Here is a list of all the postings Glyn Davies has made in our forums. Click on a thread name to jump to the thread.
|Thread: Bending 1/8" Steel Plate|
This is the similar handle I made and it is very useful if you don't have a VFD with jog function. I use it for thread cutting with taps and dies and also screwcutting. Even used it to true up the lathe motor drive pulley!
However, if you start the lathe with it still fitted and it whacks your elbow, it don't half hurt. So make it a habit to disconnect the back gear, turn the reversing switch to off and turn off the main power when you fit it.
|Thread: Annealing stainless steel|
Who said it was cheap?
Just to wrap up. I used a hacksaw to cut out a rectangle from the 3mm plate, heated it to red on fire bricks and quenched. Result - no softening. I then reheated it and let it cool naturally. Result - no softening. So then it was a couple of hours with the angle grinder with a 1mm cutting disk, disk sander and files and voila - job done. I put it in the 4 jaw in the lathe to drill and bore the 25mm hole. But no more stainless for me, thank you!
Thanks Neil. I've ordered one of the ebay straps but the tongue part comes with a slot and I want a ring. And if I don't have a go at making it, that square of stainless will just sit their until I've shuffled off..
This was prompted, by the way, by Cheshire Police announcing that any drivers caught with unrestrained dogs will get done for driving without due care. Despite the fact that our Stanley sits happily behind the rear seats of the Focus either looking out of the back window or dozing on his bed.
Thanks for the replies. This is what I want to make (a means of attaching the dog to a seat belt socket!):
I think I'll cut a rectangle out with an angle grinder and put it on the gas ring for a while, quench and see how it cuts with a saw. The square of 3mm plate I bought from the autojumble had been cut with a press brake, so it's obviously cuttable with HSS.
As an aside, I am surprised to find that my Draftsight is still working - they said unless I paid a subscription it would be gone by Christmas.
Edited By Glyn Davies on 27/02/2020 22:39:59
I have some 3mm thick stainless steel that I bought from an autojumble. It is non magnetic. I need to saw, drill and file it into a large key shape. Is there any way to anneal it so it won't wreck my bandsaw blade?
|Thread: Bicycle pedals|
I recently removed the pedals from my bike to make it easier to load into the back of the car. I was surprised to find that the right hand pedal has a right hand thread where it screws into the crank and the left hand a left hand thread. And this seems to be common across all bikes.
How could the cycle industry have made such a fundamental blunder? It clearly should be the other way around so that any friction drag in the pedal bearings will tend to tighten the pedals in the crank rather than loosen them.
Should I start a campaign?
|Thread: Slip gauges|
I found limited use for slip gauges until I came across an accessory set at a car boot similar to this one that is on ebay:
I now use them a lot - it's so easy to make up various configurations of go-nogo gauges for jobs where it's difficult to get a mic or caliper into.
|Thread: Does anybody know what this is ?|
A Victorian electric shock therapy machine with bits missing to make it safe?
|Thread: Electric Cars|
I read that the grand master plan is to equip all houses with some kind of ground or air sourced heat pumps for heating/cooling. Then use smart meters to draw power from all the electric car batteries that will be plugged in for when the wind doesn't blow or the sun shine.
I think gas heating is banned for new build houses within the next couple of years.
I just wondered if anybody else was mildly depressed about the prospect of having to switch to a Battery Electric Vehicle, or electric car, at some point in the not too distant future?
The energy content of petrol is about 10kW-h per litre, so a full tank, weighing 35kg, gives about 500kW-h – compare that with the 30 odd kW-h and 300+kg in a Nissan Leaf battery. I know a petrol engine is down to about 20% efficiency against 90%+ for electric motors, but our ecoboost Fords get twice the mpg of the old Cortinas of old, so maybe the 20% figure is now pessimistic. But with only a couple of litres left in the tank, I can still squirt from 50 to 70 mph as quickly as ever.
