Member postings for MW

Welcome Martin,

This is a great community to be a part of.

Michael W

You probably know from my regular musings that I have a Sherline Cnc lathe long bed and a universal cnc sherline mill, and I can't resist reading any posts about them.

I don't use them as much as I should do, because they are dead accurate, if I take the time to set it up, I can guarantee parts to within .01 mm shafts and external features, but on my bigger machines, (perhaps due to the way I treat them!) it's more like .05 and i'm happy with that mostly but it always amazes me to see their capabilities.

Quick note on the cnc rotary table, I have that too and it's built to a quality not seen on the other hobby indexers. 

You may notice that on the demonstrations the speed is always up to the top and with carbide tooling because it tends to struggle on lower speeds on high speed steel, it does have a compensation feature on it's board but it's not enough to overcome large cuts, cuts that I could get away with on my bigger lathe, like 4mm roughing stainless steel.

They could probably do with upping their game on the motor side, it's only 1/5hp but you can get a brushless 500W motor with an ER fitting head for about £100 with variable speed. (Not to act as the spindle but simply to hold the pulleys where the other motor would normally go)The other features of the sherline machines are nigh on flawless that being said.

The older Australian sherline machines are quite rare but they were actually equipped with a small induction motor with a single/double speed settings on the pulleys, and are probably better off sticking with them. C;early the original designer, now long gone I think, intended it to give decent power output for a small machine. 

The variable speed feature on the brushed standard motor gives the illusion of being able to handle larger diameters with less power, which is a nonsense to say that you could part off a 1" steel bar with 200rpm on the wee motor. Doesn't work. not unless you machined a different pulley set. 

I would also praise them on the amount of literature they offer to help people understand what to do, far beyond what other machine makers are willing to offer. 

Michael W

Edited By Michael-w on 28/04/2017 17:50:34

One development that seems to have gone amiss in our musings is that countries tend to sell their energy to other ones now, French power plants meet some of the U.K's demand if needed. Russia sells gas to other countries through a vast network of pipelines. Mexico also sells some power north to the U.S.

If i'm to take a punt at what might happen, since china is apparently erecting coal power plants like they're going out of fashion, is they might find they have far more energy than they're actually using, what to do, other than sell to others? We may end up buying Chinese power if they can find a way to export it..

Sadly though, politics will probably get in the way of it.

Michael W

It is sad to see coal disappear but I suspect the future will be largely nuclear, the energy generation is just extraordinary, this comparison of energy sources was in E.P.E magazine;

Lead acid battery; 0.17MJ/kg

Alkaline Battery; 0.5MJ/kg

Lith-Ion Battery; 0.875MJ/kg

Wood; 16MJ/kg

Petrol; 46MJ/kg

Hydrogen 142MJ/kg

Uranium in a breeder reactor; 80,000,000MJ/kg

Like others have said, to have the entirety of the countries ever growing guzzle of energy sufficiently met, something has to give and it can't be mile after mile of windfarms and solar panels. For the mean time, we can focus our efforts on how to make nuclear generation as safe as possible and, for the whole reason why Sellafield exists, what to do with all the spent rods. 

I agree with Duncan W's comment about electric oil heaters, woefully inefficient compared to gas. 

Michael W

Edited By Michael-w on 27/04/2017 18:18:12

Needs to be more like a v shape, just like I thought.

the edges look so rough i'd almost call it a rasp, how to wear out any mating components in no time at all.

The other thing is that the basis for the technology in metal powders is already used in industry, except they don't need to print it, they just sinter it if they're looking for volume production.

The problem is when it comes to all kinds of steels, they are made in furnaces that need to reach thousands of degrees, and then go through a further tempering process in order to make them to spec, this is what gives them their enduring, lovable qualities of metal. 

Even in plastics, the rate at which cnc sliding head lathes can rip through bar stock kills it's appeal for quick industrial turnarounds, injection moulding (theres an American company I saw once that makes tiny super accurate injection moulded parts which have amazing level of detail). is also much quicker for larger components.

I can see why some remain doubtful for it's ability to revolutionize, they should get over the hype and see that although it's exciting, it's also a complimentary method not a "junk your old machines and all go with this" type of scenario. 

It's a bit like when tubal cain said we should junk all our old imperial machines because nobody will want to make the sizes any more, and they're still here funnily enough, and not too keen to go anywhere any time soon.

Michael W

Edited By Michael-w on 26/04/2017 19:20:50

This could just be a case of the wire dia. being inappropriate for the size of the current going through it, it just needs a larger copper wire to dissipate the heat.

In my case i'd have no choice but to fix it myself.

Michael W

Edited By Michael-w on 25/04/2017 20:26:22

I'm probably more of a brute than a chemist which is why i mainly use a wire brush at high speed to clean up steel. Does a wonderful job on most stuff.

Michael W

Edited By Michael-w on 25/04/2017 15:39:58

I don't think i'd even know where to begin on pre-load, I haven't touched the headstock since I bought it. All I've seen from the utube vid is that it's a taper roller that sits inside a tapered ring, which is just force fitted into the housing.

I think you're probably right about the bearings too, but i reckon RS is pretty sound when it comes to their selection.

Michael W

Thanks for the suggestion, but there is no back gear on this one, just a gear box that runs below the headstock for switch between half speed, idle, full speed for the lead screw self cut pitches.

Although sound can be deceiving sometimes, i'm fairly confident this is a little bit of bearing noise, which doesn't seem to be affecting the performance of the machine for the moment so I'll leave it.

You can only notice it if you really listen and it may have been that way since I've had it and just simply didn't notice it before.

