New build – input/comments appreciated

[JAZZCNC]

Seeing it from this perspective you'd be right - but my personal opinion is that limit switches are not only unnecessary but even give a deceiving sense of security they cannot provide:

I agree upto a point but here are some cases they are required. Servo's for instance will just take off at full speed if there positioning system fails or gets interupted. So in this case they are very much required.

Also with small fast router machines it's very easy to jog from one side to the other which can result in banging into end stops etc often. Esp when first learning. Again I agree a machine that breaks with just a small limit crash is Crap but enough of this banging and eventually damage will occur so best avoided and for just a few sheckels more is it really worth not having.??

What sometimes makes sense is reference switches to automatically home the machine. But even though they can make life a bit easier in some situations they are rarely necessary:

[LIST][*]Usually you clamp your workpiece just anywhere on your machine and need to touch it off anyways because your machine has no eyes.

• In this case knowing machine zero is absolutely pointless - it is just a set of numbers without any meaning for the actual machining process.
• Only in case of step losses it can safe you a little time to get back to the correct workpiece zero - if your workpiece isn't destroyed anyways which will most likely be the case... And a machine losing steps regularly enough to make you want homing switches is again just crap or badly set up ;-)
• But even in this case you can usually just touch off again (if the reference edges are still available)...

[*]Reference switches are only necessary if you have things like tool changers, tool length sensors or fixed clamping devices on your machine. [*]And: if the switch isn't precise (or a chip gets in between) machine home will also be imprecise accordingly. Many cheap homing switches are much worse than touching off the workpiece.

This I mostly Disagree with.!!

Homing switches are THE most useful thing you can put on your machine. I'll give examples to why.

Only yesterday I was cutting parts in large expensive sheet of aluminium when the cutter broke. The part wasn't damaged but it was my last cutter so the Job was stopped. The corner of the material where I choose Work Zero had been cut away. So how without Home switches do I get back into absolute position when my reference point is gone.?
Yes I could go back into Cam and choose some hole to re-reference from etc but this all costs time and effort. Home switches provided resonable quality remove all this hassle.

Example #2 Same large piece of material and Large Job with multiple parts nested into material. So large I don't have time to do in one sitting. Again Zero ref has been cutaway. Home switches allow me to pause the Job or break the Job into smaller jobs and still quickly get back into position.

There are other examples like power cuts or PC crashes etc that back the need for Home swithces but again for the small cost it's silly not having them.
The only thing is that if you need high accurecy homing then you need Good Home Switches. I find even your Cheap Chinese Proximity switches are more than good enough for 99% of Routers or DIY'ers using Milling machines.

So for the Small cost and the fact Limits and Homes can share the same switch it's Stupid not to have them.!!