Here is a list of all the postings norm norton has made in our forums. Click on a thread name to jump to the thread.
|Thread: Dam Solution?|
quote above : "The Victorian construction of the dam appears to be perfectly sound. It's well over a century old and even with the failure of the spillway it's remained functioning despite taking some very serious damage."
The above is something I agree with, although I am not a dam or construction expert and I have only seen the broadcast pictures. Local residents are saying things like "we were saved from an imminent collapse". Who ever thought it was about to give way? There were no reports of water penetration, which normally precedes a collapse.
Certainly any consulted engineer would have to report that its condition was weaker than before the overspill, and that it might give way if more water came over the top and removed a substantial amount of the soil wall. I suspect that liability and risk management then took over and the various agencies all stated that it was in danger of imminent collapse with the need for evacuation.
It will be interesting if any reports appear from any construction expert regarding how much soil wall had been removed and how much weaker it then was, with the full head of water behind it.
|Thread: Timesaver - which grades?|
There is/was a small 'sample or trial' kit of eight little tubs (2" dia. x 2" high) that I bought a few years ago.
|Thread: Sealing Threads|
Search for Rocol Steam Seal which is designed for this very job. Suppliers on eBay, and Heritage Steam are a good company.
|Thread: Piston Packing|
The packing needs to just standing a 'bit' proud, but it will be all over the place with high spots and hollows. Once it is in the bore it should even itself out. Yes you want to be able to 'just' pull and push the piston gripping the piston rod. It will be tight so oil it.
Make a conical adapter (5-10 deg internal taper) that you feed the piston and packing into, then line that up with the cylinder bore to easily slide in. The inside bore of the adapter exit should be the same as the cylinder bore. The taper helps squeeze it all into shape.
|Thread: print-offable and laminatable chart|
Very rude of us John to find humour in your fine feed numbers and I apologise for starting it. What you have listed is a perfectly logical way of showing the fineness of feed.
But I like that idea that at 569 TPI my Myford Series Seven might do better than the 'world's finest known thread' of 508 TPI. I might have a try, should I sharpen the 60 degree Whitworth tool first?
|Thread: Displacement lubricator - with or without valve ?|
Yes we all agree that the steam condenses in the lubricator vessel and it is this that displaces the oil. My apologies if I misled by not saying that I agreed with this basic principle at the start.
Our discussion is whether this Simple Displacement Lubricator might be a continuous system or a cyclic one. This lubricator uses the same entrance and exit to the steam line, or steam chest as fitted by Stuart. I suggest that the flow direction must cycle. An experiment would be simple to do - just connect a steam line to it and leave it under pressure, and see if it gradually fills with water and all the oil transfers to the steam line.
There is another configuration sometimes called the Hydrostatic or Ramsbottom style that has a steam inlet, typically from the regulator supply, to the displacement vessel and a separate oil outlet to the cylinders. These do not need to cycle and are effectively continuous. They were developed for use on full size steam locomotives and even included sight glasses to observe the dripping oil flow. If configured to take some steam directly from the boiler they would then operate continuously. They are still used on some model locomotives, especially GWR variants.
Every respect Duncan, but your version makes less sense. You suggest that steam keeps flowing through the pipe, and any small jet or valve, at the same time as oil flows the other way? Which end of the pipe has the higher pressure? A cyclic system however will follow the inevitable pressure changes in the steam supply. A small bubble of air is necessary to allow that cycle to execute and balance the pressure in the reservoir to that in the steam line.
|Thread: print-offable and laminatable chart|
I love the last line in the chart showing what you need for 569 TPI (!!!) Can't think of an immediate use for that..
Out of interest, what is the finest thread used on a practical object that is known of?
|Thread: Displacement lubricator - with or without valve ?|
The steam enters the oil chamber and condenses only when there has been a change in pressure, i.e. you start the engine. Then when the pressure drops some oil will be expelled into the steam line. If running at constant speed there will be no additional oil introduced. The volume of oil displaced each cycle also depends on the amount of (compressible) air in the reservoir at the start.
It just needs a reasonable one inch or more of small bore tube to tee off the steam line and possibly a jet of 0.010" or 0.020" in the line if it does empty the oil too quickly.
|Thread: Drilling Small holes in Gunmetal|
Well said Russell. I completely forgot that. I use the same all the time - essential on the taps.
For small drills of this size I have never found that adding anything wet helps. Lubricant starts to work when things are getting hot.
As Jason has said, once the hole is drilled then use the chuck to help line up the tap. For 10 BA and smaller grip the tap with a small Pin Vice, not a Tee Holder, and just use finger and thumb to rotate and sense the resistance. Don't grip the Pin Vice in the chuck, just use a pointed rod to visually align things. One finger on top of the Pin Vice to get it to bite and descend. Take it out every turn and brush off the swarf.
For bigger jobs a spring centering tool can be held in the chuck, but I don't find one helpful with tiny taps, and the tops don't have locating holes anyway. If you have not got a Pin Vice then look for some genuine used Eclipse ones on eBay. Don't buy cheapie £10 new sets as they won't grip and will be off-centre.
