Here is a list of all the postings mgnbuk has made in our forums. Click on a thread name to jump to the thread.
|Thread: The Workshop Progress thread 2018|
I'm not sure if a lathe boring bar will work as they tend to set the tip at an angle
Can't see why it should make a difference ? If I use the boring bar in the lathe (set correctly on centre) to machine a bore larger than the minimum specified for the tool in a rotating workpiece, or rotate the same bar set on centre in a boring head to generate the same diameter bore in a stationary workpiece, the tip is presented in the same way to the bore regardless ?
I have used larger diameter lathe boring bars in larger than ME size boring heads at work (admittedly into graphite components, not metal) & they have worked fine without rubbing, and have also mounted lathe internal screwcutting tools in milling chucks & using them as fly cutters for thread milling on CNC milling machines.
I have the bars I linked to & intend to try them in my 2" boring head - just require the 1/2" to whatever reducing sleeves making to be able to try them out. I'll report back after doing so, though these projects do seem to take longer than initially anticipated !
How about one of these Ebay 352259180098 & turn it down from 10mm to 3/8" ?
Also available in 6, 7 & 8mm diameter taking the same CCMT0602** inserts to sleeve up. Searching "SCLCR" brings up most of them.
|Thread: Warco WM250 Lathe and Warco WM18 Milling machine (Advice please)|
We get a lot of raw material & finished parts from China at work & very rarely do the containers turn up "on time", due to many factors. The source factory can be late shipping, ships get delayed by weather (we have had containers delivered to Rotterdam instead of Felixstowe due to weather, then lost 3 or 4 weeks getting it back from Rotterdam to Felixstowe again). Even when your container does get into the UK, some get impounded at random by C&E for X-ray checking, which can take over a week (for which you are charged storage by the day !). And rarely can the shipping agents give any kind of delivery update until the day the container is actually released to them at the port.
It is not good for the blood pressure when you have "late" parts that have to get to customers to keep production lines running & you don't know if they will get to you on time. 4-6 weeks "late" from intial estimates given 3 or more months previously is not unusual & no amount of huffing and puffing on our part will get "late" shipments to us any quicker - it arrives when it get here & not before !
I enquired about a WM18 with an MT3 spindle recently (not currently shown on Warco's website - they seem to have standardised on R8) & was told that one could be special ordered no problem & delivery would be the normal 5 months - it is a long supply chain ! So it is quite likely than Warco got an estimated delivery date at the time they placed their order several months back & genuinely don't know when the container will actually turn up if it is "late".
And Warco are not alone in this - SPG are OOS of their equivalent milling machine at the moment - the answer to my restock query being that delivery "should be next month". It must be just as frustrating for suppliers not to have stock to sell & not knowing when it will appear (due to circumstances beyound their control) as it is for you as a customer - you could try cutting them a bit of slack.
|Thread: Mobile Networks|
Does anybody still do a real Pay As You Go?
Yes - I use Virgin for both landline, internet, TV & mobile. As a landline user, they have a lower rate for PAYG (8p/min & 8p texts, with free Virgin - Virgin calls & texts). I top up £20 every 18-24 months (no time limits).
I did have a data only contract tablet with EE. It worked reliably enough in the UK, but was useless abroad. Getting EE to cancel the contract at the end of the signed-up period was made especially difficult by EE & I would not choose to use them again. Currently have a pre-paid 3 data only Sim for the tablet - £27 (IIRC) for 24Gb over 2 years & works equally well home or abroad.
|Thread: Glass-scales-ZX45-RF45 clone|
Y-axis scale mounted at the rear of the table leaving the front clear
In normal industrial parlance, that is the X axis (table left-right movement) - the Y axis is the table front-back movement.
Nice installation, with the table scale in the "optimum" position nearest the fixed dovetail (opposite side to the gib strip) . I am currently looking at a 3 axis DRO for my FB2 clone & it oden't look like I have enough room to put the scale at the back of the table without restricting an already short (140mm) Y axis travel.
|Thread: Aldi 3 drawer steel toolchest|
Bought one of these **LINK**
along with the shopping this morning.
While not super high quality, it seems reasonably well made. It was well packaged & undamaged when unpacked. The outer chassis & lid are approx. 0.8mm steel, with the drawers being approx 0.7mm. All drawers & the top area have liners, with the first drawer being segemented for small parts or tool storage,
A drop-in bar secures the drawers when the lid is closed (the bar is in it's "parking" position on the left of the picture - it locks the drawers when inserted in the slot at the back) & two keys are supplied for the lock. Not sure why there is a "mousehole" in the back wall on the right - any ideas ? Finish is satin red & appears well applied. According to the Aldi link, black units were also available, though my local store only had red.
Another step towards organising the garage / workshop & reasonable value for £40. At the time of writing, these are still available to mail order from the Aldi website if you don't have a local store or they are OOS.
|Thread: Aircraft General Discussion|
Or, given Sam's location, possibly CAC Wirraways.
|Thread: Warco WM250 Lathe and Warco WM18 Milling machine (Advice please)|
To check if the quill is perpendicular to the table, proceed as follows :
Fully extend the quill and clamp it.
