Please help with this build Albert

[bigal999]

Hi I have the supported rails already but I am not sure if z axis should be as close to the gantry of y axis or not
Albert

[Doddy]

I agree with routerdriver about LinuxCNC. If you're building a basic machine then it's easy to install and set up using the included wizards. No delving into the depths of Linux complexity at all.

I agree - but then the line between basic and ...not-basic can be particularly difficult with LinuxCNC for a novice to understand. Part of the reason I squint at it hard is understanding the point beyond which you abandon the wizards and take responsibility for the management/maintenance of your configuration files. To the uninitiated that's a whole lot of pain to research to get correct, not to mention having to crank out home-built HAL components (I've a sleepy memory of coding a particular logic component to support a push-On/Off & Reset moding of an illuminated push-button and .. something else (too tired, cold to go to the shed to confirm) that you hack-and-restart, and repeat. That, and the whole GTK/Glade options to add to the screen-set (which is poor, as stock) and the quirkiness of not being able to manually traverse axis (and from memory that also impacts the MPGs/encoders) when on the MDI page... and don't get me started on the GUI stealing HMI events when running Andy Pugh's lathe macro set.

What I'm trying to say is it's less polished than other control software. And for a novice it is a steep learning curve. I stand behind not recommending it as an entry-point to CNC.

edit: Aha, HAL components - the aforementioned Push button (resettable toggle), check-set-for-n-cycles (to determine a stable spindle-at-speed), a resettable run/pause/stop control (together with driving LED status for each state) and.... something else that I forget again. You could do the above with combinational logic, but that just makes your HAL file brutal.

[JAZZCNC]

I agree - but then the line between basic and ...not-basic can be particularly difficult with LinuxCNC for a novice to understand. Part of the reason I squint at it hard is understanding the point beyond which you abandon the wizards and take responsibility for the management/maintenance of your configuration files.

Well never thought I'd say this about Linux CNC and it's hard to cough up the words.!! . . . But having recently setup a Plasma machine with THC and Mesa cards which is a fair bit beyond basic I realised that on a Basic level ie: Using the wizards that setting up a basic router, basic being motors, E-stop, limits and homes with spindle speed control and even dual axis homing is no more difficult than any other software even for a complete novice.

BUT I agree with you Doddy that ounce you want to go beyond that then it gets very deep and can be frustrating as hell when you have to dive into the Hal and Ini files and a bit of Python etc'.
It's very different to other control software in how it works internally and not for the faint hearted when you get into the Hal, personally I struggled for a while until it clicked but you have to remember I'm very experienced with CNC and macro writing etc. and now it makes much more sense, but for a complete newbie with no experience then it's going to be a huge task for anything past basic which the wizards don't provide, of which there are many things which I consider basic that the wizards don't provide and should ie: DE-bounce.
To apply DE-bounce to a pin requires you dive into Hal and code it.! In any other control software that would be tick box at the time of setting the pins. It's these little things missing from the wizards that let Linux CNC down IMO for the more novice users.
However, the power it puts in your hands is impressive when you get into the Hal etc, esp with Mesa cards as virtually anything is possible if you have the time to figure out the code.

Would I advise Albert to try it.? then YES because it's free so got nothing to lose. Set it up on the bench with £5 BOB and give it a go.!

[Clive S]

To apply DE-bounce to a pin requires you dive into Hal and code it.! In any other control software that would be tick box at the time of setting the pins.

Yes but just ticking a box does not let you change the parameters like the time delays .

Yes it is very simple now to set up a small standard mill or router or even a lathe in a few minutes with a P/port card or better still a mesa card.

In fact I retro fitting a Boxford 160 lathe with ATC just using a P/port.

Linuxcnc is simple to download an ISO then write it to a USB bootable in 15 minutes.

[bigal999]

Trying to work out my design but need some answers to get me started.
1. Y axis side plates if I use 15mm aluminium plate how wide will it have to be.
2. Y axis is 600mm wide can you give me an idea how deep the gantry plate would be if I used 15mm aluminium plate.
3. How deep would X axis plates need to be the length is 1000mm and would be 15mm aluminium.
4. If this costs out to expensive. Could I use steel plate and what thickness would I need.
Albert

[Kitwn]

Well never thought I'd say this about Linux CNC and it's hard to cough up the words.!! . . .

Try your best lad, it'll make a man of you!

In recent years there seems to have been a bewildering array of possible hardware and software produced for controlling your new machine and some of it is as expensive as the rest of the machine. This is not entirely inappropriate, these are important components, but the option to get things moving with some free software and a cheap breakout board while you spend most of your heard-earned on the bits that are not so easily and cheaply upgraded is the strength of the LinuxCNC/cheap parallel BoB combination in my opinion.

Once you have a working machine that can make things for you, then comes the time to delve into the other options available and decide what added features you really want to have.

[Kitwn]

Hi I have the supported rails already but I am not sure if z axis should be as close to the gantry of y axis or not
Albert

Don't waste the bits you've already bought, there are plenty of machines working to the full satisfaction of their owners using these rails. Mine for example. You can see the arrangement on my current build log.
If you're really worried there are designs using these rails mounted along the top and bottom of the gantry with the ballscrew behind, rather than with everything on the front like mine. One of the build logs on here has one I think, but it makes the Z axis more complex to build and the Y axis more difficult to align. You will also need to increase the height of the gantry above the bed. It's all about the compromises you're willing to make and the workshop facilities you have.

[JAZZCNC]

Yes but just ticking a box does not let you change the parameters like the time delays .

Yes it is very simple now to set up a small standard mill or router or even a lathe in a few minutes with a P/port card or better still a mesa card.

Clive, I kept it simple just to make the point but just about every other motion controller software I've ever used gives you the option to apply De-bounce by clicking an option and setting the amount of De-bounce. You don't need to go into any files and write 3 lines of code for such a simple thing was my point, it would be an easy thing to add to the wizard and I don't know why they don't.
It's these little details that spoil it to me and I suspect puts new users off, because once you leave the realms of the basic wizard is when the shit hits the fan and things go tits up for most new users... But we've had this conversion many times so I l know you don't agree...Lol . . . But you don't see many new users turning to Linux CNC or put another way if they do, there's a reason why Mach3/4 and now UCCNC are so popular.!! .... on which I rest my Case......

[bigal999]

Just a quick few questions stuck on my design
1. When joining into the end of 15mm aluminium should I use 8mm or 6mm Allen screws and how deep into the aluminium should I tap the hole.
2. When joining 15 mm aluminium 125mm wide how many screw do I need
Albert

[routercnc]

In the end you would need to decide what works in your design but based on the information provide I would do the following:

8mm screws (there is still plenty of material left in the 15mm plate). 8mm are tightened to a higher torque so your clamping force on the joint will be much higher. Plus the heads are larger so make better contact with the piece they join to. You need to check the other material can accommodate the size of the head if using cap heads and they are countersunk.

Anything deeper than about the 1.5 x D for threads does not improve the joint. 1.5 x 8 is 12 so drill min 20 and tap to min 14 to allow you to use M8 with 12 mm engagement.. If you have a bottom tap you can drill a bit shallower but make sure you can tap enough whole threads.

For 125mm width I would choose 3 screws if the design allows. We could go into joint calculations and stress triangles but I’m not sensing you want to go there so at least 2 and ideally 3. One would be in the centre and the outer 2 would be set in around 15mm or so from the edge.