Member postings for Swarf, Mostly!

Hi there, Clive,

Thank you for your encouragement.

Ten-off, well no, but when I do get this one finished I've got a clinometer like Clive's to do. The vial I bought for that has no pip, it's blunt both ends. However, I haven't dismantled it yet so I don't know yet what provisions there are for setting it to zero!

Thanks again and best regards,

Swarf, Mostly!

It's me again!!

Thank you, Clive, for your advice.

I made a trial mix of the plaster of Paris to get a feel for the stuff. I then started the reassembly. Here is a photo of all the parts of the level, including the new vial and the original paper 'pressure pad' :

You can see the two end plugs - not a screw thread or grub-screw in sight!

My first step was to insert the vial and the pressure pad into the inner metal tube and position them as accurately as I could with respect to the window aperture. I then secured the vial temporarily with Sellotape, hoping that it wouldn't pull the coloured filling from the vial graduations when removed later.

Inserting the plaster in the non-pip end was messy but simple. I let that harden for 24 hours. In view of Clive's cautions regarding the pip, I considered and rejected several methods of inserting the plaster in the pip-end. The method I chose was to cut off part of the tip of a disposable plastic pipette (my wife uses them to handle her pond-life microscopy specimens). Here's a photo of a complete pipette and the pruned one I actually used:

I positioned the metal tube and vial, end-up, supported by a quartz halogen desk lamp (it was to hand and saved me the bother of going to the workshop for the retort stand and clamp! ). Then, holding the pipette with its cut end over the vial's pip with one hand and holding the pot of plaster with the other hand, I spooned the plaster into the open end of the metal tube (with the other hand ). I 'broggled' the plaster down into the tube with one of those wooden coffee stirrer sticks. When I thought I'd inserted enough plaster, I applied a couple of lumps of Plasticene to keep the pipette in position until the plaster had set.

The plaster sets in about 20 minutes, I left it for a couple of hours and then fettled the plaster from the rim of the tube end and then removed the pipette. The pipette has raised graduations which the plaster was reluctant to release but perseverance prevailed.

I was eager to see whether I'd adequately protected the pip, here's a photo looking down the open end of the tube, the bright central spot is the pip.

Not the easiest thing to photograph but I think you can see I was fairly successful (except that I've put in too much plaster and it's going to be a b***h to remove the excess) . I have to do that to make room for the end caps.

I'm going to make some sort of a fixture to help press the end caps into the tube with their lugs in line with each other and in correct relation to the window in the tube.

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 26/03/2015 20:01:05

Good morning,

I guess this post is really (but not exclusively) addressed to Clive:

Following my post dated 9th February, I've bought a replacement vial for the Rabone level, together with 750 gms of plaster of Paris.

Having disposed of some other tasks, I'm ready to fit the vial to the inner metal tube. I have two questions:

The vial I have bought has a pip at one end and you (Clive) advised keeping the plaster of Paris clear of the pip - space is kind of short in there and visibility is restricted, please can you offer any tips regarding this aspect of the job? (I did toy with the idea of putting a bit of bicycle valve rubber over the pip but the pip isn't big enough for that.)

I anticipate needing about a teaspoonful of plaster for each end of the vial and would like to minimise waste. Mixing a small quantity seems more tricky than mixing a large amount, do you have any tips for this?

I understand that I need to thoroughly clean the inside of the metal tube as any traces of old plaster will accelerate the setting of the new.

I'll take some photos when I actually start the job.

Thanks and best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 21/03/2015 11:15:55

Hi there, all,

I worry about projects like this one! I'm sure I read somewhere that one of the earlier (1930s?) land speed record attempts failed because the driver attempted to steer the car at speed - the gyroscopic effect resulting from the high RPM of the high moment of inertia wheels caused the yaw moment (steering) to be transposed to a roll axis moment (precession) which turned the car over.

How have more recent attempts addressed this problem?

Best regards,

Swarf, Mostly!

Hi there, Nigel,

Thank you for your post.

The tool-post comprises two parts, a base and an upper block. These (proprietary) parts already exist. The base does indeed have 'a shallow tenon'. It (i.e. the base) is some 48 mm wide so the cross-slide tee-slots will be safely in compression, not bending.

The need for tension in the tee-bolt comes partly from the fact that the upper block is free to rotate on the base, i.e. it is not keyed or latched (like, for example, the 'Duplex' design). The block and base therefore need to be held together firmly to prevent the block rotating out of alignment once set up.

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 11/03/2015 13:59:36

Michael and Jason,

Oops! My mistake!!!!!!!!!!!!!!!!!!!!!!!

Best regards,

Swarf, Mostly!

Hi there, again, all,

Thank you all for your various inputs.

I've decided to take up Jason's suggestion and modify an M10 bolt but only as a temporary measure. (I prefer to keep my ML7 all Imperial as far as possible, just my personal preference.) I'll reduce the head to match the Myford tee-bolt head's shape. This will get the rear tool-post on-line soonest.

