Assuming your MDC shay has been assembled _properly_,
and the lineshafts haven't been messed-with,
(modellers tend to want to file down various components to get the expanding sleeve joints to "work",
only to realise they've taken too-much-material away and they fall-apart under varying conditions!)
down to 15" in both Left and Right-hand turns should be do-able.
(Length of the sleeve-joint shaft + 0.001"-accurate placement of the uni-joints will determine if
- the shafts bottom-out under compression on RH turns,
OR
- drop out of the square sleeves when fully-expanded on LH turns).
Also be aware that if you are using the original MDC centreline ball-shaft driveline and cup system,
and the cup slots have been (un-necessarily) filed open too wide,
(there's "removing flash", and then there's heavy-handed slop-inducing over-filing!),
tight turns may cause the drive-shafts to bind at the truck-end, or pop out from the truck cup.
Some modellers have reported issues keeping the 3rd-truck bunker on the track, esp under hard reversing pulls (which strangely enough was just like the prototype!). In model form, this can often be traced to:
- poor assembly of the 3rd truck
- mis-configured Uni-joint orientation (whip-velocity VS "Constant velocity" configuration)
- additional pickup wiring to the 3rd truck being too stiff, and putting excess forces on the loco<>bunker relationship
I know it says "MDC" on the box, but it is a Shay,
(IE a geared loco, where geared-locos are some of the most complex drive mechs known in both prototype and model forms),
and treating it like a "shake the box" freightcar kit is a recipe for pain and disappointment...
In contrast, the Rivarossi Heisler is a well-engineered and assembled loco,
(haven't come accross a bad one "out of box" yet,
although I have come accross a few which have been AB/used and are a little worse for wear),
and therefore will not tolerate much below 18"
(actual mechanical truck rotation limits prevent operation on tighter curves).
Comments
Maybe
Shays come in a lot of track gauges and sizes, and from a lot of makers. The old HO-scale "Cowichan" Shays from PFM were good down to about 15".
Bachmann 3 truck Shay will make 18"
My Bachmann 3 truck standard gauge Shay will make 18".
Art
Shay
Thanks for reply,I have an old Roundhouse class C three truck shay.Also have aRivarossi two truck Heisler.
Shay
Thank you
MDC Shay on 18"
Dear ???
Assuming your MDC shay has been assembled _properly_,
and the lineshafts haven't been messed-with,
(modellers tend to want to file down various components to get the expanding sleeve joints to "work",
only to realise they've taken too-much-material away and they fall-apart under varying conditions!)
down to 15" in both Left and Right-hand turns should be do-able.
(Length of the sleeve-joint shaft + 0.001"-accurate placement of the uni-joints will determine if
- the shafts bottom-out under compression on RH turns,
OR
- drop out of the square sleeves when fully-expanded on LH turns).
Also be aware that if you are using the original MDC centreline ball-shaft driveline and cup system,
and the cup slots have been (un-necessarily) filed open too wide,
(there's "removing flash", and then there's heavy-handed slop-inducing over-filing!),
tight turns may cause the drive-shafts to bind at the truck-end, or pop out from the truck cup.
Some modellers have reported issues keeping the 3rd-truck bunker on the track, esp under hard reversing pulls (which strangely enough was just like the prototype!). In model form, this can often be traced to:
- poor assembly of the 3rd truck
- mis-configured Uni-joint orientation (whip-velocity VS "Constant velocity" configuration)
- additional pickup wiring to the 3rd truck being too stiff, and putting excess forces on the loco<>bunker relationship
I know it says "MDC" on the box, but it is a Shay,
(IE a geared loco, where geared-locos are some of the most complex drive mechs known in both prototype and model forms),
and treating it like a "shake the box" freightcar kit is a recipe for pain and disappointment...
In contrast, the Rivarossi Heisler is a well-engineered and assembled loco,
(haven't come accross a bad one "out of box" yet,
although I have come accross a few which have been AB/used and are a little worse for wear),
and therefore will not tolerate much below 18"
(actual mechanical truck rotation limits prevent operation on tighter curves).
Happy Modelling,
Aim to Improve,
Prof Klyzlr
Shay
Thanks for all the info,great help.