Michael W

I only realized after having trouble getting solder to shtick, that I was using the wrong flux, I read the CuP alloys guide and it set me right. If the flux burns off at a lower temperature than the brazing then it's pretty much useless.

I think my worst humiliation on here has to be the 1st rolled copper tube I made which i'm forever reminded of. ​

If you image trying to make a tube out of quality street wrappers, that was about the same sort of texture

Well theres nothing worse than being too proud for your own good so maybe it's better that it happened.

I now have an aversion to rolling tubes but rest assured I have since gone onto make a lot of very sound brazed joints. It has to be one of the best ways of joining mild steel without a lot of bother.

Michael W

Edited By Michael-w on 25/04/2017 15:26:40

I would hate to say it (as I do own one), but I think they make far too much to care, the advert on the magazine/web would be all the PR they need, they have been around for a longwhiles and probably make most of their gains from shows and word-of-mouth, hell maybe even a few colleges have warco's sitting in them.

That said, I have never had any reason to dislike them, their spares department have been far better to me than Clarke ever were, I think it's luck of the draw on who happens to take your order most of the time.

Michael W

Edited By Michael-w on 25/04/2017 01:35:04

Maybe try the boring head build in M.E.W? It was a good one if I remember rightly, and none of that fuss of having to measure taper thou per foot with morse tapers when you can be smugly satisfied cutting a whole 8 degree taper for the shank.

Michael W

Edited By Michael-w on 24/04/2017 21:31:28

But what about all the wonderful screening the shrub provided?

Clearly he was some kind of marketing genius as he is now able to sell the same machine as years ago for a tenfold increase.

Well I started to dismantle the headstock and this was as far as I got to where the rear taper roller starts, the front one is apparently just a "roller bearing"? according to the diagram.

The rear one seems to be the one clicking, it quietens down if I put a little grease on it. I watched a youtube vid of a guy doing exactly what Nick G, said, luckily the guy specifies the part from RS at £18.

Having said that, it would probably be wise for now to leave everything alone, but I've saved the link to the bearing I need just incase, it's only noticeable very quietly if it's idle and turned by hand, I am going along with S.O.D's wisdom here and, if it's not affecting anything i'm making, it's probably better to leave it for now.

I am glad though that I am atleast aware of what I need to do just incase, I think all that needs to come out after the pulleys is a front securing plate and the whole assembly can be knocked out with a wooden dolly.

Michael W

Yeah I definitely wouldn't be doing any damage to it but hopefully I could disassemble the rig if I have to, what I would like to do is take a good look at the gear box just under the headstock section to see if I can take a look at any of the headstock components passing through.

First things first though, i'll remove the chuck and belts and see what difference that makes, the turn pinion in the chuck are a little loose so maybe one is waggling around a tiny bit.

Michael W

Thanks for the feedback on this thread, it certainly helps me consider what's involved with getting a printer.

Call me a chicken but i'm veering over towards saving my pennies for a velleman over the i3, I realized both are heated, which is of course, vital for avoiding thermal shock on the surface if you're melting ABS at much higher temperatures than PLA requires.

I would say the aluminium frame construction of the velleman is a plus for me, but the cost point is also much higher as a result.

The prusa looks like a lot for the money you pay, and if I was really struggling for cash then it would be the one I would choose, however, the lack of clarity in the manual makes me feel as though a European designed one would lead me towards a risk averse outcome, and i'm not to keen or good at having to think on my feet!

I'm glad to hear and see that the quality of the parts produced doesn't suffer, even when the prusa is miles cheaper than the dremel ready-made.

It's also great having a knowledge of lathes and mills behind this for obvious reasons, you can engineer solutions to problems that a computing purist may not wish or be able to delve into.

And i'm sure if theres any problems on the surface finish you can always take a skimming cut on the machines?

Edited By Michael-w on 24/04/2017 10:50:04

I'm watching this one because I've been looking at the i3 prusa and turning green. So I've heard a lot of people complain about the instructions but at the entry level of the market I could nearly expect that.

It's a whopping great bit cheaper than the Velleman 3d kit printer, and has a heated bed. I'm tossing up between taking a gamble and possibly a bit of work or a kit produced by a trusted maker of electronics.

Michael W

Hi,

I've been doing a lot of work on my Clarke CL430 lathe recently and noticed when it's idle and I turn it that there is a clicking noise,

i'm sure that no gear train is engaged so it leads me to believe that deep within the gubbins of the headstock the wee little taper roller bearing is at least on it's way out.

Although this doesn't seem to have affected the work produced or any run-out, there are no tapers on turned shafts at least.

I would normally be the first to try and mount the challenge of gutting out the headstock and sourcing a replacement bearing to refit, having rebuilt nearly everything but the headstock, but I saw a video of a guy taking one apart on youtube and it looked very involved?

I only wonder to myself if I should be thinking about doing it in the first place.

If anyone wants to know what lead to this situation I think it might have something to do with me drilling out the motor pulley to a larger size and the inevitable happening of it going slightly out of centre, soooo, that would also be something else to redress.

I don't really push my lathe hard very often but it has done a lot of work.

I'll try to anticipate the "get a new lathe" comments, sorry it's not on the cards, just not an option.

Michael W

Edited By Michael-w on 23/04/2017 19:55:55

You'd better check the PCD of the bristles and parallelism between each stem. If I catch a 7 micron taper on that shaft it's in the reject bin!

PS. If you go onto aliexpress.com you can find all sorts of strange machines, such as designed for pen making and bendy straws, etc; if you ever felt in the inclination to stretch into the stationery or beverage accessories market.

Michael W

Edited By Michael-w on 22/04/2017 11:56:45