Post by CP_8530 on May 9, 2012 16:09:07 GMT -5
This "build" came about for a variety of different reasons.
1 - Spare parts lying around
2 - Experimenting with modifying stock handrails and bending metal into the proper end profiles
3 - Doing a rebuild CP GP7u
The basis for this model was a used Burlington Northern Proto 2000 GP18 I picked up to salvage the dynamic brake hood section and a few other parts for another project (that I'll try and post sometime later). Once the long hood was cut up for salvage, I still had the rest of a GP18. CP didn't have any GP18's, but they had a few late phase GP9's - which I would have done, but as you can recall the long hood was now in 3 pieces and no DB section.
But, I had a spare GP7 non-DB hood sitting around from a B&O GP7 that donated its chassis to a Kaslo GP9RM. I ended up splicing that onto the GP18, and deciding to backdate it to a GP7. In particular, one of the ex-TH&B rebuilds (CP 1684, as rebuilt without its later RC equipment) as they were built without dynamic brakes. In addition, I'd have to chop the nose and rebuild the cab front face. A number of other challenges popped up along the way though, which made it "fun".
Prototype: www.mountainrailway.com/Roster%20Archive/CP%201600/CP%201684.htm
Step one is to strip the entire shell down, remove all the details, and soak it in rubbing alcohol (99% works nice). The ol' toothbrush scrubbing got rid of most of the paint, but a toothpick was needed in a few areas (grilles, tight corners, etc).
Hood
In this case, the ex-TH&B GP7 units had a lot of lift rings, so I didn't have to fill any lift ring holes but had to drill more out in the non-DB section. The lift rings were all made from bent wire. Fill the unnecessary torpedo tube mount holes (if present). I had salvaged the P2K fans for a Kaslo build, so bought some Details West 36" EMD fans and glued them over the holes. While not see-through, they do look pretty good. The horn was mounted behind the #2 radiator fan, so a hole was drilled for it there.
I had to extend the first door after the conductors' side cab down, as-built the early TH&B units didn't have that step box behind the conductors side, which was really rare for as-built units (some RR's removed them when rebuilt). Instead the hood section was identical to the engineers' side. I drilled out the old section, filed it down, and spliced in the bottom of a hood door from the GP18 hood. Later, I had to move the knuckle busters to the other door after I realized they were on the wrong side...
CP also installed some access doors at the bottom rear of the long hood. Those were drilled out and the openings enlarged for more custom built doors:
Cab
Cab windows were salvaged from an Athearn GP-cab and glued in place. I had already salvaged the numberboards, so fabricated new numberboards using the numberboard housings from the scrapped GP18 long hood end and sheet styrene. The numberboards were cut off the old P2K light bar and cut to fit. Class light housings from a Kaslo GP9RM were glued on above. Bell brackets were scratchbuilt from .10 styrene according to photos. Cab louvres on the ends were shaved off as per prototype photos. Small pieces of styrene subbed for flag holders. Working cab doors were glued in place and re-enforced with styrene from the inside. The oversize sunshades and track was removed from the cab, filled with styrene and Squardron putty and sanded smooth. The TH&B GP7's never had any drip strip, so no need to worry about that.
Frame / Fuel tanks
The frame requires some modifications to backdate it. The old GP18 louvres were shaved off, and the larger GP7 style were installed in the battery boxes by drilling and filine them out, and using old louvres off the scrapped GP18 long hood. Some glue and Squadron ensures a good fit. Over time, louvre arrangements varied from unit to unit, always refer to prototype photos.
Thankfully, CP GP7/9's had their skirts removed, so using a GP18 frame isn't a problem. Slice the mild GP18 skirting up to the frame, being careful to cut out the fuel filler/sight glass/emergency stop housing. Cut all the steps out and replace with appropriate Canadian style steps (in progress on my model). Patch the 2 holes in the end pilots at both ends, as GP7's didn't have those. Patch all the end railing holes near the steps, and drill new ones according to prototype photos (the rebuilt ones mounted slightly different).
I patched the hole in the frame where the fuel filler was, and mounted it further back. I cut a piece of styrene to profile and fit it around the filler as per prototype. The sight glass is mounted on the top of the fuel tank, and the emergency shutoff button on its own piece of styrene near the front.
The box behind the conductor's side of the walkway was cut off, and the small end piece was saved and mounted by the cab, a la the engineer's side. There was no step on this side when rebuilt. Fill the holes in the frame walkway and rear of cab with styrene bits.
Fuel tanks...I also salvaged the P2K fuel/air tanks for another project, but will probably make due with the P2K part from another unit. Even though it's the larger incorrect 1600gal tank, I could live with it until I find some correct ones.
Now would be a good time to add the footboards/pilot block (also salvaged for another project(!), so this part is still pending on mine).
