Here is a list of all the postings Bob Wild has made in our forums. Click on a thread name to jump to the thread.
Thread: Merryweather Steam Fire King self propelled |
02/06/2021 20:19:43 |
Good fun to watch too 👍 |
Thread: Merryweather Fire King |
26/05/2021 20:23:41 |
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23/05/2021 23:06:02 |
Hi Werner. Thanks for your reply - it’s always interesting to hear of other people’s experiences. As I mentioned it took me ages to get everything lined up. I did make all the clearance holes wherever I could to be much larger than they should have been and I tightened them up progressively to get the smoothest fit. So, I am going to have another go at prefabricating the crankshaft and will hope for the best. Anyway, I will have a little time to ponder as my dear wife wants me to take her in our caravan for a few weeks on one of our rare visits to the south of England!!!! Bob Edited By Bob Wild on 23/05/2021 23:07:19 |
22/05/2021 00:05:21 |
Still struggling on. Finally got the engine assembled and after ages finding the tight spots (I now have a new meaning to the term “Quantitative Easing) it now turned over relatively smoothly. First run on air would not rotate, but there was a significant downward thrust at times. I had followed the dimensions in the book for the valve mechanism, which occurred to me was a metric conversion from the original imperial drawings. Upon reflection it occurred to me that there may be minor differences. So I reduced the width of the slide valve by ten thou each side. After a lot of fiddling with the timing - bingo, it run. It needed twenty psi to get it started, but it ran like the clappers and nearly shook itself off the bench! And then disaster. The crankshaft had come loose. I had prefabricated it, cross pinned it and loctited it, but two of the joints had come loose. So off to make another. I don’t think I can retrieve it so it’s a matter of staring from scratch. I’m wondering whether to persevere with loctite or to try and silver solder it or even soft solder it. I’m a bit concerned that if I use solder that it will distort. Help please, this is driving me mad!!!!!
Bob |
Thread: Recommended suppliers and services |
11/05/2021 17:12:24 |
Can thoroughly recommend Derek Harper Foundries in Bradford (UK). They cast non-ferrous metals. I gave them a couple of patterns for my Fire King, and they were ready in three days. Quality looks fine; no apparent blowholes or inclusions. Reasonable price (to me) and a most helpful guy, who even replied to my email on a Sunday afternoon. Very impressed.! Bob |
Thread: How on earth do I build this boiler for my Fire King ? |
02/05/2021 22:45:54 |
Thanks chaps for all your useful comments, and sorry about the delay in replying. SWMBO insisted on using the relaxing of lockdown to use the opportunity to go off in our caravan for a much needed break. Anyway, I have made a strategic decision which may not meet with the approval of some. This model will only run on air. Firstly, it makes the construction simpler and secondly, it means that I can show it in my display cabinet along with my other models. As I said earlier, if it was good enough for Cherry Hill then it’s good enough for me. |
08/04/2021 17:09:56 |
Here's a drawing of the modified boiler, taking account the various suggestions I've received. The changes are :
Any thoughts about these changes? One immediate benefit that I can see is that I only need one casting. Although the foundry I found quoted quite a reasonable price and fairly quick delivery. Apparently he gets quite a few similar requests from model locomotive builders. I am thinking that I may need to use different melting point solders and build it in stages. Any advice would be most appreciated. By the way the boiler is 4in dia and overall height is 10 in. Bob Edited By Bob Wild on 08/04/2021 17:10:37 |
Thread: Java 0-4-2 O+K De Maas Sugar Mill Locomotive |
06/04/2021 15:48:33 |
Brilliant, I'll be watching your progress avidly. Bob |
Thread: How on earth do I build this boiler for my Fire King ? |
01/04/2021 19:44:50 |
Thanks Nigel. More good ideas. |
31/03/2021 23:03:59 |
