The new Langworthy Hudson trailing truck leaf spring end keepers.
See the first photo which has the original Langworthy keeper on the left (which can flip out), two of the Josslin Hudson keepers in the center and the new Langworthy keepers on the right. They new Langworthy leaf spring end keepers are a lot more work than the originals but then they are "bullet proof".
I first made up a sketch from what I was able to measure from the 4 wheel trailing truck without having to take it all apart (but in the end I had to partially disassemble it - which gave Murphy a good chance to trip me up again - more about this later). I then made a test keeper from the sketches (seen as the upper right keeper) in the first photo. It was close but it wouldn't quite fit as I didn't get all of the needed dimensions without disassembling the truck.
I'll bet you would like to know how those perfect miniature rectangular slots were made for the Josslin Hudson leaf spring end keepers. It is quite easy to do with the right equipment and the right methods. It was described in great detail in the Josslin Hudson construction series. The Josslin Hudson leaf spring end keepers are quite an improvement over the Langworthy keepers and follow exactly the prototype parts but they are not 100% "bullet proof" either.
The second photo shows a new Langworthy keeper in place. One had to partially disassemble the rear of the 4 wheel trailing truck to be able to push the 3/32" dia. drill rod locking pin through the keeper and the leaf spring hanger eye. The trailing truck has 8 end keepers and the engine 24 in total - so it is like a work program if you want to replace all of them.
As I mentioned, Murphy had something to say about this.
A Real Dirty Job
Moderator: Harold_V
Re: A Real Dirty Job
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Re: A Real Dirty Job
As I mentioned previously, Murphy kept urging me to delve into the innards of the trailing truck to see what wonders lay there.
All along, I could see that the rear leaf spring hangers were not in the best of shape so I finally took the rear of the trailing truck apart to have a good look at them.
Actually, after 30 years of use and abuse, they were still operational but in need of replacement as one was nearly worn through in the upper eye area.
The photo shows the exact same part on the Josslin Hudson for comparison. Both the Langworthy and the Josslin Hudson are exactly the same locomotive but the Josslin Hudson parts here are substantially more robust. The upper part of the Langworthy spring hanger is 1/16" thick while on the Josslin it is 3/32" thick. This doesn't seem like much but it will increase the working life of the part.
On my set of Langworthy drawings, the width of the upper spring hanger eye opening is not shown so I made it 3/32" in dia. as the tab width on my Langworthy locomotive is 7/32" vs 9/32" on the Josslin (which has a 1/8" eye opening). Also, the lower rectangular box section of the Langworthy spring hanger is 1/8" thick vs 5/32" thick on the Josslin spring hanger.
I will use the Josslin design for the rebuild (except for the upper eye opening as mentioned) as heavier/thicker is better in this case. I suspect that the spring hanger parts on the Langworthy may have been simply scaled down from the prototype but as I don't build scale models only detailed working models - there is a big difference.
So, after the rebuild, someone 50 years from now can replace them again but it won't be ... as they are made from plain hot rolled steel.
Actually, if you want to make them really "bullet proof" they could be made from 01 or gauge stock and hardened and tempered after machining. But expect twice the HSS end mill wear machining these materials even in the annealed state.
All along, I could see that the rear leaf spring hangers were not in the best of shape so I finally took the rear of the trailing truck apart to have a good look at them.
Actually, after 30 years of use and abuse, they were still operational but in need of replacement as one was nearly worn through in the upper eye area.
The photo shows the exact same part on the Josslin Hudson for comparison. Both the Langworthy and the Josslin Hudson are exactly the same locomotive but the Josslin Hudson parts here are substantially more robust. The upper part of the Langworthy spring hanger is 1/16" thick while on the Josslin it is 3/32" thick. This doesn't seem like much but it will increase the working life of the part.
On my set of Langworthy drawings, the width of the upper spring hanger eye opening is not shown so I made it 3/32" in dia. as the tab width on my Langworthy locomotive is 7/32" vs 9/32" on the Josslin (which has a 1/8" eye opening). Also, the lower rectangular box section of the Langworthy spring hanger is 1/8" thick vs 5/32" thick on the Josslin spring hanger.
