Quote Originally Posted by Boyan Silyavski View Post
We all have right of opinion. I dont promote anything. My opinion is that when you spend 3000 on a machine is false economy to save 100 more on material which will raise your machine to whole new level. You call that overbuild, i call that "ability to make more juice from one orange"
That's my whole point.!! . . . It's not just the material is it.? . . Lets look at You monster which is using servo's correct.?

Even the cheapest servos are 2 or 3 times the price of stepper motor and drive. Then you have the fact that Servos require high pulse rate to get there full speed and resolution. If not then your using electronic gearing which is wasting resolution of the encoder which you paid for and lessens the advantage of servos.
This then means a good external motion control card with at least 500Khz frequency for typical 2500ppr encoder is needed. Far more than the lower end ones like Pokeys, usbcnc or even Cslabs IP-M can offer. This also then means a quality BOB which can process high pluse rates, lots of the cheaper ones can't do this.
You also have the fact servos are very much more affected by electrical noise and require much higher attention to detail on the wiring side. Quality cables are needed and filtering for power etc and the list goes on and on.!! . . . . This is the TOTAL cost of over building.

Many won't do this and will suffer the price in some form or another. Often it's low speed/accuracy or unrelaibilty.!

Profile I DO USE for machine this size is 120 x 80 or 160 x 80 and arranged in "L" shape and can tell you now it doesn't bend even in Heavy use. Yes like anything it will bend if enough force is applied but still it's more than strong enough for any wood router or even one that's cutting aluminium.

It's also nearly 1/3 the weight of 200 x 100 x 5 RHS and not nearly has resonant. Initial Cost is more than steel but the time saving and less treatment required balances this out in the end.
Gantry sides etc are irrelavant even a steel machine will need these if designed that way.!

Also just to clear things up I'm not trying to stop you having an opinion. I'm putting my opion across and saying that what your promoting with your "Must use Steel to be strong" opinion isn't exactly true or even correct if not properly implemented and follwed up with correct components through out the machine. This you don't seem to mention often when preaching use steel.?

So I say what I do for the sake of those who see your posts and hopefully don't go blindly into something they haven't been made aware of by the preacher.!!