Then repeat the process, but with the dial gauge set on the side of the quill & "wipe" it with the Y axis (table moving front - back) rather than the X.
The readings "should" be pretty well the same top & bottom from both setups - my guess is that the side value will be close & the front value will be out.
|Thread: Where to get a running bearing for Ajax AJ8 mill|
1 1/2" Od x 1 1/4" Id x just over an inch long hardened & ground inner bearing ring.
Press or glue 2 onto a 1" bore x 1 1/4" Od sleeve & away you go.
Quite a range of Imperial bearing inner rings readily available - precision ground hardend parts at reasonable prices
What about using needle roller bearing inner ring(s) ?
May need to use more than one is series, but I don't think that would cause problems.
|Thread: Anyone fancy a larger UK made milling machine?|
Seriously, do they normally machine steel dry,
Yes. IIRC one of the reasons being that the inserts need to be kept at a fairly constant temperature, so coolant needs to be a very strong flood. This is not always possible & is difficult to both guard & collect. Intermittent application of coolant to hot inserts can lead to failure due to thermal shock. Again IIRC, the idea is that most of the heat goes into the swarf, but I have regularly come across operators keeping a pair of welding gloves to hand to change tools, as the tool bodies can get hot enough to burn you. Insert drills, though, need high pressure through-tool coolant to blow the chips out of the hole - that really does go everywhere !.
the Mandelli factory in Piacenza in the late 1980s, they were capable of such work rates that it was refrigerated before re-use.
That may have been to keep the workpiece cool to maintain tolerances. I have seen some machines that use temperature controlled coolant circulated through the machine to keep the machine structure cool for that reason - including through hollow ballscrews via rotating unions. As Mandelli were manufacturers of quality boring machines, I would expect that they took dimensional accuracy of parts seriously.
I'm not sure that the "UK made" bit is true anymore - pretty certain they announced in the trade press that they were not going to be building their own machines here anymore & were going to be concentrating on the agencies a couple of years ago.
|Thread: Faceplate or Independent Chuck?|
If you accept the 'minimum two threads engaged' rule
I work to the " jaws fully engaged in the body with no overhang" rule wherever possible - "two threads engaged" is a new one on me & way outside my comfort zone.
How would your capacity calculations work out for full jaw engagement, Neil ?
|Thread: John Stevenson|
Sorry to hear of John's passing.
My condolences to his wife & family.
|Thread: Faceplate or Independent Chuck?|
Surely the 4.5 kg mass of the 6" chuck, especially if compounded by an off-centre workpiece adding to the centrifugal forces, be more than the headstock bearings and motor power are designed for and would put great strain on these items. The C3 mini-lathe is probably not designed to take anything bigger than the 100mm (4" chucks.
A standard mini lathe appears to use 6206 deep groove ball bearings fpr the spindle. If you have a look at the ratings for a 6206 bearing, you will see that you will not have an issue with overloading them. A heavier, larger diameter chuck will be advantageous when doing interrupted cuts - it is a large flywheel & will help both the gearbox & the (relatively weak at low revs) motor under such conditions - mini lathe owners on other forums have fitted 5kg 5" 3 jaw chucks without problems & report better finishes using these..The heavier chuck does take longer to accelerate & decelerate, though. But if you feel happier with the smaller chuck, go with your feelings (just watch your digits if you run it with the jaws protruding !).
Not sure what MG means with regard to MB's picture - as the jaws are inboard of the 6" chuck body OD, the jaws are not running in the gap - a Myford will swing 7" over the bed after all. The jaws are running over the gap area, but not in gap.. That configuration would run without fouling on a C3, which also swings 7" over the bed.
Is that a tumbler, MB ?
the jaws are still going to hold the same size whether they are overhanging a 4" chuck or in a 6" chuck that isn't overhanging.
But the job held in the 4" chuck will not be as secure, due to less of the jaws being supported by the body and less screw engagement. Also, the overhanging jaws will not be visible when the chuck is rotating - potential for an inadvertent operator / moving jaw interface - the operator always comes off worse in such situations. Certain lessons drummed in at Apprentice Training School 40 years ago still resonate !
I think 6" is too big for Colin's lathe.
A C3 mini lathe swings 180mm, according to the Arc website, which is 7.08" - or about the same as my S7. A 6" direct mount fits a S7 fine, so should also fit a C3 fine, though the body will be closer to the bed due to the lack of a gap.
You aren't going to be able to open the jaws of a 6" chuck very far on a 3 1/2" centre height lathe...
But you can open them to the edge of the chuck body - extending jaws beyond the extents of the chuck body is generally regarded as bad practice *. And opening the jaws to the OD of a 6" chuck will allow larger pieces to be held that doing the same on a 4" version.
* and yes, I know we all do this at some point and to some extent, but that doesn't make it any less bad practice !
4 jaw independent, as large as you can fit (probably a 6" & slim body you can get one to fit to minimise overhang.
