I am looking at putting a dro on a centre lathe.As you all know,one of the problems with these on a lathe is keeping the cables from getting tangled up in turnings as the sensor is moving with the slides,apart from the issues of mounting the cross slide one so that it is not in the way.With this in mind I was considering one of these wire rope versions from BW.It would mean the Z sensor could be at the end of the bed with the rope running along under the rack,nicely out of the way.The X could be mounted at the rear of the slide with the rope under the slide covers or inside the casting next to the screw.In both cases the cable could be clipped out of the way and should last a few years. The accuracy of these does not appear to be brilliant but for the few things that need better than 0.003" I could use a mike. Has anyone used these?Are they any good?Are they as accurate as advertised?Has anyone any better ideas? regards,Mark.
Hi Mark, I've fitted one to my 6" lathe (12" swing). I fitted one sensor under the rear of the saddle with the rope secured near the headstock behind the rear way, and another sensor on a bracket attached to the tailstock side of the cross slide, projecting rearwards, with the rope secured on the cross slide. The Z axis one, by virtue of its position, is totally invisible and protected from swarf etc. The X axis one is quite visible but, because its on the right-hand side of the cross slide, is pretty well protected. Its been installed for about 4 years now and hasn't caused any problems. I also fitted a 3rd axis sensor to my vertical slide. As you said, the accuracy is not great but it is definitely acceptable; I certainly wouldn't want to give it up. Email me if you'd like to see photos, but notice the anti-spam munging.
I have 3 axis fitted to my Bridgeport for quite a few years now. OK they are the poor man's DRO but the accuracy and repeatability have been very acceptable for my needs.
I bought a Newell Spherosyn system for my lathe, and the price included fitting. Mr fitting man asked to use the Bridgeport to co-ordinate drill some brackets, and was very sceptical about the BW Electronics DRO. However then he had the guts to eat his words when he found it was actually pretty well spot on !
I fitted a BW Electronics 2-axis DRO to my Myford about three years ago. It was affordable, easy to fit, it hasn't given any trouble and it certainly meets the accuracy and repeatability requirements of my day-to-day modeling activities. I was so impressed, I bought a second set for the mill, although the system is designed to 'clip on' and BW suggest a set can be switched between machines, including between lathe and mill.
I've run the Y axis cable, already inside its own telescopic sheath, along the headstock side of the cross-slide, where it's easy to fit a bit of ali angle as an additional environmental cover. The X axis runs along the rear of the bed, with a similar ali cover. I don't think I even had to drill a single mounting hole, using the ends of the cross-slide slots or existing tapped holes as appropriate.
The auxiliary functions, such as the ability to switch the display instantly between imperial and metric, accurately find a half way point, local and global points of origin of dimensions and a couple of others I forget, make me a very satisfied customer who would never want to go back to counting turns of a handle -- especially while trying to listen to 'I'm Sorry I Haven't a Clue!
Personally, I'm completely satisfied with my choice. --
Chris Edwards (in deepest Dorset) "....there *must* be an easier way!"
I'd wondered about the BW kit for my CVA lathe, they're not the simplest of lathes to put ordinary scales on & the BW would have been much easier. I was a bit put off by the fact that when I last looked at his site I couldn't find any statement as to their accuracy. After all the enthusiasm shown here, I'm wondering whether I made the right choice In the end I plumped for el cheapo far eastern conventional glass scales, Sino brand bought at the Harrogate show with a decent 'show discount'. I've just finished getting them set up & working, but haven't used them in anger yet. I've not found any reason to fault them yet, except maybe that the supplied fixing screws are a bit on the skimpy side. I'm going to have to modify my travelling steady, this straddles the cross slide and bolts to either side of the carriage but there's now a scale on one side. The BW system might have allowed me to avoid this.
Cheers Tim
Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service
Tim,I plan to fit them to a DSG 13T but also thinking about looking at fitting them to my CVA.Not the same need on the CVA as I find the dials very accurate.The CVA`s one of the very few machines that I actually enjoy using these days.If only it was 6" higher. regards,Mark.
You just reminded me -- I have the remove Y scale to fit the traveling steady! However, it's not a daily need and takes no more than five minutes to refit.
The only thing the BW kit doesn't like is being allowed to retract very quickly, when the very fine wire operating cable has a tendency to tangle on its spring-loaded reel -- not problem in normal daily use but to be remembered when fitting and removing -- don't ask! --
Chris Edwards (in deepest Dorset) "....there *must* be an easier way!"
BT are really excelling themselves. We reported an intermittent fault nearly 3 weeks ago. The phone works, usually, but often with crackling, so the connection is usually too poor for broadband to work. First engineer to come out just plugged his set in, tried a 'quiet line test' a few times, got one short burst of crackling & then peace. Went away saying 'phone us again when it's actually doing it'. Not easy when they make you jump through all sorts of automated hoops before you can actually speak to a human. By that time, the crackling has probably gone away!
