6324 forum posts
Exeter & District Model Engineering Society has enough of its new track laid to do public running on it for the first time today. From now on it will be possible every first Sunday of the month but there is an extra day on the 19th Sept as it is the open day for the model railway club who also live at the St Katherine's Priory community centre in Stoke Hill Exeter.
There was good support from the local children wanting rides so a great start to our operations at the tracksite. Well done all those who have been working hard to build the track under the restrictions of the last year. Still more to do if anyone finds themselves at a loose end on a Tuesday.
|duncan webster||07/09/2021 16:27:10|
|3984 forum posts|
Well I contacted the manufacturer, who claim that all their showers are tested before shipping. Either they missed this one or they don't check for shorts. They also deny any responsibility for consequential damage, which conflicts with my understanding of the law. They seem to think their reputation isn't worth the £8 I was claiming, so no need to be coy, I won't be buying from Triton again, and would advise anyone else to avoid them.
Edited By duncan webster on 07/09/2021 16:28:15
|Derek Lane||07/09/2021 20:03:19|
759 forum posts
Still working on the new workshop nearly finished the major work except the electrics. At least I will be able to start moving back in soon
|Andrew Johnston||10/09/2021 12:44:48|
6601 forum posts
Finally got around to machining the underside of the flanges on my traction engine cylinders:
The piece of steel sheet against the angle plate is to tilt the cylinder slightly so that the vertical centreline of the pistons lines up with the crankshaft. In the CAD model the angle is 0.64°, but I settled for anywhere between 0.6° and 0.7° on the digital angle gauge. The backward tilt of the cylinder mimics that of the full size engines, where the designer presumably ran into the same problem of things not lining up.
Roughing cuts were 40 to 50 thou deep and 10 to 15 thou feed per rev at 54rpm. On the finish cut feed was reduced to 4 thou per rev, which took for ever feeding by hand.
Fortunately when mounted on the engines both cylinders slope back by 0.6° indicated and the measured distance from flange to top of the cylinders is within a couple of thou of the CAD model value of 8.07". So there's no excuse for everything not lining up.
6324 forum posts
EDMES had it's delayed AGM today and just managed to get a forum of 15 members to comply with the constitution and elect a new Chairman ( who is in Corfu at the moment).
Good that people are getting back into the groove
|Nicholas Farr||12/09/2021 14:38:45|
3360 forum posts
Hi, yesterday afternoon I set about up-cycling some scrap pieces of metal to make a step-up, which is about 230mm high, the tread is a chequered aluminium stair tread, which I made a couple of flat pieces of 40 x 6mm flat black bar and drilled a couple of holes in each end to match the holes that originally fix the tread into place and 10mm nuts were welded onto one side of these plates where the holes were drilled. Four legs are from some tables that had castors attached, of which I had to shorten down in my last day job and these where much to useful to bung in the scrape bin, so I acquired consent to take them home. (I think there were about eight tables that I had to alter, giving me 32 of these legs some of which I've used for a couple of other jobs)
Two legs were set-up at one end of each of the plates and piece of 20 x 20 x 2mm SHS was cut to fit between the two as a tie-bar and was also set-up. These were then all tack-welded into place.
The other two legs and another piece of SHS were then set-up in the same manner and tack-welded into place and then two shorter pieces of SHS were cut and set-up and tack-welded into place between front and back legs. All four of these legs were picked from the selection that I have, so that my tie-bars could be weld in the same place as the tie-bars were on the original tables.
Hoping the weather is OK tomorrow, I can then weld all the joints up and then look to see if I can reverse the up-turn of the tread to a down-turn to match the one which can be seen at the front in the above photo.
Edited By Nicholas Farr on 12/09/2021 14:44:36
1300 forum posts
I can’t find a specific forum for this, but today I visited Wortley Top Forge, just north of Sheffield. It’s only a 15 minute drive for us. I went many many years ago, but it never really registered in my memory as a child. However, a work colleague went recently, and told me it was good.
|Nigel Graham 2||13/09/2021 00:00:59|
|2132 forum posts|
Thank you for the photos etc of Wortly Top Forge , Bazyle. That lathe has some very fresh-looking swarf in the buicket under it!
I do like these smaller, volunteer-run industrial museums as they lack the pickled-in-aspic-and-ignorance feel of one or two of the Big-Name places I have seen.
If you are Down South, in Somerset, Weston Zoyland Pumping Station Trust's work is worth seeing - and it does run its engines on steam, supplied by a large Portable Engine uinder an adjacent lean-to. Pride of place is its original, in-situ, Amos engine and centrifugal pump. The site was originally for fen-land drainage, on the Somerset Levels; and the modern pumping-station (not publicly accessible) is adjacent to the museum.
Though only open occasionally, there is an intriguing small-scale water-works museum just outside Sherborne (N. Dorset). The water-supply pumps were water-wheel powered and have been partially rebuilt to show this; but the museum also has a fine Hindley mill-engine rescued from another water pumping-station in the area, and run from a vertical boiler. The point this museum emphasises is the site's role in fighting the water-borne enteric diseases, especially cholera, that were as rife in small rural towns as in the the Dickensian, East End of London.
SE Dorset has its famous Corfe Castle ruins overlooking the restored Swanage Railway with its new, SR-trim, Norden Station serving a Dorset Council run park-and-ride. Between car-park and station is a small museum devoted to the local ball-clay mining, with a short represantative level. The site itself was not a clay-pit but was instead the transhipment point to the national railways for clay brought there by various narrow-gauge railways from pits in the surrounding countryside, and the museum's short 2ft-g. railway gives a somewhat limited and unfortunately not emphasised flavour of this.
