Member postings for Simon Williams 3

Oh dear! Having the Autolock chuck taper refuse to let go isn't good news, but don't go bashing it any harder just yet, there is too much to lose by damaging the internals of the quill. There is much on the forum about the troubles of removing a stuck MT2 taper, with suggestions about the cause being fitting a cold taper into a hot socket, as the pair of them cool to a common temperature the taper socket shrinks onto the arbour, and it can be a devil to get them to let go of each other. It sounds from your description as if this might be your starting point.

The answer is hopefully hidden in your second question about the threaded backing ring with three tommy bar holes.

You will have noticed that the thread in this is left handed. The purpose of the ring is to be snugged up against the nose of the quill taper, this stiffens the tool set up and changes the resonances to compensate for the shortcomings of a No 2 morse taper fitting.

What you can do at this point is to use the threaded ring to pre=load the taper in the "coming apart" direction. There is a pair of spanner flats on the nose of the quill, but you will need a very thin spanner to get onto them, so you may have to hold the body of the chuck to allow you to push the nut firmly up against the nose of the quill.

Tighten this as much as you can up against the nose of the quill, hopefully without brutalising the tommy bar holes in the ring, which is hardened so don't be too frightened of it. The idea is to establish a significant preload pulling the male taper out of the quill by pushing the ring against the outer end of the quill.

Now lock the quill (ball handle LHS of the quill). Now smite the end of the drawbar sharply, having made sure that it is loose and there is a bit of clearance under the head of it.. I'd use a copper hammer for this, you need a good sharp crack to break the taper. Patting it with a soft hammer or through a bit of wood won't do any good, and I think your 3 lb hammer is a bit too heavy, I'd go for something maybe half that weight.

I've got a face mill which jams every time I use it, I haven't broken anything yet by hitting the drawbar with a 12 oz hard hammer. No idea how brutal is too brutal!

Give it aa couple of good whacks, don't keep beating it if it won't come loose. If it won't we're into thermal shock as the next resort, but you need some dry ice to cool the Autolock chuck and that's going to be difficult at the moment. Ice and acetone will also work as a freezing sulution, but that's getting even more complicated.

I'm charging the camera battery at present, and will post some pictures of how to assemble the chuck - hopefully correctly - later.

Do let us know how you get on.

HTH Simon

+1 from me on Martin's suggestion to check the drive belt. The two cheek plates pull off the side of the assembly to expose a pair of four speed cone pulleys and a dear little vee belt. The state of that belt will shape your experience with using this machine.

So much so that I suggest you buy a new one and just fit it. If it is the same as mine it is an SPZ500. Changing this on mine made a disproportionate improvement to the amount of power actually reaching the cutting head, and also the smooth running of the machine. It is tensioned by loosening a nut to the right of the motor mounting flange and swivelling the motor.

Changing the belt is a matter of locking the quill fully extended, now the belt will pass over the top of the spindle pulley and under the bottom of the motor pulley. Or at least it does on mine.

Have you perchance the rest of the Autolock chuck stashed away somewhere? If you would like a picture to explain what's missing let us know!

HTH Simon

I have a theory, and hopefully someone who understands the chemistry of what's going on will be along shortly.

My impression is that if the gismo with Duracells in it has a proper mechanical switch - a true off switch - then the batteries last well, and are "reasonably" trustworthy.

On the other hand a lot of modern electronics has a push button on/off switch, which just sets the gadget in a state of hibernation. If so, the continuous off state current - however small - will eventually discharge the cell.

It seems to be what happens next which matters - if the gadget continues to present a current drain on the flat cell then it's only a matter of time before the cell leaks, initially a clear fluid which rots everything it contacts, then turn in due course to a white crystalline deposit on the battery enclosure. Neutralising the sludge with acid is fine, now how do you get rid of ALL of the acid? Answer - laboriously.

On the other hand, if you take the flat battery out of its gadget and throw it in a box for re-cycling, it's still sealed a couple of years later. I've tried it - it takes me ages to "get roun'tuit" to take the battery collection to the tip I mean re-cycling centre.

I have a variety of Sennheiser body pack wireless microphone transmitters and receivers I use for a local fete for the PA. I have found from bitter experience its is essential to remove the batteries from each item before storing them over the winter. The batteries are perfectly safe (famous last words) so long as they are NOT in the bodypack - where there is a miniscule standing current of a few microamps, but I have lost at least two systems by being careless and failing to remove the batteries before storage.