Nose
The nose was chopped. I went by photos in determining the height, and scored it with an x-acto knife before cutting through. First around the bottom of the nose sides along the strip near the walkway, then further up (taking a section out the middle and lowering the top, as CP did). Glue together and patch the front of the nose sections with Squadron putty. The great thing about P2K shells (at least the geeps) is they're not as hard or thick as Atlas or Athearns, so chopping is much easier.
The two small class lights at the nose corners were carefully sliced off. I patched the numberboards and any grab and lift ring holes with sheet styrene and Squadron putty, as well filing off all the details on the roof and left side of the nose (door area). I cut two notches in the bottom of the nose and fabricated a few access doors from spare knuckle busters and hinges from the scrap GP18 long hood. Holes were drilled for grabs according to prototype photos (meant for reusing the stock ones). Since it was a GP18, it had the later style headlights, where it should have the earlier style (more round). I used a leftover light that was carved off another project, and carefully carved off the GP18 ones from the hood for reuse (for a pending Athearn CP Trainmaster project).
*Note, the sand hatches were later scratchbuild to replicate the large square-ish CP rebuilt type, from styrene bits. No pictures show this however (coming later!).
Handrails
The handrails were swapped for a pair of earlier ones with bolted stanchions from the B&O GP7, and were modified to be the rebuilt Canadian style. I experimented with drilling out the handrails but found it too tedious to do them all, so I cut off the ends and drilled them to fit .015" piano wire, bent to the correct profile. They were bent according to prototype photos and installed.
I also had to modify the ones on the conductor's side of the long hood in a similar fashion, since the box behind the cab was removed.
Chassis / weight / couplers
The GP18 weight required some cutting to adapt to the low-nose GP7, as well as give more space for a future DCC installation. I started by cutting a small notch out of the tip of the nose with a hacksaw, so a light would fit in the space. Then I cut a section off the rear, as the P2K GP7 light bar on the long hood end was slightly larger than the GP18. The grand finale was cutting a large open section on the front with Mr. hacksaw again. Clean all areas up with a file and make sure no metal shavings stuck to the weight (there are many).
I cut off the old frame-mount Athearn-style coupler mounts and used a few pieces of thick styrene in their place to mount some Kadee coupler boxes. They were screwed to the frame where the two end weight screws are. I'm still out to lunch on the ultimate shell + chassis mounting system.
This project is still ongoing, and a lot of parts have been left off until the final paint job has been done. Next step, painting.
1 - Spare parts lying around
2 - Experimenting with modifying stock handrails and bending metal into the proper end profiles
3 - Doing a rebuild CP GP7u
The basis for this model was a used Burlington Northern Proto 2000 GP18 I picked up to salvage the dynamic brake hood section and a few other parts for another project (that I'll try and post sometime later). Once the long hood was cut up for salvage, I still had the rest of a GP18. CP didn't have any GP18's, but they had a few late phase GP9's - which I would have done, but as you can recall the long hood was now in 3 pieces and no DB section.
But, I had a spare GP7 non-DB hood sitting around from a B&O GP7 that donated its chassis to a Kaslo GP9RM. I ended up splicing that onto the GP18, and deciding to backdate it to a GP7. In particular, one of the ex-TH&B rebuilds (CP 1684, as rebuilt without its later RC equipment) as they were built without dynamic brakes. In addition, I'd have to chop the nose and rebuild the cab front face. A number of other challenges popped up along the way though, which made it "fun".
Prototype: www.mountainrailway.com/Roster%20Archive/CP%201600/CP%201684.htm
Step one is to strip the entire shell down, remove all the details, and soak it in rubbing alcohol (99% works nice). The ol' toothbrush scrubbing got rid of most of the paint, but a toothpick was needed in a few areas (grilles, tight corners, etc).
Hood
In this case, the ex-TH&B GP7 units had a lot of lift rings, so I didn't have to fill any lift ring holes but had to drill more out in the non-DB section. The lift rings were all made from bent wire. Fill the unnecessary torpedo tube mount holes (if present). I had salvaged the P2K fans for a Kaslo build, so bought some Details West 36" EMD fans and glued them over the holes. While not see-through, they do look pretty good. The horn was mounted behind the #2 radiator fan, so a hole was drilled for it there.
I had to extend the first door after the conductors' side cab down, as-built the early TH&B units didn't have that step box behind the conductors side, which was really rare for as-built units (some RR's removed them when rebuilt). Instead the hood section was identical to the engineers' side. I drilled out the old section, filed it down, and spliced in the bottom of a hood door from the GP18 hood. Later, I had to move the knuckle busters to the other door after I realized they were on the wrong side...