The thread I was going to cut on my 3/8" bar is 3/8" Whitworth, a nice deep one.  It's not the top-slide tool-post stud - that's 7/16".  That satisfies Neil's recommendation! (By the way, Neil, surely the tensile strength of stainless is less than that of mild steel??)  I'll screw-cut to rough the thread and then finish to profile with a die (if I can retrieve my box of BSW taps & dies from the workshop gremlins!!)

I haven't yet decided how to attach the tee-slot head to the 3/8" bar. Silver solder seems the favourite at present. And I might not use the EN1a.

Thanks again to all.

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 10/03/2015 22:03:02

Hi there, again, Nick,

I would advise against heat - it's the screws you would need to heat, to make them expand, but any heat you apply will favour the block and make the screws tighter.

It sounds like a job for an impact driver - maybe you should try your local motor-car tyre place? If you do that, though, make sure they have/use a screwdriver bit that really does fit the full widthe of the screw slots.

Best regards,

Swarf, Mostly!

Hi there, all,

I have to make a tee-bolt to hold a rear tool-post on my ML7. It's going to be tweaked-up pretty tight. I had intended to use some 3/8" diameter free-cutting (EN1a??) rod that I have in stock.

Then I remembered that, many, many years ago, during one of the early factory attachment periods of my sandwich course, I was in the trainee model-shop and had graduated to use of their ML7s. On starting one job, I found that the thread on the tool-post stud had stripped (not me, guv, honest!!!) and sought advice from the person in charge.

He had a look and then said 'Follow me.' and led me to the tool-stores (NOT the raw material stores) and asked for 'the KE9'. At least, I think it was KE9 but it was 60-ish years ago! Anyway, it was some very tough stuff.

So, before I could proceed with the routine trainee tasks, I had to perform this extra-curricular job of machining a new tool-post stud. Cutting the thread was a challenge but my efforts met with approval.

Now, here's my question - shall I be wasting my time if I make my tee-bolt from EN1a? Should I look for some tougher (and hence more difficult to machine) grade?

Is this a situation where perfection is the enemy of good enough?

A supplementary question: I've always assumed that the 'KE9' description, or whatever it was, denoted a product from Kaiser Steel, was I right?

Best regards,

Swarf, Mostly!

Hi there, Nick,

It looks from your photo as if there is a hole in the flange under the side of the moving block. If my suspicion is correct, there will be another, symmetrically disposed, on the flange the other side.

I further suspect that those holes are there to give access to screws that hold the keep-plates on the moving block (two each side?). You'd need to move the moving block until you can see each screw in turn through its respective access hole.

Do the screws in the back of the moving block retain the plate on the business end of the moving block?

Best regards,

Swarf, Mostly!

Hi there, John et al.,

Well, further up the page there I made a facetious post. Having returned to the discussion, though, I feel contrite.

This question of storage is a difficult one. I guess for most of John's work he knows in advance what materials he's going to need and orders for the job. Maybe though, he has to over-order to get a better price, relying on repeat work or similar work to use up that excess material in the fullness of time. But, in that intervening period, the material has to go somewhere, to be retrievable and to be safe from corrosion, bending, mistakes of identity and so on. It's far from a trivial matter.

In my workshop, the problem differs in both scale and nature. I don't get through anywhere near as much material as John obviously does. Since I set up my workshop in 1970 (that's three house moves ago!) I've bought very little material but I've accumulated a lot 'in case it comes in handy' (most of it hasn't!). I've got an eight gallon olive oil can with the top cut out and filled with material on end, a large ammo box full of shorter lengths and a box of similar on the floor just inside the workshop door (a trip hazard!) and lots of other stuff in various other places, under the bench, in drawers etc., etc.

The result is that it's physically exhausting and very time consuming to go through it all on the off chance that I'll find that ideal piece inside which my current project is hiding. Not only that but there's just about zero square inches of free horizontal surface in there anywhere. That situation is a great obstacle to achieving results and deriving satisfaction from my hobby.

I know I should have a good tidy and chuck a lot of stuff away but that needs some 'shunting space' as well as time. To those reading this who are just starting out in the hobby, let my situation be a terrible warning!

And, John, please forgive me if my earlier post lowered the quality of the discussion. I hope that you find a solution that works for you.

Best regards,

Swarf, Mostly!

Hi there, Ian,

Well done, the R1000 is a good receiver. I have one that, unfortunately, has developed a fault while in storage. I seem to remember that I found some servicing information on-line, I'll have a look later this afternoon.

I don't use mine nowadays (antenna-phobic planning authorites and land-lords!), besides, I expect there's so much digital IT equipment within range of here (e.g. those ethernet over the mains abominations!!) that the noise floor probably exceeds S9+20!

Best regards,

Swarf, Mostly!

One more from the Department of Daft Ideas:

Belay the "[and adequately drained!]" bit and fill the trench with citric acid.

Best regards,

Swarf, Mostly!