HTH Simon

Long ago, in a galaxy far far away I built a hover craft for the son of a neighbour as a project linked to the Neighbourhood Engineers initiative of what was then the IEE.

To be strictly accurate I built the transmission, my neighbour's son and his sixth form buddies built the hull and the rudder mechanism.

It was the type of hovercraft which uses a single engine for lift and propulsion, about the size and looks of a rubber dinghy with a tail fluke. It had a Suzuki 250 cc bike engine coupled to a big Breezamax fan, with about a quarter of the resulting draft directed down into the skirt. The mountings for the fan and engine with a chunky toothed belt drive was the bit I contributed.

My principle recollection of it was that I took the responsibility of the initial trial, so I revved up the motor and it lifted off the ground and set off. Letting off the throttle caused it to sink immediately to the ground, whereupon it threw me out of the front as it came to a direct and very abrupt stop.

But the main difficulty I had with it was I never got the hang of the steering - or rather the lack of steering. We had the use of the local school's football field to play with it - imagine a completely flat grass field of about 4 acres, with rugby posts at each end. Try as I might I could not escape the magnetic and overpowering attraction those goal posts had for the front of the hovercraft. I think I collided with one or other of the goal posts three times.

There are clubs who race these things over land and water - and my neighbour's son had his heart set on joining in. I left him to it!

Ho Hum

Simon

Hi Pete, thanks for those kind words, good to hear you manged to wiggle the lead screw out successfully.

Given the wear on the lead screw, you might decide to replace it. I have doubts if you'll find a new direct replacement, but the lead screw for the Mk2 S7 can be altered to fit, though I fancy you'll need a lathe to do it. Essentially the old screw is shorter than the new one, I can't remember if it needs a shoulder turned on the end to take the drive gear, when you're ready post a picture and we'll fathom it out.

Where are you? If you are anywhere near West Glos UK I'd be pleased to help. Of course that's not going to happen for the foreseeable future while this corona virus stuff is going on.

In passing, I checked the serial number of mine, it is SK 3534 which I believe makes is vintage 1953. Two years older than me!

KOBO

Rgds Simon

Morning Pete, welcome to the Myford "it's older than I am" club - which mine is. I've got one looks exactly the same in my shed, love it to bits. It's a little bit older than this but it's a trooper.

Two little jobs to recommend to you if I may:

1. Clean the half nuts, as that is almost certainly the cause of the thread wear you show on the leadscrew. That means withdrawing the leadscrew - the bottom nut will come out downwards but the top nut is held in by the lead screw. But I bet the halfnuts are full of an abrasive mix of compacted swarf and old oil, which is abrading the lead screw and stopping the half nuts engaging fully.

This means removing the leadscrew, come back to that.

2. Cover the ventilation slots in the motor. The more modern version has a totally enclosed motor, but this one is vulnerable to bits of swarf taking a hike down the openings in the motor. Can be exciting.

Going back to taking the lead screw out, I think I'm right in that the leadscrew you have does not go right through the gearbox like the later one does, so all you do it remove the little cover RHS of the QCGB and unto a grubscrew (maybe two?) to loosen the drive gear just inside. With the half nuts handle removed, now remove the two screws at the tailstock end of the leadscrew which mount the RHS bearing to the bed of the lathe. The lead screw with hand wheel, bearing bracket etc should now slide to the right, out of the half nuts. I haven't done this for ages, if anyone else knows different or I've left out a stage please correct me.

One other comment - you have the (contemporary) Mark 1 gear box there - if you get into playing tunes on the gear train between the mandrel and the gearbox to cut threads other than those shown on the gearbox legend plate you need to know that your gearbox runs at half the speed of the later Mk 2 gearbox. Plenty on here to explain what that does to the arithmetic, more anon.

And lastly, my take on the bed wear issue is that unless it is completely outrageous it is survivable, and getting fixated on whether the bed is parallel is not necessary.

HTH Simon

Mornin' all

Methylated spirit will dissolve emulsion paint - albeit slowly.

HTH Simon

Assuming that the seventh way is for an earth connection, my preferred option would be this:

Harting 6P plus E

HTH Simon

Edit - re-reading the prior suggestions I see Robert is (as usual) ahead of me.  Apologies.

Edited By Simon Williams 3 on 27/03/2020 13:56:12

Something mighty peculiar with that, unless you were doing something crazy - I assume not.

