I have them sorted (albeit not wired) for X but I'm still working on the best placement for Y and Z.
- Thread starter Fastdruid
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I have them sorted (albeit not wired) for X but I'm still working on the best placement for Y and Z.
After a bit of a think I've gone with a 12-24V 9W (900 Lumen) LED bulb which is a standard fit in the B22 and I'll stick a small 240-24v transformer in the original switch box.
Bit of a (minor) set back. I wasn't happy with the backlash on the Y axis. There was best part of a half tooth worth of "play" and it was noticeable that the ballscrew itself was moving in and out.
On taking the bearing block apart it became unpleasantly clear just _why_ I had some play.
A 6001 is a plain "deep groove" rather than a pair of opposed angular contact bearings (7001) which is what it should have been.
I've ordered a pair of 7001's and thankfully the 7001 is identical dimensionally to the 6001 so there shouldn't be any issue there.
On taking the bearing block apart it became unpleasantly clear just _why_ I had some play.
A 6001 is a plain "deep groove" rather than a pair of opposed angular contact bearings (7001) which is what it should have been.
I've ordered a pair of 7001's and thankfully the 7001 is identical dimensionally to the 6001 so there shouldn't be any issue there.
Mark Davison
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Did you buy it direct from China i assume?
I have almost 0.1mm of play in my Y axis and it isnt end float in the screw. I need to strip it apart to see what is going on.
Turns out my 10 way oil distribution block/valve requires some fettling as well. The valves on 4 of them don't work (won't close). On dismantling it became obvious why. The needle valves (not a great description given the blunt (and somewhat random shapes) dont line up withe the seats. I'm part way through redrilling and sleeving the seats. I'm also turning a sharper point on the 10 adjusters, for which I had to make a fixture to hold them. The joys of chinese quality control.
I have almost 0.1mm of play in my Y axis and it isnt end float in the screw. I need to strip it apart to see what is going on.
Turns out my 10 way oil distribution block/valve requires some fettling as well. The valves on 4 of them don't work (won't close). On dismantling it became obvious why. The needle valves (not a great description given the blunt (and somewhat random shapes) dont line up withe the seats. I'm part way through redrilling and sleeving the seats. I'm also turning a sharper point on the 10 adjusters, for which I had to make a fixture to hold them. The joys of chinese quality control.
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Unfortunately, yes. I did think about making my own but wanted to save the extra machining and UK sourced is 3x the price.
It's less quality control here and more blatant substitution of cheaper parts, a 6001 at retail is maybe £3, a 7001 is about £9. So whoever is making them saves maybe £6 (on the basis of wholesale prices) and of course that is extra profit.
Not like they're _actually_ cheap either.
Of course I bought it 7 months ago so well past any chance of refund.
Mark Davison
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Unfortunately, yes. I did think about making my own but wanted to save the extra machining and UK sourced is 3x the price.
It's less quality control here and more blatant substitution of cheaper parts, a 6001 at retail is maybe £3, a 7001 is about £9. So whoever is making them saves maybe £6 (on the basis of wholesale prices) and of course that is extra profit.
Not like they're _actually_ cheap either.
Of course I bought it 7 months ago so well past any chance of refund.
Bearings turned up, as did the belt.
Pressed out the original bearings and replaced them. Now have a tiny fraction of a degree of play rather than a whole tooth!
Fitted the limit stops to the X and tested them. Set it for now to about 3mm before it physically hits. Haven't tried it with the controller yet, just powering them, hand winding the axis and using the LED on the back to see when they trigger.
Had a good think about how to run the Z and Y.
Think I'm going to run the top Z as a clamp onto the ways (I'll 3D print that), that lets me move it for those really strange edge cases (eg machining something using the horizontal spindle), the lower one I'll have trigger off the base.
On the Y I'm going to have the front attached to the bracket for the bearing and the rear on one side. That's going to be the most awkward one I think.
Finally thought about the wiring for X. After some consideration I figured not worth trying anything really funky, I'm going to run it the same way the original feed motor was to the column.
Pressed out the original bearings and replaced them. Now have a tiny fraction of a degree of play rather than a whole tooth!
Fitted the limit stops to the X and tested them. Set it for now to about 3mm before it physically hits. Haven't tried it with the controller yet, just powering them, hand winding the axis and using the LED on the back to see when they trigger.
Had a good think about how to run the Z and Y.
Think I'm going to run the top Z as a clamp onto the ways (I'll 3D print that), that lets me move it for those really strange edge cases (eg machining something using the horizontal spindle), the lower one I'll have trigger off the base.
On the Y I'm going to have the front attached to the bracket for the bearing and the rear on one side. That's going to be the most awkward one I think.
Finally thought about the wiring for X. After some consideration I figured not worth trying anything really funky, I'm going to run it the same way the original feed motor was to the column.
Mark Davison
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I have linear scales mounted on mine so I have mounted the limit switch to those. The switch are on the bracket that carries the read head and the stops are screwed to aluminium flat bar mounted to the scale.
Carl Wilson
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There are a lot of things on these machines that I look at and wonder "why did they do it like that?".
It's a genuine mix of beautiful precision and half arsed bodgery.
Like the Lo-Vo Lite that is mounted on three screws that are drilled through into the gearbox so if you remove it then it leaks oil through them.
