Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 7, 2022 0:32:48 GMT
Using drills that size can be eye-watering too, they are horrible brutes (reamers not so much). I can’t remember any occasion to use big drills, and that is in 7.25” gauge! Arm yourself with a boring tool, it is slower but much safer. And some step drills for drilling plate. Slot drills and end mills can be used to drill holes too, though in a limited range of sizes and you need to drill a pilot hole first. (But that is usual, even with twist drills). HTH Gary
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Post by davewoo on Feb 7, 2022 8:18:49 GMT
Hi William I used oilite bushes in steel axleboxes with mild steel axles on my Simplex which has done a lot of running, it was done for cost reasons but not one of my best decisions. The oilite has picked up ash and particularly on the trailing wheels this has acted like grinding paste and has worn the axle to a horrendous extent. I was looking to start steaming it again, but it's so bad I really must sort it out before use, could do with a repaint anyway, looks like something from Barry Island at present. Oilite is probably fine if you can keep the grit out of the bearing,not easy on an inside cylinder loco with a crankshaft. I've now gone over to using cast iron for axleboxes, but neither C.I or gunmetal seem to give problems on friends loco's that have done a considerable mileage. Good luck with the loco, keep us updated on your progress, we all seem to like a build log! Dave
PS Agree with Gary re step drills, only recently realised how useful they are, had them for years but must be slow on the uptake!
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stevep
Elder Statesman
Posts: 1,070
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Post by stevep on Feb 7, 2022 10:19:04 GMT
I have used oilite bushes in mild steel axleboxes on my Rob Roy, with silver steel axles. After 30+ years, it's still going fine.
I used ground mild steel axles in cast iron axleboxes on the Stanier, and that seemed fine.
Cast iron cylinders are fine - but remember to squirt lots of oil/WD40 into them after steaming, or you will find they rust and jam. They are also perfect for use with conventional rings. (I use Honda 50 rings in my Stanier).
I would be a bit uncomfortable with gunmetal covers in CI cylinders. You would normally have a close fitting register on the covers to fit the bore of the cylinder. Gunmetal would expand more than CI and I could see that as a potential problem.
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Post by William A on Feb 7, 2022 13:39:07 GMT
OK, thank you for the advice!
Cutting them off (or removing the wheels) sounds pretty intense, so I think I wll go for split CI axleboxes - that way if it really does all go pete tong I can replace them with bronze equivalents in future. Any thoughts on loctite vs press-on wheels - I won't need to do it now but I can keep an eye out for an arbor press in the meantime if it'll be neccesary...
With regard to the cylinder covers my thoughts were the same as yours stevep, i.e. the inequal expension. I have noticed that the valve gather a similar but less pronounced concern with the valve chest?
Now I'm just sitting on my hands waiting for parts!
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Post by William A on Feb 9, 2022 15:45:19 GMT
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 9, 2022 23:39:04 GMT
Hi Wiliam
There’s no possible harm from posting links like that one. Nobody is forced to read it or follow it! It is a novel approach, so why not?
Gary
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Post by William A on Feb 14, 2022 10:13:03 GMT
Thanks Gary, I'll keep doing it incase it's of any value (most likely entertainment than educational, Ha!) www.youtube.com/watch?v=y1gpovinN48This was my first attempt at machining parts with any kind of accuracy beyond calibrated eye - I think it went quite well, personally. I unfortunately pulled my back (again) putting up some lights yesterday so the next parts (hornstay screws and spring pins) are going to have to wait a little while I'm afraid...
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Post by William A on Feb 16, 2022 13:26:02 GMT
A really rather pedestrian video on machining up the hornstay screws (that's what Curly calls them!):
I have noticed a few nubs on the bolt ends in this video, so will need to tidy those up - and depending on how much this kind of repetitive work turns up in the build, it may well be sensible to sort myself an indexable carriage/apron stop.
Axleboxes and Spring Pins
JCSteam has kindly pointed out that in this build Curly does not indicate relieving the axlebox slots to account for track irregularities, or opening out the spring pin holes to allow the axleboxes to roll slightly.
My Centec only has a 28" x 5" table so fitting a rotary table large enough to comfortably machine this might be an issue. I was thinking of using the horizontal miller to cut the slots parallel, and then using a swivel vice to relieve and then blend with a file.
I've done various calculations for the 'perfect' radius and various multi-faceted straight cuts, but is this overthinking things? The linked thread suggests relieving the top and bottom of each flange by a few degrees (i.e. way wider than the perfect radius) and blending the three or five face with a file should be sufficient.