I will use the Josslin design for the rebuild (except for the upper eye opening as mentioned) as heavier/thicker is better in this case. I suspect that the spring hanger parts on the Langworthy may have been simply scaled down from the prototype but as I don't build scale models only detailed working models - there is a big difference.
So, after the rebuild, someone 50 years from now can replace them again but it won't be ... as they are made from plain hot rolled steel.
Actually, if you want to make them really "bullet proof" they could be made from 01 or gauge stock and hardened and tempered after machining. But expect twice the HSS end mill wear machining these materials even in the annealed state.
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Re: A Real Dirty Job
Two new front leaf spring hangers roughed out for the four wheel trailing truck. Endless milling work here.
In my previous posts where I referred to the "rear" spring hangers (on the truck rear leaf springs), it should be the "front" spring hangers (on the truck front leaf springs). There is a front spring hanger and a rear spring hanger on the front truck set of leaf springs and they are both different to each other. And, there is a front spring hanger and a rear spring hanger on the rear set of truck leaf springs and they are both different to each other and also to both of the front leaf spring hangers. Really confusing.
In my previous posts where I referred to the "rear" spring hangers (on the truck rear leaf springs), it should be the "front" spring hangers (on the truck front leaf springs). There is a front spring hanger and a rear spring hanger on the front truck set of leaf springs and they are both different to each other. And, there is a front spring hanger and a rear spring hanger on the rear set of truck leaf springs and they are both different to each other and also to both of the front leaf spring hangers. Really confusing.
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Re: A Real Dirty Job
The next operation was to mill out the two internal spring hanger slots. One was 3/32" dia. by 3/16" long and the other was 1/8" dia. by 1/4" long.
These slots need to be central.
Do the layout work first. See the first photo.
As the rough spring hanger blanks were left 1/32" oversize on length width and thickness, the layout lines were adjusted to accommodate this.
Drill out as much material inside the slot as possible without going over the layout lines. To do this use good lighting, an eye loupe and initially, a small center drill. One can deviate a bit from central as the oversize blank width allows for this. I always leave the work blank oversize when slots needing to be central are involved.
Then, the drilled holes were turned into a slot first with a 3/32" dia. end mill followed by a 1/8" dia. end mill on the spring hanger cross beam ends (the thicker end).
Set the mill's table stops as an aid to be able to mill just up to the layout lines. Again, use good lighting and an eye loupe to set the table stops.
This milling operation is delicate and fussy so don't be in a hurry. I limited the depth of cut to 0.005" - 0.010" per pass.
Digital would definitely help but then I am used to my obsolete manual ways.
The rounded ends of the cross beam slots will be squared next.
These slots need to be central.
Do the layout work first. See the first photo.
As the rough spring hanger blanks were left 1/32" oversize on length width and thickness, the layout lines were adjusted to accommodate this.
Drill out as much material inside the slot as possible without going over the layout lines. To do this use good lighting, an eye loupe and initially, a small center drill. One can deviate a bit from central as the oversize blank width allows for this. I always leave the work blank oversize when slots needing to be central are involved.
Then, the drilled holes were turned into a slot first with a 3/32" dia. end mill followed by a 1/8" dia. end mill on the spring hanger cross beam ends (the thicker end).
Set the mill's table stops as an aid to be able to mill just up to the layout lines. Again, use good lighting and an eye loupe to set the table stops.
This milling operation is delicate and fussy so don't be in a hurry. I limited the depth of cut to 0.005" - 0.010" per pass.
Digital would definitely help but then I am used to my obsolete manual ways.
The rounded ends of the cross beam slots will be squared next.
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Re: A Real Dirty Job
Producing square ended miniature slots from rounded end slots.
It is all about the setup and the tooling needed (and the tooling needed to produce the tooling).
I have two separate ways of doing the above. One of which I pioneered (as I have never seen it described anywhere - other than in my Josslin Hudson construction series) uses a commercial 1/8" square broach as seen in the first photo (very expensive) and multiple copper shims to broach the end of the slot square and the second method, favoured by Harold, which is to grind up a special slotting cutter from a piece of round HSS (miniature in my case) and to use the quill of the milling machine to slot the end of the slot. To do this one really needs a lever operated quill and not the handwheel which I have on the Millrite so I don't use this machine for any slotting work.