Or the wonky drilled holes in the control box.
Or the front control panel that turned out to be a trapezoid and fitting a rectangular panel means it looks "off".
A refund on £3?Unfortunately, yes. I did think about making my own but wanted to save the extra machining and UK sourced is 3x the price.
It's less quality control here and more blatant substitution of cheaper parts, a 6001 at retail is maybe £3, a 7001 is about £9. So whoever is making them saves maybe £6 (on the basis of wholesale prices) and of course that is extra profit.
Not like they're _actually_ cheap either.
Of course I bought it 7 months ago so well past any chance of refund.
No a refund/return on the whole thing (it was £20) It's not what was sold which was a double angular contact bearing block. I know some people get hung up on ultra-precision bearings but for what this is I don't think it justifies them (in the same way it doesn't need ultra precision ballscrews) so it should have been fine *if* they'd been the correct type.
Of course the only way to tell with such things is once you have it in your hand and inspect it.
Equally it could have not been at all "malicious", just someone who didn't know that the type was important and just went for the cheaper ones.
Carl Wilson
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My Harrison M250 lathe is the same. Wonderful workmanship and attention to detail but in the odd place it looks like they were doing it blindfolded. With both arms tied behind their back. And both legs.
Slow progress due to many other things on the go.
Anyway, have the light now re-fitted and working.
Wired so the original transformer is bypassed by linking the primary to secondary fuses instead of them being wired to primary and secondaries on the transformer.
This lets it uses the original switch.
In theory as it's just a normal B22 bayonet fitting could use a 240v bulb...but for safety instead using a 9W 24v LED bulb running off DC (one of these https://www.ebay.co.uk/itm/172880725920 )
Although I already have 24v for the "control" wiring I decided I wanted it to be separate. So there is a little 240v AC->24v DC transformer wired up. I wanted this originally to live in the switch box but it didn't fit so instead it sits in the base.
I used the original wiring blocks to do it, wiring is 1.5mm^2, all overkill for 9w @ 24v but does mean if I decide to use 240v for whatever reason I can.
Anyway, have the light now re-fitted and working.
Wired so the original transformer is bypassed by linking the primary to secondary fuses instead of them being wired to primary and secondaries on the transformer.
This lets it uses the original switch.
In theory as it's just a normal B22 bayonet fitting could use a 240v bulb...but for safety instead using a 9W 24v LED bulb running off DC (one of these https://www.ebay.co.uk/itm/172880725920 )
Although I already have 24v for the "control" wiring I decided I wanted it to be separate. So there is a little 240v AC->24v DC transformer wired up. I wanted this originally to live in the switch box but it didn't fit so instead it sits in the base.
I used the original wiring blocks to do it, wiring is 1.5mm^2, all overkill for 9w @ 24v but does mean if I decide to use 240v for whatever reason I can.
Carl Wilson
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I am definitely going to copy that idea on mine.
Fitted a way cover to the front of the Y axis.
I'd got particularly fed up of cleaning the bits where they sat on the knee and would get both crushed between the Y and the mounting block for the Y screw as well as running the risk of getting swarf stuck between the ways and the sliding surface which would then score it (and you can see a little where that has happened in the past).
This is the cover fully "stretched" with the Y right the way back to the column.
And this is it with Y fully forwards.
The way the rubber has been clamped has been carefully done to ensure that it will default to pop "up" and out of the gap rather than risk being trapped. I'm sure that there will be a substantial accumulation of swarf on the top of it but that shouldn't affect anything.
And from underneath.
I'd got particularly fed up of cleaning the bits where they sat on the knee and would get both crushed between the Y and the mounting block for the Y screw as well as running the risk of getting swarf stuck between the ways and the sliding surface which would then score it (and you can see a little where that has happened in the past).
This is the cover fully "stretched" with the Y right the way back to the column.
And this is it with Y fully forwards.
The way the rubber has been clamped has been carefully done to ensure that it will default to pop "up" and out of the gap rather than risk being trapped. I'm sure that there will be a substantial accumulation of swarf on the top of it but that shouldn't affect anything.
And from underneath.
Not much progress, partly because I've been busy and partly because the garage is cold and I've been too lazy to get out there.
...but also because I have been making the most complicated way cover for the Y and Z possible. This took me hours and involved lots of welding, many very complicated parts and is just massive overkill.
It is now however finished so I can finally reveal it! Sprung at the top with a roller at the bottom so it stays out of the way.
Not 100% sure on the "rubber" sheet I've used, may have to find an alternative and replace it. It appears to have swelled up where oil has got on it. Might be fine but just swollen, we'll see.
Next up...wiring. Lots and lots of wiring.
...but also because I have been making the most complicated way cover for the Y and Z possible. This took me hours and involved lots of welding, many very complicated parts and is just massive overkill.
It is now however finished so I can finally reveal it! Sprung at the top with a roller at the bottom so it stays out of the way.
Not 100% sure on the "rubber" sheet I've used, may have to find an alternative and replace it. It appears to have swelled up where oil has got on it. Might be fine but just swollen, we'll see.
Next up...wiring. Lots and lots of wiring.
Carl Wilson
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- Moray
That is a really clever idea. Check that the rubber sheet is not EPDM. Oil has EPDM for breakfast.