Hornstay Spring-Pin Holes
The maximum left-right deflection of the spring pins as tangent to 4-3/8" radius circle and offset by 15/16" (the midpoint to bottom of the axlebox) is about 1/8" - so opening the hornstays out to a pill shape by 1/16" in either direction should be sufficient, eh?
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Post by William A on Feb 17, 2022 16:15:35 GMT
I have received a box of raw castings, and a few machined parts - two of which are the main frames which have been drilled for fixing and have the horns mounted. One is slightly bowed but other than that they look good - and there’s a completed bogie!
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Post by ettingtonliam on Feb 17, 2022 19:37:56 GMT
A really rather pedestrian video on machining up the hornstay screws (that's what Curly calls them!):
I have noticed a few nubs on the bolt ends in this video, so will need to tidy those up - and depending on how much this kind of repetitive work turns up in the build, it may well be sensible to sort myself an indexable carriage/apron stop. Axleboxes and Spring Pins
JCSteam has kindly pointed out that in this build Curly does not indicate relieving the axlebox slots to account for track irregularities, or opening out the spring pin holes to allow the axleboxes to roll slightly.
My Centec only has a 28" x 5" table so fitting a rotary table large enough to comfortably machine this might be an issue. I was thinking of using the horizontal miller to cut the slots parallel, and then using a swivel vice to relieve and then blend with a file.
I've done various calculations for the 'perfect' radius and various multi-faceted straight cuts, but is this overthinking things? The linked thread suggests relieving the top and bottom of each flange by a few degrees (i.e. way wider than the perfect radius) and blending the three or five face with a file should be sufficient. Hornstay Spring-Pin Holes
The maximum left-right deflection of the spring pins as tangent to 4-3/8" radius circle and offset by 15/16" (the midpoint to bottom of the axlebox) is about 1/8" - so opening the hornstays out to a pill shape by 1/16" in either direction should be sufficient, eh?
I must confess to easing the axleboxes with a few strokes of a fine file. It seems to work. No machining, no calculations. Just as an aside, should the heads of ypur bolts be quite that thick? Doesn't look right somehow.
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Post by steamer5 on Feb 18, 2022 8:52:19 GMT
Hi Willam, Just had a look on the fullsize drawing for K1. The axlebox is 1' 1 1/8" tall, the axel box slide gap at the top & bottom is 5", at the middle 4 7/8". these are 3/4" deep but dont show any relief on depth. Like Richard said out with the file to allow some rock to allow the axel box to ride up & twist a bit to accommodate uneven rail, but only enough to get smooth operation fore & aft.
Cheers Kerrin
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Post by William A on Feb 20, 2022 22:47:24 GMT
The bolt heads look over thick but are specifically specced out by Curly Lawrence as 3/16". I think I may re-make these as square headed bolts and if I do, I'll make them with thinner heads:
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Post by William A on Feb 21, 2022 7:42:35 GMT
Two small videos on the L-class this weekend - nothing dramatic in these ones, just a bit of housekeeping on the series so far:
And two...
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Post by William A on Feb 21, 2022 14:32:15 GMT
I need to think about boilers, given the wait times if I go commercial. From the get-go I wanted to build my own boiler, and to hand I already have the flues, steel formers for the firebox and firebox-wrapper, and a pre-flanged smokebox tube-plate. While I already have a Sievert propane torch and an embryonic hearth, I also have basically no experience with any meaningful silver brazing at all at this stage. I make the rough cost to be about £400 for the balance of materials plus consumables. Now, it would appear that in the time Curly was writing the M.E. series there was an expectation this work would be undertaken as part of the locomotive build, but it seems that most people these days outsource this to dedicated boilersmiths either by association or commercially. Why is this? Clearly, I'm starting at the bottom of the skill tree and I have all the enthusiasm but none of the required experience. So, despite a desire to do it all myself - I wonder that it may be a better bet to pay for a commercial one and focus my efforts where my meagre experience is starting to pay off. To that end I have enquired from Western Steam and Southern Boiler Works. I would love to hear any advice on the pros/cons/etc. that the more experienced may have to offer on this as it's a decision I'll have to make soon(ish)
EDIT: Just got quoted the thick end of £4k inc. vat for a boiler so let's just say I'm hoping that 'it'll be fine just take your time and do it yourself' is a reasonable option...
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mbrown
Elder Statesman
Posts: 1,719
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Post by mbrown on Feb 21, 2022 15:19:33 GMT
I had my first boiler (for a 2.5"g Southern Maid) built by Fred Stone in 1970 for £26 !
