Gary L
Elder Statesman
Posts: 1,208
|
Post by Gary L on Jun 20, 2019 20:17:33 GMT
Interesting discussion on dampers etc, I'm sure there's a good reason that they weren't used in full size but if really wanting some form of suspension within a set of locomotive frames I think that I would be looking at a 'torsion bar' setup. It works for main battle tanks at high speed and some of those are just as heavy as a tank loco, work very well on my car too... Pete Hi Pete, I suspect dampers weren't used simply because they could get away without fitting them, even if the ride was scary at high speed. I guess most locomotives never went that fast, so it would only be express locomotives that might run into trouble if they happened upon a piece of track that reinforced the oscillation. I'm sure you won't find a diesel or electric locomotive without dampers, and presumably those aren't as top heavy as Steam Locomotives. Maybe the leaf springs add just enough damping to be able to cope with the worst of the conditions Steam Locomotives encounter... That is more or less the case. Leaf springs have a certain amount of inherent friction damping.I believe it was only the advent of coil springing that made improved dampers essential on road vehicles, prior to that, with ‘cart springs,’ dampers were pretty crude if they existed at all. So the purists cannot criticise Roger for experimenting with dampers; you could argue that they are made necessary by using non-prototypical coil springs, as most of us do. Don’t modern electrics also have coil-sprung bogies too, hence the dampers? -Gary
|
|
dscott
Elder Statesman
Posts: 2,438
|
Post by dscott on Jun 21, 2019 2:11:28 GMT
The only way not to have BOUNCE is 3 point Suspension as fitted to my Battery Drill driver loco. Grips the track but even sitting on it you get wheelspin. But you do not need to adjust.
So solid axle in the middle which helps the valve gear. Pivot the front pair where all the weight is. Pivot the rear from a sprung point from under the ash pan. I now have the horns as a complete box of 10mm plates with 3mm plates top and bottom in the Ash Pan area of the Simplex Fowler Complex. She is coming over all experimental!
David.
|
|
|
Post by 92220 on Jun 21, 2019 8:28:59 GMT
The fillers have a tiny split pin that goes through the 0.6mm hole in the pivot pin. I've made some using Florist's wire, but those will go rusty if I use them where there's going to be water. I found this wire on eBay which was actually described as being Silver plated Brass wire. As it happens it's Copper, but it's good enough. 20190618_172328 by Anne Froud, on Flickr 20190618_173107 by Anne Froud, on Flickr The same 'mangle' works just as well with this wire to form the required 'D' shape from the initial round section. The flat side is wrapped around the former and cut to length. 20190619_213728 by Anne Froud, on Flickr It's pretty small. The idea of using Silver plated wire is so that they look like they're Steel but they won't rust. 20190619_213909 by Anne Froud, on Flickr Hi Roger. Thanks for showing how you make your miniature split pins. I have often wondered. That is VERY useful info!! Bob Edit: Like a twit I marked my own post with a 'Like', when I meant to mark Roger's post!!
|
|
|
Post by Roger on Jun 21, 2019 9:28:19 GMT
The fillers have a tiny split pin that goes through the 0.6mm hole in the pivot pin. I've made some using Florist's wire, but those will go rusty if I use them where there's going to be water. I found this wire on eBay which was actually described as being Silver plated Brass wire. As it happens it's Copper, but it's good enough. Hi Roger. Thanks for showing how you make your miniature split pins. I have often wondered. That is VERY useful info!! Bob Hi Bob, I worked out the cross sectional area of the required 'D' shape for half of the split pin, then bought wire with the closest cross section when round. Florist's Iron Wire is what I normally use, it's very cheap but you need to make sure they deliver what they say it is, and not substitute a different diameter which is what happened to me on one occasion. I use dry Graphite lubricant to get it to release from the forming wheel because it can get properly stuck in there. The work hardening makes them plenty strong enough. Just let me know if you need any and I'll make you a few lengths. I have enough wire to last me a lifetime.
|
|
|
Post by 92220 on Jun 21, 2019 16:13:37 GMT
Hi Roger.
