# I know, It's nit picking.... but why is it done that way ??



## Steve S. (Jan 2, 2008)

After looking at the pictures of the new Accucraft Mason Bogie along with their other latest offerings such as the 2-10-2 etc., I see how long a ways that Accucraft has come. The fine detail and overall finish is amazing and with the use of axle pumps and other accessories I can see why people are so fond of them. My question is why do they still set up the linkage to the valve gear in reverse of the way that just about everybody else does (including the real steamer's). The radius rod is up in the expansion link for forward and down for reverse. This is backwards. I have heard that other hobby loco makers use a steam reverser plate between the valve chest and cylinder block to achieve this "_correct look " _on some of their designs. I am not a rivet counter by any means. I may also be the only person that has ever noticed this, but I just wonder why ??


----------



## rwjenkins (Jan 2, 2008)

I was wondering about that myself, looking at the Mason Bogie pics. On other engines like the K-27 and the GS-4, the problem is that the models use D-valves, which by definition are outside-admission, while the prototypes had piston valves, which are typically inside-admission. However, on the Mason Bogie, both the model and the prototype had D-valves, so in theory Accucraft's "backwards" valve gear should actually be correct in this case. Apparently not though, looking at prototype photos. The problem in this case is the position of the eccentric crank relative to the wheel center, Accucraft has it backwards. The good news is this should be relatively easy to fix on this model, as opposed to adding cross-ports on the piston-valve prototypes.

A few pics for comparison:


Prototype photo: Notice eccentric crank is aft of the wheel center with rods down.


Accucraft model at Dr. Rivet's: Notice eccentric crank is aft of the wheel center with rods up (rotate wheels 180 degrees to match the prototype photo and the eccentric crank would be ahead of wheel center).

Accucraft model (publicity shot): Position of the eccentric crank appears to actually be correct in this photo, I'm not sure when or why it was changed.


----------



## Dan Rowe (Mar 8, 2009)

To accurately answer any question about valve gear the type of gear should be mentioned. 

However I have an Aster Daylight that uses a reverser plate. The reason the reverser plate is used is because the prototype used piston valves which are inside admission. Piston valves do not really work very well on models because they can not lift off the seat to let water pass when starting out. The Aster Daylight has D slide valves which are outside admission so the reverser plate makes the D slide valve operate like an inside admission valve and the gear looks right in photos.

When the thing is running you can not tell the difference so keep them running.
Cheers Dan


----------



## Charles (Jan 2, 2008)

Steve
I agree with your spot on observation. In particular with SG engines in which Accucraft has only done it correct once in 4 production runs. Especially disappointing with the high ticket SG engines. Why, my guess is that their customer base is more concerned with details/rivet counting regards to appearance than mechanics.


----------



## Kovacjr (Jan 2, 2008)

Accucraft had changed the position of the radius rod to be down but when they sent it back to Cliff it only ran in reverse the way they timed it. They made some new linkages in order to do it so when it was sent to us on the east coast we were asked to time it for foward and the only way to do that was put the johnson bar in reverse and time it for foward. Due to the new linkages we could not time it down for foward. This is supposed to be sent back to China and be fixed. Our suggestion was to tie in the reach rod linkage to the bottom of the reverser as opposed to the top thereby making foward doan and reverse up. They just need to replace the linkages they changed and retime it again.


----------



## JEFF RUNGE (Jan 2, 2008)

Maybe their customers are not worth the effort ?? I don't know, someone should ask the person who makes that call, then you will have the answer. May be it has something to do with the CHINA connection.


----------



## John Allman (Jan 2, 2008)

Due to the new linkages we could not time it down for foward. 

Jason - why is the linkage not symmetrical? It would seem to me that there was more to that issue than that. I need to think about it more, but changing the reverser will not change the value events. You need to change the crank and radius rod angles. Im only guessing, but it seems like it is a left and right handed issue. You can not change one into the other without a geometric change. 

But I differ to those smarter than me. No doubt some of them will speak up.


----------



## jfrank (Jan 2, 2008)

WHEN I RUN OR LOOK AT MY ENGINES I NEVER NOTICE THE DIFFERENCE SO WHO CARES.