Since then I have always built my own boilers although none of them are as big as MoK. I use one Bullfinch torch with the largest burner, backed up for the biggest heats with a smaller torch - but the big one could probably have done it on its own. For a MoK boiler you are almost certain to need two torches and that really means co-opting a second pair of hands.
If you look a few pages back in my build thread on 99 3462 you can see the stage by stage description of building my 4" dia boiler (including resolving a nasty leak which appeared on test). It may help you see what is involved.
I would say the key thing is to have a good pickle tank, which helps ensure cleanliness, and more silver solder than you thought you'd need. And then take it gently step by step.
Good luck!
Malcolm
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uuu
Elder Statesman
your message here...
Posts: 2,808
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Post by uuu on Feb 21, 2022 15:46:46 GMT
Have a look at Steve's (springcrocus) Britannia thread - about here is the start: Steve's Brit thread page 36. Steve had not built a boiler before and this was a quite a complicated one. But the materials were so much cheaper than a commercial boiler, the decision was an easy one. It's better with two people, two torches are better than one, so find yourself a buddy - I was Steve's buddy. And you can share the blame for the inevitable disasters. Steve seemed to get the knack of copper bashing - I suspect the good formers he made were part of it. So there were no big gaps in joints. Laying solder strips/rings in a bed of flux and heating until it flashed through worked well. We found that cleaning, refluxing and re-heating, to remedy lack of penetration, was easy, provided it was done at the time - not three stages later. Good luck! Wilf
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Post by andrewtoplis on Feb 22, 2022 16:11:35 GMT
I have received a box of raw castings, and a few machined parts - two of which are the main frames which have been drilled for fixing and have the horns mounted. One is slightly bowed but other than that they look good - and there’s a completed bogie! Did you buy that from ebay a few days ago, with the painted wheels and completed bogie?
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Post by William A on Feb 23, 2022 10:28:40 GMT
Wilf; Malcolm - thank you for the advice and links. Andrew Brock of Beech Hurst has also encouraged me to give it a shot, but I think I would need to iterate a little before attempting a silver brazed assembly of this size and I'm not sure (with forthcoming arrival of firstborn child!) that I can afford the various dry runs. Speaking to Western Steam, they are happy to offer a refund on the deposit (20%) if I cancal my order before materials are ordered and work undertaken - so really though they'll be holding on to my £568 for the meantime, but it feels like a win-win situation - either I take to boilersmithing like a duck to water and I can then cancel my order, or I run out of time/it doesn't work out and I'm X months closer to an item landing in my lap. Andrew, I didn't buy it on eBay, I bought it from Facebook for approx £500+pp comprising: Two subassemblies: - Completed, but rusty bogie - Main frames with horns mounted, beams and stretchers machined but loose - Running boards (L1-style, won't be using)
Some machined parts: - Coupled axle - Driving and coupled wheels - One bronze axlebox - Cab sides (L1-style, won't be using)
And some blanks or unmachined castings: - Inside cylinder casting set (with C.I. block, Gunmetal elsewhere) - Components for a Stephensons Link (which I will be putting aside in favour of a Joy motion) - Internal and external crossheads - Smokebox, smokebox door, chimney - Inner & Outer steam dome
- Boiler flues, formers and one flanged plate - Tender wheels The previous owner had collected these various parts together in order to build the locomotive but put it aside when a completed item became available. It all seems to be machined to a fair standard - certainly no worse than I could achieve! I also purchased some laser cut parts from MEL for £176: - Coupling rods - Connecting rods - main, tender and bogie frames This order was placed before I found the 'box of bits' !
I still will need to buy all the hundreds of bolts, nuts, studding and maybe aLastly, I purchased sundry materials from M-Machine metals to the tune of roughly £100 so far. replacement cylinder block (i.e. Gunmetal rather than CI), as well as all the brass and fittings - it looks like a project of around £4k total? I'm sure I'll look back at this and laugh.
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Post by andrewtoplis on Feb 23, 2022 14:39:36 GMT
Ok, there was a bits box up the other day.
There is a completed one for £4.5k too if it all feels too much 🤣
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kipford
Statesman
Building a Don Young 5" Gauge Aspinall Class 27
Posts: 566
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Post by kipford on Feb 23, 2022 17:16:39 GMT
William I am making my own boiler at the moment and finding it an enjoyable experience. IMO go for it, I considered it well worth the risk of scrapping the boiler against needlessly spending many £k's of money to have one built.
Dave
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