Here is a list of all the postings John Baguley has made in our forums. Click on a thread name to jump to the thread.
|Thread: Hallite washers|
There really is no need for the washers but I presume that you have made the parts to the drawings so the gap for the O ring will be too big for the O ring alone. Your PTFE should be fine to make the washers or you could just make a spacer washer out of brass (put on the boiler side of the O ring) to make the gap the right width for the O ring on it's own.
I've used the O ring seal on several locos and it works very well. Much better than the threaded joints beloved by LBSC which are an absolute pain!
It's a bit confusing as the rods of both types become open or crossed at some point in their motion!
The way to tell if the valve gear has 'open' or 'crossed' rods is how the rods look when the crankpin is on the opposite side of the axle to the eccentric.
The majority, if not all, of loco valve gears use open rods. I don't think it makes any make any difference if the gear uses a rocker or not.
With open rods the amount of lead increases as the cut off approaches mid gear. It is often necessary to set the gear to give zero or even negative lead in full gear to avoid the lead becoming excessive as the gear is notched up.
With crossed rods the amount of lead decreases as the gear is notched up. I believe crossed rods are normally used on traction engines rather than locomotives.
Hope that helps.
|Thread: Pesky Government Announcement!|
I haven't had a TV for about 25 years now and used to get a constant stream of letters from the TV Licensing 'thugs'. I did get a note shoved through the letterbox one night saying that the TV detector vans had been in my area and if I had been caught using a TV then I would have been prosecuted. Good luck to them as they wouldn't have caught me using one anyway! They would have a job spotting the TV aerial as it fell off the chimney about 10 years ago!
I think they have finally given up harassing me and now I just have to 'sign' an online declaration every two years to say that I still do not need a licence.
I did use to watch BBC Iplayer occasionally on the computer until they decided a few years ago that you need a license to watch that so I don't even bother with that now. I don't think that I am missing anything. There's plenty of far more interesting stuff to watch on YouTube if I get bored.
|Thread: 3D or 2D Drawings for SAR 25C|
The drawings that SAR Steam sell are very good quality copies of the works drawings in Tiff and pdf format. There are also some CAD drawings included, at least in the 25NC set. I've got the set of three CDs containing the drawings for every SAR loco that they sold some years ago when the owner was thinking of shutting shop.
I have been slowly drawing up a 2½" gauge version of Red Devil over the last few years but whether it will ever get built is another matter!
Be aware that following works drawings is a mammoth task and will take a long time!
Jim Nolan is building a 7¼" 25NC and shows progress on his website:
Worth a look if you want to see what is involved in building a loco of this size. It's huge!
Edited By John Baguley on 12/06/2020 01:48:17
|Thread: LBSC 3.5" "Maisie" - steam regulator valve assembly|
Here's the drawing of the regulator arrangement:
To remove it you will have to first unscrew the fitting on the front tubeplate. It threads into the tubeplate and onto the end of the steampipe at the same time so will not be easy. You will either have to try and grip the outside with something or maybe put a couple of screws into the threaded holes that hold the superheater on and try unscewing it with a bar.
The steampipe may come out with the fitting. If not, you will have to remove it by unscrewing it from the regulator block. One way is to tap the square end of a file shank into the end of the pipe or a square file and use that to unscrew it. You will probably damage the pipe trying to get it out!
Once the steampipe is removed you should be able to remove the regulator block through the dome bush after removing the screw on the top of the boiler that holds it.
Hope that helps,
|Thread: DRO error|
Don't worry about it Kevin. I did something similar the other night. I also wanted four holes, put the start angle as 90° but put the end angle as 270°. Took me a while to realise what I was doing wrong.
Only just learnt the difference between Absolute and Incremental measuring after watching a YouTube video by Joe Pie!
I think it's because you have put the end angle in as 0°. It should be 360°
The DRO is thinking that you want the four holes to cover an angle of 90° instead of the full 360°.
Edited By John Baguley on 23/05/2020 01:01:26
|Thread: It would happen now!|
Another disadvantage of a combi is that you can waste a lot of water waiting for the hot water to come through, unless you have the type with a built in storage tank. In the kitchen I run the water into a 2 litre milk bottle until it gets hot and use that to fill the kettle.
|Thread: 5" gauge terrier build|
For removable plugs so you can see the valves and ports for setting the timing. The drawing in ME shows them as 3/8" x 40
|Thread: Cost of Stamps to Increase|
I send everything first class. The difference in cost is negligible. It's still cheap at the price.
|Thread: Did i make the right choice buying an old banger Myford lathe.|
When I started model engineering back in the early 70's there wasn't much choice if you wanted a decent small lathe. You were pretty much limited to a Myford. My 'workshop' was the small box room of my parents house so a s/h ex-industrial lathe was out of the question plus it would probably be completely clapped out.
