Here is a list of all the postings MW has made in our forums. Click on a thread name to jump to the thread.
Thread: Is it ok the hold a small lathe chuck in a larger one |
07/04/2017 10:44:59 |
I would admit to having used the 2" sherline chucks in the outside jaws of a 5" 3 jaw chuck, and to be honest I expected to see a runout error of some sort but didn't notice anything unusual, it appeared to turn true by eye atleast. It's very handy to use for very small work pieces where the bigger chuck would crush the material. You just have to be careful not to damage the chuck you are holding.
Michael W Edited By Michael-w on 07/04/2017 10:58:21 |
Thread: What Did You Do Today (2017) |
06/04/2017 20:04:14 |
Posted by clogs on 06/04/2017 19:32:23:
ED, at least it's post free !!!!!!!!!!!!!!!! Clogs I think that would be the cost of a solid gold tap follower. |
Thread: Machining a Washer - Procedure |
04/04/2017 23:03:25 |
Now all you have to do is make the nut and bolt and youll have the full set Edited By Michael-w on 04/04/2017 23:03:50 |
Thread: Drill Press |
04/04/2017 21:41:09 |
Posted by Neil Wyatt on 04/04/2017 15:12:20:
It's possible to split the base of the casting and fit a screw to nip it up. This has worked for some people. My Clarke CDP302B from Machine Mart is slop free and the table is very robust (no droop!) but it takes up a lot of space at nearly a metre tall and 410mm front to back. A lot more rigid than the budget Clarke one which nonetheless I used happily for over sixteen years! Neil
For the stick they get on this forum, Clarke do pretty robust things at low prices, there's no way I could afford to splash 1k on a bandsaw for eg.. If this was years ago I'd have no choice but to hacksaw it. Michael W |
Thread: ER40 Collet run out. |
04/04/2017 21:38:42 |
Posted by Nick_G on 04/04/2017 20:58:17:
. My advice would be to send both the chuck and collets back. - I initially purchased not knowing any better quite a bit from that company. - Everything (except for a vertex milling vice) has had to be replaced or needs to be. Then purchase a chuck and collets from somewhere that does quality control to a reasonable standard themselves and does not rely upon the end user (the customer) to do it for them. I have an ER collet chuck for my lathe purchased from ARC and it is a excellent bit of kit by any standards. Especially for the money. Nick it may be too late for that. I don't think they'd refund it. Michael W |
04/04/2017 18:07:42 |
If it makes you feel any better i have the same problem with a morse taper collet chuck from rdg again. The front of my spindle taper registers zero runout on the bore too. I get around .15 runout. From the collet chuck withva bar held in. Whereas my 3 jaw does the same with 0.02-0.05. I was going to use a flange mounted er chuck with a backplate to see if this would correct it. But seeing this makes me feel uncertain. It would work. Maybe skimming the chuck taper insitu would help? |
Thread: Machining a Washer - Procedure |
04/04/2017 07:14:02 |
IPosted by John Stevenson on 04/04/2017 00:17:12:
Posted by Michael-w on 03/04/2017 17:43:33:
I'd go for trepanning, less waste involved and can use the corners for bits and pieces. The only thing you have to be careful of when trepanning large diameters is one can get a bit carried away with the speed and burn the tool. Michael W Edited By Michael-w on 03/04/2017 17:45:01 Why go to the trouble of trepanning the corners ?
You will have 4 interrupted cuts every rev getting an 80mm circle out of an 80mm square plate and just to save 4 tiny triangular bits of steel that will never get used again ?
So for saving 4 silly corner chances are you break a trepanning tool or rip it out of the chuck and you have to start again.
I've looked at the size again and realized you can't do it without an interrupted cut simply due to the size of the plate, in this case you're better off hacking the edges off and turning the o.d with a turning tool. Michael W |
Thread: Magnetic metal lids |
03/04/2017 17:55:31 |
Well given the large amount of iron that make up steels, it stands to reason that it would maintain some magnetic property even after the inclusion of non-ferrous elements. Michael W |
Thread: Machining a Washer - Procedure |
03/04/2017 17:43:33 |
I'd go for trepanning, less waste involved and can use the corners for bits and pieces. The only thing you have to be careful of when trepanning large diameters is one can get a bit carried away with the speed and burn the tool. Michael W Edited By Michael-w on 03/04/2017 17:45:01 |
Thread: New pound coin |
03/04/2017 17:41:51 |
Posted by Martin Kyte on 03/04/2017 16:17:41:
Maybe not so odd? Is not a pound called a pound because it was a pound weight of silver?