While for the military-minded, Bovington Tank Museum is not ever so far from there.
With Thanks to my appeal on the Wanted Classifieds -
I started sorting out the pre-loved gearbox I bought, err, a while ago, for my Myford ML7. I found the parts I feared lost, and identified the gears therein.
These included the output-side idler with several teeth missing (appropriate for me... ask my dentist!); and a brand-new stock gear I assumed the seller had intended modifying as its replacement.
So last thing this evening I made a split-collet from an oddment of aluminium scaffold-tube, for holding that wheel in the 4-jaw independent chuck.
Prior to closing up for the night and ensuring the cask ale in my local is up the scratch. It was.
Setting the wheel central and boring through for a bronze or 'Oilite' bush is the next task.
551 forum posts
Yesterday I turned off everything in the workshop, shut down my computers and went with my son and my granddaughter, aged 6, to Chessington World of Adventures where I spent lots of money. Best day ever
|Nicholas Farr||13/09/2021 22:24:45|
3360 forum posts
Hi, welded and cleaned up my step-up frame ready for painting.
|Nigel Graham 2||13/09/2021 23:40:53|
|2132 forum posts|
Thanked the two Forum users who had responded to my appeal for help with a Myford screw-cutting gearbox.
It didn't seem to match the details they sent, but a bit more research via lathes.co revealed the unit is an early version - though in very good condition! Still, the lathe itself is of 1947 vintage, so that's appropriate I suppose.
I was intending to machine the replacement idler-gear for the output side, but instead made and used the drilling & tapping template for the two screw-holes needed in the lathe's bed for fitting the gear-box; and spent a bit of time becoming further acquainted with the thing.
6324 forum posts
Well I'm puzzled why Nigel has thanked me for Dr_G's photos of Wortley Top Forge. Though I have mentioned the model engineers there after I visited years ago it was just after they had been flooded right up to the level of the signal box. it is so long ago I can't find the postings or photos. Might be before I had a digital camera.
|Michael Gilligan||13/09/2021 23:50:48|
20182 forum posts
A simple error of punctuation, methinks
|Paul Lousick||14/09/2021 00:30:22|
|2043 forum posts|
The first thing which intrigued me in Dr_G's post was the first photo of what appears to be a variable speed drive. The same principle was used (and still is) for speed control of mechanical equipment.
I remember using "Reeves" Vari-speed drives in the early 1970's. Some of the latest small cars use a CVT gearbox (constantly variable transmission).
The speed of the output shaf depends on the diameters of the pulleys. The flanges of the pulleys are tapered and the belt does not run on the bottom of the pulley but on the sides of the taper. The distance between the flanges is variable and because of the taper, the diameter of the pully where the belt is driven changes in diameter, altering the ratio between the 2 pulleys. I presume the red lever alters the width of the controlling pulley. The flanges of the second pulley are spring loaded and automatically compensates. Speed adjustments are only done when the drive is running.
Edited By Paul Lousick on 14/09/2021 00:56:22
|Nicholas Farr||14/09/2021 07:18:19|
3360 forum posts
Hi Paul, that's what I presumed it is, there was one that drove a 6M filter table where I used to work years ago, but it wasn't as heavy as the one shown, it had a 50 x 16mm belt, which looked a bit like a very wide flat "V" belt. I can't remember exactly how the belt was changed, but I think it had to have the driving pulley partly dismantled and I only changed it a couple of times in the 36 years I worked there, but it would last quite a few years between changes. It was quite a tough belt but it would lose its shape, which meant it was hard to keep a constant speed on the table.
|Paul Lousick||14/09/2021 08:45:51|
|2043 forum posts|
The modern industrial vari-speed belts are like you have said, a wide vee belt, made from a similar, reinforced rubber material. A bit different to the one in the photo with wooden links attached to a flat belt. And different to the belts in the new car CVT drives which are made of thousands of metal parts.
A friend wanted to buy a new car with one of the new transmissions and I did a bit of research and discovered that the belts push to transmit power and not pull like traditional belts. They are very compact compared to a tradition gearbox and although the makers claimed that they were reliable and good for 100,000 plus kms, found that they had a few problems, especially if driven hard and rccommended not to buy one.
|john fletcher 1||14/09/2021 09:05:52|
|792 forum posts|
Nigel regarding early Myford gear box, I had one and fitted it to a lathe about 20 years ago. I think I had to shim the G/box mounting away from the bed to get correct alignment of the lead screw. Also I found much to my dismay several gears with teeth missing, I bough gears from HPC at Chesterfield which I had to sleeve. Took some time, but work out OK in the end. John
1300 forum posts
That was one of the first things I saw. I was intrigued as well, and asked if it was some kind of CVT. To my amazement I was told it was - I though they were a mid-20th century invention (DAF Variomatic was one I think?). Perhaps they’ll have it running at the next open day.
|Mike Hurley||14/09/2021 11:30:47|
|311 forum posts|
DAF Variomatic - correct (unkindley often referred to as ' the one with the rubber-band drive' ) I also used a Raglan lathe for many years having a similar system - was very good to use.
What constantly surprises me with this sort of thing is that there always seems to be someone who's thought of it before! .
|Terry B||14/09/2021 15:07:16|
|15 forum posts|
Robert Boby Seed Cleaning Machines made in Bury St Edmunds until the 1960s had a variable speed on the drive for the winnowing fan that looked identical to the one shown . When you turned the adjusting wheel the bar shown connecting the two pulleys pivoted and moved one pulley disc out simultaneously moving the other in thereby varying the speed.
This thread is closed.
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