Of course if one has a slotting attachment (like one can get for the Bridgeport milling machine), the job is made considerably easier but since I have nothing like this...
I am very fortunate to have a surface grinder and this was used to make the special HSS miniature special slotting cutter - I am hopeless to do it by hand.
The attached photos show the machines and tooling needed to do the job both ways. I must say that the cheap bench arbor press shown in the first photo has been considerably modified to turn it into a semi precision broaching press which is a whole other topic in itself and will not be dealt with here.
The second photo shows the overall tooling and the tooling which will be used to hold the special slotting cutter blank for the SG. This photo also shows a couple of examples of the special miniature slotting cutters made for other jobs but unfortunately they are not the right size or shape for the job at hand.
There is a lot more to this than just the tooling - the setup is very critical as well as everything has to be aligned dead square and central. Stay tuned.
It is all about the setup and the tooling needed (and the tooling needed to produce the tooling).
I have two separate ways of doing the above. One of which I pioneered (as I have never seen it described anywhere - other than in my Josslin Hudson construction series) uses a commercial 1/8" square broach as seen in the first photo (very expensive) and multiple copper shims to broach the end of the slot square and the second method, favoured by Harold, which is to grind up a special slotting cutter from a piece of round HSS (miniature in my case) and to use the quill of the milling machine to slot the end of the slot. To do this one really needs a lever operated quill and not the handwheel which I have on the Millrite so I don't use this machine for any slotting work.
Of course if one has a slotting attachment (like one can get for the Bridgeport milling machine), the job is made considerably easier but since I have nothing like this...
I am very fortunate to have a surface grinder and this was used to make the special HSS miniature special slotting cutter - I am hopeless to do it by hand.
The attached photos show the machines and tooling needed to do the job both ways. I must say that the cheap bench arbor press shown in the first photo has been considerably modified to turn it into a semi precision broaching press which is a whole other topic in itself and will not be dealt with here.
The second photo shows the overall tooling and the tooling which will be used to hold the special slotting cutter blank for the SG. This photo also shows a couple of examples of the special miniature slotting cutters made for other jobs but unfortunately they are not the right size or shape for the job at hand.
There is a lot more to this than just the tooling - the setup is very critical as well as everything has to be aligned dead square and central. Stay tuned.
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Re: A Real Dirty Job
Squaring the spring hanger cross beam slots.
I used my Dore Westbury bench mill for this purpose as it has a rack and pinion lever operated quill (as well as a fine feed hand wheel).
I have not described this method before so here it is.
To begin with, the mill fought me all the way to the bitter end today (one of those days). The method produces excellent results but preparation and care are everything. That is why I developed an alternative broaching method. However, one can have just as many issues with it. The broaching method has been described, in detail, in my Josslin Hudson construction series.
Before you even start,
The spindle of the mill has to be set dead square to the table, the holding vise jaws have to be indicated dead square on the table, the vise jaws have to be ground or new without any nicks or bumps, the mill's spindle has to have a very positive locking feature (I can lock the spindle on the DW 180 degrees apart), a rack and pinion quill, etc., etc. - it goes on and on.
The first photo shows the overall setup. One can see the extended lever operated quill handle arm and the extended spindle locking pin (used for illustration only).
The first real operation is to set the slotting tool cutting edge dead square to the rear vise jaw as seen in the second photo. Hold the slotting tool in the collet very lightly as pliers are needed on the round shank of the tool to rotate it very slightly as needed. Use very good lighting and an eye loupe to just brush past the top edge of the rear vise jaw. Also, the slotting tool has to be extended out so that it will pass down through the top clamp of the spring hanger holding fixture and just a little more than the full depth of the part.
Once the tool has been set, carefully tighten the collet (I also had to tighten the mill's column) and check again that that the cutting tool has not rotated or moved.
The third photo shows the part holding fixture base now in the vise and the spring hanger blank set in it without the top clamp. The cross slide is moved until the slotting tool just passes down into the spring hanger slot without being offset on either side or fouling the tool on the rounded ends of the slot. One uses delicate "feel" here. Lock the cross slide of the mill securely. The base of the spring hanger holding fixture has a hole drilled in the centre of the fixture slot to allow the cutting end of the slotting bit to pass down into it.