I think you've got it right, the original pound was; eventually the coin makers started to introduce lead and tin into the silver and it devalued the currency to such an extent in the medieval ages, that they were summoned to Winchester and some 60-90 men were severely punished. |
Thread: Motor connection |
02/04/2017 18:36:02 |
Ok, there has been a lot of responses to this, in one case i'm glad but in another sense, my apologies to the OP for diverting the topic of conversation to this, I just didn't think it would generate this much talk at the time. I'm thankful to all the sensible posters who have come up with what needs to be considered with regards to the inverter, I feel i'm left with a couple of options. 1. Provide an emergency stop directly to the source of the power, namedly an emergency "type" stop to bridge the single phase live wire from the wall socket to the inverter, providing it does what is intended, it shall provide an almost guaranteed cut-off of power, that much we can be sure of, However, what is not certain, is if the inverter will actually shut off instantly, it actually takes 3-4 seconds to respond to the wall socket being switched off, this would not suffice as an emergency stop if that is the case. 2. Use either the existing connections between GND/24V on the controls, OR to use the free ports to program/remap a new function that interrupts the motor with no coasting time, I have used this inverter control before to setup new frequency from 50hz to 60hz parameters so I am fairly familiar with the jargon and how it's laid out. I am aware that if I am successful it may not come under the technical definition of an "emergency" stop, but i'm not perfect, the worlds not perfect, and no matter how stupid anyone thinks I am, I did at least try to pre-empt some kind of risk here, as well as an opportunity to learn more about the system, this might lead me to knowing how to rig some L.E.D's in parallel to the system to have functioning lights. For the ambiguity that I still have in my mind with regards to what route I shall take, I have made sure that the red button twist switch I have chosen, will be able to sustain a thermal current load (I-th) of 10A and 660V, well within the remit of a 7A maximum 2.2KW inverter. I can't really do much until then but I will trawl through the manual to see what I can gather as to whether a programmable function is doable. Thankyou, Michael W Edited By Michael-w on 02/04/2017 18:37:04 |
02/04/2017 14:47:50 |
Posted by Harry Wilkes on 02/04/2017 14:32:42:
Posted by Brian Oldford on 01/04/2017 17:29:21:
Posted by Michael-w on 31/03/2017 19:48:01:
Ok i'll see what i can do Les, however, i don't think i ever got a circuitry diagram nor can i find one online however, i can open the thing up and see if i can make sense of the spaghetti inside, this is the best thing i could find on "what does what" for the pendant in relation to the inverter.
Is that wiring real? Or is that amount of exposed conductor an April fool? I realise control signals are low voltage but it look 'orrible and is an invite to future problems.
Edited By Brian Oldford on 01/04/2017 17:29:48 Brian was just thinking the same thought ref messy wiring also personally I do not like soldered ends after many years of fault finding I wouldn't mind a £1 for every bad connection I've found due to soldered or crimp terminations on low volt control wiring. H
Before! we drift into the world of pendantry may I remind you this isn't my image, this is transwave converters or power capacitors' image, not mine, yes mine are similar to this, no, nothing has gone wrong because of it. They manufacture these units commercially, and have done so for a very long time, if they can't competently do it, then maybe you should tell them, because it isn't bothering me or my inverter(s). In fact, I don't think any of those connections are clamped in the holder, they are simply presenting them to show you where they go. Michael W Edited By Michael-w on 02/04/2017 14:53:40 |
01/04/2017 14:05:53 |
Posted by Les Jones 1 on 01/04/2017 12:20:04:
Hi Mitchael-w, Les. Thanks les, you have pointed me on the right track at least, i'm sure I could try making a diagram of it but maybe I already know now which two connections(brown/white) concern the running of the motor, and logically placing a normally closed switch between it would provide a means of interrupting it. I'm going to stake a bet on that a switch between +24V and the fwd/rvs switch would do exactly that, it isn't a large burden to repair the connection should it prove unsuccessful and the GND could be tried. The relay has complicated the situation by scrambling the connections between the START, STOP and jog/run toggle switch, I believe this is because when you switch from running to jog mode the pendant is designed to change how the stop function works. In fact the only thing with straightforward connections is the rheostat! I'm definitely in agreement that the most straight forward option would be between the live wire of the input and the inverter, which would mean the inverter would switch off. However, we would probably need more than a garden variety emergency stop(like a heavy duty, metal clad switch) to handle a large current passing through it and the housing/switch construction would also need to be ground. Michael W
Edited By Michael-w on 01/04/2017 14:11:29 |
Thread: soldering stainless steel to copper |
31/03/2017 23:00:30 |
Posted by Nick_G on 31/03/2017 22:47:37:
Posted by Michael-w on 31/03/2017 15:51:16:
Ah I see, you learn something new everyday, Michael W . Where id the photo of that boiler you 'constructed' Michael. ............ That was an educational masterpiece for anyone wishing to know anything about soldering.