It is essential to have sharp drills for bronze with no lip wear whatsoever, or they will drill undersize and then bind.
Best to buy new ones for the job and get a decent quality brand. Cheap ones will jamb. This link is a good ME supplier and is happy to post just a few drills. **LINK**
Have you got a nice small chuck to fit the mill? Best not to use silly high speeds, just 600-800 RPM keeps it controllable. Feed down slowly, just fast enough to produce a slow output of swarf. Apply a spindle brake slightly to stop it descending under its own weight. Lift the drill out every 1-2mm to clear the swarf.
|Thread: Myford 33t and 34t gears for metric threads|
Hmm.. the electronic lead screw will have to be exactly synchronised with the main spindle rotation.
A google search for Myford 33T, Myford 34T comes up with lots of links.
Read this past thread for more information as well
Edited to add that the John Stevenson mentioned in that thread is now no longer with us. But the gears are now made by others.
Edited By norm norton on 27/01/2019 09:58:32
Edited By norm norton on 27/01/2019 10:00:52
|Thread: Piston rings|
The o-ring will wear a flat face very quickly. It will work for several hours until it does.
Ideally you want to fit cast iron split rings and I appreciate these can be tricky to make. I have just made a set and If you want help then message me. If your bores are accurate to diameter then you can buy rings from someone like Reeves, but they are about £13 each.
An alternative is split PTFE rings riding on top of o-rings. But this is as tricky to make as cast iron rings IMHO.
If you pack with a PTFE/graphite square material it will work fine for a few years, but be prepared to replace it one day. Not the end of the world and the quickest solution.
|Thread: what solvent cleaner to use?|
Inhibisol TF90 contains the following, according to the manufacturer's MSDS sheet:
Hydrocarbons, C7, n-alkanes,isoalkanes, cyclic propan-2-ol; isopropyl alcohol ;isopropanol
I would regard that as a reasonable set of solvents to use.
Its good to warn people if something is a problem, but the Brake Cleaner + TIG link does not sound right.
The Brake Cleaner we can get from motor factors in 5l containers is a mix of methyl acetate, hydrocarbons like petroleum spirit and around 50% acetone. It is formulated to be moderately 'safe' in use and contains no chlorinated solvents.
To make phosgene COCl2 you need a chlorinated solvent and heat. That link to the USA page shows an aerosol can of tetrachloroethylene, which is as bad for the environment as all other chlorinated solvents. I guess it is labelled as "for cleaning your brakes"?
I use conventional Brake Cleaner a lot.
Edited By norm norton on 07/01/2019 20:58:25
|Thread: Selecting a VFD for a Harrison lathe.|
The 140 is a lovely lathe - well done getting it. I hope you have got the tailstock as well and the big 4-jaw chuck that the school might have had. The 140 was Harrison's later, metric version of the LS5.
I fitted a metric shaft 1.5kw 240c 3 phase motor to mine. I just cannot remember if I had to modify the pulley bore. I have feeling it went straight on the new motor. The motor fitted the existing lathe frame with just some 2" sleeves and longer bolts to raise the motor. This all suggests that Harrison had fitted a modern spec motor. Measure your existing motor's shaft diameter.
I went to Newton Tesla and bought the motor, Mitsubishi VFD and a dongle controller together. It will cost you bit more than shopping around on eBay but you will have a nice system with start/stop, forward/reverse, jog/run and speed all on the controller in front of you. If budget is an issue then go it alone but you need to be confident in your abilities in programming and handling hefty voltage wiring. You MUST NOT start/stop the motor by breaking the supply into or out of the VFD. Wire the VFD directly to the motor and do not use any of the Harrison control switches.
I actually fitted a 2-pole motor (rather that the usual 4-pole) as it gives me the possibility of double the usual lathe speed. The 140s were built for it and you can get front plates that show the doubled gearbox RPM. To be honest I rarely use the higher speed, but I do run the lathe a half motor speed most all of the time and it is much quieter. The motor is perfectly happy for the usual light and moderate load jobs.
You can get some extra change wheels and will be able to cut all the imperial threads directly from that metric gearbox.
Edited By norm norton on 10/11/2018 11:22:31
|Thread: Running coal fired 5 steam engine on gas|
As has been said above, without seriously big burners, and a large bottle of propane, you will struggle to get enough heat into the boiler to produce useful steam.
A "Steam Test" for official purposes requires a full coal fire, with full blower, to check that the safety valves can release all the steam produced.
If you want to test your boiler for minor leaks and is the pipework ok, etc. then make up a water hand pump, valves and gauge and then hydraulically test at the boiler's normal working pressure.
If you want to test the cylinders and running motion then get a compressor that can shift at least 4 cufm.
|Thread: X3 mill spindle tightness|
There is a small pin that locates in the R8 tool groove. Just check it is not possible to push that pin through the spindle and into something and cause drag. I cannot recall exactly the geometry, but I had a problem with mine and stripped the spindle to fit a new pin that I made.
Some tooling has grooves that are too shallow and I have had to hand (diamond rotary) grind these to be a few thou deeper.
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