The fourth photo shows the slotting operation itself with the holding fixture top clamp in place. Be very careful that the part does not move or rotate at all when clamping as slotting success depends upon the spring hanger being dead aligned along one side of the slot in the holding fixture base. This is where I had an issue as it is very difficult to see if the part is truly square in the holding fixture or not. Ensure that the top clamp holds the part securely.
One should note that the round shank of the slotting tool is larger than the cutting end of the tool bit so one can run into the side of the forked holding clamp before the cutting edge of the tool has finished squaring the slot corner so check before you cut. I didn't and...
For actual slotting, move the table ever so slightly forward at each stroke. The tool is a shaving tool so minute cuts are in order. The tool will tell you quickly enough. Start the tool as far back from the corner as possible as there is hardly any room to manoeuvre at all with these miniature slots.
The last two photos shows what is possible.
I used my Dore Westbury bench mill for this purpose as it has a rack and pinion lever operated quill (as well as a fine feed hand wheel).
I have not described this method before so here it is.
To begin with, the mill fought me all the way to the bitter end today (one of those days). The method produces excellent results but preparation and care are everything. That is why I developed an alternative broaching method. However, one can have just as many issues with it. The broaching method has been described, in detail, in my Josslin Hudson construction series.
Before you even start,
The spindle of the mill has to be set dead square to the table, the holding vise jaws have to be indicated dead square on the table, the vise jaws have to be ground or new without any nicks or bumps, the mill's spindle has to have a very positive locking feature (I can lock the spindle on the DW 180 degrees apart), a rack and pinion quill, etc., etc. - it goes on and on.
The first photo shows the overall setup. One can see the extended lever operated quill handle arm and the extended spindle locking pin (used for illustration only).
The first real operation is to set the slotting tool cutting edge dead square to the rear vise jaw as seen in the second photo. Hold the slotting tool in the collet very lightly as pliers are needed on the round shank of the tool to rotate it very slightly as needed. Use very good lighting and an eye loupe to just brush past the top edge of the rear vise jaw. Also, the slotting tool has to be extended out so that it will pass down through the top clamp of the spring hanger holding fixture and just a little more than the full depth of the part.
Once the tool has been set, carefully tighten the collet (I also had to tighten the mill's column) and check again that that the cutting tool has not rotated or moved.
The third photo shows the part holding fixture base now in the vise and the spring hanger blank set in it without the top clamp. The cross slide is moved until the slotting tool just passes down into the spring hanger slot without being offset on either side or fouling the tool on the rounded ends of the slot. One uses delicate "feel" here. Lock the cross slide of the mill securely. The base of the spring hanger holding fixture has a hole drilled in the centre of the fixture slot to allow the cutting end of the slotting bit to pass down into it.
The fourth photo shows the slotting operation itself with the holding fixture top clamp in place. Be very careful that the part does not move or rotate at all when clamping as slotting success depends upon the spring hanger being dead aligned along one side of the slot in the holding fixture base. This is where I had an issue as it is very difficult to see if the part is truly square in the holding fixture or not. Ensure that the top clamp holds the part securely.
One should note that the round shank of the slotting tool is larger than the cutting end of the tool bit so one can run into the side of the forked holding clamp before the cutting edge of the tool has finished squaring the slot corner so check before you cut. I didn't and...
For actual slotting, move the table ever so slightly forward at each stroke. The tool is a shaving tool so minute cuts are in order. The tool will tell you quickly enough. Start the tool as far back from the corner as possible as there is hardly any room to manoeuvre at all with these miniature slots.
The last two photos shows what is possible.
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Re: A Real Dirty Job
More Murphy!
With the new front spring hangers now being slightly heavier and thicker than the original Langworthy spring hangers, I found that the spring hanger tongues would not readily pass through the slotted ends of the spring assemblies.
This meant getting the spring assemblies out and opening up the slotted ends slightly. This meant taking the four wheel trailing truck further apart. This meant removing more fasteners which of course were totally corroded and would not budge. This meant taking a hacksaw blade by hand and cutting away the nutted end while trying not to touch the frame castings. I spent hours....
