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You can teach a new dog old tricks (or is that the other way around??).
Over the past 2 years we have been experimenting with bettering the Accucraft GS-4's. The final culmination of our efforts for either version (gas or alcohol) was the working Combination lever kit, developed and produced by Gordon Watson of Argyle Locomotive Works. In addition to installing the kits, I have been making the smaller bells and whistles, so to speak, that allow convience in operating this now transformed engine. There are many photos in this post, so dial-up beware!
Here is a general overview of the cab of a gas fired GS-4 with various trinkets attached:
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Most notable to the untrained eye is the extension of the throttle valve outside the cab, along with the addition of a globe valve in place of the "whistle lever" that is used to heat the gas tank bath:
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Recently, I have been researching ways to free up some more steam flow to allow a higher speed at lower throttle and high cut-off percentage. In layman's terms, I was opening up the exhaust passages.
Using simple turnings and brass stock, I created a height adaptor (solid round piece with threads on either end) and a exhaust nozzle done to the G1MRA 3:1 stack ratio. All were bored to a 2mm passage (same as the main exhaust line from the cylinders.
Shown here is the stock "chuff pipe" (Right) and the newly designed nozzle and corresponding height/thread adaptor (Left):
**Note, Gas Fired engines only, since the alcohol fired GS-4's get new blower and exhaust nozzles as part of the combination lever kit**
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A closer view of the new exhaust parts:
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With the Asthma problem half way cured (short of boring all the passages in the locomotive, I was going for ease of install), It was time to move on to being able to control the engine on the fly without hazarding yourself by opening the cab roof and accidentaly hitting something, which can ruin your day. Also, after seeing three GS-4's that came throught the shop without the backplate on the cab (weakens all the other parts of the cab, eventually needing re-soldering), I needed to design a piece that would allow the owner to retain structural integrity.
Once again , I turned to my lathe and half baked brain. The throttle extension shown here is my own design, but they all work on the same principle. A hole in one end to slip over the OEM throttle, with a set screw to hold it in place, while the other end is finished off with the necessary diameter needed to re-attach the stock plastic knobby thingy:
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The only thing that needs to be modified for the extenstion to fit is removing the deckplate on the back of the cab wall.
The next image shows copies I've made of Gordon Watson's extensions, specifically used on the alcohol fired GS's (the LH one is for the blower, RH for the throttle):
![]()
A photo of the above extensions on our alcohol fired GS-4:
![]()
There were two other items that needed to be addressed before I could give this engine it's road trials.
First, the side rods have a extremely poor lap joint (similar to the first run C-16's), creating quite a bit of slop and clanking, creating premature wear on the rod bearings. Following Larry Herget's (highpressure) suggetsion, the pins were brazed to the outer rods connecting the 1st and 4th driver to the 2nd and 3rd respectively. See the Informative threads index, here Here is a quick photo:
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For those wanting to equip their engine with any of the above mentioned items, please contact me off list. (end plug for my services)
In the next installment, I will cover the rebuilding of the water feed system, along with items that apply only to the Alcohol fired version of the GS-4.
Over the past 2 years we have been experimenting with bettering the Accucraft GS-4's. The final culmination of our efforts for either version (gas or alcohol) was the working Combination lever kit, developed and produced by Gordon Watson of Argyle Locomotive Works. In addition to installing the kits, I have been making the smaller bells and whistles, so to speak, that allow convience in operating this now transformed engine. There are many photos in this post, so dial-up beware!
Here is a general overview of the cab of a gas fired GS-4 with various trinkets attached:
Most notable to the untrained eye is the extension of the throttle valve outside the cab, along with the addition of a globe valve in place of the "whistle lever" that is used to heat the gas tank bath:
Recently, I have been researching ways to free up some more steam flow to allow a higher speed at lower throttle and high cut-off percentage. In layman's terms, I was opening up the exhaust passages.
Using simple turnings and brass stock, I created a height adaptor (solid round piece with threads on either end) and a exhaust nozzle done to the G1MRA 3:1 stack ratio. All were bored to a 2mm passage (same as the main exhaust line from the cylinders.
Shown here is the stock "chuff pipe" (Right) and the newly designed nozzle and corresponding height/thread adaptor (Left):
**Note, Gas Fired engines only, since the alcohol fired GS-4's get new blower and exhaust nozzles as part of the combination lever kit**
A closer view of the new exhaust parts:
With the Asthma problem half way cured (short of boring all the passages in the locomotive, I was going for ease of install), It was time to move on to being able to control the engine on the fly without hazarding yourself by opening the cab roof and accidentaly hitting something, which can ruin your day. Also, after seeing three GS-4's that came throught the shop without the backplate on the cab (weakens all the other parts of the cab, eventually needing re-soldering), I needed to design a piece that would allow the owner to retain structural integrity.
Once again , I turned to my lathe and half baked brain. The throttle extension shown here is my own design, but they all work on the same principle. A hole in one end to slip over the OEM throttle, with a set screw to hold it in place, while the other end is finished off with the necessary diameter needed to re-attach the stock plastic knobby thingy:
The only thing that needs to be modified for the extenstion to fit is removing the deckplate on the back of the cab wall.
The next image shows copies I've made of Gordon Watson's extensions, specifically used on the alcohol fired GS's (the LH one is for the blower, RH for the throttle):
A photo of the above extensions on our alcohol fired GS-4:
There were two other items that needed to be addressed before I could give this engine it's road trials.
First, the side rods have a extremely poor lap joint (similar to the first run C-16's), creating quite a bit of slop and clanking, creating premature wear on the rod bearings. Following Larry Herget's (highpressure) suggetsion, the pins were brazed to the outer rods connecting the 1st and 4th driver to the 2nd and 3rd respectively. See the Informative threads index, here Here is a quick photo:
For those wanting to equip their engine with any of the above mentioned items, please contact me off list. (end plug for my services)
In the next installment, I will cover the rebuilding of the water feed system, along with items that apply only to the Alcohol fired version of the GS-4.
