Member postings for mgnbuk

My first motorhome had been fited by a previous owner with a "Noise Killer" sound deadening kit that used a lead foil/foam sandwich.

Seems that the product is still available but it is quite pricy.

https://www.nkgroup.co.uk/product/noisekiller-lead-sandwich-material/ for those who like to know where a link goes.

Nigel B.

I used to enjoy Harrogate - it was easy to find, had good facilities, in a lovely setting; what a shame its owners priced it out of use. It is now named the "Yorkshire Event Centre", too, and its web-site shows very few public and trade-only events over the next few months.

Strange how different people find (in all meanings) different venus.

Doncaster & Harrogate are about the same distance for me, but I won't go to a show at Harrogate again due to the near impossibilty of getting in or out. The local roads cannot cope and the wider area grinds to a halt - particularly when the Yorkshire Show is on. Last show I attended there was a shooting show and, despite an early start from home that saw me leave the A1 around 7.30am, it took 2 hours to que from the A1 junction to the showground. Coming out I used local knowledge to get on to minor roads to come back a different route.

Doncaster, in comparison, is a doddle to get to & not usually any hold-ups coming from the Wakefield side. I do have the advantage of local knowledge here, though, as one of my brothers lived in Cantley (on the road out towards Bawtry from the racecourse) for a number of years.

Not been to a Midlands ME show since they moved out of Donnington Park - gone beyond comforatable day trip distance for me at the new venue. Probably the only shows I bother with now are at the NEC (non-ME related) - no parking issues, easy access & the last pre-Chinapox shows had edible fodder at not-too-eyewatering prices - such venues are never going to be cheap. When the ME show was at Harrogate the refreshment prices were no better than Doncaster IIRC.

Nigel B.

Seems like you have a pretty dreadful machine there Mr Lui.

To prevent you having to suffer further distress, I will risk all and offer you £100 to take it off your hands.

To be a little more serious - what are you expecting in the way of accuracy & rigidity from a small, bench top milling machine that the Emco brochure describes as being made "as priceworthy as possible" ?

The numbers you are quoting are ballpark for my Taiwanese FB2 clone (x2, as I am am on my second). Both of my clones showed no signs of hand fitting & I am not certain that the Emco machines were hand fitted either - I doubt that the selling price would have allowed that. The Emco brochure makes no mention or claims of accuracy & neither does the redacted Taiwanese copy of the Operator manual / parts book. No test certificate either.

Your points 1 and 2 could be improved or corrected with mild scraping & in all probability 3 & 4 could be improved likewise.

6 should be adjustable with the adjustments provided (gib strips).

5 and 7 are likely what they are and would require more expensive work to rectify ( hard chrome & regrind the quill body for a closer fit - regrind the spindle and maybe replace or re-engineer the spindle bearings).

8 I would take as par for the course with a light weight machine.

The tone of your comments suggest that you were expecting much "better", though I am not sure that any comparable machine would show "better" results ?

Nigel B.

If its for employees who are on site for several hours, don't install "chargers". Instead provide 13A (16A in europe) outlets and let the car owners use their 3kW "granny" chargers.

There are grants available to contribute to the installation of dedicated charge points - I doubt they would apply to 13A sockets. AC charge points can be 3 or 7KW in single phase, so a similar limit on electric costs could be achieved using 3 KW charge points.

AC charge points are not chargers - the actual AC charger is built in to the car. There is a basic communication between the charge point & the car when it is connected that informs the car of the capacity of the charge point, the car charger configures to suit the capacity then the a contactor in the charge point connects mains to the car. The "granny" chargers are not chargers either, just a mobile version of the hard wired charge point that communicates a lower supply capacity to the car.

Only DC "Rapid chargers" are actually stand-alone chargers - they connect to the car battery directly via a different socket, bypassing the built-in AC charger.

The grants scheme for installing charge points changes at the end of March (owners of individual properties no longer eligable for grants after the end of March) & the capability requirements of the charge points changes later in the year (June / July IIRC), so further investigation required before committing to an installation. A reputable, registered installer should be able to advise.

