Here is a list of all the postings Will Noble has made in our forums. Click on a thread name to jump to the thread.
|Thread: Parkson M1250 Beast|
I'm in east Lincolnshire. Certainly anyone with any knowledge of these/similar things would be a very useful contact. That said, I'm trying to empty the space in the garage/workshop of building materials to let the electrician in to plumb that bit of the 3 phase, so not a panic job yet.
Nah! Nice thought but it's a roller shutter item. It would certainly stop it closing and probably a lot of nasty noises as it tried.
Happily, it's an illusion. The sides narrow in from about half way. I think it's also due to the slightly random placement of the bits of OSB. It was sitting on a pallet when we collected it and looked dodgy, even though it was a hefty one. We perched it on a pallet to start with, them chickened out and put it on the floor/OSB. There are fork slots under the back of the base.
Thanks for the responses, everybody. It's encouraging. Why did I buy it? It came out of a folded up business and at a price not a hell of a lot more than scrap value. I've never tried 'CNC' before, I was taught 'mandraulic' - a long, long time ago and only ever used that since. So I thought: 'What the hell!' 'I'll have a go'.
I've got the Heidenhain (TNC 151, or 155 series) manual for it but, sadly, not the Parkson bit. I know lathes.co.uk do some manuals but not yet sure how near they get to this one. I'd guess it must be one of the last of this series produced. There's no nod in the direction of manual reversion because having popped a couple of covers off there are no sockets for handles, apart from the right hand end of the table appears to have something of the sort. It seems from previous posts that it's probably salvageable, even if it's a question of going for a modern electronics transplant.
On the bright side, I've got 3 phase in the workshop - a legacy of an ancient offer of it coming in at the same price as single phase when the house was built, so the guy installed 3 phase (15Kw, blown air) heating as well.
There's what looks like a serious transformer behind another panel under the main motor at the back, so I guess it's where the 170 volts comes from. Next time I uncover it, I'll look at the servo motors, etc, for maker's labels.
The first thing I have to do is get the overarm lowered so I can get it through the door. It doesn't appear to be 'plug and play', with multi-cored cables running up the inside of the arm's box section and indivually connected and tagged onto long connector blocks in the control cabinet. I'm also guessing that old fashioned CRT is pretty heavy.
One interesting bit I've found is a B.Ae. label on it, Guess it's probably one of their cast-offs from the 90s? It looks a very well built item, just looks really massive because of all the panels covering up the drives. Quite a few are fibreglass.
Anyone any experience of them?
|Thread: Acrovu Capstan|
"It's a lot more than I paid for mine from Ebay. But that was over 10 years ago, when Ebay was still a proper auction site and there were bargains to be had'
Likewise my last for a roundhead Student - I was given it......................
Agreed the missing parts can all be replaced/manufactured but at that price, I think not.
I see the US eBay offering - missed that in my searches - is listed at USD 750, so perhaps that's where the inspiration for the asking price came from.
Not the same, I know but there's always the satisfaction of making one for the tailstock if it just doesn't add up. I'm sure I've seen whole capstan lathes go for little more than twice that.
I've been hangin' me liver over this for a while.
As far as I can tell, from having owned a similar item and also in reference to the scant information I can find, there seems to be a few bits missing ie:
5 of the long stop screws
The big 'T' locking/clamp screw from the top of the turret hexagon.
Some long buried memory cell also says there was a speed brace to adjust the stops as well. Any body own, or seen one for reference?
ps 'Chips in paint but in exceptional condition'? Really?
|Thread: Lathe crash!|
Did I miss something, or is the second incident and as the result of attempting to cut another thread, using a new bush in place of the one that failed, or is it from the original crash?
Other than that: Ref the oil oozing and the sparks, I hate to say it again - but I will:
It's almost certainly an 'Oilite' type product. Some have iron in them as per the quote I posted previously (hence magnetic and sparking when ground), all are designed to absorb oil which is then released as a lubricant for a bearing surface, most are quite easily compressed and have varying degrees of strength, usually quite low.
(It's how we used to get them out of blind holes - put a punch/screwdriver/nail against one edge, give it a tap and it readily deforms inwards. Pick out with pliers, or invert item and thump on bench/lump of wood.)
Could I also suggest that some enterprising designer has used the material deliberately? It can be extruded/press formed/whatever quite cheaply (why Lucas used it) in vast quantities and a bit of effort would provide a reasonable value for its shear point, thus enabling it to act as a back-up shear pin for the drive train - but perhaps in ChrisB's case, not high enough?
Edited By Will Noble on 30/12/2018 16:42:55
............ and I'm still going for it being an 'Oilite'-type material which has, as I think I implied/said, the torque transmitting ability of something approaching cast cheese. It's not designed to transmit torque, just soak up a lubricant and then act as a bearing surface.
