|
|
Post by diburning on Sept 20, 2012 10:05:56 GMT -8
Yesterday, I bought a custom painted Proto 2000 SD45. I know that the P2K SD45 has a 9:1 gear ratio, making it a fast engine. I know that swapping the 2x worm with a 1x worm will make the gear ratio 18:1, but that would make the engine too slow. Ideally, I'd like a ratio of 12:1 or 14:1. I know that once I install DCC in the thing I can change the speed, but I would lose motor torque that way.
Now, here is my plan. The sideframes on the P2K SD45 are very shallow detail-wise so I was thinking of swapping the drive and trucks with Athearn ones. I don't have an Athearn SD45 to compare, but does anyone know whether the trucks have the same mount?
If that won't work, how hard will it be to adapt the shell to an Athearn or Kato drive?
|
|
|
|
Post by Donnell Wells on Sept 20, 2012 11:59:07 GMT -8
Here's a photo gallery of Liz Allen's Proto SD45 body mounted on an Athearn SD40/45 frame:
www.pbase.com/elizabethallen/sd45_8880
I know that both the prototype SD40 and 45 share the same frame, but I'm not sure about the two Athearn models.
Here's another one of her galleries showcasing an SD40 on an Athearn drive:
www.pbase.com/elizabethallen/sd40_8466
Her method uses a milling machine to remove some of the material from the locomotive frame. I believe this is to make room for the underframe detail. Depending on what you are planning to do regarding detailing, I'm not sure if this step is absolutely necessary.
Donnell
|
|
|
|
Post by stevef45 on Sept 20, 2012 13:23:51 GMT -8
not to hijack this thread, but does anyone know what brand radiator screens were used on Elizabeth Allens proto SD45 shell on athearn frame? They dont look either the DA or Cannon ones.
|
|
|
|
Post by diburning on Sept 20, 2012 15:32:32 GMT -8
I don't need all that underframe detail. I do have a few project SD40s on the back burner right now. I'll try swapping the frames to see whether they'll fit. If not, I'll see if the trucks are a similar mount. I don't have access to a milling machine so that option is out for me.
|
|
|
|
Post by upwpfan on Sept 21, 2012 7:31:58 GMT -8
Folks; To answer the original question. You cannot swap Athearn trucks for PK 2's in a PK 2 frame. The PK2 drive was a problem when it came out because of the basic design. Gear ratios just do not match other designs. If you try to use an Athearn frame then you have major milling to do to get it to fit.  Regards Jere Ingram |
|
|
|
Post by el3637 on Sept 21, 2012 23:09:01 GMT -8
not to hijack this thread, but does anyone know what brand radiator screens were used on Elizabeth Allens proto SD45 shell on athearn frame? They dont look either the DA or Cannon ones. Those are the Proto grills that come with it. Short of going with the 2-layer Plano etched grills they are about the best out there. Cannon has never made SD45 grills, although it's possible to kitbash them from the GP/SD40 grill although it will lack the bend at the top and bottom. Plano's etched grills are made in two versions - diamond mesh and rectangular mesh, both with the rectangular outer wire grills. They are designed to fit the P2K shell but could be adapted to others. A not very good picture of some preproduction Plano grills that I botched the installation of - but it gives you some idea what they look like. Production ones installed correctly look much better but I don't have a finished picture handy.  Andy |
|
|
|
Post by bnsf971 on Sept 22, 2012 1:24:56 GMT -8
My way of fixing the problem was to install 1:1 worm, and changing cv6 upward until the engine ran at the same speed as my other engines up to roughly half throttle. Since about 95+% of my operations are below 50% throttle, it was never an issue.
|
|
|
|
Post by Donnell Wells on Sept 22, 2012 10:51:59 GMT -8
Hey Terry,
Which worms, or who's worms rather, did you use? I have four of the Proto SD45 drives, and will eventually want to do something with them, and would like them to at least be compatible in the lower speed range as other manufacturers' locomotives.
Donnell
|
|
|
|
Post by bnsf971 on Sept 22, 2012 12:51:46 GMT -8
Hey Terry,
Which worms, or who's worms rather, did you use? I have four of the Proto SD45 drives, and will eventually want to do something with them, and would like them to at least be compatible in the lower speed range as other manfaturers locomotives.
Donnell I used some worms that were in my junk box. They started out life in Athearn F units, and were pretty easy to swap out. The ones I used were for want of a better description, "coarser" looking, with a different number of teeth than the OEM Proto worms. |
|
|
|
Post by spookyac47 on Sept 22, 2012 15:42:59 GMT -8
Hey Terry,
Which worms, or who's worms rather, did you use? I have four of the Proto SD45 drives, and will eventually want to do something with them, and would like them to at least be compatible in the lower speed range as other manfaturers locomotives.
Donnell I used some worms that were in my junk box. They started out life in Athearn F units, and were pretty easy to swap out. The ones I used were for want of a better description, "coarser" looking, with a different number of teeth than the OEM Proto worms. Athearn "F" units? Which generation, early blue box, current producton or Genesis? |
|
|
|
Post by bnsf971 on Sept 22, 2012 18:29:24 GMT -8
I used some worms that were in my junk box. They started out life in Athearn F units, and were pretty easy to swap out. The ones I used were for want of a better description, "coarser" looking, with a different number of teeth than the OEM Proto worms. Athearn "F" units? Which generation, early blue box, current producton or Genesis? They were "plastic", so I think they were later model RTR. |
|
|
|
Post by Donnell Wells on Sept 22, 2012 18:35:21 GMT -8
Hi Terry, is this fix possible for the SD60 chassis as well?
Donnell
|
|
|
|
Post by bnsf971 on Sept 23, 2012 5:21:54 GMT -8
I don't know. I traded the SD45 I performed this modification on for something that better fit my era and road, so I can't swap worms to see if they would work. I don't have an SD60 to compare, either. I would say "maybe",but Proto seems to use the "drive of the month" club for supplying them.
|
|
|
|
Post by diburning on Sept 24, 2012 22:58:25 GMT -8
Yes and no.
The SD45 has a 9:1 gear ratio because it has a 2x worm. The SD50/60s have an 18:1 gear ratio.
Swapping the worms will make a 9:1 an 18:1, and make the 18:1 to 9:1. There's no way to fix it to 14:1 or 12:1. It's either too fast or too slow, which is too bad.
|
|