Hi there, Oldmetaller,

Congratulations on your acquisition.

The name of Sissons rang a bell when I read it: there used to be two firms who operated steamers on the River Thames, one was Salters and I can't recall the name of the other. Point is, I'm sure I read somewhere that their steam engines included some by Sissons. Triple expansion rings a bell, too.

I believe, but would welcome correction if I'm wrong, that some of the steamers were converted to diesel but one or more have reverted to steam power?

Looking forward to others pooling their recollections,

Best regards,

Swarf, Mostly!

Gentlemen,

Between 1947 and 1954 I travelled daily by train from Walton-on-Thames to school at Woking. As some of you will know, the railway runs past Brooklands on an embankment, 'affording a delightful prospect'!! At that time, aircraft usually in view were Vikings, Valettas & Varsities.

From that time and into later years, aircraft built there were the Viscount, the Valiant V-bomber and the Vanguard. I believe that the planes were built at Brooklands and then flown over to the airfield at Wisley (see Google Earth) for fitting-out and flight trials. (Correct me if I'm mistaken.)

My parents took the Surrey Herald and, as the first flight of each bigger than the last aircraft got closer, the Herald would write 'residents fearful as flight of monster plane approaches!'. I believe it was for the Vanguard that the runway was lengthened, at the expense of a substantial portion of the motor racing circuit being removed (for ever?!?!). I believe also that there has been building development at the Byfleet end.

One of my favourite stories about Brooklands concerns Billy Cotton, the band-leader. Pre-WW2 he would race at Brooklands meetings but his wife was frightened he might be injured and made him promise to give it up. But the pull of the racing was irresistable and he sneaked off to Brooklands for a race or few. One day the pioneer 405-line TV outside broadcast crew were covering a Brookland meeting and Billy Cotton was named by the commentator. His wife happened to be watching the TV - I understand he got quite a telling-off when he got home!!!

Best regards,

Swarf, Mostly!

Hi there, all,

I'd like to add a caution regarding 'get down to clean metal'.

If you are too gung-ho with the wire brush, what appears to be 'clean metal' appears quite soon. However, this is often an illusion! The 'bristles' of the wire brush are much harder than the mild steel being treated. Thus, the brushing action smears the steel and closes it over the tops of the pits, leaving these largely untouched and still rusty but inaccessible to the Jenolite or other anti-rust treatment. That shiny burnished surface is a snare and a delusion! Those rusty pits will break out again disappointingly soon!

My own preference is to use an abrasive disk and to stop once any loose material has been removed. There needs to be some rust still evident for the Jenolite work on. Also, the instructions on the Jenolite container do not recommend zinc-rich paint as the next stage.  For zinc coating (i.e. galvanising) to work, there must be galvanic (i.e. electrical) contact between the particles of zinc and the steel - nobody has yet expained to me how that requirement can be satisfied when the zinc particles are insulated from the steel and from each other by the binder/carrier components of the paint???

As Phil has posted, what I have written does not apply if the rust is coming right through the thickness of the base material.

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 15/02/2015 15:31:28

Good morning,

A progress report concerning my Rabone Chesterman engineer's level:

I have now removed both the end caps (or plugs), the outer tube, the two end caps (or plugs), two small not-quite-flat leaf springs, sundry glass fragments, a folded strip of paper and several teaspoons full of powdered plaster of Paris from the inner tube.

The end caps (or plugs) were a tight press fit in the inner tube - no threads, no grub screws. Their flanges retained the rotatable outer tube with the two leaf springs providing friction to the outer tube. The springs seat in shallow slots milled in the back of the inner tube, one near each end.

I found no trace of a 'pip' on the wreckage of the vial - if there was one the p-of-P wasn't clear of it! Maybe the vial I've just removed was, itself, a replacement, fitted by an un-tutored repairer?!?!

Plaster of Paris seems to be readily available - I've sought a quote for a replacement vial. (The smelling salts are to hand!)

Pressing in the end caps (or plugs) when the repair is complete promises to be fun - the flanges need to be accurately in line with each other and when I wrote 'tight press fit' I meant it; the metal (chrome-plated brass?) inner tube was flexing!! I hope the mice haven't eaten my tallow ......

I've included the maker's name - other manufacturers' levels will be different.

Best regards,

Swarf, Mostly!

Gentlemen,

Thank you for your inputs. I'll have another go and report back.

As to grub screws, the outer cover tube extends right to the flanges on the end caps - I didn't see any signs of grub screws.

Thanks again and best regards,

Swarf, Mostly!

Hi there, Geoff,

That broken surface in your first photo looks like cast iron to me, not aluminium alloy!

Best regards,

Swarf, Mostly!

Hi there, Michael and Ian,

Thank you for your inputs.

I know about the Plaster of Paris but I haven't reached that yet!

I've got to get one or both of the metal end caps (or plugs) out first!

I need to know how they're attached - threaded, press-fit or what?!?!

Best regards,

Swarf, Mostly!