Nick Cheers, it's good to know you haven't forgotten me yet Michael W |
Thread: Motor connection |
31/03/2017 22:48:26 |
So Blue, Yellow, Green (10V, AI, GND) All go to the potentiometer which is obscured by the main cable, White and Grey (S1, S2) are the toggle Switch for FWD/RVS. A third common cable connects this to the stop switch Pink (GND) connect to terminal on the STOP switch. This is where it gets messy. Brown (24+) goes to one side of the JOG/RUN, however the second terminal for the toggle has a relay, this connects to both start and stop, through white wires, one going to stop and two white ones going to both terminals for the START switch. Michael W |
31/03/2017 22:37:45 |
And just for good measure i'll show the inverter view again so you don't have to keep going back to look at what it connects to... |
31/03/2017 22:36:38 |
Okay, This is the machine.. This is the pendant front view.. Here is the Inside of the pendant.. |
31/03/2017 22:26:06 |
Posted by Les Jones 1 on 31/03/2017 22:01:27:
Hi Mitchael-w, John makes a good point about having the emergency stop in conjunction with an NVR in the AC supply to the VFD I think which way you choose to do it is personal preference. It is normally not recommended to remove the power from a VFD when it is driving the motor but safety is more important than the risk of damaging the VFD. I have chosen to tell the VFD to stop the motor. The reasoning is this. I think the risk of a fault occurring on the VFD that prevents it stopping the motor at the same time as you have an accident is very small Also the VFD stops the motor quicker than it just coasting to a stop. You can get some emergency stop buttons that latch in the off position. You could use one of these without an NVR providing the contact rating was good enough. Les. I will show you all a picture shortly as I dismantled the pendant so I could show you, it has toggle switches for FWD/RVS and JOG/RUN, the start and stop switches are buttons and theres a vario for speed. The inverter can reduce it's coasting for start/stop to literally nothing so it just goes dead as soon as you hit stop, (although this can send a backwards current through the inverter due to the fact the machine will still be spinning after the power is dead) The manufacturer recommends that you use a mechanical break, as it does not have the capacity to do that electronically on this model. Michael W Edited By Michael-w on 31/03/2017 22:26:49 |
31/03/2017 22:18:53 |
Posted by Journeyman on 31/03/2017 22:03:41:
The image above shows stranded cables that have been tinned before being clamped in the connector block. I believe that this is no longer considered good practice. The cables may be tinned at the very tip only to maintain shape but no further. Apparently the solder wicks along the cable under the insulation and may lead to cracking especially if vibration is present. The length of bare wire is also too great, any flexing may lead to a short. Crimp ferrules on the cable ends are now I believe the preferred method. John I would agree, I've definitely heard people talking about using crimps or connector blocks for AC power, although those wires in particular are simply part of the wiring for the pendant and therefore have no direct connection to the power line, i'm not sure i've heard anything about vibration before but this is a stock photo from transwave converters, and that's the way they supply it. Michael W |
31/03/2017 22:14:25 |
Posted by John Rudd on 31/03/2017 21:52:14:
Posted by Michael-w on 31/03/2017 21:41:44:
it isn't exactly software but more like an electronic input rather than a raw electrical one..... Michael W
The control terminals of an inverter are the external interface that is controlled by software....thats my point... Remove the power, the inverter/motor is dead.... Believe me, I wish it was as easy as that sounds. Michael W |
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