Thanks Jason, this is all getting very interesting. I like the idea of a separate ring to take the rivets. In fact I have some round headed ba screws with no slot. I could use these and they would look just like rivets. I can certainly increase the height of the shell to increase the separation of the top dome and smokebox ring. I am considering doing away with the cone shape on the outer lower ring which would mean I could just extend the whole outer shell down to the bottom of the boiler. And as you suggest I could use an L shaped ring to hold some dummy rivets. If I increase the angle of the inner cone I can make it butt join directly with the outer shell. I don't mind not having any rivets at the base since this is right at the bottom of the boiler and right out of sight. I can get rid of the 12 bent fire tubes and replace them with a couple of pairs horizontally across the top of the fire box. Not sure if Cherry Hill would approve of all these changes, but what the heck. I am starting to draw this out (slowly). Incidentally I have spoken with Gégé and he tells me he did use a gas burner in the end. I presume this also will give a higher heat output than the spirit version. He also said he made the conical parts by wrapping a sheet round a former and the soldering the seam. I would have preferred to use a tube the same diameter as the small end, and then try and swage it up a former. Any thoughts? Bob |
30/03/2021 16:50:51 |
Chaps, thanks for so many constructive and detailed points. I think the general consensus is that it could be simplified' I have had a few thoughts about this and will post a sketch shortly. I do have a few specific queries: Nigel - what is a fire hole tube? The design shows a spirit burner mounted directly below the boiler. A bit more iinfo on the spear point would help. Jason - How do you fasten dummy rivets to the copper tube. I like this idea. Keith - I looked up "Keith Hale" on Amazon books, I have been in touch with Gege in France who has bee most helpful, and also Werner in Germany. Having read up about the Fire King it seems that the boiler was not lagged. Another interesting fact is that the total time for working pressure to get underway was about 6 minutes! Bob Edited By JasonB on 31/03/2021 07:08:35 |
Thread: Merryweather Fire King |
28/03/2021 23:12:42 |
Nearly finished the engine, and started to think about the boiler. So I posted this thread to aim at a wider audience, asking for advice on what, to me, looks like a daunting part of the build: https://www.model-engineer.co.uk/forums/postings.asp?th=172017 Looking for any helpful advice. Bob
Edited By Bob Wild on 28/03/2021 23:14:22 |
Thread: How on earth do I build this boiler for my Fire King ? |
28/03/2021 23:08:41 |
Here is an assembly drawing for my boiler: There are many features which frighten me:
Any advice from those more experienced than me would be most appreciated. Bob
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Thread: Merryweather Fire King |
19/03/2021 22:56:30 |
Finally got all the parts for the engine finished. First the crossheads: and with the pistons and crankshaft: and to show my new and finally the valve chest and other bits: Spent ages lining everything up and getting things to move almost freely. I've got a way of mounting the assembly on the lathe so I can then try and run it in and get it rotating smoothly.
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Thread: What is running-in oil? |
10/03/2021 22:44:22 |
Thanks chaps for all your helpful and interesting comments. They certainly have given me something to think about. Bob |
09/03/2021 12:20:04 |
Slowly getting to the point of finishing the engine for my Merryweather Fire King. I have read that it needs running in with a special running-in oil. I cursory search reveals that such products do exist, but they seam to be aimed at cars, and come in 5 litre containers. So, what is this oil, and can I get just a cupful ? Bob |
Thread: What nut and bolt material? |
15/01/2021 22:31:38 |
Never dreamt that my simple question would provoke such a heated discussion. But apart from Hopper’s suggestion about a bit of brass bling not many other posts address my initial issue 🙁 |
14/01/2021 11:48:05 |
Thanks Hopper. Paul - that’s a good idea. I like a bit of bling. And I have some brass nuts left over from an earlier job, so I can try those. |
Thread: Merryweather Fire King |
14/01/2021 00:03:43 |
Oh this is so hard (for me). Not much progress in the last two months, but a lot of effort. Got the leak test going on the water pump and it failed miserably. The culprit being the soldering of the cylinders to their backplates. I figured out that I was paying too much attention to appearance by putting a neat bead of solder between the mating faces. So, two attempts later I finally smothered the joints with solder and ‘Bingo’. It finally was sealed OK. |
Thread: What nut and bolt material? |
13/01/2021 23:12:14 |
I’ve been building my Fire King for a year now. I notice that many of the nuts and bolts that have been in for a while are starting to look a bit tarnished as if starting to go rusty. That’s not pretty to me. So, I hit upon the idea of replacing them with stainless steel ones. Is this a silly idea or are there any alternative solutions? Bob |
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