Re: Axis not working properly
Quote:
Originally Posted by
JAZZCNC
The cost and difficulty will depend on how you want to do it.?
If you just want to do it the cheapest way then fit just HOME switches and use the Cheap Micro switch type. You can then setup SoftLimits to protect you from crashing into the sides etc.
The Microswitch type is not as accurate and more easily damaged than the proximity type but they are cheap and will mean you can get away without requiring a 24Vdc PSU and use the 5V PSU in the control box. However, they are more prone to interference and less accurate.
These switches you can buy from £1 each up to £50 depending on quality, size, etc. You'll also need a 3 core shielded cable which will be about £1 - £2 per meter.
The next method is again to just fit HOME switches but use proximity type. They offer more accuracy and are less prone to damage, the downside is they require 6 to 36Vdc to work so your 5V won't be enough so will require another PSU, 12 or 24Vdc are usually used, 24Vdc is the better option as it provides better immunity from electrical interference.
These cost around £5 each and the 24Vdc PSU will be between £10-£20. Again 3 core shielded cables will be required.
The third method that won't cost much more money but will require more work fitting is to use Proximity switches that travel with each axis and work as both HOME and LIMITS.
They do this by sensing a Target located at each end of the machine when working as limit switches while cutting etc, but when HOMING the LIMITS are ignored as it slowly travels towards the Target so the danger is limited.
The last method but the best method and most costly method is to fit both separate home and limit switches.
This can be done with a mixture of cheap Microswitches for the LIMITS with a fixed switch at each end of the travel which doesn't need any accuracy. Then fit higher accuracy switches for the HOMING, these can be either fixed or traveling.
Now for a machine this size then I would say just fit proximity HOME switches and let the soft limits protect you from crashing. This way you have better HOMING accuracy but keep the costs down because you won't require as much wire. You will however need the 24Vdc PSU.
If you are on a tight budget and don't require better accuracy then do the same but using Micro switches and the 5V supply you already have. You'll do this for under £20.
Any of them is far better than not having any at all and Soft limits work very well but require HOME switches to work properly as the Limits are set from the MACHINE ZERO position.
There is one other POOR MANS option that doesn't require any switches and will let you set MACHINE ZERO with some repeatability and along with SOFT LIMITS keep you safer and allow you to find WORK ZERO with reasonable accuracy.? . . . Run the machine slowly into the end stops and set REF ALL HOME at this position every time you start the machine or lose position thru crashing or E-stop.
It's crude but can be effective if the end stops are accurately lined up at each side.
Thank you for the explanation
Well I mean I haven't got a budget but I was hoping if I can get it under 100£ if I able to doit myself that would be great.
I would love to use the CNC soon as possible it's should be running a month ago to be honest and probably this weekends gonna be the first try.
Home button is a must I would say and the limit switches to.
Re: Axis not working properly
Great advice and well explained.
I definitely want to do some work done but I have no idea where to get this parts what is the recommended switches etc.
I'm happy to spend money on it and it's a piece of mind to.
Only I hope now it's not that difficult to do it so I can manage for myself?
I never done nothing like it before but it would cost lots of money to send the machine away to get this done.
As I said I'm kind of the user's side not for building machines but I'm happy to do myself if not to complicated.
So obviously if I start doing things like that probably my guarantee is over.....if I got any to be honest.
So you mentioned you selling those bits so could you send me a link where I can get those bits ordered?
And I find any tutorial videos for fitting those bits?
Re: Axis not working properly
Quote:
Originally Posted by
Georgehun
Great advice and well explained.
I definitely want to do some work done but I have no idea where to get this parts what is the recommended switches etc.
I'm happy to spend money on it and it's a piece of mind to.
Only I hope now it's not that difficult to do it so I can manage for myself?
I never done nothing like it before but it would cost lots of money to send the machine away to get this done.
As I said I'm kind of the user's side not for building machines but I'm happy to do myself if not to complicated.
So obviously if I start doing things like that probably my guarantee is over.....if I got any to be honest.
So you mentioned you selling those bits so could you send me a link where I can get those bits ordered?
And I find any tutorial videos for fitting those bits?
I will PM you regards the parts and give you my email. I'll gladly guide you thru setting up and the wiring side, it's not difficult.
The fitting side you will need to work out for your self because it's machine dependant where you locate them, when you have the switches in your hand it will be easier to see the best place to fasten them and where wires will run etc. You'll need to make brackets to hold them but they don't need to be anything fancy, just strong.
Re: Axis not working properly
That would be great
Thank you so much for your help.
Re: Axis not working properly
I just got a Ebay machine from the guy in Peter lee :whistle:
It all moves as it should but i now have to put home & limit switches on it.
Great post @JAZZCNC