----------



## JEFF RUNGE (Jan 2, 2008)

John, Accucraft loves customers like you who don't know any better... But with all the time you spend at Dave Hottman's. I find it hard to believe that part "I NEVER NOTICE" hehehe


----------



## jfrank (Jan 2, 2008)

Posted By JEFF RUNGE on 14 Oct 2009 07:14 PM 
John, Accucraft loves customers like you who don't know any better... But with all the time you spend at Dave Hottman's. I find it hard to believe that part "I NEVER NOTICE" hehehe I know its laughable, but I really don't. I don't even look at it. I look at the server to see if the RC is working. I could care less what the linkage is doing. Steve's is elevated so he scrutinizes every little detail. I didn't even know my BR3 had individual leaf springs nor did I care...but Steve noticed. My railroad is on the ground so when I run something my perspective is from an 'airplane' and I have more things to worry about than leaf springs or the reverse gear....like stuff on the track or making it up the grades or having enough steam, etc. I have to drive and fire my engines, not just sit and watch them go round and round. There's a big difference.


----------



## zubi (May 14, 2009)

Oh, my... the reverser linkage war is looming, Zubi


----------



## JEFF RUNGE (Jan 2, 2008)

John, when I started in the live steam 12 years ago I would not have known, but that is one of the things you learn building kits... Take a look at an Aster mikado, it has D valves modeling an engine with piston valves but no transfer plate, yet the valve gear is down in forward...


----------



## Steve S. (Jan 2, 2008)

*WOW*.....................aren't some of the Accucraft crowd around here touchy







. I started off by saying how impressed I am by the new Accucraft engines. Then I admitted that my complaint could be seen as nit picking. *IMHO*, If they are going to spend the time and effort for all these new improvements and accessories why not get the radius arm position correct ?? But, I guess if you want to run your trains from an airplane it really does not matter.







And, I'm sure that Dave could find a fix for this too if asked.


----------



## Kovacjr (Jan 2, 2008)

From what I am told when it goes back to the factory in a week ot two that they are repairing the issue. The radius rod is planned to be down in foward. For the people that care it will look correct for the people that dont it really doesn't matter. 

Now on to a really good sublect is getting they to offer an axle pump! Every 15 mins you need to refill the boiler and that was not pushing the engine hard. That was pulling 3 cars slow and a low burner setting.


----------



## zubi (May 14, 2009)

Jason, do you still have the engine? I wonder what are the final boiler dimensions. Did they put ball bearings on the (tender) wheels? Best, Zubi


----------



## Charles (Jan 2, 2008)

Posted By JEFF RUNGE on 14 Oct 2009 06:33 PM 
Maybe their customers are not worth the effort ?? I don't know, someone should ask the person who makes that call, then you will have the answer. May be it has something to do with the CHINA connection. Jeff
I did ask the question a while ago. At that time the answer was fashion over function. Interestling how "rivet counters" for fashion can influence the outcome more than "rivet counters" for function (got to be cost factor). Presently the functional ability of the product allows the customer base the level of perform they deem acceptable even when presented with apples to apples comparison. The level of satisfaction goes along with the overall customer philosophy that has driven the "China syndrome" of productivity. Kind of a flash back to the production by sparkies German quality vs China quantity (market demand) and we know that result (yes, many facts involved...). 
The model being spoken about is a visual delight but the functionality could be improved as per the feedback thus far and it seems that Accucraft will follow through (I doubt axle pump and proper valve action) to make the motion seem to be correct.


----------



## rbednarik (Jan 2, 2008)

Posted By JEFF RUNGE on 14 Oct 2009 09:53 PM 
John, when I started in the live steam 12 years ago I would not have known, but that is one of the things you learn building kits... Take a look at an Aster mikado, it has D valves modeling an engine with piston valves but no transfer plate, yet the valve gear is down in forward... 
Jeff,

This is because Aster has made the eccentric trailing on the mikado, essentially throwing the valve events for a 180* loop. They had done this will all of their engines up until the K-4, which is where the cross-port plate began to be incorporated. Yes Steve, even the Bigboys have trailing eccentrics! 

Put your Mike next to your Berkshire (or any other applicable aster engine with cross-porting), rods down on both and you will see the difference. It is a small detail that most do not notice, but it makes them happy that the radius rod is down in forward. It also reduces the cost of the model greatly. However on the high drivered big engines, like the K-4, Berkshire and GS-4, the reversed eccentric looks completely out of place as the throw becomes reverse of what we are accustomed to. If you follow the eccentric swing of the mike and compare it to a non-reversed eccentric locomotive (cross ported or not), such as the Berk, GS-4, S-2, K-4, Allegheny, BR52, BR03, BR62...the list goes on and on.