Thanks for that offer. It would save having to make a 'D' roller that I would probably only ever use once. Very much appreciated.
Bob.
|
|
|
Post by ettingtonliam on Jun 21, 2019 16:36:41 GMT
I know they are enormous by Roger's standards, but I've got a box of original Nettlefolds 1/32" dia split pins if anyone needs a few. Had them for years, probably used 6, I know I'll need some for Locomotion, but can spare some.
|
|
|
Post by Roger on Jun 21, 2019 17:02:37 GMT
I know they are enormous by Roger's standards, but I've got a box of original Nettlefolds 1/32" dia split pins if anyone needs a few. Had them for years, probably used 6, I know I'll need some for Locomotion, but can spare some. That's a very generous offer, and it made me think of an idea for future meets at Doncaster/Midlands or whatever shows we attend. As well as bringing along something to show, how about bringing the odd surplus items that would gratefully find a home? I could run off some 'D' section wire for micro split pins and bring along some Titanium Welding rod to hand around. Actually, this is really Jim Scott's idea since he kindly brought something along for me at Doncaster.
|
|
JonL
Elder Statesman
WWSME (Wiltshire)
Posts: 2,907
|
Post by JonL on Jun 21, 2019 17:26:19 GMT
I know they are enormous by Roger's standards, but I've got a box of original Nettlefolds 1/32" dia split pins if anyone needs a few. Had them for years, probably used 6, I know I'll need some for Locomotion, but can spare some. That's a very generous offer, and it made me think of an idea for future meets at Doncaster/Midlands or whatever shows we attend. As well as bringing along something to show, how about bringing the odd surplus items that would gratefully find a home? I could run off some 'D' section wire for micro split pins and bring along some Titanium Welding rod to hand around. That's a great idea. Might suggest it at our next club night.
|
|
|
Post by Roger on Jun 21, 2019 21:27:22 GMT
The Pannier Tanks on 1501 have wooden pads between all of the mounting brackets, I'm not entirely sure why. Anyway, they scale to almost exactly 0.6mm which happens to be an available size in Tufnol. So here I'm machining out a set using PCB cutters, a 1mm 2-flute being used for the profile. The clamp in the foreground is just to hold it down, the back is secured by packing tape. 20190621_205124 by Anne Froud, on Flickr The tanks are very slightly different heights, so I've made a few extras in case I want to pack one side up more than the other. I doubt if it will be necessary, but it's easier to do this now. 20190621_215649 by Anne Froud, on Flickr The material wants to de-laminate, there are a few spots where it isn't perfect, but it's good enough. 20190621_221922 by Anne Froud, on Flickr
|
|
|
Post by delaplume on Jun 21, 2019 23:10:58 GMT
The Pannier Tanks on 1501 have wooden pads between all of the mounting brackets, I'm not entirely sure why. Anyway, they scale to almost exactly 0.6mm which happens to be an available size in Tufnol. So here I'm machining out a set using PCB cutters, a 1mm 2-flute being used for the profile. The clamp in the foreground is just to hold it down, the back is secured by packing tape. 20190621_205124 by Anne Froud, on Flickr The tanks are very slightly different heights, so I've made a few extras in case I want to pack one side up more than the other. I doubt if it will be necessary, but it's easier to do this now. 20190621_215649 by Anne Froud, on Flickr The material wants to de-laminate, there are a few spots where it isn't perfect, but it's good enough. 20190621_221922 by Anne Froud, on Flickr The wooden pads may be as a form of resilient mounting ??...........I wonder what 57xx and 94xx have ??
|
|
|
Post by 92220 on Jun 22, 2019 7:43:00 GMT
Interestingly, all the BR standard design tenders have strips of wood that the tank rests on, on the chassis too.