Leeds City Council has just declared a “Climate Emergency”, whatever that is, so the swing to electric is obviously here. But the idea of having to keep a constant eye on the charge level, of probably not being able to keep up with traffic as the charge depletes or the battery ages, of having to plug the blasted thing in to a socket every night, of having 320 volts ready to connect to the body shell in the event of the slightest accident – I’m really not keen.
I just think there has to be a better way. Power lines in the road with contactless connection to the car? With a small battery to cope with ‘off piste’ excursions? I’m sure that if IKB was still around, he’d come up with something better than the BEV. What do you think?
|Thread: Stuart No. 1 Build Progress|
I find the way to happiness with a four jaw chuck is to use two chuck keys. Tighten one whilst slackening the other. I made a second key for my 6 inch four jaw chuck that was small enough to use at the motor side of the chuck.
|Thread: Free cutting mild steel|
Thanks for the replies - I'll grind a right hand knife tool with 55 degrees top rake and give it a go with whatever EN1a steel I find.
I think a 100 thou depth of cut is going to make it chug a bit though!
I want to make some grinding wheel adapters for my universal cutter grinder, which involves a lot of turning 50mm bar down to 20mm. Much of the BMS I've bought in the past does not really turn well using HSS tools on my little Myford so I'd like to get some mild steel that is truly free cutting.
Should I be asking for EN1a Leaded as being the free-est cutting BMS that money can buy?
|Thread: 1959 Nsu quickly|
Me and my sister on dad's NSU (photo dated 12th June 1960)
Edited By Glyn Davies on 03/05/2019 11:51:49
|Thread: Using a propane cylinder for partable compressed air.|
Many thanks to all those that troubled to reply!
I’ve just been examining the cylinder for any information marked on it. It is dated 1978 and a plumber gave it to me; there is no gas company mark on it, so I’m going to class it as mine!
It is marked TP 33.2 bar (481psi), SP 30.9 bar (448psi) and WC 9.2l. I assume SP is the Safe Pressure? The fact that propane molecules seem to embed themselves in the internal surface of the cylinder and then eke out over time did worry me a bit (the air coming out does smell a bit of propane, or whatever they add to propane to make it smell) and I see that the lower flammability limit for propane is just over 2% by volume at 150psi. That means that there needs to be 184cc of propane in the 9.2 litre cylinder when I fill it for there to be a combustible mixture and I just can’t see that much propane detaching itself from the steel interior. On the matter of condensation, I wonder if all the free water in the air will have condensed when it was first compressed by my shop compressor; I inverted the propane tank and opened its valve and no water came out.
I fully understand the views of those replies that urge caution (or cessation!), but having seen the test pressure value and lower flammability level of propane at high pressure, I’m fairly reassured that it won’t go bang. I think I’d be very wary of pressurising the 50 litre receiver of my Clarke compressor to 480psi, particularly after having regularly drained very rusty water from its drain tap over the years.
I visited the US back in the 90s and saw some portable compressed air tanks for sale in Walmart. Never seen them here and often thought how useful one would be around the car and home. Anyway, I recently acquired an empty 3.9kg propane cylinder and thought I’d try it. It works a treat. When filled with compressed air at 150psi I can top up eight car tyres with ease before it empties. My question – can anyone see any safety issues with this that I’ve missed? I thoroughly purged any remaining propane from the tank before I filled it with compressed air and I see that the vapour pressure of propane is 150psi at 32 deg C, so the tank must be designed for this level of pressure. I tried unscrewing the valve on the tank so I could fill it with water and proof pressure test it to say 300psi, but the valve is too tight to unscrew.
|Thread: broken calipers|
I would turn and file it from solid silver steel bar, hardened and tempered to blue.
I did a search on cheap calipers to see how much it would cost to buy one for the spring and came across this one from RS:
I'm not sure why it's listed as being metric!
|Thread: DraftSight no longer free|
Just opened mine and cannot see a message - is it hidden somewhere?
|Thread: AutoCAD substitute|
Just in conclusion - the more I play with Draftsight the more capability I find. Things like spline, rotate reference, scale reference, fillet are all there, just not on the main ribbon. So thanks again for the suggestion - life is good once more!
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