It is easy to change on the Accucraft models, such as the mason bogie, just a matter of reversing the eccentrics 90* backwards (best to do this with the rods down), much like a ruby, only one is not changing the admission, but rather the sequence in which the valve events occur. Please take note that unless there is a second fulcrum action somewhere in the reversing arm, the reverser will be opposite the norm, being reverse for forward and forward for reverse. The Aster Mikado has this secondary fulcrum located just above the dummy power reverse casting, keeping the correct positioning of the reverser quadrant and the radius rod in the prototypical position. On the screw reverser equipped locomotives, such as the AC-12 and Garratt, this change is not detectable at all.


----------



## Steve S. (Jan 2, 2008)

Hey Ryan, thanks for the info. Thats interesting about the Aster loco's. I guess Aster realized that it is less expensive to use the cross plate for the "correct look" then to do all the other gyrations they had been doing. I think that it is a credit to them that they go to this trouble in the first place. And..............for nit pickers, it sounds like Accucrafts can be corrected if one would want to do so.


----------



## rbednarik (Jan 2, 2008)

Posted By Steve S. on 15 Oct 2009 07:40 AM 
Hey Ryan, thanks for the info. Thats interesting about the Aster loco's. I guess Aster realized that it is less expensive to use the cross plate for the "correct look" then to do all the other gyrations they had been doing. I think that it is a credit to them that they go to this trouble in the first place. And..............for nit pickers, it sounds like Accucrafts can be corrected if one would want to do so. 

Steve,

Not that it was cost effective to cross port by any means. If anything the extra machining and design adds more to the cost, but rather on their earlier models, they had not thought of the cross port design and were simply trying to produce reliable, easy to assemble models. It is less expensive to create a trailing eccentric valve gear then it is to design a cross ported set of cylinders. I have first hand experience in this, as I have been doing it on the AC-12's that are getting TRS upgrades. It is a lot of maths and design work to get everything aligned properly, as well as being able to keep the same passage surface area throughout. 


Yes, I am a functional nit-picker. It makes sense on an engine such as the AC-12 that if one is to open up the existing 1.5mm passages to 2 or even 2.5mm to make the aesthetics of the valve gear correct to prototype as well. It does not take much to cross port the cylinders if one is going to port them. But that is another topic I am sure.


----------



## JoelB (Jan 3, 2008)

I started a thread some time back with the same question about the valve gear on my Accucraft "Earl/Countess". I don't think of myself as a rivet-counter, but it did bother me a wee bit that on a slide-valve engine with nearly every other detail accurately reproduced, the eccentric crank was backwards. I couldn't imagine that it had to do with the position of the reverse lever, that's easy to engineer. And it sounds like making it "right" is merely a question of moving the crank 180 degrees. 

So -- if it's that easy, why wasn't it done correctly in the first place? I think that's the essence of Steve's question.


----------



## Dan Rowe (Mar 8, 2009)

Hi Guys,
I am not a rivet counter I am an engineer I will specify the size and pitch of the rivets for the application after checking my engineering books.

Anyway the only valve gear I know much about is Stephenson valve gear and there are three things that will make it do a 180 flip. 
One is to switch from inside to outside admission or piston valves to D slide valves. The second one is to add or remove the rocker shaft. The third one is to switch the angle of advance on both eccentrics. The last one can be made simple by swapping the ends of the eccentric rods on the radius link.

Most rod engines used a rocker shaft but a some do not and were direct Stephenson.
Most Shays were direct Stephenson and used D slide valves but some used piston valves and some used a rocker shaft.

Most other gears will have the first two answers involved but radial gears only use a single eccentric so the third choice is not an option.

None of you guys are comnplaining about the Aster Shays....anyone want to know what they got wrong on the WM #6 and not the rivet detail?
Dan


----------



## JEFF RUNGE (Jan 2, 2008)

Ryan, I knew what they did when I built the kit in 1999. to put it in KISS terms, they reverser the location of the connecting points on the combination lever. The valve spindle is attached above the radius rod instead of below. They did a good job of hiding this behind the guide.


----------



## Steve S. (Jan 2, 2008)

JoelB said:
So -- if it's that easy, why wasn't it done correctly in the first place? I think that's the essence of Steve's question.

Thank you............................you "_hit the nail on the head "_. I understand this having not been addressed after a few Loco's, but after all these years and many, many Loco's later why has it not been corrected?? I am beginning to see that far more have noticed this then I thought. Maybe this is not nit picking after all. It's actually just expecting them to do what everyone else has been doing all along.


----------



## rbednarik (Jan 2, 2008)

Posted By Steve S. on 15 Oct 2009 01:06 PM 
JoelB said:
So -- if it's that easy, why wasn't it done correctly in the first place? I think that's the essence of Steve's question.

