# Why cant Accucraft make a throttle valve that is tame?



## Mike Toney (Feb 25, 2009)

Not to remove sales from those that make replacements, but why after all this time.are they not able to produce or even copy one of the better aftermarket throttles and eliminate this ongoing issues with thier engines. Seems like every model runs like a jack rabbit out of the box. For what we spend on these engines, and the mass quantiies this company is selling, I personaly feel its unacceptable to have to buy an aftermarket throttle valve to tame the slow speed running. I am sure some will say it will add expense to the model, but when your at the $2000+ point, its a drop in the bucket so to speak. While I love Fairymead, the whole issue having to clean up burrs in the slot for the trailing truck and either wait for new springs and deal with that tear down or purchase/make a spacer for the trailing truck to correct a flaw. Why wasnt this caught on the prototype when it was here in the states running, or did the Chinese pull another fast one and use cheaper/lighter weight springs in production or change a design specification? For what my friend spent, these issues shouldn't happen. Mike


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## Dr Rivet (Jan 5, 2008)

Mike

I have the new SP Mogul from Accucraft. It has great throttle control even at sustained low speeds. My SP F4 ran fine out of the box. The little British B4 0-4-0T dock tank OTOH, is a PITA to get the gas adjusted and has only fair throttle control unless it has a noticeable load behind it. 

Many folks have Aster locomotives that exhibit the same characteristics... 

Live steam has ALWAYS been a hobby for tinkerers. If you want perfect out of the box performance every time... go buy an electric locomotive made by USAT or LGB and improve your chances.

I don't expect things to change in my life time.


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## Nick Jr (Jan 2, 2008)

Jim, I do prefer to tinker with my locomotives myself, as it was expressed to me, "most would rather spend $$ than effort, no matter how easy it is". 
Mike, as I have mentioned in a prior post, why have most all of my previous Accucraft locomotives came with a pinched exhaust pipe and the new Fairy is wide open?? 
I made mine the same, without an additional purchase and it is much cleaner and the plumes are just the same.


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## Pete Thornton (Jan 2, 2008)

Mike Toney said:


> Not to remove sales from those that make replacements, but why after all this time.are they not able to produce or even copy one of the better aftermarket throttles and eliminate this ongoing issues with thier engines. Seems like every model runs like a jack rabbit out of the box. For what we spend on these engines, and the mass quantiies this company is selling, I personaly feel its unacceptable to have to buy an aftermarket throttle valve to tame the slow speed running. I am sure some will say it will add expense to the model, but when your at the $2000+ point, its a drop in the bucket so to speak. While I love Fairymead, the whole issue having to clean up burrs in the slot for the trailing truck and either wait for new springs and deal with that tear down or purchase/make a spacer for the trailing truck to correct a flaw. Why wasnt this caught on the prototype when it was here in the states running, or did the Chinese pull another fast one and use cheaper/lighter weight springs in production or change a design specification? For what my friend spent, these issues shouldn't happen. Mike


Mike,
The larger, heavier locos do not have a throttle problem, in my experience. However, putting the same throttle in a light, small loco does produce the problem you describe!


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## Mike Toney (Feb 25, 2009)

Maybe because it seems most folks now put either a Summerlands chuff pipe or make thier own. That is interesting that they havent been pinching the pipe off lately. The Jury is still out on my Fairymead on how touchy it is as till my line is rebuilt I cant do more than run it back and fourth. Emma is pretty controlable but it had RC already installed so I can deal with it as well. I can say from having run NKP 587 in real life a few years ago, even real ones take some (Fiddling with the throttle) to get them rolling. Pull it way out to get her to start to move, but dont pull it so far as to spin the drivers, then close it back down so as not to exceeded yard speed. I seem to notice the touchy throttle more in manual controled engines over an RC one. My guess its the real time control RC gives me verses getting my fat fingers in the cab and trying to "notch" the throttle gradualy, which usualy doesnt happen most likely. And I do have electric ones, for when I dont have the time to run live steam.


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## Nick Jr (Jan 2, 2008)

Mike, I think when you install the R/C on the throttle you will see how little movement it really takes to tame the locomotive. Manually you can only adjust it when it is within arms reach, with R/C you can make infinite adjustments and even when you can't reach it. I've found that all locomotives really don't need Fwd/Rev remote, some of mine only have throttle control. Each to his own.


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## Mike Toney (Feb 25, 2009)

That is what I sort of said in my last post. My Emma, which has RC, is much more controlable at slow speeds and is less "touchy" than Fairymead or other manual engines I have owned/operated. The real time ablity to control the throttle, like your in the cab in 1:1 scale steamers, is more the key to slow speed. But, some folks like thier engines manual, so a better factory throttle valve would be nice. I am just supprise with how the Chinese love to copy designs, that they havent cloned one of the aftermarket throttles into thier stock production runs. Mike


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## Chris Scott (Jan 2, 2008)

Dave Hottmann came up with a solution for eliminating the free play in the throttle. He put a spring on the throttle shaft which maintained tension on the shaft. Works really well. I suppose you could do the same to the gas valve but it didn't ever seem to need it.


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## Steve Ciambrone (Feb 25, 2014)

Roundhouse engines have a spring on the gas valve for the same reason.

Steve


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## Kovacjr (Jan 2, 2008)

Mike Toney said:


> Not to remove sales from those that make replacements, but why after all this time.are they not able to produce or even copy one of the better aftermarket throttles and eliminate this ongoing issues with thier engines. Mike


 
Ive run the Fairymead in particular this weekend and with no load too. It ran just fine with a slight throttle opening and was very controllable. The propose of the coarser throttle from the factory is to compensate for the Manual AND RC control as with my the finer spindle I offer you need to open the throttle more to get to the same opening as the less tapered.

