Sieg SX1LP Milling machine

Yes and modifying a few of the brackets supplied with the scales. Nothing too onerous in hindsight but it did take some thinking about and inevitable backtracking at various points.

 

For my birthday last October I received a Digital ReadOut (DRO) kit for my Sieg SX1 LP mini mill. I fitted it over a weekend last October and although I took photos as I did each stage, I haven't yet got around to writing it up. Paul's posts (@OzzyO) on fitting a DRO to his mill prompted me to get my finger out so that anyone who is interested will get a couple of takes on fitting them to different types of mill.

As I am not anywhere in the same league as Paul when it comes to machining, my first port of call when looking was to YouTube. To see if anyone had done a video on fitting a DRO to a similar mini mill. I was quite surprised that at that time there wasn't any to be found (there may well be now as I haven't looked since).

Having realised that I was essentially on my own, my first port of call was to ring Arc Euro Trade whom I bought the mill from. To ask if they did a DRO kit for my mill. I was a little surprised that they didn't, as they seem to cater well with other accessories and tooling for the range of machines that they sell. Their recommendation was to talk to a company called Touch DRO who apparently do something suitable.

I have seen a few videos which featured Touch DRO units and confess that I was not keen on the idea. This is on the basis that they require the use of scales, which connect via Bluetooth to a tablet for the display. I spent 20 years in IT support and the last thing I want is yet another device.

Again on the basis of seeing a few videos on badged variants of the units supplied by Warco I opted to buy from them. I got a display reader, two x 100mm glass scales and one x 250mm.

The idea was that I would use one of the 100mm scales on the Y axis (front to back movement of the table for those unfamiliar with the axis terms) and the other for the Z axis which is the up and down movement of the mill head. This latter proved to be a mistake which I will elaborate upon later. The 250mm scale was to be used on the longer X axis table (which is what the LP designation of the model number refers to).

 

The Warco items duly arrived and each scale, came with a main rear mounting bracket and a pair of additional mounting brackets (Shown below) and a selection of M4 and M5 cap screws.





Main mounting bracket.





These are the additional brackets that were spare as I only ended up using one of each along with some sections of aluminium angle which I had rescued from a set of shelves that I had dismantled.


To ensure that the job wasn't stopped for lack of drill bits if I broke any, I put in and order to Drill Services Horley for a couple of 3.2mm and 4mm drill bits. Of course because I had them to hand I didn't break a single drill bit.


All the holes drilled in the mill itself were done using a battery hand drill and being cast iron it was quite easy going if a bit messy.


The main mounting bracket holds the glass scale and then the read head is mounted so that when either the read head or the scale moves it reads off the distances. In my installation I have the scales mounted to the moving table axis and the read head's fixed to the machine bed. On the Z axis this is reversed and the scale is fixed to the column of the machine and the read head moves up and down with the milling head.


I decided to start with the Y axis as being one of the shorter ones so easier to handle and definitely the easiest to access on the left side of the machine. However as soon as I took the 100mm scale out of the packaging I knew that I had made a mistake in getting a second 100mm scale for the Z axis although it would be fine if I was working with the vice or rotary table mounted on the bed it wouldn't allow the head to come down far enough to mill anything directly mounted to the T slots of the table.


I immediately contacted Warco and explained my error and asked that since I hadn't opened the second scale, would it be possible to return it, and swap it for a 200mm scale. They were happy to do so and would sort out any additional cost incurred once they had it back with them. I returned it to the address on the signature of the person who had sent the invoice. This proved to be a mistake as it turned out that they had moved from that address so the package was returned to me. I called them and advised that there would be a delay due to my sending it to the wrong address which was on their email.


I looked at the actual invoice and noted their new correct address and re sent it there. As good as their word they very quickly despatched the replacement and didn't charge me a penny which despite my frustration at them not having the correct address on their correspondence I did appreciate.

 

I mentioned that I started with the Y axis first








There was a convenient ledge on the side of the bed casting which allowed me to add a parallel to get the backing plate up to the right height to mark for drilling the mounting holes. The 123 block is just holding it in position.





I added some engineers blue and marked the holes with a scriber then punched the centre.





Drilled, tapped and cleaned up with IPA





The backing plate in place, so far so good.





A trial fit of the scale to work out where the reader needs to be fastened to.





At this point I realised that I would need some packing pieces behind the mounting plate to make it stand off due to the useful ledge that I referred to earlier and allow the reader a clear track without being forced to run at an angle and to allow the fitting of the chip shield which didn't quite fit when flush against the table.


I used a slitting saw to cut down some sheet material which some bar stock had been attached to to stop it being bent in the post. It's quite interesting material in that it is two layers of thin aluminium bonded either side of some plastic material. Being layered it's remarkably strong and light and I thought it too good to throw away so it went into my useful bits box.





You can just make out in this shot where I slotted the vertical mounting holes in the angle bracket, again to allow the reader to track without adding undue pressure. You can also see the packing strip between the mounting plate and the edge of the table.

 

The next step was working out where to position the reader to get the full length of travel from it. I measured how much space the X axis scale would take up when fitted, added a couple of millimetres for clearance and used that as my forward limit. I then marked the base and drilled and tapped the base.








This is the Y axis scale fitted with it's swarf cover and working.

 

The X axis was a bit more involved in that it was harder to get access to even with the mill unbolted from the bench.


First job I found that the slots in the mounting plate were a bit tight for the M5 screws so I opened the slots with the mill.






I also milled the second slot to have vertical as well as horizontal movement as it's important to have the scales both level horizontally and parallel to the travel of the table for the highest accuracy. As they come one slot is vertical and the other horizontal but being aluminium they are easy to modify with the mill.


After bluing up the rear face of the table I was lucky in that I had recently bought a couple basic C clamps to use for clamping one of my vices and my rivet press temporarily to the workbench when I need to. These fit quite nicely edge on in the T slot so I was able to clamp the mounting plate in position allowing me to move the table to either side of the column so that I could mark it up without removing the table at this stage.











Again, it was a bit of a squeeze but I was able to drill and tap the table without removing it.











The next task was working out how best to mount the reader but I will cover that in another post.

 

Hi Jim,

Like a lots of things in life, the doing, doesn't actually take that long. It's the working out what you need to do that takes the time (and energy!).

 

It wasn't always so Jim. If you have a watch of the recording of my An Evening with session I explain why on there. I will dig a link out to it when I have a minute.+

 

Hi Ken,

Yes, we are demoing there all weekend (3 days) I have election set up tonight, then polling station all day tomorrow, set up at Leeming Bar on Friday night then there for the next 3 days so a busy week all in all.

 

Here you go Jim.