Bob.
|
|
|
Post by Roger on Jun 22, 2019 7:46:04 GMT
The Pannier Tanks on 1501 have wooden pads between all of the mounting brackets, I'm not entirely sure why. Anyway, they scale to almost exactly 0.6mm which happens to be an available size in Tufnol. So here I'm machining out a set using PCB cutters, a 1mm 2-flute being used for the profile. The clamp in the foreground is just to hold it down, the back is secured by packing tape. The wooden pads may be as a form of resilient mounting ??...........I wonder what 57xx and 94xx have ?? That's possibly the reason, it would make for a softer connection. There's a lot of weight on the mounts, and the tanks are going to be trying to twist and move around. Maybe without them they chafe and squeak around, risking the bolts breaking?
|
|
|
Post by 92220 on Jun 22, 2019 7:56:34 GMT
Hi Roger.
I am looking at the clothing for my boiler and see I have to beat out 3 separate shapes in 2mm brass. Do you think MDF would stand up as the forming shape or is it necessary to use metal? I'm just thinking they will be only used once and to produce them in metal is going to take a lot of time. I see you have used steel, but if I must use metal, would aluminium be OK as it is much easier to cut and file to shape?
Bob.
|
|
|
Post by Roger on Jun 22, 2019 8:55:58 GMT
Hi Roger. I am looking at the clothing for my boiler and see I have to beat out 3 separate shapes in 2mm brass. Do you think MDF would stand up as the forming shape or is it necessary to use metal? I'm just thinking they will be only used once and to produce them in metal is going to take a lot of time. I see you have used steel, but if I must use metal, would aluminium be OK as it is much easier to cut and file to shape? Bob. Hi Bob, I don't think MDF would survive, even Aluminium might be a bit soft. It may be ok though since the radii are quite large.
|
|
|
Post by 92220 on Jun 22, 2019 15:01:17 GMT
Thanks Roger. I'll give MDF a miss but try aluminium, and hope it works. It's only a one-use former so hopefully it will stand up to forming the brass to a 12.5mm radius.
Bob.
|
|
|
Post by Roger on Jun 22, 2019 17:01:46 GMT
Thanks Roger. I'll give MDF a miss but try aluminium, and hope it works. It's only a one-use former so hopefully it will stand up to forming the brass to a 12.5mm radius. Bob. It helps to make a plate that's in the shape of the flat part which clamps the plate firmly at the start of the bend. In my opinion that's well worth the effort because it saves deforming that area, only too have to try to get it flat again. Forming the bend always deforms the area before where the bend starts unless you take steps to prevent it.
|
|
|
Post by ettingtonliam on Jun 22, 2019 17:50:54 GMT
100 %.
|
|
|
Post by 92220 on Jun 22, 2019 17:55:21 GMT
Thanks Roger. I'll give MDF a miss but try aluminium, and hope it works. It's only a one-use former so hopefully it will stand up to forming the brass to a 12.5mm radius. Bob. It helps to make a plate that's in the shape of the flat part which clamps the plate firmly at the start of the bend. In my opinion that's well worth the effort because it saves deforming that area, only too have to try to get it flat again. Forming the bend always deforms the area before where the bend starts unless you take steps to prevent it. Hi Roger. Thanks for that suggestion. I had noted that you had made up a clamping plate when you did your forming so I was going to sort out how to do it as well. I can fully understand the logic behind your suggestion. Bob.
|
|
|
Post by jon38r80 on Jun 23, 2019 11:16:12 GMT
Sheet metal tends to get fatigue cracking when its mounted on a rigid point and subject to flexing ( Hand brake mountings on a 2CV parcel shelve is how I found out, pulled on the brake one day and the whole thing just pulled out in my hand. the shelf being the thin metal sheet and the handbrake bracket very stiff.) so maybe the wood block allows a little flexing in the sheet metal over a larger area so you get less of a stress line.
|
|
jem
Elder Statesman
Posts: 1,065
|
Post by jem on Jun 23, 2019 16:22:03 GMT
Wonderful car the 2cv, but what do you want a hand brake for, they never worked did they!!!
Jem
|
|