Time for a Reality Check and encouragement to New builders.!

[Neale]

If all you want to do is build a good, functional, CNC router, then I absolutely agree with you, Jazz. For example, despite the fact that the usual minimum steel section that people seem to use is 60x60x5 - minimum! - my machine is built from 50x50x3, and it seems plenty strong enough to me. There does seem to be a lot of over-building going on. Maybe I'll be proved wrong later...

As I mentioned in the "epoxy levelling" thread I started, my welded steel frame, with its 1.5mm or so dip in the X rails, would be perfectly usable after one coat of levelling epoxy. No question, and I've said as much in that thread. One of the reasons I have spent time measuring is just to verify that. However, I'm retired, I'm not doing this to make money, and at various times I've described myself as an engineer, a mathematician, and a scientist. Wearing my engineer's hat ("an engineer is someone who can do for five bob what any damn fool can do for a pound") I'm right beside you. Swapping to mathematician/scientist, though, I can't help asking "How? Why? What?" In other words - that looks interesting, I wonder if...? We can apply scientific method to building CNC routers, or at least aspects of their design and construction, and maybe something useful will pop out. Or maybe it won't. Is it useful to suggest, based on what I see at present, that two thin layers of epoxy might be better than one thick one? But that one will be good enough for most practical purposes anyway? You are also quite correct that I don't know exactly how accurate my measurements are, although in the best scientific tradition I've described how I made them, and also tried to double-check the method. Is that better than proceeding in ignorance? My father was always saying, "You do it like that because that's how I've always done it." I've always had a problem with that attitude...

I'm also quite convinced that nothing I can say will change the views of anyone else anyway, but in a nice, quiet, corner of the forum us airy-fairy types can argue pointlessly amongst ourselves without disturbing the real workers

BTW, I also do listen to other opinions, if they're backed up by reasonable evidence or results. That's why I have a CSMIO/IP-M and three EM806 on order for the new machine to replace the vanilla BOB and analogue drivers I was going to salvage from my old MDF-built router. I wouldn't even bother measuring accuracy on that machine - by the time you've pulled the tape measure to the end of the bed, the starting point has moved...
Oh, and there's a big smiley face to cover this whole post - I just can't find one big enough! I am very grateful to all who have posted here in the last couple of years and from whom I've learnt a lot.

[EddyCurrent]

I think part of the blame is the way the forum works, the same questions keep cominmg round e.g. MDF built machines.
It would be better if there were discreet sections where discussion could take place, for example, 'Router Frames'
In that section there would be discussion to the n'th degree about frames, new users could take a look and use information to build their own frame to whatever level they wanted. There would be no posts like "MDF frames are shite" because there would be a sub section under 'Router Frames' for that. Same would apply to other components of the machine.
Things like Rails, Spindle, etc. would have their own sections.

Router Type Machines
. Frames
... Steel
... Wood
... Aluminium
Gantry
Bed
Z axis


Edit: I'm thinking back to my Lego machine idea where you pick'n'mix your parts from the various sub sections of the forum.

For example I would submit drawings for my frame and gantry for anyone to download, tweak, build but at the moment I think they would just get lost in the mountain of info.

[JAZZCNC]

If all you want to do is build a good, functional, CNC router, then I absolutely agree with you, Jazz. For example, despite the fact that the usual minimum steel section that people seem to use is 60x60x5 - minimum! - my machine is built from 50x50x3, and it seems plenty strong enough to me. There does seem to be a lot of over-building going on. Maybe I'll be proved wrong later...

Exactly my point it's more than enough for 95% of DIY builds and you won't be proved wrong I'm 100% sure of that.

Swapping to mathematician/scientist, though, I can't help asking "How? Why? What?" In other words - that looks interesting, I wonder if...? We can apply scientific method to building CNC routers, or at least aspects of their design and construction, and maybe something useful will pop out. Or maybe it won't. Is it useful to suggest, based on what I see at present, that two thin layers of epoxy might be better than one thick one? But that one will be good enough for most practical purposes anyway? You are also quite correct that I don't know exactly how accurate my measurements are, although in the best scientific tradition I've described how I made them, and also tried to double-check the method.

Nothing wrong with Scientific and taking measurements etc but completely pointless if it can't accurately be verified and at this size of machine then it can't be with a spirit level and tape measure!! (Making a point not having a go at you there.!). . . . BUT I can tell you what will tell you 100%.? Cut something with the bugger.!!

If it's out then it will just mean simple case of shimming or adjustment if you have had the good sense to build adjustment into the machine.
This is what I mean about good design beating over building every time at DIY level. Also lets make no mistake we 99% of members are DIY level no matter what those up there own arse's like to think.

