Here is a list of all the postings Mark Rand has made in our forums. Click on a thread name to jump to the thread.
|Thread: That very light, brown rust / discolouration|
It can be oxidised oil. If it is, a strongly alkaline cleaner may remove it.
|Thread: Air Compressor Warning|
I have an Ingersoll Rand (No relation ) automatic float operated drain system for my compressor. That would really need the drain to be at the bottom of the tank. The other problem with it at the moment, is that it's sitting on a shelf and not yet attached to said compressor!
|Thread: Smart Meters & temperature/BA thread size relationship|
I'm sorry, but that comment is somewhat gonadal.
Rotating kWH meters measure power. Static kWH meters measure power. The accuracy class in use for domestic meters is 2% or better .
And yes, I did spend 7 1/2 years in charge of measuriing electrical power using both types in power station performance tests.
Not only have I had to wipe down my screen and keyboard, but I inhaled a small but significant amount of Green Jack Baltic Trader ale.
Please warn people before making sensible comments in the future.
|Thread: Air Compressor Warning|
Hydro testing is a perfectly acceptable method of air receiver testing.
Air lines, as in Neil's link, are another thing entirely. Works both ways, I've been in a power station where a gate valve was cracked open in an auxiliary cooling water system that had not been filled. Valve and flange left the 18" pipe when the slug of water from the pumps hit it. That was only two bar, but the water was traveling pretty fast when it hit the valve...
Hydro testing as per boiler code is totally appropriate in a club or home capacity.
My opinion only!
As to the original post. I also suspect that the safety valve and the pressure switch failed, rather than the tank failing. Metallurgical examination would be required to show how it could have failed that way at normal operating pressure even with a 20% loss of wall thickness.
Edited By Mark Rand on 24/01/2021 20:27:57
|Thread: Soluble suds disposal|
For such a small quantity, just take it to your local council tip and put it in their motor oil recycling tank. They won't thank you for it, but it works.
For larger quantities, or if you are being good, put it in a black plastic bucket or dustbin, protected from the rain. Fish out any ice that forms in Winter and wait until the summer sun evaporates most of the water, then do as above. A small garden fountain and/or fish tank heater will speed things up a bit.
I've got rid of 30 gallons of the stuff the second way.
|Thread: The demise of UK fossil fuel Power Stations|
Unfortunately, after a while, trees stop absorbing CO2. Then it gets released, along with a certain amount of methane.
Process is known as rotting...
Burning them releases the CO2 they absorbed while growing. So does burning antediluvian ferns, but they can't be regrown...
Eric, you are making the perfect the enemy of the good. The amount of fuel used to transport wood from the US, Canada, Europe and Brazil is tiny in comparoson with the energy content of that wood. That's how transport works.
Secondly, the wood that's used is the trash wood, trimmings, bark, etc. that are a significant by product of the primary wood use.. making trees into sheets, boards, furniture etc. is surprisingly wasteful.
I've only done any work at 8 of the stations on that map, but I would humbly point out that Grain and Littlebrook D power stations on the linked map map were oil fired, not coal fired.
Edited By Mark Rand on 18/01/2021 12:55:54
|Thread: ebay purchases : VAT|
I should have another datum in a week or two. Not worried about VAT and handling charges, but more than a bit miffed that it's easier to order stainless steel toolwrap for heat treating from California than the UK.
|Thread: Standards of Electrical Wiring|
Looks good to me. It's a real pain to have to put a joint in a cable when you do some new work because you did a nice neat job the first time and left no slack for adjustments.
|Thread: Nitrogen as an Energy Store ...|
The Carnot Cycle efficiency of such a system is appaling.
|Thread: Removing powder coating finish from metal.|
Take it to your local powder coating firm. They'll burn it off in their oven.
|Thread: Cleaning Brass?|
Benzine was/is light petroleum spirits. benzene is the nasty stuff.
As a youf I ended up mending my mate's dads "Tickoprint"* Quartz crystal oscillator based watch setting machine.
He used Benzene! Died later from cancer...
*Quartz crystal oscillator with dividers down to a multiple of a watch escapement's ticking speed, driving a rotor with a helical ridge on it like a mower reel. The watch's ticking was picket up by a microphone and amplified to drive a hammer bar towards the rotating cylinder. When the watch was accurate it produced a straight line of dots on a till roll. too fast, the line slopes one way, too slow it slopes the other. The watch/microphone was in a jig that could be rotated to test the watch in different orientations, to mimic wearing. Fault was an OC81 transistor that had died.
|Thread: Which Slideway Oil 68 or 32|
ISO68 oil for most horizontal slideways.
ISO220 for most vertical slideways
ISO32 for rapidly moving slideways, such as surface grinders.
It is only essentially the viscosity that is different.
Those are what I use in my shed.
|Thread: TIG is harder than it looks|
Training is really useful with welding. I managed to get City&Guilds levels 1&2 in TIG and MMA (Stick) at Northampton College. The first because of a redundancy deal, where the company paid for 'retraining' when I took VR from the IT department, The rest from some of the redundancy payout.
4 hours one-on-one for £80 sounds excellent value for money. Even more so if they can start up where you left off if you want to go further.
|Thread: Stent Tool Grinder|
To be fair, I trawled the BSME site and couldn't find peter's grinder.
|Thread: lost drive to power feed|
Strangely enough, my one's got 1/2" silver steel ends, threaded 1/2"BSF, held in with Loctite 603 for similar reasons .
It may be worth putting the feedscrew on a couple of V blocks to check that it is straight. If anyone's tries to lift the mill with slings under the table it might not be. Mine was 1/8 out of true! Straightened to 3 thou TIR with a bit of work.
At this point, it's also worth inspecting the feedscrew nut for wear. unscrewing the outside end of the adjustable nut and having a look down the hole will give you a good idea of how much meat is left on the threads. If they look as clapped out as mine were, you might need to make a new set. Not a particularly complicated job if you have a lathe that can be geared to cut 5 tpi and can grind and ACME bit to sit in a boring bar. If the threads look usable, then just adjust the backlash when you've got it all back together. The one thing that Balding Engineering got very right was to use cast iron nuts on the feedscrews. The nuts wear in preference to the screws unlike certain well known US mills, where the bronze nuts ruin the feedscrews...
A lot of improvements were made on the later Mk2 versions and they've had 60 years for people to abuse them, but when they're all sorted out they're bloody good machines (not biased at all!).
I keep writing without checking or thinking. Sorry!
There should be two T-nuts in the slot at the front, one on the left and one on the right. The two holes that should be in the bottom of the slot just stop the T-nuts being moved past the point where the drive could destroy itself.
With the standard feed on the Mk1 being limited to 4 1/2" per minute, it's useful to be able to set the stops and wander away to do something else. I think that the optional faster feed just used a 2 pole motor instead of the 4 pole one.
After you've got it all fixed, put some permanent stops in the T-slot on the front of the table. There may well be two tapped holes in the T-slot to locate them. That way, the feed will always get cut off before damage can occur.
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