.

Remember - copy one person's ideas and that's plagiarism. Copy many people's ideas and that's research!

"Imitation is the sincerest form of flattery"

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Originally Posted by Kitwn

I've followed a similar path the Neale, the first machine was a useless plywood and MDF contraption that at least proved I was capable of puling all the components together into a working machine. The current design is a steel frame which is mostly bolted together though the second gantry I built for it is welded using a dirt cheap stick welder that I bought for the job having never welded before. I used a technique I call 'bird poo' welding due to it's appearance. Grinding down the lumps and smoothing things off with car body filler followed by a coat of paint hides the evidence! It works fine.

I managed to source all the steel from the local tip so it was a cheap option for me! The design of the machine was partly dictated by the available material.

I followed Neale's excellent advice about making everything adjustable and the trick then is working out how to measure all the errors in a systematic way to isolate each source of error. There's still more to do but it's getting better in stages. I'm only cutting wood so my ultimate target accuracy is to put the tip of the tool where I want it be within a whopping great margin of 100 microns.

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So did you use profile rails or supported rails? And did you use resin to level or some other technique? Just curious about different options :friendly_wink:

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Originally Posted by Neale

Just to show it can be done - Lego CNC machine.

But I don't think anyone would recommend it! It's great that you picked up the point about adjustability from my other thread but as Jazz says, it's something I learned from this forum. I believe that my machine had an idea or two of my own - don't think I've seen another gantry design where the ballscrew runs through the end uprights, for example - but I'm not entirely sure that I might not have seen that somewhere. I shamelessly picked ideas from many other machines/build logs. That's probably my strongest recommendation.

Remember - copy one person's ideas and that's plagiarism. Copy many people's ideas and that's research!

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Yeh, but there are so many build logs and youtube videos out there so it is deciding what to copy that is the problem. After all, there are a fair few wood machines that people appear to be proud of :whistle:

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Originally Posted by Neale

Just to show it can be done - Lego CNC machine.

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All I can say is some people just have just too much spare time!... Lol

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Originally Posted by JAZZCNC

The only place for MDF in CNC for lighting fires to keep shop warm

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I wouldn't even burn MDF, it has some nasty stuff in it!

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Originally Posted by brman

Yeh, but there are so many build logs and youtube videos out there so it is deciding what to copy that is the problem. After all, there are a fair few wood machines that people appear to be proud of :whistle:

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Ah, now - that's an easy one to answer! Just decide what you want to do with it, what do you really want to be able to do with it. Subject to affordability, everything else follows from that!

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Originally Posted by brman

So did you use profile rails or supported rails? And did you use resin to level or some other technique? Just curious about different options :friendly_wink:

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I used 20mm fully supported rails as they are cheaper and much more tolerant of alignment errors than Hi-Win. Despite coming off the tip the 65mm box section steel the long axis is mounted on looked flat enough to me and my 1m steel ruler so they are directly mounted onto the metal. The gantry is 2 pieces of 50 x 100 mm box welded together and though the surface seemed much flatter than I would have expected I used epoxy to level the face. Unfortunately this was before I knew about the West Systems 105 resin and 209 hardener combination and my chosen goo was too viscous. The result is probably worse than the underlying metal and will be re-done during planned upgrades later this year once we get into winter and the shed daily maximum temperature drops below 50C.

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Originally Posted by Neale

Ah, now - that's an easy one to answer! Just decide what you want to do with it, what do you really want to be able to do with it. Subject to affordability, everything else follows from that!

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I think that might be the crux of the problem. What I really want is a machine that will do anything, including taking the place of a conventional milling machine. I am unlikely to get that though.....

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Originally Posted by Kitwn

I used 20mm fully supported rails as they are cheaper and much more tolerant of alignment errors than Hi-Win. Despite coming off the tip the 65mm box section steel the long axis is mounted on looked flat enough to me and my 1m steel ruler so they are directly mounted onto the metal. The gantry is 2 pieces of 50 x 100 mm box welded together and though the surface seemed much flatter than I would have expected I used epoxy to level the face. Unfortunately this was before I knew about the West Systems 105 resin and 209 hardener combination and my chosen goo was too viscous. The result is probably worse than the underlying metal and will be re-done during planned upgrades later this year once we get into winter and the shed daily maximum temperature drops below 50C.

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Thanks, more food for thought.

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Originally Posted by brman

I think that might be the crux of the problem. What I really want is a machine that will do anything, including taking the place of a conventional milling machine. I am unlikely to get that though.....

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I can tell you for certain you won't get that, not even for real money!

As I've worked my way through the collection of threads here it's noticeable how many of the serious router builders already have a manual milling machine which they use to good effect when building a CNC router.

Kit

PS. On reflection, a 'machine' that can do anything is called a 'workshop' and contains a variety of tools each designed to do a limited range of tasks well. Building a really good workshop is definitely a project of it's own and can take many years.

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Originally Posted by Kitwn

I can tell you for certain you won't get that, not even for real money!

As I've worked my way through the collection of threads here it's noticeable how many of the serious router builders already have a manual milling machine which they use to good effect when building a CNC router.

Kit

PS. On reflection, a 'machine' that can do anything is called a 'workshop' and contains a variety of tools each designed to do a limited range of tasks well. Building a really good workshop is definitely a project of it's own and can take many years.

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Yes, I realise that. It has taken years for my workshop to get where it is and in reality it is still a small garage which is already severely lacking in space but still lacking in machine tools. I do have access to a bridgeport mill but it is not practical to use that for regular stuff. Hence the idea of building a small router style machine in a fairly rough and ready way but one that is capable of cutting ally so it can be used to upgrade itself (or, more likely build a better one).
The alternative is to bite the bullet and rationlise my garage so I can fit one of the larger mini-mills, cnc that then think about whether I still want a router style machine.

One day I'm going to retire to a place where the nearest Bridgeport mill is less than 1300Km away. It won't be for a few years yet I'm afraid. Do the best you can and live with it.

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Originally Posted by Kitwn

One day I'm going to retire to a place where the nearest Bridgeport mill is less than 1300Km away. It won't be for a few years yet I'm afraid. Do the best you can and live with it.

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Ha, and there is me complaining that I have to drive 20 minutes to a mates house to use a bridgeport
:witless: