Member postings for Clive Hartland

How about one of those plumbers flexible blankets they place around and under pipes when they are soldering pipes in the house?

 

Clive

Hi Mick, yes, I had to relieve all the axle boxes as there are five axles and as they flex up and down all the cranks have an effect anyway.

I read one item about the cranks and connecting rods and this was that play in a full size loco was 60thou.

As the axles tilt the clearance gets less and I would think that the movement is quite small

So I took all this into account and allowed some extra clearance between the axle boxes.

I can press down on the chassi and rock it side to side and move along at the same time.

I have no binding of moving parts at all.

I did find a mistake on the drwgs. about the size of a link , I would have to look back at this to remember.

 

Clive

Neil, you have double flanged axleboxes like my Evening Star, I had to relieve the flanges in an arc so that as the axle was lifted one side it stayed free to turn.

Hard to describe but a few minutes with a file relieved at both ends of the flanges solved the binding problem.

The axle lift is very small and not very much metal has to be removed.

 

Clive

That is not an unusual disintegration of a bearing, I have had several small bearings where the flash welding on the cage has let go.

One time it was the main bearing in an Ariel 350 M/c.

Larger bearings have rivet cages so are better.

I did not like the look of the two ball bearings shown!

Once the cage goes then the balls lump together and disaster.

The answer is replace with decent quality bearings from a known source and keep spares handy.

 

Clive

One thing Wolfie is that make sure that you have enough heat output from your heat source.

For the small eyelet you have mentioned one of those small gas canister lamps will do but if you need to braze/silver solder a large piece of metal then you will need a much larger gas torch.

 

Clive

Yes to the De-humidifier, it will take gallons of water out of the air and you will have to ensure you empty the bucket regularly.

In one instance a humidifier was used to keep a computer room dry and there were about 200 packets of printing paper in there as well and we were emptying the bucket twice a day until the paper dried out.

That was roughly 2gall. per day!

I would not cover that machines in cloth, plastic draped over perhaps, but keep them oiled.

Me, I'm lucky as my garage/workshop has a radiator connected to the domestic system and it is perfectly warm and dry.

 

Clive

The emitter of a diode laser is half moon shaped and when projected gives a lozenge shaped point of light.

They need a focusing arrangement and we set them to rotate about one end of the lozenge image. Our lasers can be rotated so it is easy to determine where the laser is pointing.

Please bear in mind that looking into a laser is bad for your eyes and over a prolonged time can leave permanent laser burns on the retina.

 

The power of the laser is the governing factor and I doubt anyone is going to use a laser of 1Mw or I hope not!

 

Clive 

A much better system is an optical telescope with a X graticule. With an inbuilt prism they can be looked through at right angles to the target.

They are very easy to adjust/check by rotating 180deg.

Lases are much better suited to long distant sighting, like 20/30 mtrs.

If you go to an auction/sale and see a Tribrach with an optical plumb attached then that optical plumb will sight down to .5mtr.

I have already modified one for my own use.

They can be modified quite easily and attached to a M2 taper for use in a tailstock.

Remember to clamp your tailstock if you use one, as a loose tailstock will not align correctly.

 

Clive

Its Chinese Wolfie, of course they are plastic gears.

Everything I have picked up this Xmas has been made in china!

One of the modifications is to replace with metal gears as quoted earlier.

I think there is also a mod. using a toothed belt and cogs.

This is why it pays to research your choice of machine when buying.

 

Clive

Christopher, the high speed machines are offered with X,Y,Z drives and can be used for engraving.

They can also be used manually.

Engraving cutters need high revs to cut efficiently.

I would suggest asking them for a catalogue which explains the various set ups with these machines.

By the way, I suggest you buy one with a long table, the 1200 series is a very short table length.

Otherwise they seem to be very good machines and far better mechanicly and technically than some of the Oriental offerings.

I agree the prices are on the high side but they recently reduced the prices by about £239 on one of them.

 

Clive

Hi Michael,

the only one I have come across was a large cement pedestal that was used as a base for a long distance measuring line, it had a prism that ran along a track over the heads of all the workers and equipment.On advice it was sunk down about a mtr or so but had deeper blocks at each corner.the reason given was that the ground was unstable and the extra pads would stop it moving out of the vertical as we measured to less than a 1/100 of a mm. It was quite an expensive job but we never had a problem.Later the adjoining building had its foundations washed away as it was built on alluvial soil deposited by Glaciers and had 20000tons of soil packed into it to stabilise it.There are a lot of problems with soil stability, particularly as they are now rebuilding over old ground. They have to stabilize the ground by freezing it and then build the casements and they then hold back the soil shift. An example is the light railway and road going into the Dome in London. It started to move so they inserted long rods and froze the ground until they had completed the supports for the rest of it.When you shift thousands of tons of soils something has to move and they monitor all the workings continuously with prisms or reflectors mounted on the construction.This is big business for our company as we supply certified measuring equipment.

Clive

 

Interesting point about the machine bases, some years back we investigated a complaint that our most accurate optical level was inaccurate and unstable!

We carried out tests in our workshop and could find nothing wrong with the level.

Investigation was then transferred to the site of operation which was an assembly jig for a helicopter body.

Arriving in the morning we set up everything and started monitoring as they worked, it seemed the errors were intermittant so we had a long day ahead of us.

We adjourned for dinner and when we returned all the readings were haywire and the jig was out of alignment, every setting was checked again and then we realized that the site was on the bank of a creek and looking out the window showed the tide was in.

The water pushed the sub soil and caused it to heave and later we found out the site was on re-claimed land.

The jig was moved to another location and no more trouble was found.

The intermittant errors were the tide time errors!

 

The second one was a large concrete plinth that had four wings. It was some 16cub/Mtr of concrete and some 2mtr. deep and after initial drying out we set up the collimators and adjusted them for accuracy.

This was for a specific to task set up for a special sight for use on a Howitzer.

The objective glass was a sphere and had to be glued and clamped exactly.

We had continuous problems with stability until we realized that heavy tanks going past were disturbing the concrete plinth enough to cause severe bubble displacement!

There was no answer except to re-route heavy vehicles another way.

 

Clive

 

In all my time as an Instrument tech ( 60 years now) I have never heard of that!

Instruments with liquid bubbles have always been stored horizontal apart from some Cooke Troughten and Simms and a couple of Hilger and watts levels in metal cases.

All others only have a storage attitude because of the design of the case they are in.

 

Clive

A lot of Vial tubes are used in two positions,standard level and inverted!

There are 'Turn over level's used for drainage layout and Optical plumbs are sometimes inverted for Nadir setting.

Honing the Vial tube depends on the sensitivity you require. The shallower the arc the faster the bubble will travel and the more sensitive it is.

There is the fact that a commercial Vial will be accurate whereas a home made one will be literally any reading!

I think I would rather buy one of a known sensitivity.

 

Clive

The glass vials/tube are honed out internaly by very experinced workers.

I seem to remember that the radius of curvature of the inside of the tube is some 60ft.

Tubes are filled with various mixtures but usually Ether or a mixture to slow the bubble down a bit.

The tubes come in various 'Speeds' from 10" onwards. Illumination is sometimes made using Tritium tubes under the vial.

There is a move now to composite bubbles where two metal ends are glued to the tube and it is filled through a small hole in one of the metal ends and then plugged and sealed.

The ends have a propensity to snap off at the glue joint. The mounting points being the metal ends.

If you are making a spirit level for use in the workshop there is no need to have a full length contact of the base.

Two bearing surfaces of an inch or so at the ends and the center portion relieved about a

sixteenth of an inch.

 

Clive

It is now standard procedure to send optical levels and other levelling devices to an Instrument Workshop for calibration before they are used for survey or industrial measurement or building work.

Most of my work load is calibration and certifying that the instrument meets the manufacturers specification.

An example of cost for calibrating an Electronic Total station is about £500. If repairs are needed then that is in addition.

A small 8sec. optical level is about £45 for calibration.

We have to have extensive test equipment totaling many thousands of pounds and to have PC's with the software to read the Electronic programming in the instruments.

In our workshop we have five people and all of us have at least 25 years experience in instrument repair and all its ancillary requirements.

Then, our test equipment has to be sent for calibration as well. Dvm's and Frequency meters and Temp. gauges plus all our torque wrenches and dial gauges.

We also have an annual inspection from the main importer of the instruments we repair.

Looking at the cost, this is based on the time to do the calibration procedure.

 

Clive

I am in my ninth year of constructing a 3.5" Evening Star, This time period partly due to

lack of facilities when moving houses.

The build is interesting and as a 2-10-0 can get a bit long winded making multiple parts. Luckily i have only had to remake 1 part as the drawings are wrong.

I now have a rolling chassi with the Tender complete, the smoke box is done.

Then the change in requirements for boilers came along and now I have to find £1300 to have a boiler made, where previously it would have been about £300.

see my Photos for the Loco so far.

As to which gauge to build I cannot say as I am committed to the one I am doing.

I even have the Evening star in 00 gauge just to look at.

 

Clive

0.1 deg is 6minutes which is a big error to me.

I am used to working to within 1 or 2 Sec.

Bear in mind that the tolerances give a big margin for error on bubbles with a graduated scale.

If you set up a lathe bed then you have to, 'End for End' the bubble.

This means you level in one position and then turn the plate level 180deg. and take half the error shown out of the bubble adjustment and half out of the bed adjustment.

You have to do this slowly to allow the bubble to settle and do not touch the bubble or mount with your fingers and do not breathe on the bubble, if you do the bubble will run and give a false reading.

'Never trust a bubble', Always check and then re-check.

After this sequence you can safely continue the check of the bed level.

The bubble should indicate its tolerance. ie. 20" or such, again bear in mind you are leveling a bed and the tol. is not required for that purpose.

 

For accuracy then the best method is Auto Collimation where the bed is checked every 300 mm and a graph drawn showing deviation of the bed.

This requires a theodolite with an auto-collimation eyepiece and a surface silvered mirror in an adjustable mount which is traveled along the bed and readings taken.

Readings are twice the error. Incident ray/reflected ray is twice the angle.

To me this would be the only method on a long bed machine.

 

Clive

The way chemicals get into the human system and the effects apart from death are interesting.

When I was in kenya we often visited the taxidermist works, the name was Zimmermans.

A nicer chap you have never met, he took a shine to my wife and took us around to see the processes being carried out and also gave my wife a piece of Leopard fur to keep.

While talking he said that the cyanide had got into his system and showed us his hair which had turned green!

He had been exposed to it for years. He said if a snake bit him it would die first.

The store shed reeked of strong chemical and I could not go in without choking and coughing.

 

Clive

I spent 6 months in a plating shop as part of my army apprenticeship.

cadmium plating is now not used commercially but is still used on aircraft components.

The passivation will turn it a goldy yellow colour.

Mainly we plated the links and hammer bars on Creed Teleprinters with it.

It has a pleasant colour to look at but as said it is deadly over time.

 

Clive