If you do go ahead with a public charge point installation perhaps consider applying parking restrictions to make the charge point bays for EVs only, with penalties for ICE cars that block them. One of the reasons I have not proceeded with purchasing an EV this time was not only the general lack of public facilities, but my observation that where they were provided they were frequently blocked by ICE cars. One public car park I visited recently had been provided with 8 charge points - 2 were "Out of Order" & 5 were taken by ICE cars when I arrived, all 6 when I returned.

Nigel B.

Edited By mgnbuk on 13/02/2022 11:57:19

I saw a video about the new Prusa machine & it appears to be very impressive.

£2200 assembled is a bit more than I am able to commit to a 3D printer without a Lottery win, unfortunately.

Nigel B.

The structure of Concorde got so hot special measures had to be take to allow for it.

One of the special measures was that the carpet was made to be able to stretch in one direction - IIRC the growth in length in flight was around 8". My late father was a carpet weaver at Firth Carpets in Brighouse, who made the special "strechy" carpets for Concorde.

Nigel B.

the drift in the position of the vise corner along the Y axis can be as much as 0.03 mm ..... This is just a 300 lb bench mill so high precision is not expected.

I suspect that a lot of small milling machine owners would be happy with a little over a thou movement ? What are you looking for or expecting ?

According to the parts book for the FB2 (well mine is a Taiwanese clone badged "FV-320T", but the manual appears to be a copy of the Emco original with the Emco badges redacted) the gearbox lay shafts run in plain bushes & it only has a small quantity of oil (can't recall exactly how much I put in, but probably less than half a pint) so it gets warm in use. Anything that gets warm is going to expand.

I am just wondering if the same happens to bigger machines and how people deal with it.

Oh yes - it definately happens to bigger machines ! How it is dealt with depends on how critical the parts are & how deep the companies pockets, but at one end is running "warm-up" cycles at the start of a shift to warm up ballscrews, spindles etc & build up lubrication films before starting to machine parts. That is how tight tolerance parts are machined where I currently work - 20 minutes rapid traversing the machine through it's working envelope with the spindle running, then run 3 parts with no blank in place, then start producing & the critical dimensions come out the same as at the end of the previous shift. Just put a part on the cold machine & they fail inspection.

Then there is actively monitoring temperatures around the machine & applying compensations to the axes to keep the tool stable relative to the part as temperatures change. I have seen a few variations of this method - Oerlikon CNC horizontal milling machines had a temperature sensor on the bed casting which was used to set the temperature of the lubricating oil circulated around the head casting to limit spindle growth, Or a Kearney & Trekker MilwaukeeMatic horizontal machining centre that had an Invar rod attached to the end of the spindle casting that rested on a dial gauge, with a resolver driven by the gauge needle - any movement of the resolver due to spindle casting growth moved the Z axis to keep the tool position constant WRT the job. Some modern CNC controls have inputs for multiple thermistors & compensations are handled through the PLC on the control.

Or there are temperarture-controlled environments. Only saw two of these while at my last employment (though former colleagues worked on two more temperature controlled sites - both defence related) & only one of them was actually functioning - the former DeVleig works at Red Lane, Coventry, which was turned off by the later owner due to high running costs & a printing press manufacturer in Leeds (Crabtree Vickers IIRC) which maintained the whole machine shop at 19C to better than 1 degree C all year round & had airlocks on all the entrances / exits. The machine I worked on there was a DeVlieg 5K120 jig borer with a 10 foot x 10 foot working area - after we had finished doing a CNC conversion on the machine, the owner had the positioning accuracy checked by an independant laser calibration outfit - it was found that the machine could position anywhere within the 10 foot by 10 foot area within a tenth of a thou - required because the bearing bores for the prining press rollers on the side frames only had a 4 tenths positional tolerance. Newsprint running at 30 mph through the press doesn't tolerate mis-aligned shafts !

