After buying a DRO unit to replace one that came originally with my lathe some 5 years ago I had some issues getting it to work.

First of all I was buying one from Singapore that advertised it as “Suitable for replacing your faulty scale / using other brand of linear scale/encoder feedback.”

I must admit I was more than a little skeptical but checking their feedback reassured me that they seemed a genuine company. Also the cost, even including shipping from Singapore to the UK for a total of approximately £120 ($200) was £60 cheaper than the original supplier (China) quoted. I decided to go for the cheaper option (twas every thus!).

Whether the aggravation was worth it then I suppose it depends on where you are in the process... When pulling my hair out over the last few days trying to get it to work, then I cursed myself for being a cheapskate (or poor....). Now that it is finally working, I have a bargain!

The positives and negatives of the project from my perspective.

Communications:

Both negative and positive! Peter, the chap I was emailing, always answered emails promptly. However language proved difficult for me even though we kept sending photo’s. If I followed what I thought (not necessarily what Peter meant!) it wouldn’t work. Resulting in several photo’s/diagrams being emailed between us. One major issue revolved around the numbering of pins on the D plug. I was reading the numbers relating to pins to be soldered to the pins to be soldered!!!! No, the pin numbering relates to the front of the plug! Indeed the numbers could be seen when using a Jewelers loupe. I then constructed my own diagram and worked out the colours for each pin from Peters labeling of a photo I sent him showing existing wiring (this was the cause of the breakthrough really). One further fault/frustration was by reading that one pin needed to be soldered and then earthed (or so I think) and when trying the plug the numerals would only change up/down by one digit increase/decrease. In frustration I decided it looked like an earth fault (don’t ask me why!) and I thought &^%$$% it, I’ll cut this earth wire to that pin.

Low and behold, when connecting the plug up it worked!!!!! The second plug was then wired and I had two readings...joy oh what joy. Then I thought that knowing my luck there would be something wrong with the accuracy of each axis. So I set up a dial indicator and checked the readout movement against the dial indicators and all was well, phew! There was a slight difference but I wonder whether in fact this error is in the dial indicator or not...I suspect it is.

So if you do buy one of these DRO’s and you have the same make of scales (see picture) then the methodology highlighted below worked for me.

One major misunderstanding related to the numbering of 9 pin D-sub miniature plugs. The pin numbers relate to the front of the plug whilst you solder to the back! Now I consider that DAFT!

Using a jeweler loupe I saw the numbers on the front side of the plug, then transferred this to a diagram of my own identifying the pins from the rear and allocated the colours to that diagram. I then de-soldered all the wires, so having a clean starting point.

Solution

Remove all wires from D plug and identify the pin numbers (look at the front of the plug). Make your own diagram showing back solder part of pins

• Solder yellow wire to                 pin 9
• Solder Green wire to                  pin 8
• Solder Red  wire to                     pin 7
• Solder Blue wire to                     pin 6
• Solder Black wire to                   pin 2   (you can just leave this one in place if you wish since it doesn’t move)
• Solder back the Earth cable to the body of the plug

This results in a working solution that was not easily seen from Peters diagrams and photo’s but that may be as much to do with me not understanding enough, so I won’t lay all the blame on Peter. If you know more about electronics you may have had no problems!

I have added various photo’s of the steps I took to perhaps help.....If I had the above simple instructions from the start, no doubt it would have gone easily...To be fair to Peter he has asked for this solution so he can add it to his blog for assistance to others.

I have no complaints (now!) with the unit itself. It is far more substantial than the original Bica unit and I would suggest its more the top end of the market, so price seem very reasonable.

Would I do it again? You bet! Would I have done it again yesterday afternoon? No way! So what a difference 24 hours makes.

In summary the unit was certainly not plug ‘n’ play for my make of scales but Peter did help to get it working and that’s fair enough for me. I believe that Peter’s company will supply complete sets with scales and of course that would be a simple fit, and I have promised to fit a set to my refurbished Myford at some time.....but the purse is empty this year so it will have to wait

Its early days yet since I have just received the Dremel Speedclic cut off system today. However initial observations are favourable. It is an 'expensive' system on the face of it so I will need to see its overall durability, the efficiency of the cutting disc as well as how long they will last before coming up with a final rating.

I purchased my set with a pack of spare discs from Axminster tools and on inspection the quality of materials is very good, but no less than you should expect for its price. The true cost of Dremels cut off disc system will depend upon both the durability of the click mandrel as well as the life of the cutter so some time will need to pass.

On opening the package the mandrel seems strong enough and of course I tried to fit one disc without reading the brief illustrated instruction sheet that accompanied the package. It soon became obvious that you don't put the disc on and press it down whilst turning in one direction so I am ashamed to say I had a look at the destruction's. You simply pull down on the top mandrel collar and place the disc inside before giving it a twist (making sure the Dremel painted side is facing away from the mandrel and tool), then release the collar and your done.

I always run any new disc up to speed for a short time, no matter what its size. More than likely this is not needed but its something drummed into me at an earlier age. When trying the disc on a 3mm bolt it proved both quick and accurate. I like the large size of the disc but on some small work it may prove to big. My answer will be to run one or two disc down to a small size then replace with new and keeping these smaller diameters for other occasions.

One major advantage obvious even this early on is the changing methodology. No more loosing very small screws!

On the face of it the expense is worth it, but I reserve judgement until I know how long the disc will last.

Dremel Instructions and Speedclic