# Accucraft Shay Advice - Slip Joint



## 8104 (Jan 17, 2010)

Hello All,

Recently, I purchased an Accucraft Shay and I was wondering if anyone had any advice on improving the performance of the slip joints. While breaking it in, I noticed that the rear slip joint tends to slide out on some of my corners. Since the tightest corner is 8 foot (diameter) and it does not occur on every corner or every time around, I have a feeling the joint is probably just barely hanging on in the corners.


Does anyone have any suggestions? Thank you.


Graeme


----------



## David Leech (Dec 9, 2008)

Hi Graeme, 
Turn the Shay around!!!! 
Or do you have 'left' and 'right' corners? 
All the best, 
David Leech, Delta, Canada


----------



## 8104 (Jan 17, 2010)

Hello David, 

Unfortunately, the layout is a modified dog bone style layout so there are left and right corners throughout. 

Thank you for the suggestion. I wish it had been that simple. 

Graeme


----------



## tacfoley (Jan 3, 2008)

Sir - you are right on the very limit of the manufacturer's recommended minima of 48in radius curves for both the two and three-cylinder Shays. There is a fix, but unless you are a home builder you won't like it. It involves obtaining - or making - longer square drive shafts. There is still a danger of transmission lock, however. There is little or no flexibility in these old-fashioned drive trains. 

Let us know if you are really stuck - it wouldn't take long to knock out a couple that are slightly longer. 

tac 
www.ovgrs.org 
Supporter of the Cape Meares Lighthouse Restoration Fund


----------



## bertiejo (Aug 11, 2008)

Hi Graeme: I have almost the same situation as you. I have a 2-cyl Accucraft Shay and a double dogbone layout. I initially built it with 5' diameter curves (before I bought the Shay) and I found that it would actually run OK one way on the 5' curves until it got to the straight track transition where the curve was reversed. I even got it to occasionally negotiate this stretch if I slowed it down greatly but it was obvious to me that it was stressing the slip joints and I am in the process of re-building the curves to 8' diam. My guess is that as the engine breaks in 8' should work OK. For whats its worth my two 3 axle engines (Frank S and War Dept Baldwin) run just fine on the 5' diam curves. bertiejo


----------



## 8104 (Jan 17, 2010)

Thanks All, 

It looks like I will need to look into obtaining or making longer square drive shafts. In the meantime, I will try breaking in the engine and see if it improves the performance around the corners. Thank you for all your suggestions. 

Graeme


----------



## HMeinhold (Jan 2, 2008)

If one of the joints slips out much sooner than the other one, the inner squares might be switched between front and back. 
Regards


----------



## jfrank (Jan 2, 2008)

Use a wider radius turn. 8' diameter(4' radius) is just to sharp.


----------



## tacfoley (Jan 3, 2008)

Posted By jfrank on 20 Mar 2011 07:47 PM 
Use a wider radius turn. 8' diameter(4' radius) is just to sharp. 
John have a heart. For some folks, 'using a wider turn' is not an option, particularly if they have a permanent layout built into the ground. F'rinsance, my tiny square backyard is filled to capacity with my circular 'up-on-sticks' trackage, leaving space for my reloading shed in one corner.

My subtle hints to extend off the track route and straight into the house to ease the job of loading thirty and forty pound locos has been met, so far, with frosty silence by mrs tac...

tac
www.ovgrs.org


----------



## Wesley Furman (Jan 2, 2008)

Graeme 
Let me go way out on a limb here. 
Maybe the opponent truck is stiff and not carrying it share of the bending in a curve. Try loosening up the truck, oil, lube, etc. and see what happens. 
At Diamondhead I discovered some Shays that had a very small brass tubes soldered on the back of the pilots to keep the trucks from over rotating. This helped keep the slip joint from coming out when moving the Shay by hand. They (and now mine) had no problems making a tight bend. The “Stopper rod” would also help with both trucks sharing the rotation when on the track and keep the slip joint from separating. 
Or on the other hand maybe it is too early in the morning for me to be thinking. Good luck on all of the responders suggestions. 
Wesley 
SA #212


----------



## 8104 (Jan 17, 2010)

Sorry about the delay in responding, I have been traveling. As for using a wider corners, I would love to have 10+ foot corners but my neighbors and their dogs would likely have a problem with holes in the fence. As for all of the other suggestions, I will definitely try lubricating and modifying the engine to this correct this issue. I will also be visiting a friend's layout (with wider corners) in a couple of weeks time so I will attempt to maximum the run time and break the engine in. 

Thank you for the suggestions. 

Graeme


----------



## Dan Rowe (Mar 8, 2009)

Graeme , 
There needs to be two checks made to solve the problem of a Shay on a tight curve. As sugested a longer square shaft might solve the problem how ever the other problem is the square shaft will bottom out in the coupling sleeve or hollow square shaft on an isnide curve. 

I would place the loco on the minium radius both ways to check the square shaft at min. and max. extension to see if the advice of increasing the square shaft length will work on your line. You might have to make a longer coupling sleeve to solve your problem. 

There were different length of both the square shaft and the coupling sleeve for several Shay plans to solve this problem in full scale. 

Dan


----------



## Kovacjr (Jan 2, 2008)

Is this a new production Shay or one of the orignal ones? They had changed the drivetrain in the newer ones. Different slip joinjts and different gears. I have a older one along with a few friends and it will run on 8' Dia. It wont run on anything smaller as the shaft bottoms out. Check to see how much of the square shaft is in the joint on the 8' curve like Dan mentioned. Also measure both. One is shorter than the other on mine. I actually had to shorten it more as it would not orignally run on a 8' dia. With that being said there is little left in the joint going the other way.


----------