Then, it was necessary to remove more of the existing spring hanger retention clips. Some just flipped out and some just wouldn't come out no matter what I did. There may be some technique to remove them easily but I certainly didn't figure it out. Again, I spent hours...
The leaf spring assemblies were absolutely filthy with goo and dried oil mixed in with corrosion products. The original slotting of the leaf spring ends were not perfect as I guess the original builder did not have access to the carbide cutting tools used today. This is one of the few places where I use carbide. The carbide end mill did an excellent job of producing the new slightly larger slots in the hardened blue tempered spring steel.
After this re-assembly of the suspension parts went smoothly. Hopefully, this completes the re-building of the four wheel trailing truck.
With the new front spring hangers now being slightly heavier and thicker than the original Langworthy spring hangers, I found that the spring hanger tongues would not readily pass through the slotted ends of the spring assemblies.
This meant getting the spring assemblies out and opening up the slotted ends slightly. This meant taking the four wheel trailing truck further apart. This meant removing more fasteners which of course were totally corroded and would not budge. This meant taking a hacksaw blade by hand and cutting away the nutted end while trying not to touch the frame castings. I spent hours....
Then, it was necessary to remove more of the existing spring hanger retention clips. Some just flipped out and some just wouldn't come out no matter what I did. There may be some technique to remove them easily but I certainly didn't figure it out. Again, I spent hours...
The leaf spring assemblies were absolutely filthy with goo and dried oil mixed in with corrosion products. The original slotting of the leaf spring ends were not perfect as I guess the original builder did not have access to the carbide cutting tools used today. This is one of the few places where I use carbide. The carbide end mill did an excellent job of producing the new slightly larger slots in the hardened blue tempered spring steel.
After this re-assembly of the suspension parts went smoothly. Hopefully, this completes the re-building of the four wheel trailing truck.
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Re: A Real Dirty Job
The rebuilt Langworthy Hudson 4 wheel trailing truck.
It was an indescribable nightmare to get the truck completely back together again. I tried about 6 different ways and nothing worked until, in desperation, I simply guessed something which did work. There is so little room to put and align the suspension parts inside the frame casting and they need to be canted to get them in and when you do that they jam up.
There is only one way to put the truck innards suspension system back together and it is not at all obvious. I hope I remember...
The truck could still use a thorough high pressure steam cleaning or as an alternative take it completely apart again and bead blast all of the parts to clean them. Both truck equalizer arms were frozen solid with corrosion and someone in his wisdom had, on the equalizer pivot bearings, jammed in threaded fasteners. Really...
Again, can I say use an anti seize compound on any and all locomotive fasteners. If you are worried about them coming apart or loose then cross drill the fastener and wire lock them as is done with piston aero engines or very lightly raise an edge burr to lock them with a blind hole.
It was an indescribable nightmare to get the truck completely back together again. I tried about 6 different ways and nothing worked until, in desperation, I simply guessed something which did work. There is so little room to put and align the suspension parts inside the frame casting and they need to be canted to get them in and when you do that they jam up.
There is only one way to put the truck innards suspension system back together and it is not at all obvious. I hope I remember...
The truck could still use a thorough high pressure steam cleaning or as an alternative take it completely apart again and bead blast all of the parts to clean them. Both truck equalizer arms were frozen solid with corrosion and someone in his wisdom had, on the equalizer pivot bearings, jammed in threaded fasteners. Really...
Again, can I say use an anti seize compound on any and all locomotive fasteners. If you are worried about them coming apart or loose then cross drill the fastener and wire lock them as is done with piston aero engines or very lightly raise an edge burr to lock them with a blind hole.
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Re: A Real Dirty Job
Moving right along- the Langworthy Hudson lead truck as it exists today.
You can see it has not had a particularly happy life. The right rear of the frame casting was broken off at some point and was subsequently brazed together again.
The brazing repair got the truck working again but the brazing looked as ugly as sin. I did some work on it previously to smooth out the lumps and bumps to regain the frame profile contour. Still have a bit of finishing to do there.
The original leaf spring assemblies are missing as someone has substituted two rather crude coil springs in their place . It works as is but I will bring back the original leaf springs.