There just wasn't the vast choice that people have nowadays so that's probably why there are so many Myfords around. At the time they were 'the' model engineers lathe.
The small spindle bore is a pain but I've now got a restored Denham Junior for anything that the Myford won't handle.
Would I buy a Myford now if I were just starting out? Probably not unless one came up in very good condition at a reasonable price. I would go for something bigger and it probably would be a larger new asian machine.
I still like the Myford though and wouldn't part with it
|Thread: Linked belt for Myford 7|
Last year I replaced the plain Vee belts on my ML7 with cogged Vee belts. These are more flexible than the plain type and made a big difference to the smoothness of the lathe. It's only a 10 minute job to take the spindle out to change the belt.
I discovered the cogged belts after having vibration problems with my mill after getting rid of the standard twin belt stepped pulley drive and fitting a single belt 3 phase inverter drive. With a conventional Vee belt I got horrendous vibration due to the long belt flapping about. I looked at linked belts and promptly decided against them due to the price! As a last resort I tried a cogged belt and that transformed things immediately. There is still a slight vibration at higher speeds but nothing like it was with the conventional belt.
|Thread: Rob Roy lubricator to valve chest connections|
Yes, it's a pretty naff design really. A better way would be to have the steam enter the steamchest on the front edge via a couple of flanged elbows. I might alter the chassis that I've got to do that when I get around to completing the loco.
Here you go - a couple of photos of a chassis that I picked up last year:
The oil pipe from the lubricator feeds into a clack screwed into the front of the block in the middle of the steam manifold.
Hope that helps
|Thread: Screw Regulator dimensions|
The PEEK that I used (because I had some!) was a bearing grade PEEK that contains carbon fibre, graphite and PTFE (Ketron PEEK-HPV). I originally got a 300mm length from RS but they don't seem to have that grade anymore. They do have black PEEK that contains carbon but it's not cheap!
I then got a 1 metre length of similar bearing grade PEEK from Davis Industrial Plastics (Bunaday on Ebay). They do list the ordinary plain PEEK on Ebay. That may be suitable but I've never tried it.
The bearing grade PEEK takes threads very well which was necessary in my design as the block screws into the end of the regulator body and the steam pipe screws into the block. It also makes a perfect seal which is useful when you are doing a hydraulic test.
If you struggle to find anything suitable, I've still got some 12mm diameter left and could send you a couple of inches.
You could possibly use PTFE or maybe the carbon filled PTFE which is a bit harder?
My Helen Longish has a screw down regulator. The thread is 3/8" BSW, the hole in the port face is 3/16" and the angle on the end of the valve spindle is 120°. The loco has 3 off 7/8" bore cylinders and for normal running I never have to open the regulator more than 1/8 of a turn. Use a quarter turn and she takes off like a scalded cat!
The end fitting that has the port face is made from bearing grade PEEK which avoids the problem of the regulator seizing up if fitted with a metal port face and you forget to open the regulator when the boiler cools down.
|Thread: Digital readout|
I ordered one direct from China a couple of years ago. I had to pay about £20 VAT and duty but it was still half the price of one bought from the UK. It took about two weeks to arrive.
|Thread: Can we have a really clear distinction between Silver Soldering and Brazing|
Silver soldering as we think of it should really be called silver brazing as mentioned by Mike. Any joining process involving temperatures over 450°C(?) is classed as brazing, below that is classed as soldering.
A friend of mine in our club has had it for a few years but he keeps fighting it by, as mentioned, keeping his brain active. He's designed and built two superb 2½" gauge locos and is now working on a third. He's also building a Vee twin petrol engine and a hit and miss engine. He's determined to carry on model engineering as long as he possibly can. He puts a lot of us too shame!
To make matters worse, he's also got Parkinson's which is slowly getting worse, but he takes it all in good heart and doesn't let it get him down. I think that is what helps to keep him going.
|Thread: Chinese DRO opinions|
I bought a very similar set from China a couple of years ago for the mill and I've been very happy with it. I didn't go for the cheapest though. I got a Sinpo brand which seems to have a pretty good reputation which was around £200. It took two weeks to arrive which was no problem and I had to pay £21 VAT etc. I would certainly purchase direct from China again when I want another one.
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