CP also installed some access doors at the bottom rear of the long hood. Those were drilled out and the openings enlarged for more custom built doors:
Cab
Cab windows were salvaged from an Athearn GP-cab and glued in place. I had already salvaged the numberboards, so fabricated new numberboards using the numberboard housings from the scrapped GP18 long hood end and sheet styrene. The numberboards were cut off the old P2K light bar and cut to fit. Class light housings from a Kaslo GP9RM were glued on above. Bell brackets were scratchbuilt from .10 styrene according to photos. Cab louvres on the ends were shaved off as per prototype photos. Small pieces of styrene subbed for flag holders. Working cab doors were glued in place and re-enforced with styrene from the inside. The oversize sunshades and track was removed from the cab, filled with styrene and Squardron putty and sanded smooth. The TH&B GP7's never had any drip strip, so no need to worry about that.
Frame / Fuel tanks
The frame requires some modifications to backdate it. The old GP18 louvres were shaved off, and the larger GP7 style were installed in the battery boxes by drilling and filine them out, and using old louvres off the scrapped GP18 long hood. Some glue and Squadron ensures a good fit. Over time, louvre arrangements varied from unit to unit, always refer to prototype photos.
Thankfully, CP GP7/9's had their skirts removed, so using a GP18 frame isn't a problem. Slice the mild GP18 skirting up to the frame, being careful to cut out the fuel filler/sight glass/emergency stop housing. Cut all the steps out and replace with appropriate Canadian style steps (in progress on my model). Patch the 2 holes in the end pilots at both ends, as GP7's didn't have those. Patch all the end railing holes near the steps, and drill new ones according to prototype photos (the rebuilt ones mounted slightly different).
I patched the hole in the frame where the fuel filler was, and mounted it further back. I cut a piece of styrene to profile and fit it around the filler as per prototype. The sight glass is mounted on the top of the fuel tank, and the emergency shutoff button on its own piece of styrene near the front.
The box behind the conductor's side of the walkway was cut off, and the small end piece was saved and mounted by the cab, a la the engineer's side. There was no step on this side when rebuilt. Fill the holes in the frame walkway and rear of cab with styrene bits.
Fuel tanks...I also salvaged the P2K fuel/air tanks for another project, but will probably make due with the P2K part from another unit. Even though it's the larger incorrect 1600gal tank, I could live with it until I find some correct ones.
Now would be a good time to add the footboards/pilot block (also salvaged for another project(!), so this part is still pending on mine).
Nose
The nose was chopped. I went by photos in determining the height, and scored it with an x-acto knife before cutting through. First around the bottom of the nose sides along the strip near the walkway, then further up (taking a section out the middle and lowering the top, as CP did). Glue together and patch the front of the nose sections with Squadron putty. The great thing about P2K shells (at least the geeps) is they're not as hard or thick as Atlas or Athearns, so chopping is much easier.
The two small class lights at the nose corners were carefully sliced off. I patched the numberboards and any grab and lift ring holes with sheet styrene and Squadron putty, as well filing off all the details on the roof and left side of the nose (door area). I cut two notches in the bottom of the nose and fabricated a few access doors from spare knuckle busters and hinges from the scrap GP18 long hood. Holes were drilled for grabs according to prototype photos (meant for reusing the stock ones). Since it was a GP18, it had the later style headlights, where it should have the earlier style (more round). I used a leftover light that was carved off another project, and carefully carved off the GP18 ones from the hood for reuse (for a pending Athearn CP Trainmaster project).
*Note, the sand hatches were later scratchbuild to replicate the large square-ish CP rebuilt type, from styrene bits. No pictures show this however (coming later!).
Handrails
The handrails were swapped for a pair of earlier ones with bolted stanchions from the B&O GP7, and were modified to be the rebuilt Canadian style. I experimented with drilling out the handrails but found it too tedious to do them all, so I cut off the ends and drilled them to fit .015" piano wire, bent to the correct profile. They were bent according to prototype photos and installed.
I also had to modify the ones on the conductor's side of the long hood in a similar fashion, since the box behind the cab was removed.
Chassis / weight / couplers
The GP18 weight required some cutting to adapt to the low-nose GP7, as well as give more space for a future DCC installation. I started by cutting a small notch out of the tip of the nose with a hacksaw, so a light would fit in the space. Then I cut a section off the rear, as the P2K GP7 light bar on the long hood end was slightly larger than the GP18. The grand finale was cutting a large open section on the front with Mr. hacksaw again. Clean all areas up with a file and make sure no metal shavings stuck to the weight (there are many).
I cut off the old frame-mount Athearn-style coupler mounts and used a few pieces of thick styrene in their place to mount some Kadee coupler boxes. They were screwed to the frame where the two end weight screws are. I'm still out to lunch on the ultimate shell + chassis mounting system.
This project is still ongoing, and a lot of parts have been left off until the final paint job has been done. Next step, painting.
