Sieg SX3.5 DRO Choices?

[IanTParticipant @iant]

Looking at adding DROs to my SX3.5ZP and wondering the best route to take. I’m aware that M-DRO offer both 2 & 3 axis kits for this mill (at a price). The 3-axis kit only measures head movement, not the spindle. Obviously there are also other options such as Touch DRO and kits direct from China.

So two questions really.

First – Your DRO recommendations generally.

Second – I’m not sure I see too much point in just adding a Z-axis scale to measure the head movement – especially with the powered head on the ZP. However, I do find the built-in spindle scale very hard to see (I have poor ‘contrast’) So I’d very much like to have the spindle movement (as opposed to head) as the third axis display. Has anyone come up with a good solution to this problem? Otherwise, I might just stick to 2-axis.

Regards,

 

IanT

[duncan webster 1Participant @duncanwebster1]

Sooner or later you’ll want the third axis, so buy the 3 axis display even if you only use 2 to start with.

I bought mine for both lathe and milling from MDRO. A bit more expensive, but much better aftershaves than buying from China

[JasonBModerator @jasonb]

The best option would be a 3-axis display and 4 scales with the Z & Quill set up to “sum” that way you can always keep track of the Z height. Handy when working on larger items or you need to move the head to change tooling. M-Machine do displays or an extra unit that will allow the summing but may not be part of their standard kit.

I think the 3.5 uses the same quill readout as my 2.7 in which case it would not be hard to replace the Scale that gets pulled out as the quill extends with a piece of bar that a magnetic strip could be bonded to. Take out the existing display and use the space to fit the read head for the magnetic strip.

When I first fitted a DRO to my X3 I used an M-machine one and just bought X&Y scales but with a 3-axis display. Did not take me long to see that having the third scale on the head was a must.

[Peter Cook 6Participant @petercook6]

Ian, I added a 3 axis DRO to my much smaller SX1LP. I purchased  the appropriate optical scales and a head unit as a kit from Ali express. All up it came to just over £200, even though I made a mistake and ordered 1 micron scales. What came worked well, although it needed  work to attach the scales to the mill – there was just a basic set of brackets in the kit so mostly I made my own.

On my little mill the quill action moves the motor plate and base of the head. I was able to connect the Z-axis read head to the bottom of the head so that it shows both Z axis movement and quill movement. The linkage and the head is not particularly rigid (but then it is a VERY small mill), so that If I lean on the head the readout changes 10-20 microns, but letting go allows it to go back. If you can engineer a link from the quill to The Z scale it is useful.

There is a bit of a write up on the Western Thunder site

[IanTParticipant @iant]

Yes, I’d considered getting a 3-axis display but only X/Y scales…keeps the cost down a bit and can be upgraded if required. I have also looked at Touch DRO but I think it would be more effort to implement overall and I’m not sure (for my needs) it makes any difference.

OK thank you all for the feedback.

Regards,

 

IanT

 

[IanTParticipant @iant]

A short update…

After some ‘umming & erring’ I finally decided to go the TouchDRO route. To keep the cost down I purchased the DIY “Kit” which has just arrived from the US. Thus far I’ve only opened the box and had a quick check. I’m somewhat tied up with other things at the moment so may not have time to put it all together for a week or two.

For the scales, I’ve ordered optical scales from Aikron DRO in China. Having advised others that the TouchDRO website was a very good source of information on all things DRO, it made sense to be guided by that advice. Yuriy states that if you have the room to mount them, optical scales work well for Mill X/Y axis. He also name-checked Aikron as being a reputable supplier. I selected the Aikron AKM series linear encoders with 5μm resolution and 5V RS422 output signals. I chose the RS422 O/P because this option didn’t increase the cost and Yuriy mentioned that they might be better when “noisy” brushless motors were involved.

The cost of TouchDRO & X/Y Scales (without Android Tablet) has been about £270 inc shipping (which was $80 of the total). This route will involve more effort in terms of assembling the TouchDRO kit and making mountings for the scales. I already know the ‘Kit’ version doesn’t support ‘probes’ or reference tracks (which the Aikron Scales have) but what I haven’t been able to determine is whether it can ‘sum’ the Z axis inputs if I decide to add this later. If it can (the fully assembled units can do so) then that will be a big plus for the T-DRO option.

I’ve just had a note from FedEx and the scales are leaving HK tonight and will be here in about a week. So we will see how things go but I think this combination should suit my needs well.

Thanks for all the input again.

Regards,

 

IanT

[Author]

Posts