Either the VFD is current limiting, or the motor is still wired in star not delta, or perhaps both?  Any which way round, mine won't stall with the original 1/2 HP motor unless I go brutal, and we wouldn't want to do that would we?

HTH Simon 

Edited By Simon Williams 3 on 25/03/2020 10:14:36

Those two statements are mutually exclusive.....

A Condition Report on an installation would, I hope, encompass a pretty exhaustive visual examination as well as appropriate testing.

Rgds Simon

Well, firstly there ain't no way a 5 amp BS1362 fuse is going to let enough energy through to start a single phase 1/5 HP (Edit correction 1/2 hp) motor. Not nohow.

13A fuse is going to be perfectly safe, provided:

Motor and wiring are adequate for 20A continuous current ('cos it takes at least 20A or thereabouts to blow a 13 amp fuse)

Earthing is good (I typed god, maybe that's a better sentiment!)

Motor and switchgear insulation is adequate.

Single phase motors take something in the region of 8 times full load current (more if they can get it) briefly while starting. The fuse has got to let enough energy through to get over this hump, after the motor is up to speed the line current falls back to something akin to what's on the rating plate, but you also need to take into account power factor (lousy). The other hazard is that running a brief transient load of about 30 amps through the house wiring and a typical 13 amp socket limits the available current because of the upstream wiring resistance, contact resistance in the socket outlet, and the resistance of those horrible bent metal pegs connecting to the fuse in the plug top.

I don't have the I squared T diagrams in the IEE Wiring reg's to hand - they're at work and I'm at home. These dictate the rights and wrongs of the fuse characteristics for this application. A 1/2HP motor should have a thermal overload device protecting it, if there is a working internal thermal trip so well and good, otherwise you need a contactor/overload arrangement as well as the 13 amp socket on the wall. A 13 amp fuse will do just fine, but don't be too surprised if it blows on repeated quick motor starts.

In short a 13 amp fuse will be perfectly OK provided the wiring is made with 1.5 mm2 or better 2.5 mm2 cable, But do please get someone with a proper calibrated insulation tester (NOT a multimeter) to check insulation at 500 V DC and earth path resistance for safety reasons.

HTH Simon

PS Waste of time my offering to do the safety checks at the moment - I'd gladly do so if you are local (West Gloucestershire) but not just at the moment.

Edited By Simon Williams 3 on 24/03/2020 11:08:56

I've been doing some armchair research into alcohol as a sanitiser, and I seem to have concluded that the alcohol content needs to be 90% or higher to be effective against the coronavirus.

I've also investigated the published information about methylated spirit, de-natured alcohol, rubbing alcohol and IPA (iso propyl alcohol)

With the possible exception of IPA (though it seems a big vague what you are actually buying) the others don't seem to necessarily meet the 90% alcohol criterion, so I conclude they are not necessarily effective against this particular virus. I'd hate to put my faith in something which turned out to be ineffective.

As others will by now have followed, the virus hates soap as its outer shell is a fatty protein and breaks up on contact with soap or detergent. I think this is why the medical advice has been that hand washing is the preferred and effective countermeasure against contamination, and alcohol based sanitisers are a second best expedient in the event that proper washing is impractical.

Soap, liquid soap, detergent, washing up liquid, shower gel, shampoo, take your pick, whatever is to hand.

HTH, stay safe!

Rgds Simon

'ang on a minute chaps.

All this stuff about stiffness of the spindle is irrelevant - the power you can get to the cutter is limited by the drive belt. For those not familiar with the TS light vertical head,, it uses a Z section (3/8 wide) vee belt, 500 mm long. With only a slide and clamp tensioner. Modifications could be made, but they'd be fundamental to get a bigger belt and or a screw tensioner in the mix.

FWIW I use a 40 mm diameter shell mill with APTK1604 inserts, depth of cut about 0.5 mm and feed pretty gentle, as you don't want the cutter to stall 'cos it chips. You can use the cutter in either of the two bottom speeds (approx. 200 and 400 revs) - it makes no never mind just so long as the cutter keeps cutting freely.

The amount of metal you can shift is limited by the power at the cutting edge, not the stiffness of the machine.

My cutter arbour is MT2, yes it would be nice if it was stiffer but that ain't the limiting factor.

It's a light vertical!

Rgds Simon

Hi again, the reference I remembered for decoding the serial number is this link:

Serial Number stuff

It's quite a long thread, the post dealing with serial numbers is by Miles Hellon dated 3.1.2019 about half way down the second page.

You might also like to have a look at this:

Tom Senior LV Repair

HTH, welcome to the Senior Citizens Club.

