Backlash

[efinkg]

I have looked at prices of all the added benefits, and it looks like unless the motor mounts are going to run me over $30 per I come out ahead upgrading the motor and lead screw nuts for a separate cost. I'm not trying to be difficult and I appreciate all the help, I just want to ensure I am getting the best deal I can. I should probably email Taig to make sure I am not missing out on anything I should be worrying about.

[efinkg]

Hub,

I understand this also, I should take a look at the shumatech manual and see if I can do backlash compensation through that.

[hub]

Hub,

I understand this also, I should take a look at the shumatech manual and see if I can do backlash compensation through that.

That was for manual. For NC, backlash compensation works fine when doing straight left-right or forth-back moves, but doing circles & arcs for example you might not get what you want.

[lsces]

Hub,

I understand this also, I should take a look at the shumatech manual and see if I can do backlash compensation through that.

The DRO350 does not have anything other than straight display of the reading head. Using quadrature headers via the QCC100 just does a straight count and numeric output.

It would be possible to implement backlash compensation on the DRO550 and all the code for it is open source (opendro on sf ) but the current code just displays the values direct.

As for the base mill, there are a number of ways of buying the necessary parts. Personally I supply the kress spindle rather than the ER16 one, so don't need that anyway, but the price is such that a complete package is often easier to pick up. We don't see second hand ones often, since that would be the cheapest option, even if you then fit a new set of lead screws and nuts ... the parts are not expensive anyway.

[efinkg]

What is the difference between the Kress and ER 16 spindles? Mr. Werby of Computer Sculpture said that the CNC Ready mill cannot be used by hand. Is this true? Is this due to the adjustable leadscrew nuts or the lack of handles supplied?

[cameraguy]

What is the difference between the Kress and ER 16 spindles? Mr. Werby of Computer Sculpture said that the CNC Ready mill cannot be used by hand. Is this true? Is this due to the adjustable leadscrew nuts or the lack of handles supplied?

just the lack of handles. my dad uses one of my extras with hand cranks purchased separately and fitted back on. Just remove the motor mounts first.

[Jeff-Birt]

I've had several folks purchase the CR mill PLUS hand cranks. Then they have used it as a manual mill for a while before upgrading to CNC. The CR version of the mill comes with the much better spindle motor as well as the stepper couplers. Taig is now only supplying the split lead nuts so you will likely get them on either a manual version or CR. If you add up the cost of purchasing the upgraded motor and stepper couplers separate (and shipping them separately as the motor is heavy) you a little better off buying the CR version IF you might want to upgrade later.

[efinkg]

So I have spoken with Andrew Werby and he tells me that the motor mounts + couplers would be $106 and the larger motor $80. This is still less than the CR model, unless my math is completely off.

[efinkg]

Would models such as the Grizzley iGaging with remote display be good options for the Taig. I'm a little torn because I love the idea of the rotary encoders, it seems like a wonderfully slick way of mounting, but the sliding should be more accurate in theory, although these have a .001 accuracy so my mileage may vary. Reports seem to be pretty favorable, will I just be furious with them, having been used to things like Bridgeports with glass scales and a Hurco with 10,000 count encoders and ballscrews, or will they be plenty accurate for a Taig?

T21577 0-6" Digital Fractional Horizontal / Vertical Remote Scale

[lsces]

Would models such as the Grizzley iGaging with remote display be good options for the Taig. I'm a little torn because I love the idea of the rotary encoders, it seems like a wonderfully slick way of mounting, but the sliding should be more accurate in theory, although these have a .001 accuracy so my mileage may vary. Reports seem to be pretty favorable, will I just be furious with them, having been used to things like Bridgeports with glass scales and a Hurco with 10,000 count encoders and ballscrews, or will they be plenty accurate for a Taig?

The iGaging style scales are a good improvement over the earlier versions, and remove a number of the problems. When Scott has it back in stock, the DRO550 will take up to 5 of them and display them on it's LED display.

Re 'handcranks' - all the CR machines I've had came with handcranks ... must get around to making some sleeves up so they can fit the 1/4" shaft on the motors, and recycle them ... but the handles wit the drop down crank are a little safer when using CNC, and a few of my customers have fitted them.

[cyclestart]

Have an old computer (and monitor) kicking around and a bit of extra space in your work area ? This open source DOS software is worth a look:
DRO SOFTWARE

I've gotten as far as testing the system with rotary encoders, just the mechanical bits left to complete (waiting for the right salvage to come along lol). On my mill converting linear motion to rotary via timing belt won't be difficult, on a small mill mounting the extra pieces needed would take some planning. The software claims to do backlash comp, so reading directly off the lead screw should also work.

[fretsman]

Maybe a little off topic, but still along the same lines, I've heard different stories about using a cnc mill manually with the motors installed (with dual shafts) with crank handles on the back.

I haven't not used one like this, but is it correct that if you use it manually this way, with the motor cables still connected, that it can actually become a generator and burn out the drives? It makes complete sense so I would think just disconnecting the cables would be fine, yes?

Thanks,
Dave