Thank you............................you "_hit the nail on the head "_. I understand this having not been addressed after a few Loco's, but after all these years and many, many Loco's later why has it not been corrected?? I am beginning to see that far more have noticed this then I thought. Maybe this is not nit picking after all. It's actually just expecting them to do what everyone else has been doing all along. 

Simple...cost and time. It has been once said that if the customer wants to have the engine done to his specifications and likes, he should give the manufacturer a blank check. The 2-10-2 F4/5 for example would probably have increased in price nearly 1/3, bringing the total to around 5000-5200 usd, depending on the base price. For most it was deemed good as is, no need to spend more money on a limited production range. And the engine was priced right for what was included on the mechanical front. It runs and looks the part for the majority of their customer base, and that is what counts in the end. 



Again, I know from first hand experience how much work and maths is involved to get it right. Not to mention that the valve gear needs to be non-simple eccentric and actually incorporate a working combination lever. This requires new valves that include steam lap. The list goes on. Some manufactures feel it worthwhile and cost effective to do this in an effort to get and keep the customer base that demands performance and looks, while others feel it cost prohibitive based on their customer base.


----------



## llynrice (Jan 2, 2008)

I have an Accucraft K28 which I love and run regularly and I really and truly do not care whether the radius rod is up or down when it's running forward.

Llyn


----------



## jfrank (Jan 2, 2008)

Dan, Ryan, Charles and Jeff, you guys are amazing with the knowledge you have accumulated. Thank you again for sharing all that with us. Like I have said before, I appreciate the complexity and beauty of an Aster locomotive and love to watch them at Diamondhead and at Steve's. I have a BR3 myself. But the bottom line for me is just running and enjoying them and Accucraft fills that need just fine as they are. All my Accucraft is narrow gauge 1:20 scale and I have a good time playing with them. And that is what it's all about anyway. Having fun. And Jeff, I am sure Dave Hottman could change all that linkage if he wanted too, but what he really does is improve the performance and that is why I took a few of my engines to him. Neither he or I were worried about asthetics. We just wanted engines that would pull stumps out of the ground and we got them.


----------



## Charles (Jan 2, 2008)

John, Llyn, 

We all share a common interest; the hobby of model railroading, in particular to live steam. For Ryan and myself our approach has been influenced by three factors: Aster kits, Accucraft improvements and connections with very knowledgeable/experienced master steamers allowing us to seek answers to questions such as the one posed by Steve, "why is it done that way?" 


For others it is scale modeling, operations, extensive layouts, etc. Some of most interesting steamups have been the gathering of participants where there are discussions of a problem or sharing of a solution. The quest for a better functioning locomotive may not always come about unless others become aware of what is possible.


There are times we can contribute and other moments where we learn from those who have the knowledge and experience...so, Dan what is the incorrect design utilized on the WM Shay? (I think you had mentioned it before in another thread)


----------



## Steve S. (Jan 2, 2008)

I did not intend for this to morph off into a battle here. On an engine like the 2-10-2 are we talking major time, effort and expense to make one look like it's running right ??


----------



## Dave -- Use Coal (Feb 19, 2008)

Wow!!!! This is all to complicated for me. I am just glad the small scale live steam locomotives run at all.


----------



## Charles (Jan 2, 2008)

Here is some good ol' "southern comfort"- small scale engines have been chuffing along in gauge one since 1909!(gauge one was standardized according to resources). Surely amazing when one considers the variety of "done that way" throughout the years.


----------



## zubi (May 14, 2009)

Charles, shouldn't we be celebrating 100 year anniversary?? Best wishes, Zubi


----------



## Dan Rowe (Mar 8, 2009)

Charles, 
As to the Aster WM #6 and Greenbriar #12 the valve gear is visually correct. The 180 flip is in the Johnson bar and as this was my first steam engine I thought that was normal untill some one told me different. 

This is inereristing to me as in light of my last post on this thread I should be able to correct this problem by flipping the eccentrics by 180. Visually this will make a slight difference as the eccentrics will be at the other extream travel for any crank angle but that is in my mind a better way than having the Johnson bar backwards. 

Model engineering is a series of comprmises each designer has a different set of rules for what is close enough. 
Dan


----------



## David Rose (Jan 2, 2008)

Posted By rbednarik on 15 Oct 2009 02:12 PM 
Posted By Steve S. on 15 Oct 2009 01:06 PM 
JoelB said:
So -- if it's that easy, why wasn't it done correctly in the first place? I think that's the essence of Steve's question.