Nigel B.

because I assume TESCO doesn't give away electricity for free

Not necessarily the correct assumption ! I don't shop at Tesco, but understand that some supermarkets do offer free charging (at lower rate chargers) for a defined period for users of their stores. And such use may require the use on the particular supermarket's "app" to get it going. From my POV, using the MG 5 as an example (as I have recently been looking into them), an hour on a 3Kw charger would put enough into the battery to cover getting me to and from the store (3Kw @ 3.5 miles per KwH). Not much, admittedly, but better than paying for my own petrol / diesel to get to the store and back ! Given the other "loyaty" enticements that supermarkets employ to gain your repeat custom, why not "give away" a small amount of electricty - is it that much of a difference to a small discount on the bill ?

The current requirement for multiple accounts, apps etc for the many different suppliers has been addressed by a recent govenment edict that all chargers have to be available by use of credit & debit cards at the charger. Still in the "grace" period for compliance IIRC, but a move in the right direction - after all, you don't need separate accounts, apps etc. to use petrol pumps. Kia have a card supplied to purchasers of their EVs that gives access to many different suppliers' chargers with the one card, billed monthly. Works throughout Europe as well, not just UK.

I have previously balked at the range issue for EVs as well - just so used to the "once a week" fill-up taking a few minutes & giving 550 miles to a tankful. As my weekly mileage is around 420 miles, I have range to spare, so a 200-250 mile range car seems inconvenient at best - barely 2 days usage. But you just need a different mindset - rather than the once-a-week fill to cover the week, think "when it is parked, plug it in". I appreciate that this really applies to those who can park near their property & have a charge point installed, but my car sits on the drive for 12 1/2 hours between getting home in an evening to going out again the next morning, so why not have it charging while it sits there ? If I could twist my employers arm to get a point installed at work (my brother has this at his workplace) it could be charging for 9 hours there. Plus an hour at the supermarket etc. - it all adds up. I came across an acronym on one EV forum that sums it up nicely - ABC - "Always Be Charging" !

So, realistically, with a small adjustment to how you "fuel" the vehicle, you come to it every morning / evening with a "full tank" . For probably 85% of my car usage, I don't think I would struggle with a 200 mile range EV - 100 miles a day commute for 4 days + around 20 miles for the weekly shop. It is the other 15% that is holding me back - the longer trips for leisure that would require using the (currently inadequate in my view) public charging network. The NEC is around 140 miles from me, so not possible to do the return journey on a single charge with even a "long range" MG 5. But I would be at the NEC for several hours, so why not "ABC" there ? Well it appears that thoughout their extensive carparks the NEC only have 10 EV charge points scattered about - a bit of a lottery as to if there was a free one when you got there & that it was working (unreliable / faulty chargers seem to be common complaint) & the subsequent "range anxiety" and delays to the return journey trying to find an unoccupied, working charger on the way home. The 400 mile trip to stay with friends in the Highlands would be similarly fraught & as for a touring hoilday abroad ....

Robert - have a read of the link in Hopper's post - seems such a system is being trialled, but the operators of the scheme are suggesting that it won't appeal to private users. It is more aimed at taxis, private hire & delivery vehicles whose batteries won't last a full shift. It isn't one large battery being proposed, but multiple instances of a small, standardised cell.

Probably a better solution to the charging issue than that employed by the Berlin bus network, though - their electric buses can only complete the mornning commute up till lunchtime on a charge & they can't recharge before the afternoon / evening stint. So they have a second fleet of diesel buses for that !

Nigel B.

the only dread I have now is being forced into an electric car!

Why "dread" ?

Apart from the initial cost, they are just a car with a different powertrain. I test drove an MG 5 EV last weekend & the most suprising thing about was how "normal" it felt to drive for the most part. Main difference was the adjustable regenerative braking, but other than having to get used to that I didn't feel it would take much getting used to at all. Range has improved over intial offerings, with the "small" battery version of the "5" being rated at over 200 miles - more in town.