If Chris is cutting a 16mm thread - and especially if 'going for it' - I'd suggest he's applying quite a lot of torque to the drive to the saddle, especially on a smaller lathe. It's revealed a design expedient (read fault/fudge/cost saving exercise).
The conversion to a suitable shear pin sounds a better bet - but chosen with care. I'd suggest a drill shank might not be appropriate - as in too high a shear rating for the job.
All the above assumes there is no other hidden damage which is causing a lot of 'drag' on the layshaft/feedscrew/saddle side of things.
ps I'm avoiding a discussion of my mention of Mazak. I think that bit is for another time/part of the Forum. Don't need another red herring.
Almost academic but my money's still on an 'Oilite'. It's a good bearing material for that situation, even if not very strong. Look at the texture and if it's grainy, most likely one of the Oilites, A N Other's version of it, or a sintered product. Many of them are iron-based.
I'd be surprised at MAZAK. It's not magnetic and has a very fine, silvery appearance if scraped with a sharp blade, like a highly polished aluminium alloy - and very soft. Old carburettors were made from it and had an awful durability on wearing surfaces.
Ah! Probably Oilite? - and unlikely to silver solder. If it does, don't think it will give up its oil, or act as a bearing surface very well afterwards.
Here's a brief description I found:
'Oilite bearings are manufactured in three standard materials. Standard Oilite oil retaining tin bronze is the generally specified material. It gives good balance between strength, wear resistance, conformability and durability in operation. Ideal in a wide variety of applications where self-lubricating properties are required over a long period of time.
Super Oilite® is an iron copper material suited to high static loads and slow oscillatory motion.
Iron Oilite® are 100% iron oil-retaining bearings which provide an ideal solution in high stress low revolution applications.'
The shear pins sound a better bet.
|Thread: Crankshaft repairs|
Hi Alan. I'm a Velo MAC owner. I'm currently glowering and cursing, awaiting the chance to finish a rebuild of a snapped (thrashed) crankpin and that's subject to finishing the garage/workshop rebuild on my new (to me) house. I'm a little rusty on the detail (and overseas at the moment) but I'll try and help if I can. I can only commend the Velo Club for help and an absolutely unbeatable source of technical help and information. It's a goldmine for a Velo owner and there are guys on there who have SERIOUSLY modded Velo engine to run on Nitro and Methanol for sprinting. They'll know what to use - but I never saw a standard Velo mainshaft fail from normal use, only pull through the flywheel (mine included) from the cush drive hammering at it - 'cos, as stated before, I thrash it!
Someone has mentioned 'top hatting' the inner end. I would! The alternative was a rollpin - but as it needs a new one..............
Someone also mentioned RADCO's book. The best source of info to be had between two sheets of cardboard, even after all these years. I have seen an electronic version somewhere.
The shafts were, I'm sure, case hardened/nitrided, definitely not through hardened. They need to be tough with a hard skin for the likes of the cush drive sliding parts. All the rest of the attached parts are fixed and don't rotate against them.
Have I missed bits, or which engine is it? Looking again at the pictures, there's a taper on the drive side shaft? - or is it so badly corroded? If tapered, is it a K series motor?
It's a very Velocette trick but if it's a MAC, or some KSSs (not the only culprits) the inner (1"ish) end of the mainshaft outboard of the bit held within the flywheel was ground on a fine, 0.001" per Inch taper, as was the bore of the 22mm bore main bearing. An original stock main bearing had two notches cut in the inner race to show which way round to fit it. They were, a while ago, made of unobtainium but I think (?) the club have had batches made again. They aren't cheap!
If you are making new shafts and originality is not a concern, then I'd be putting the biggest bore, single shouldered, roller bearings in there that wouldn't weaken the crankcase by having to take too much out the web bore and forgetting the expensive originality option.
The flywheels were malleable iron. It's very forgiving but has been known to lead to other problems with elongation of holes around crankpins - which is probably why my (Alpha version) bigend snapped. Veloce specified a 2 piece pin. The core was toughened steel, the bearing sleeve was through-hardened (EN36 ballrace steel?) so the pin flexed under load, the sleeve took the wear. The only version available to me was one-piece case hardened and it snapped at the root of the bearing surface. Oval crankpin hole didn't help, 2 piece pin would have survived but cheap construction method sealed its fate.
Either way, the Club is your best source of info.
I hope some of the above helps. I'll offer anything I can. If any of it's wrong - a big boy did it and ran away-----------------
Please keep us (just me if no one else is interested) up to date with your progress.