I also ran the loco as a sample for many months as it was my project to look over and myself and anyone that did run it including fomr MLS members had no issues with throttle control.

Really has nothing to do with cost. 

As to the comment of just copy some other one, most business operate with standards and morals and do not copy other people things ideas, though there are some out there that do!

Chris I think you have it reversed as Dave puts the springs on the gas valves to loose the Oring tension same as Roundhouse. I dint that a lil Vaselene also does the trick with the gas spindle Orings


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## Chris Scott (Jan 2, 2008)

Kovacjr said:


> Chris I think you have it reversed as Dave puts the springs on the gas valves to loose the Oring tension same as Roundhouse. I dint that a lil Vaselene also does the trick with the gas spindle Orings


Jason;
Dave installed throttle springs on two of my locos while tuning them; K-27 and 3 Cyl. Shay. At the time he made no mention of the need nor did he suggest a spring on the gas valve. This was some time ago. I've installed spring on other locos all with good results. Still have not found a reason, free play or burner behavior, for a spring on the gas valve. Haven't talked to Dave in awhile so I don't know his views.


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## Charles M (Jan 2, 2008)

I have used a light spring on the gas valve for a few years now. It prevents "creep" of the position you have set on the burner control. Some of mine seem to be touchier than others in this regard.

Charles M SA#74


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## Chris Scott (Jan 2, 2008)

_
Only thing I can think is that some locos are creepier than others.

 _


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## Charles M (Jan 2, 2008)

Creepier is better at Halloween . 

Charles M SA#74


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## jfrank (Jan 2, 2008)

I have never had any problem with Accucraft throttle valves. There's are better than Asters. Slow speed running is easy.


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## Nick Jr (Jan 2, 2008)

John,I can't testify to the Aster, but as far as Accucraft, I've never had creep with either the throttle or gas valves no matter what lubricant I put on the O rings.
The after market throttle valves will add more rotation to the throttle than the factory provided valve for equal steam delivery, so a standard rod operation of the servo will have to be replaced with a more expensive chain and sprocket device. Since I have tried them both I know the difference.


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## Nick Jr (Jan 2, 2008)

Forgot to mention yesterday. Several years ago I read somewhere (probably a forum) that the use of O ring lubricant used on swimming pools will keep our O rings from drying and cracking. 
I was skeptical since our locomotives get much hotter than pool equipment, but tried it and it does work. It is also viscus enough to keep the setting right where you leave it. Tiny jar of it was just a few $$ and I have a life time supply.


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## Chris Scott (Jan 2, 2008)

Nick;
Name of pool lube?


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## Ray Cadd (Dec 30, 2008)

I too have never had a problem with Accucraft throttles (exception-Ruby, although that's more an issue of general design), and I've owned quite a few, including the Fairymead, which I find quite controllable. My personal experience is, they just need a bit of finesse. Jason's aftermarket valve spindle helps quite a bit, by increasing the bandwidth of adjustment. 

As a suggestion, one thing I always do is lose the factory knob and replace with an extended 90 degree handle or lever, if you will. The longer reach of that lever will also give you finer control, and is an easy fit.


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## Nick Jr (Jan 2, 2008)

Chris I'll have to go to the same store tomorrow and get the information from the counter man. the little container I have has shed the label a while ago. Tune in tomorrow and I will post all the info.

Ray, Accucraft has replaced both the throttle and most of the gas knobs with levers for some time now. Did your Fairymead come with knobs??


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## Nick Jr (Jan 2, 2008)

Chris, I just couldn't wait till tomorrow. 
Went to the pool store, the stuff I bought years ago was called Magic Lube, but they don't carry it any more, not to say it isn't available at other locations. They now sell Lube Tube. I asked for a cut sheet on both materials, not available but their computer said it is good up to 500'F which is a bit more than our boilers get. 
I must comment, the new product doesn't seem as viscus as the Magic Lube. 
Best I can do at this time. Hope it helps you. I bought a tube if it so I now have enough to last two life times.


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## StackTalk (May 16, 2014)

You may wish to consider Molykote 111 or Molykote 112

I haven't used 112 but it does go to 450F whereas 111 is rated to 400F

I use 111 and I recently compared notes with someone who has built numerous live steam locomotives commercially and coincidentally, he uses Molykote 111 as well. It can be purchased through Amazon and other places.

Specs for the product line here:

https://www.dowcorning.com/content/publishedlit/80-3256.pdf

Cheers,

Joe


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## Ray Cadd (Dec 30, 2008)

Nick Jr said:


> Chris I'll have to go to the same store tomorrow and get the information from the counter man. the little container I have has shed the label a while ago. Tune in tomorrow and I will post all the info.
> 
> Ray, Accucraft has replaced both the throttle and most of the gas knobs with levers for some time now. Did your Fairymead come with knobs??


Fairymead and Emma are the most recent ones I've owned- been a while since. Yes, you're right, they did come with levers, although rather short. For clarity, I'm talking about levers with about 1.7" or so in length, which should give better fine control. Although, honestly, I left the stock levers on the two aforementioned engines with no problem.


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## redbeard (Jan 2, 2008)

First running at Diamondhead I was advised that SOP was to put a drop of steam oil on the steam valve o-ring. Works well for me since then!
Larry


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