My brother has been running a Nissan Leaf for 5 years now & it has proven to be a reliable, cheap to run car that he likes very much. At 6 years old (he bought it as an ex-demonstrator) the battery still shows 98% of it's original capacity. That he also runs a large Volvo diesel estate to tow his caravan touches on the point Peter Shaw mentions - currently electric cars struggle with towing. But that is changing too - the Caravan & Camping Club magazine had a towing test for a Skoda all electric car in the latest issue. Admittedly less towing capacity (1 tonne ) than an equivalent ICE car of similar size & the range drops (160 miles as tested) when towing, but a sign that EVs are evolving to meet user's requirements. I read (briefly) that Audi had recently done a towing test in conjunction with caravan maker Buerstner where the caravan had been fitted with additional batteries to assist powering the car via an umbilical lead & covered 250 miles on a charge through the Alps.

Whether mere mortals aan afford such technology is another matter, but ICE cars are getting more expensive & EVs are getting more capable and cheaper. The MG 5 EV I test drove costs about the same as a Skoda Octavia estate with a 1 litre petrol engine & DSG gearbox - and that is after the recent change to less favorable terms for the Government EV grant, No so long ago that the EV would have been 30% (or more) more expensive than a comparable ICE version.

I wonder if "right to repair" will be embraced by car makers ? When the CVT gearbox in the Avensis I had started making "bearing" noises at around 80K miles, Toyota were happy to inform me that there were no spare parts available & the only option was a new gearbox (no exchange option ) @ £4500 + fitting. I elected to move it on & put the money towards it's replacement - which was not a Toyota.

Nigel B.

I have not come across a "general" 3D printing forum - they seem mainly to be for users of particular machines or software / firmware, or appended to other forums.

Before I dived in & bought mine I mainly used YouTube for background information :

Thomas Sanladerer & Stefan (CNC Kitchen) are both German & have very good, professionally produced, English language channnels covering many aspects of 3D printing.

Teaching Tech & Maker's Muse are both Australian, both having a mix of topics at various levels.

3D Printing Nerd & CHEP (Filament Friday) are both American & also cover many topics at verious levels, but Joel @ 3D Printing Nerd is a bit more strident than the others.

There are many others, but those are the channels I seem to keep following. IIRC they all have a dedicated "so you think you want a 3D printer, but want to know more" type video that walks you through the basics

I managed to glean enough information from the above to feel reasonably confident about the process, setting up the printer & getting to grips with slicer software so that getting up and running when the machine arrived was relatively painless.

Nigel B.

Nigel what filament did you use for the bull wheel lock please?

Just a generic PLA, JC.

IIRC it was Anycubic brand PLA, white, printed at 200C on a 60C build plate, 5 perimeters, 6 top & 6 bottom layers with 70 % gyroid infill. The part was flat in the build plate, so the loads applied in service are at 90 degrees to the layer lines.

I have yet to venture beyond PLA, but from what I have seen (CNC Kitchen tests on YT particularly) PLA is stronger than the other popular options, but is more brittle & has a lower maximum operating temperature. PETG & ABS appear to be more ductile so don't fail as suddenly as PLA, but start to deform at lower loadings.

But take all that with a large pinch of salt, as I am still very much feeling my way with 3D printing !

The part in question has a lot of teeth in contact with the bull gear, so a lot of area to shear - the parts I printed are apparently holding up well so far in testing. I have a Super 7, so can't test them myself.

Nigel B.

I want to design and print a lock for chuck removal.

The post Ady1 linked to above has a link to a ready designed ML7 spindle bull gear lock.

I printed one for a contributor on that thread, who is testing it & will report in due course. From conversations about the Thingiverse lock, it apparently fits well and works as intended. Durability is still being assessed, but looking good last I heard.

Depends if you are just looking for a part to do a job, or looking for the design challenge !

Nigel B.

My absolute hate was the logbook and skill sheet task, I filled most of it in in the last few months with a number of semi fabricated jobs to get the skills ticked off.

+1

I was constantly pestered by the Training Offcer from the Halifax Group Training organisation that oversaw the EITB appenticeships for all the local engineering companies to get mine up to date and (eventually) completed.