Edited By Will Noble on 23/12/2018 20:14:43
|Thread: Lathe crash!|
Sintered bronze, by any chance?
If so - and I remember correctly - it can be cast/press-formed into shapes ...... and also has a shear strength of something approaching cast cheese.
|Thread: It's a thread Jim, but...|
One of this sort of thing.
Old fashioned approach and going back a long time since I was taught how but I've often used them to finish threads, internal and external. I was lucky and picked up a load of oldies-but-goodies at a boot fair, then bought the ones to fill the gaps. I roughed the thread with HSS, sometimes carbide, then finished with one of them.
I know it doesn't address your problem regarding tearing but if the tearing isn't too bad and you have enough metal left, you can still use one to finish and rescue the job.
Apologies if the last bit of the above was an egg-sucking offering.
I know this thread has gone cold for a few days, but:
Have we all fallen out with using thread chasers - either manually, of in the toolpost?
|Thread: Drilling Bronze?|
Going back to my apprenticeship - which was certainly not yesterday:
The material heats up and therefore expands. With bronzes, that's quite a bit.
If you consider the item in this instance as a tube - forget the fact that you are trying to make a hole in a solid bar - when it expands, it gets bigger in every direction.
The outside diameter and length get larger, that's easy to see, but since the material expands in every direction, the metal on the inside face of the bore has to move and it does so inwards, ergo the hole gets smaller.
Add to above the material is 'sticky', the drill heats and expands as well and you have all the makings of a *** of a job.
That's my twopennerth - which I hope has reassembled Martin's mind.
A bit late adding to this but:
As a result of absolutely no experimentation whatsoever, how about a SHARP, carbide tipped, masonry drill, possibly even one of the spear pointed tile drills?
If you are just making a hole to be bored to size (usually the case) then accuracy of size should be no concern and the carbide tips are usually larger than the drill tip and the drill itself just there to hold the tip(s) and provide flutes to clear waste.
(fire away, I've got my tin hat on)
|Thread: Carbide Insert decode|
Wow! Thanks, every body. Lots to digest from the links and posts, alongs with charts to peruse. Muzzer's caveat reference Rik's link to the US site is noted. I've found and read the article suggested by Richard and bookmarked all the links for a bit of reading.
Neil Wyatt's post almost does it without further reference Thank you.
I have a Canela SDNCN2020 facing tool (the only one) that came with the lathe. It takes DCMT inserts and I bought a boring bar and a SDJCR1616 rightward surfacing tool at Doncaster that takes the same type/size for the very reason XD 351 says - to cut down on stock range. It would seem my instincts weren't too far off but what sparked this question was looking at all the options and thinking 'what a minefield, when you don't have the basics'.
That little selection now gives me the basics, I think. The tool bits Neil Lickford listed gives me a clue to the grades I'll be after. His second photo, the PR1125, looks remarkably similar to the one that I used in the little Valenite holder I had all those years ago. It didn't have a central clamp screw, it sat on a pin and was locked from the side by a wedge, held in by a screw, if I remember right. It got used for just about everything short of boring holes.
A largish, 20mm shank Sandvic boring bar with triangular inserts came to me, so it seemed silly to refuse, I know I'll end up using it quite a lot and the inserts now seem fairly simple to find.
Having heeded warnings about QC T2 toolholders, I checked those on offer at Doncaster and noted the RDG variety seemed well finished and to fit the QC post very well. I now have four holders to play with. More needed.
In the midst of all this, I need to find some butt welded HSS tools. In the past I used a Myford set. A bit diminutive on my old Student, more so on this Master but still very useful. I think a new set is in order.
The only wish list bits I couldn't get at Doncaster were any of the D1-4 things. RDG, amongst others, stock it but hadn't any there. I guess it is, after all, a Model Engineers Exhibition and my stuff is a bit on the large side for that.
Once again, thank you, everyone.
Starting again, almost - but not quite - from scratch, I find myself bedazzled by the plethora of carbide tipped cutting systems in use today compared with 15 years ago. In those days I had three inserted tools, one for surfacing and two boring bars. I was given them and they were all Valenite. The rest were HSS, with a couple of brazed tip carbide items for the heavy stuff.
Now there are dozens and dozens, some VERY cheap and probably VERY poor durability.
I've looked around for a decode and compatibility chart, can find several that do some aspects but none that provide a reasonably comprehensive chart, or table.
What does everyone use as a reference/decode/database, or chart?
|Thread: Ainjest High Speed Treading Unit on my new Master 2500|
Looks like I'll be making use of it. I'll work out the intricacies of Metric threading once It's all set up and running on Imperial. I do most certainly cut Metric threads as well, so this looks like it's going to be fun..........
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