|Cornish Jack||21/05/2019 16:55:06|
|885 forum posts|
Ask me another on sport ... equally rubbish at that!!
|393 forum posts|
Hardly engineering or model engineering .Made a stainless steel horse shoe for a friends daughters wedding posy..
53 forum posts
Set about modifying a Jag rev counter for the Morgan. I removed the defunct clock from the bottom of the old instrument and made a “medallion” with the JAP logo on the CNC machine to go in its place.
|393 forum posts|
That's nice. When i was a lot , lot younger , and had hair , and a mum , i built a kit car...a Burlington SS , that looked a bit like a Morgan ..and Morgan drivers used to wave at me ,and i didn't ever wave back, as mine was a fake!! Me mum loved going in it , me wife hated it ..I put a 2.5 Triumph engine in it and drove it like an idiot and frightened her ...I gave it away to a school mate .. I'll find a picture...
Edited By Hacksaw on 21/05/2019 18:08:08
|Mark Rand||21/05/2019 19:04:31|
|692 forum posts|
It wasn't what I actually went out to the shed to do today, but I fixed a little niggle on the milling machine. The table feed trip lever is very unbalanced by design and has a tendency to cause the feed to cut out when going from right to left. I finally found a use for a bit of the lump of copper-tungsten alloy that I got off ebay 15 years back:-
|506 forum posts|
The lead pellet weighs about 1.2 grams and would have been travelling at about 220mph on impact, about 8J of energy.
I don't think that your energy calculation is right, Dave.
Working in the more conventional units for airguns in the UK, 1.2 grammes pellet weight equates to 18.52 grains. This seems high for a .22 wadcutter. The pellet you show looks like a H & N Excite (12.82 grains) or RWS Hobby (11.9 grains) ? 220mph equates to 323 feet per second, which is round about what my recently departed Webley Tempest put .22 Hobbies over the chrono at, so seems about right..
However, 11.9 grains at 323fps works out at 2.76 ft pounds energy (3.74 Joules) - quite a bit short of 8 Joules. Even if your pellets are 18.52 grains, that is still only 4.29 ft pounds (5.82 Joules) - closer, but still no cigar. Still, you do seem to be comfortably on the right side of the law for the UK air pistol power limit of 6 ft pounds (approx. 8.13 Joules).
I don't think you should be too suprised that 3.5mm of polycarbonate stopped a pellet - I seem to recall seeing a demonstration on TV some years ago of a 1.5mm polycarbonate visor designed to clip on to a standard UK policemans helmet stopping a full power air pistol pellet at point blank range.
Nigel B (now enjoying a Weihrauch HW40 in .177)
|4318 forum posts|
Oh no Nigel, looks like I messed up again! I admit to not weighing the pellet, I quoted a scribble in my notebook. (From an experiment where I used an Arduino and tin foil to measure muzzle velocity.) And I have a poor record doing sums.
The pellet might be a valuable antique. It's a Milbro Caledonian, possibly bought with the pistol about 50 years ago. Seems like yesterday - how the years fly, scary.
I was pleased with the test. An obvious cost saving on a cheap lathe might be to use ordinary plastic shields, but they fitted the real thing.
Another airgun test I've not seen any figures quoted for is the real-world maximum range a pellet travels. (Not that I've done any research!) Had a notion it could be done by firing pellets at various elevations along a canal and watching for the splash. Quite hard to spot a small pellet landing when it's nearly out of energy I expect. And there's a risk the public won't appreciate my interest is science!
|Martin Rock-Evans||21/05/2019 22:04:05|
|5 forum posts|
Today I cut the final tooth on the final drive gear of my 3" Burrell.
I was really chuffed when it fitted with the drive pinion, right up until when I tried to turn it all the way around and found one tooth that didn't fit! Turns out I missed one on the final pass.
|Nicholas Farr||22/05/2019 07:46:23|
1841 forum posts
Hi, yesterday afternoon I made up a cross brace and welded it on the back end of my stand.
Just need to drill a few holes in the top paint it and fit a draw unit.
|Mark Rand||22/05/2019 13:18:24|
|692 forum posts||
|Neil Wyatt||22/05/2019 22:14:04|
15986 forum posts
The curious thing is that perspex (acrylic) doesn't scratch as easily as polycarbonate.
This makes acrylic a good choice if you just want to stop swarf getting out and hands getting in as its working life is longer.
Polycarbonate is best if flying chuck keys are a risk in your workshop.
|369 forum posts|
Set the dividing head on packings to allow a 9" disc, mounted on a face plate to be gear cut .Only a segment of the disc was required as I need a curved rack,a result.Now for the pinion.
|Nicholas Farr||25/05/2019 09:45:25|
1841 forum posts
Hi, yesterday with the absent of a Mag-drill, I resorted to an old tech solution. Bit more fiddly to get lined up on the centre pop, but it worked very well.
|paul rayner||25/05/2019 18:50:40|
|109 forum posts|
went to castle Howard today and saw this unusual steam waggon. i've never seen one before seemingly the owner says theres only about a dozen left.
|Rik Shaw||25/05/2019 19:06:20|
1278 forum posts
Repaired the cast iron axle on the village white lining machine. Together with new plastic goal posts the chillun will now be able to play footy with white lines on their pitch instead of having to use bollards and jumpers for goal posts.
|Neil Wyatt||25/05/2019 19:40:10|
15986 forum posts
Yesterday I picked up a 'new' combo amplifier, a bit of a classic
Today I added the external speaker sockets missing from the combo version so I could use it with an extra cab and tweeters.
I don't think it can stay in my workshop though...
|Nicholas Farr||26/05/2019 08:34:46|
1841 forum posts
Hi Neil, nice piece of kit. What size are the units in the combo and power rating?
|Danny M2Z||26/05/2019 10:25:55|
732 forum posts
Today I heard that (in the U.K.) the end of May is going to be a week later than it's usual date
(I was born in Mile End Hospital so qualified to comment)
* Danny M *
|1274 forum posts|
😀😃 Yes from all the headlines I gather it will finish on 7th June this year.
Edited By V8Eng on 26/05/2019 10:54:31
|3069 forum posts|
Trouble is May never really started at all. A lost month or is it years?
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