While I was overseen by the Halifax GT office, I completed my training at Bradford Technical College between 1977 & 1981. I was one of the two first "technician" apprentices set on by Halifax GT & that required doing HND level college courses rather than C & G. Halifax Technical College didn't offer these courses, so I did the First Year Off the Job training & the FE element at Bradford. Being electrically biased, most of the time (around 12 weeks out of the year IIRC) was in the electrical section, but we also spent time on bench work (fitting), turning & milling, sheet metalwork, welding (gas & stick) and forge work for a couple of weeks at a time, mixed throughout the course. Friday afternoons were technical drawing in a classroom.

We also had the 8pm finish on the weekly college day - difficult to stay focused at the end of the day.

I have my module & log books in a box up in the loft & all the other certificates etc. in the "job application" file. Can't recall the module numbers, but something like "Electrical installation 1 & 2 " - I could risk going up in the loft to find out if it were of interest.

All gone now. In '77 there were 13 of us in the Electrical section on the First Year course, 3 of whom were technicians & all bar one were employed. The one who wasn't was sponsored by his GT office, who placed him before he finished the course. The next year there were 3 entrants, all sponsored, & the course closed after that. with the instuctor taking early retirement. Last time I walked past there (around 15 years ago) the old training school area was offices.

Nigel B.

Mick,

Have you checked the cable from stepper drive to stepper motor ? With the cable disconnected at both ends, check for continuity of each line + check for shorts between lines.

I have had X axis servo motor cables fail on 2 Cincinnati Sabre VMCs at work - the first went open circuit on one line & the second the inner & outer insulation failed & the lines shorted (which took out the drive amplifier & power supply ). In both cases the cable insulation (PVC) had gone hard and brittle, compounded by Cincinnati electing to use "cheap" cable outside the manufacturer's specification (too tight bends, not rated for continuous flexing & not oil resistant) - but they both outlasted the warranty !

Further to JH's motor wiring checks above, also check from each motor wire to the motor case - all should be very high (near infinite) resistance. If you connect each pair of coil wires together, one pair at a time (A+ to A-, then B+ to B-, with the motor disconnected from the drive) the motor shaft should become much stiffer to turn than with all the wires disconnected.

Nigel B.

Computers don't get ill, drunk, angry, tired, over optimistic, race other cars, or make mobile phone calls.

Indeed.

But computers rely upon software to operate & I'm sure we have all had experience of how infallible that can be !

Nigel B.

Have ordered new thrust bearing as these were cheap and strangely metric

A bit of a strange one - the parts list for a Colchester Dominion I found online doesn't show a thrust bearing there & in a list of bearings used shown later in the manual all are Imperial types.

Not to say that newer or older machines than the manual I found were not different though.

Nigel B.

i assume 46 is a fair bit thicker than the iso 32?

Yes, 46 is noticably thicker than 32.

The Gildemeister lathes at work use 46 hydraulic oil for spindle gearbox lubrication & the difference in thickness can be seen over 32 (kept for hydraulic top-ups) when decanting from barrel to jug.

Hopefully changing to the correct grade will sort your problems.

Nigel B.

I have had the one that came on a cheap drill press apart a long time ago. I can't recall exactly how I did it, but most likely using a 4" bench vice to provide the force as I don't have other means at home.

Turned out that the teeth on one jaw had stripped, so it was scrap anyway & not really worth the effort of getting it apart, given a Sanou replacement with the correct taper from Ebay was under a tenner delivered. The Sanou chuck has outlasted the no-name original.

Nigel B.

I would suggest that the specimen is definitely two stroke

I would equally suggest that it isn't - the position of the carb & exhaust outlet are just too far up the barrel to be a two stroke, but just right for a side valve.

Nigel B.

Strange way of indexing on a taper though

More likely "retaining" than "indexing" I suspect., rather like the Easychange holders.

Is the taper pressed in to the dovetail slide or retained with a screw ? Either way it should not be difficult to separate the two and put a parallel spigot in place of the taper - you could use it on anything then. I have something similar (but not as nicely made) with a parallel stub - much easier to set up for clocking a bore on the mill than a DTI arm lash-up.

Nigel B.