Thank you............................you "_hit the nail on the head "_. I understand this having not been addressed after a few Loco's, but after all these years and many, many Loco's later why has it not been corrected?? I am beginning to see that far more have noticed this then I thought. Maybe this is not nit picking after all. It's actually just expecting them to do what everyone else has been doing all along. 

Simple...cost and time. It has been once said that if the customer wants to have the engine done to his specifications and likes, he should give the manufacturer a blank check. The 2-10-2 F4/5 for example would probably have increased in price nearly 1/3, bringing the total to around 5000-5200 usd, depending on the base price. For most it was deemed good as is, no need to spend more money on a limited production range. And the engine was priced right for what was included on the mechanical front. It runs and looks the part for the majority of their customer base, and that is what counts in the end. 



Again, I know from first hand experience how much work and maths is involved to get it right. Not to mention that the valve gear needs to be non-simple eccentric and actually incorporate a working combination lever. This requires new valves that include steam lap. The list goes on. Some manufactures feel it worthwhile and cost effective to do this in an effort to get and keep the customer base that demands performance and looks, while others feel it cost prohibitive based on their customer base. 


Along the lines of what Ryan said... and I maybe way off, but say that 90% of people don't notice or care. The 10% (_some who it seems don't even purchase Accucraft_) that push (or 'nit pick' per the title) it be implemented would be making the 90% who don't care pay for it. There are other manufactures, that charge more, and implement these types of things if you want them. We have a choice! I would hate to see that Accucraft is being pushed to another level that is too costly for some. Keep the choice there...


----------



## Steve S. (Jan 2, 2008)

David Rose said:
Along the lines of what Ryan said... and I maybe way off, but say that 90% of people don't notice or care. The 10% (_some who it seems don't even purchase Accucraft_) that push (or 'nit pick' per the title) it be implemented would be making the 90% who don't care pay for it. There are other manufactures, that charge more, and implement these types of things if you want them. We have a choice! I would hate to see that Accucraft is being pushed to another level that is too costly for some. Keep the choice there... Thats another good answer to my question. Makes sense to me, thanks for all the responses.


----------



## jfrank (Jan 2, 2008)

Posted By Steve S. on 18 Oct 2009 08:49 PM 
David Rose said:
Along the lines of what Ryan said... and I maybe way off, but say that 90% of people don't notice or care. The 10% (_some who it seems don't even purchase Accucraft_) that push (or 'nit pick' per the title) it be implemented would be making the 90% who don't care pay for it. There are other manufactures, that charge more, and implement these types of things if you want them. We have a choice! I would hate to see that Accucraft is being pushed to another level that is too costly for some. Keep the choice there... Thats another good answer to my question. Makes sense to me, thanks for all the responses.











And Steve is one of that 10% that doesn't even own an Accucraft locomotive and apparently is not going to change that status.


----------



## Steve S. (Jan 2, 2008)

John Frank Said:
And Steve is one of that 10% that doesn't even own an Accucraft locomotive and apparently is not going to change that status.
Thats not fair John, I do own some of their stationary rollers.


----------



## AzRob (Sep 14, 2009)

Shoot, all this talk about doing things one correct way or another is in fact very interesting, but David makes a good point - driving up the costs will drive newcomers out of the market...like me. I can't afford an engine that even has rivet details! I like details, and I like accuracy, but I like being able to own live steam engines too!


----------



## Charles (Jan 2, 2008)

"I would hate to see that Accucraft is being pushed to another level that is too costly for some. Keep the choice there..." as per Dave Rose


On the other hand offering inferior products and/or components at any cost is not going to keep customers, so the nit picking can be a good thing as per F4/F5 which would have had the some poor design on the cross head as the cab forward but....

Not only did Accucraft improve the components but did it on an engine at a lower cost which indicates that both can be done: quality looks and mechanical parts (functionality-that is another story as per this discussion) at a market price that is attractive to hobbyists.


Dan
Confirm...I was not sure if our WM Shay had another aspect of function in queston that we were not aware of, thanks.


----------



## placitassteam (Jan 2, 2008)

I find this thread amusing and confusing. I know nothing about most of the locos dicussed but I do know somthing about modeling the Mason Bogie. Using David Fletcher's great drawings and laser cut valve gear I had no problem getting the parts to be in the proper position when running forward. I did notice in a photo somewhere that Accucraft has the J-Bar pivot above the reach rod rather than below as it should be. That makes everything else operate backward. I have one on order and I'm sure that I will change the valves if they come backward even if it means redoing some of the linkage. The reversed expansion link would not bother me as much as having the lifting levers sticking up in foward as they are quite visible.


----------