Used to hold square, rectangular & irregular shaped objects, not just to set off centre. Also used to accurately centre round items - more accurately than a 3 jaw self centring chuck can usually manage.
Faceplates more for special setups, like using a Keats angle plate **LINK**
or to hold castings that don't lend themselves to holding in a chuck. The mini lathe faceplates seem too small to be useful to me (space needed for clamping arrangements), plus the cast slots seem very wide & rather short.
I have the 7" & 9" faceplates for my Myford - not used either in anger yet, but use the 6" 4 jaw regularly. The advice to those starting out who could only afford one chuck initially was to go for a 4 jaw independent over a 3 jaw self centring. Might take a bit more setting up on round work, but more versatile.
|Thread: New chinese lathe or old Myford lathe|
When I was initially looking for metalworking capabilty at home (some 25 years ago), my first thoughts were to go for one of the Chester lathe mill combination machines that were advertised in the motorcycle magazines. Seeing one in the flesh at a classic bike show was a bit of an eye-opener - there was so much play in the various moving parts it felt worn out straight from the crate ! At the time, this was pretty well the only mainland Chinese machine available for the hobby market, with the other affordable (relatively !) small machines being Taiwanese or East German. My thoughts changed to a CT918 lathe - basically an Emco Compact 8 & still available until recently from Chester & Warco. - and the saving began.
My father had bought a Boxford CUD from one of his customers - he didn't particularly want a lathe, but the seller wanted rid of it and the pillar drill Dad really wanted in one transaction.. After it bit him (thou shalt not start the spindle with the chuck key still in the chuck ...) it got no further use. When he passed away, I bought the lathe from my brother (who continued to run my father's business for a while & the machine was a company asset.).for a nominal amount.
A mid-'60s ex-school CUD that had ended up in a clothing manufacturer making press stud insertion dies, it was not in bad condition, but had been greased through all the oiling points. So it was completely stripped, cleaned, repainted & rebuilt. Over the course of a couple of years, I managed to get most of the missing change gears, a direct mount 6" 4 jaw chcuk, faceplate, QC toolpost, a boring table (the lathe was pre-tee slot cross slide) & a travelling steady - never did manage to find a fixed steady. This was pre-Ebay, so the bits came from dealers, Auttjumbles & ME exhibitions. It worked mostly quite well & was accurate, but the under drive was a pain. As the final drive belt has to pass through the swarf tray, it has to be a link type belt. The original that Boxfords used was of a canvas-type material & that worked OK-ish, but was in poor condition. The new types are made from a plastic material & slipped badly under load depite being bow-string tight.
Skip forward a couple of years & I was on-site at a machine tool dealer fixing a machine that the company I worked for at at the time had retrofitted a replacement control to. They had a pretty clean, mid-'60s ex-school Myford Super 7 - direct mount 3 & 4 jaw chucks, faceplate, catchplate, taper turning attachment & 3 sets of change gears (there must have been 2 more lathes somewhere else gearless !). My milling machine fund was depleted to the tune of £825 & it came home with me a couple of days later. My thinking at the time was that I would get it cleaned up & use it, determine whether I prefered the Boxford or the Myford & sell the looser. The Boxford went. For what I wanted to do (and still do for that matter), the Myford was nicer & more convenient to use (speed range, ease of speed setting & the spindle clutch particluarly). Selling the Boxford & accessories raised far more than the Myford cost, so the milling machine fund was reinstated.
I found a fixed steady at an Autojumble a fortnight later (never did find a Boxford one) & a couple of years later bought another (poor condition & damaged) Super 7 B of similar vintage to get the feed gearbox. The gearbox was swapped to my lathe, parts that were beyond redemption on the "scrapper" were purchased new direct from Myford & fitted to my machine, with my good-but-slightly-worn bits intended to go into the other. A friend wanted this machine after I had done it up, but he died suddenly before I finished it & I lost interest after that. It went as parts on Ebay, raising more than it & the new parts had cost - effectively a free feedbox , leadscrews & nuts on my machine.
Used machines, as has been said, are a lottery & the quality of the Chinese competion has come on leaps & bounds since I looked at the Chester Multi-purpose machine 25 years or more ago (and shuddered !). The newest "original style" Boxford will be 30 + years old now & they were not made in the quantities that the Myford 7 Series machines were, so availability is not as good. Finding accessories at a reasonable price (or just finding them period) was a chore over 20 years ago & doesn't seem to have got better. Find a nice, fully equipped machine & it may be a better buy than a Myford or a new Warco etc., but if I were to start out again I would probably go the new route. Had I bought the new 918 I intended to had fate not intervened, I would most likely have made more "stuff" and spent less time rebuilding !
|Thread: Flexible Ratchet spanner challenge|
Local Aldi today were "remaindering" a set of 5 or 6 flex head ratchet spanners (from 8-19mm AF IIRC) for £4.99 the set - 3 year warranty too. Quite a pile of them to shift. As SWMBO was with me on this occasion (car in for looking at) I was forced to resist !
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