[mitchejc]

Jazz, I totally agree with what you are saying. I got on here a few months back with the intention to build a small very sturdy router from alu and after calculating the cost and seeing the nice solid steel builds and not fully understanding remarks like "use larger profile" and "extra weight might be a good", things got out of hand... You over design one bit and then you strengthen something else to be in line with that and before you know it your are caught up in a viscous cycle of adding more strength and weight. The other issue is that parts are MUCH larger in real life than the CAD drawing suggested but at that point its a bit too late. I did not see this coming but to give you a good example, I had to fit a hook to the roof trusses and buy a chain block just to get my gantry on an off my machine while I'm building it, so how wrong is that for a little DIY router. Well, for me there's no turning back now and it will be finished like that and maybe I can do a future version 2 in a more sensible manner.

I wish someone could get hold of a drawing of the Datron M8 gantry and post that on here as a reference of what the ultimate steel gantry looks like. I bet you one does not need a chain block to lift that gantry.

I think classifying the build threads into 4 classes: Wood, Alu, Steel and OTT Wackjob is a good suggestion.

[Clive S]

Jazz, I totally agree with what you are saying. I got on here a few months back with the intention to build a small very sturdy router from alu and after calculating the cost and seeing the nice solid steel builds and not fully understanding remarks like "use larger profile" and "extra weight might be a good", things got out of hand

Etc etc. I for one agree completely that if you're not careful things can get a bit out of hand. Its alright trying to measure to the nth degree in the morning and then when the sun comes out in the afternoon (or in the case in England when the big wood burner gets going) the whole machine has expanded and the first lot of measurements go out the window.

I do realise that different people see things in different ways but as Dean has pointed out we have to be careful not to put people off in what is achievable to the average Joe Blogs trying to build a machine in his garage with just basic tools and I would suspect there are quite a few folk out there wanting to build a machine having never even been in a true machine shop.

I could not have built my router without the help of some of the truly helpful guys on here.
So lets keep it light. As this forum is a mine of information and I have met some really nice and genuine people on here. Happy New Year ..Clive

[mitchejc]

Well said Clive In the end most of us are building and using these machines for pure entertainment value whether its a little 6"x 6" mdf router with old hard drive steppers or a 3x2m monstrosity, as long as everyone is having fun doing it, all is good. As soon as I have finished this ice cold beer you subtly suggested I'll be back in the shed to continue bolting the battlestar galaxtica together and I sure as hell hope I don't discourage anybody else to pursue there cnc dreams by doing so :-)

[Ross77]

Had a bad Christmas Jazz? :0)

Before this gets really catty would it not be an idea to turn it in to something more positive and usefull like a standard design for a 2.2kw router? Yes I know work size will affect slight sizing but most common size could be used?

Ive been on and off this forum for about 5 years and the same questions and basic mistakes are made time and time again. My pet hate is poor bracing layout and over sized bracing, nearly every initial frame design the same comments have to be made.

Rather then keep on about it I think it would be better to do a little Guide that that everyone can added to, to make it a varied and trustworth source rather than one persons opinion.

Its it more the projects that become large due to "advice" or when large projects are proposed from the outset?

[JAZZCNC]

Removed has to Reply in anger means to repent at leisure.!!

HAPPY XMAS and NEW YEAR to ALL.!

[Ross77]

Sorry you have a bad time Jazz. Look none of my comments have been meant as an attack on you. Whilst forums are really good at helping they are not the best form of communication and a simple difference of opinion can be taken out of context.

I work in design office and we always bounce ideas and comments off each other and the value is working as a team, sometimes my ideas are good and sometimes another persons is better. I don't take it personally its just how it is.

Happy to post up some ideas like i always have when I have the time to be on here.

I really don't want to fall out with people on here and if I do have a difference of opinion then I will give a justification for it and not just say that's "shite". I also only comment on the structural elements that I'm confident advising on. It is also just a difference of opinion and not a personal attack and I think that's the main point and the more opinions the person asking the questions gets then the more helpful it is.

Anyway all the best and hope you can help me out with the bits im not so sure about.

Cheers
Ross

[vargai]

Whilst forums are really good at helping they are not the best form of communication and a simple difference of opinion can be taken out of context.

Actually you are taking about how you could provide better ministration for the forum members and that is great.
You and the the available data here give huge help for 1st time and advanced builders and you do it magnanimously.
As human beings, we all have our own values, beliefs and attitudes and personally I do not mind both gentle and tougher comments.
Sometime a virtual slap comes in handy to halt i.e the l'art pour l'art design as I did myself.
Regarding to the receivers no one should use only the paste command in design and devolve the responsibility of the result.
All of us have to have common sense to make wise decisions and spent our money usefully.
So this is an exciting great forum and happy to have found here.
So keep your good habit and

Happy New Year to all.

PS: these girls do not prevaricate