10 minutes after he'd gone, I took him at his word & rang again. Next engineer said cheerfully that they wouldn't mess about, but would replace 200m or so of line where it runs through some trees. Slight problem, the inspection on the poles wasn't up to date, have to get a surveyor out to check the poles. One pole in neighbour's garden to be replaced, no machine access so tree surgeons & scaffolders needed. We were given a final date for completion of the repair, yesterday. Tuesday they put the new pole up (cut the line completely for 4 hours without warning us!), I asked the guys doing the job if they were putting up the new cable, not their job. Exected engineers yesterday to put up new line, no sign by 3pm so I rang 'fault management team' "The job's been signed off. Complete. Done." "But nothing's been done to actually repair the line!" "The job's been signed off. Done" "But....*****!!"!"
They now have to start a NEW job from scratch, can't reopen the old one. Promised an engineer for 'First thing' this morning. It's now
12:15, I've given them a bit of leeway & now it's time to have another go!
Sorry, rant over.
PS no it isn't, we got a bill yesterday for £55 'call out charge' for the first plonker who came out. He must have recorded it as 'no fault found'.
Cheers Tim
Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service
We had exactly the same problem a month ago. BT engineer came out & diagnosed it as the *long* phone extension line that ran outside the house for the SKY digibox. Unplugged the SKY line and the fault went away, and he was even nice enough to put it down as a fault on the BT line so we wouldn't have to pay call-out .
A pair of BT engineers have just left after about 3 hours here. Started with a test with a fancy box (BT Hawk) which shows some sort of 'echos' along the line, with readings of distance. He got a brief spike at about 150m, which subsided but there was still a small blip. Decided to do what the other guy had planned, & renew the line back to the new pole. Having got it down, they found a spot which was chafed halfway through, and the conductors actually broke when the pulled it out. Hopefully all will be well now, but what an exasperating business getting it sorted!
Back on topic, I'll get some pics sorted soon.
Cheers Tim Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service
Neat trick. Known as a "time domain reflectometer". You stick an electrical pulse on the line and measure how long it takes to reflect back to you. Discontinuities in the impedance of the line (such as breaks, shorts, crap connections...etc.) show up as reflections, and the time tells you how far from the test point to the discontinuity.
The long scale is screwed to a length of6mm flat bar which in turn is screwed into the rear of the bed casting. I do have a cover for the long scale, it needs the height reducing slightly before I can fit it. The adapter brackets connecting the long scale read head to the carriage are adapted from those supplied with the kit.
The cross slide scale is a smaller (& more expensive) format with a matching cover/backing plate which I've screwed directly into the cross slide. The read head is screwed into a piece of 8mm plate which was ground to give the right thickness to space it away from the carriage, drilled & tapped to the same spot where the steady should bolt.
formatting link
shows the travelling steady (follow rest), this straddles the centre of the carriage. I reckon I can cut the flange off the tailstock side of it, & weld/braze on an extension which bolts to the rear part of the carriage. The purists may be alarmed, what the hell if it works Cheers Tim
Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service
I had a fault on my phone very recently, crackling etc, three engineers visited and last one found problem which was cable from house to pole through tree's. Because automated system checks your line and finds no fault as soon as you request a human its £55.00. They are supposed to tell you this when you request engineer, my wife argued that we had not been told so charges were waived. Remember its £55.00 everytime you request an engineer.
Surely only if they don't find a fault on their equipment, otherwise it would be quite unreasonable.
The girl in the call centre, when I first reported the fault, set out in some detail how the engineer would check 'all the joints in the line from the exchange' (utter bo**ocks!) and then if he found the fault was in *our* equipment there would be a charge (fair enough).
When I rang the billing department to query the charge, they came up with "You requested an engineer". I *didn't* request an engineer, I reported a fault and asked them to fix it. They agreed to 'look in to the matter' and not debit my account until the matter was settled.
The member of the 'Fault management team' who was dealing with my case agreed straight away that the charge shouldn't have been applied. The billing department are probably under instruction to be fairly agressive in applying the charge whenever they can, but the concept of charging the customer for finding & fixing faults in the BT equipment is surely not on?
Incidentally the said 'fault management team' don't stand much chance of managing faults, they spent a couple of hours trying and failing to get hold of the engineering depot for this area, to find out why they hadn't come out as promised!
Cheers Tim Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service
The automated system that you listen to when you ring 0800800151 does a line check, if this says there is no fault then their equipment is deemed ok hence the callout charge.
Remember its £55.00 everytime you request an engineer.
Well it's £55 if the fault is in your house after the master socket. The man who you call out comes from BT Wholesale but your telephone contract may be with BT Retail, BT Broadband, Tiscali or someone else. BT Wholesale maintains the wires up to your master socket only. If you call them out and they diagnose a dodgy bit of extension wiring then you have to pay up.
Remember that windfall you may have got from buying and selling BT shares years ago? This is payback time. BT Wholesale is still a monopoly.
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