There are no brake details as seen in the Langworthy drawings and I will add them also. The lead truck brake cylinder/links are also missing even though the very detailed Langworthy casting includes the brake cylinder mounting beam and bracket. Bill Shields says that all of this detail just adds clutter and impedes the practical operation of the locomotive when running so I will remove it for track operation if this proves to be the case.
I am also including a photo of the Josslin Hudson lead truck complete frame as I constructed it some time ago for comparison. The Josslin lead truck frame is built up from solid stock by silver soldering versus the very fine casting supplied with the Langworthy. Both lead trucks are very detailed.
There are some differences between the two as to how they are constructed and function. I should have completed the Josslin lead truck years ago and will do it in conjunction the the Langworthy lead truck rebuild. One of my least favourite jobs is to make new axleboxes for the Josslin which are a two piece assembly complete with cellars as per the originals. Lots of fun and you had better get it right work coming up.
For those who are interested, the detailed construction of the Josslin lead truck frame is to be found in my Chaski construction threads "Constructing the Josslin Hudson" and "A Peak at the Josslin Lead Truck".
You can see it has not had a particularly happy life. The right rear of the frame casting was broken off at some point and was subsequently brazed together again.
The brazing repair got the truck working again but the brazing looked as ugly as sin. I did some work on it previously to smooth out the lumps and bumps to regain the frame profile contour. Still have a bit of finishing to do there.
The original leaf spring assemblies are missing as someone has substituted two rather crude coil springs in their place . It works as is but I will bring back the original leaf springs.
There are no brake details as seen in the Langworthy drawings and I will add them also. The lead truck brake cylinder/links are also missing even though the very detailed Langworthy casting includes the brake cylinder mounting beam and bracket. Bill Shields says that all of this detail just adds clutter and impedes the practical operation of the locomotive when running so I will remove it for track operation if this proves to be the case.
I am also including a photo of the Josslin Hudson lead truck complete frame as I constructed it some time ago for comparison. The Josslin lead truck frame is built up from solid stock by silver soldering versus the very fine casting supplied with the Langworthy. Both lead trucks are very detailed.
There are some differences between the two as to how they are constructed and function. I should have completed the Josslin lead truck years ago and will do it in conjunction the the Langworthy lead truck rebuild. One of my least favourite jobs is to make new axleboxes for the Josslin which are a two piece assembly complete with cellars as per the originals. Lots of fun and you had better get it right work coming up.
For those who are interested, the detailed construction of the Josslin lead truck frame is to be found in my Chaski construction threads "Constructing the Josslin Hudson" and "A Peak at the Josslin Lead Truck".
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Last edited by Carrdo on Sun Sep 23, 2018 10:50 pm, edited 4 times in total.
Re: A Real Dirty Job
Pulling the needed material together before even starting. This is a project in itself.
See the block material inside the 3/8" wide by 0.015" thick spring steel strip coil (which was a big shamozzle in itself to get it). It is true Meehanite cast iron which is absolutely the best material for small axle boxes. Just try to find it and then try to get it in small workshop quantities.
And the photo shows what will be required for making only the major lead truck parts.
See the block material inside the 3/8" wide by 0.015" thick spring steel strip coil (which was a big shamozzle in itself to get it). It is true Meehanite cast iron which is absolutely the best material for small axle boxes. Just try to find it and then try to get it in small workshop quantities.
And the photo shows what will be required for making only the major lead truck parts.
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Re: A Real Dirty Job
After slicing off lengths of spring steel from the parent roll, grinding the ends square and to length.
I used my 7" bench grinder and a 1/16" thick fine abrasive cutoff wheel for the above operations.
As all of this is hand held work, don't be too aggressive with the wheel as the spring steel will get hot very quickly (use a light feed with a firm grip). The pieces of spring steel can also act like flying razor blades if you snag them on the wheel with too aggressive a feed.
I used my 7" bench grinder and a 1/16" thick fine abrasive cutoff wheel for the above operations.
As all of this is hand held work, don't be too aggressive with the wheel as the spring steel will get hot very quickly (use a light feed with a firm grip). The pieces of spring steel can also act like flying razor blades if you snag them on the wheel with too aggressive a feed.
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