Rgds Simon

+ 1 from me NOT to fit a bigger motor - it's front flange mounted so it's going to be quite a job to marry a bigger frame size onto the top of the head, but you'll never use the extra power anyway - the dear little vee belt is only a Z section and there is no way of tightening it hard, so don't bother. I regularly use a 40 mm face mill on mine in either of the two lower speeds, it's possible to stall the cutter because the belts slip (edit - correction - belt slips!) but it's a great deal more difficult to stall the motor.

It's a lovely machine, treat it kindly!

I'll find a previous post discussing serial numbers in a mo, there's something in an earlier thread. More shortly.

Best rgds Simon

PS Pictures of mine and various repairs in my album.

Edited By Simon Williams 3 on 10/03/2020 20:33:58

I think the clue is in the fact that it started OK the first time, and only made the straining noise when you moved the switch. That's a faulty switch. No I would definitely not be happy to let that go out of my shop behaving like that, but I think the fault is in the rotary switch.

Looks like it's a pretty standard sort of switch - the internals and the spring return will be specially designed for this application but you should be able to obtain a direct replacement.

If you would like to put up a photo of the labels on the switch which hopefully will show a manufacturer (Kraus and Naimer?) and a type number we can probably locate a supplier.

You may even be able to get a replacement from Marcrist as it seems to be their name on the drawing.

Worth spending the money for the right thing - should be £20 - 30 or thereabouts. While you're at it replace the contactor as well at the same time and have done with it. That looks to me like a Siemens contactor (edit - sorry the clue's on the picture it's Eaton if you blow it up big enough - but any similar contactor will do) - should be possible again to buy a direct replacement for about the same again. If you can get a picture of the label on the side of the contactor it will show manufacturer and part number.

HTH Simon

Edited By Simon Williams 3 on 04/03/2020 23:03:26

Good evening again - just a minor clarification.

I'd always assumed that the centre spline was standardised, but looking more closely this isn't right. The 14DP gears I've got have a 6 spline centre but the 16DP gears have an 8 spline centre.

HTH Simon

Drew:

Not sure I can resolve the complications of the screw cutting chart as above, but I might be able to help with a 42 Tooth gear. I say "might" - here's why.

I have a selection of gears squirrelled from various sources, one of which advertised then as suitable for Bantam (which is what I've got). But some are 16DP (which fit correctly and mesh with the originals) and some are 14DP (which don't).

One of these days I'll get a set of 16DP cutters and use the 14DP gears as handy blanks..

In the meanwhile one of these 14 DP gears is 42 teeth. So we need to determine if it will fit with the gears you already have.

Can you measure the outside diameter of one of your gears, and count the number of teeth. It's probably got the number stamped on it, but it's worth checking carefully that someone hasn't done what I'm proposing to do and that you do have the number of teeth specified.

You said, I think, you have a 45T gear. A 45 tooth gear in 14 DP will measure 47/14 = 3.36 ins OD (n + 2 divided by the DP). OD is measured over the tops of the teeth, so it's the diameter of the gear blank.

A 45 T gear in 16 DP will be 2.94 ins OD, so it should be possible to tell the difference.

If the 14 DP gear is of use to you, read on.

That deals with the outside dimension, now to consider the bore. I'm not familiar with the innards of the Mk1 Student, but I'm assuming it uses the Colchester 6 spline drive which others of the marque use. I measure the spline as 6 teeth, 23.00 mm major diameter, 19.75 mm minor diameter.

Gear thickness seems to be a fairly nominal 3/8 inch.

If the 14DP gears are of use to you let me know and we can sort something out via PM.

HTH and best regards Simon

Piece of flexy drive out of a brush cutter? (The kind with a droop snoot instead of a bottom gearbox)

At your local plumbing supplies or builders merchant, buy an aerosol can of pipe freezer. Empty the whole can over the arbour, concentrating on the inboard end.

Promptly (while the arbor is still cold0 give the (loosened) drawbar a sharp rap on the knuckles with a proper hammer. No point at this stage in using a soft faced hammer, it's got serious. Make sure the drawbar is still engaged with the thread in the tail of the arbour -- you don't want to wreck the thread on the end of the drawbar, that just creates another level of complication.

Hit it like you mean it. A club hammer (2 lbs) might be overdoing it, but we're not playing pat-a-cake here.

Hopefully the little blighter will oblige. If not, rinse and repeat.

Good luck

Simon