Topics

RPO project - BM70Ka


Chuck Heuer
 

Starting a new thread to track my project, and following up to my post #10467 as quoted below; once I actually started drilling the doors I quickly realized a couple things:

- first, the drill starting points on the doors are not intended for door mounted grabs but rather to align with the body mounted grab points so the can pass through and help with getting a flush fit of the doors. I intend to use plastic shim stock, as suggested as an alternate in the instructions, to give the doors prototypical recess; so that material will also have to be drilled through after attachment.
- second, in my kit I actually received 4 identical baggage doors. Since all 4 open in the same direction on the car, 2 actually needed to be drilled on the opposite side from where they have started holes. Since the doors are L/R symmetrical I was able to easily clamp a pair face to face and use an already drilled door as a template for the 2 which needed reverse side holes for stationary grab clearance.
- Now, however, I will have to layout the actual door mounted grabs and starting points on at least one baggage door myself. So far I have not found a really satisfactory way to get adequate drill starting points on this relatively thin stock without creating indentation. The starting points provided on both sides and doors in the kit seem to have been drilled rather than punched. Unfortunately I do have a small, precision drill press or milling machine that would let me duplicate this technique (and execute the drilling for that matter). My thought at the moment is to need to make a plastic template for this; I would, however, be happy for any suggestions from the experience of the group.

I am also considering adhesives for this project and would be interested in experiences and observations from those with experience in assembly such a mixed materials build (brass and styrene in this case). I am considering springing for a starter order of Cypox, following discussions both recently and historically over on the Passenger Car list. Canopy glue and of course ACC are also candidates I am aware of (and more familiar with), as well as the various plastic cements for the plastic to plastic interfaces.

Chuck Heuer


Feb 13   

"the NKP BM-70Ka kit I'm getting started on came with a spliced clerestory roof described as made from BCW roofs (one seam, at the center). It is also supplied with BCW PRR baggage car ends and a BCW floor.Moving slowly and carefully as this is the first brass side car kit I have tackled. Getting sides and ends to being paint ready is the first major phase. Making careful study and consideration on size and placement of all the grabs before drilling began, I have completed drilling the sides. I found NKP had provided starting points for grabs on the 2 mail doors, I will not drill (or install) these as I don't find them in photos; and grabs on these doors is not compatible with a pocket door able to retract completely out of the body opening - as frequently seen in open mail door photos. The baggage doors are center punched for grabs on one side, prototypically, but they are set as the same length as the adjacent fixed grab on the body which is at an best an uncommon length. I will use the upper marked location on these doors but make them about 25 - 30% shorter. Then  I will tackle the ends and their grabs."


Bruce Smith
 

Chuck,

I'm not a Cypox fan. As best I can tell, it is basically overpriced Cyanoacryalte. Now don't everyone come down on me. I KNOW that they say it isn't, but the data that they provide indicates that, while perhaps a slightly altered formulation, it isn't actually all that different. The plastic prep that comes with it works great, but also works with regular CA. I have actually used it, and never reordered because, at least in my hands, the hobby shop CA, or for that matter, Wally Mart Locktite CA work just as well.

YMMV,
Bruce
Bruce Smith
Auburn, AL


From: PRRPro@groups.io <PRRPro@groups.io> on behalf of Chuck Heuer <hiker120@...>
Sent: Tuesday, February 16, 2021 11:34 AM
To: PRRPro@groups.io <PRRPro@groups.io>
Subject: [PRRPro] RPO project - BM70Ka
 
Starting a new thread to track my project, and following up to my post #10467 as quoted below; once I actually started drilling the doors I quickly realized a couple things:

- first, the drill starting points on the doors are not intended for door mounted grabs but rather to align with the body mounted grab points so the can pass through and help with getting a flush fit of the doors. I intend to use plastic shim stock, as suggested as an alternate in the instructions, to give the doors prototypical recess; so that material will also have to be drilled through after attachment.
- second, in my kit I actually received 4 identical baggage doors. Since all 4 open in the same direction on the car, 2 actually needed to be drilled on the opposite side from where they have started holes. Since the doors are L/R symmetrical I was able to easily clamp a pair face to face and use an already drilled door as a template for the 2 which needed reverse side holes for stationary grab clearance.
- Now, however, I will have to layout the actual door mounted grabs and starting points on at least one baggage door myself. So far I have not found a really satisfactory way to get adequate drill starting points on this relatively thin stock without creating indentation. The starting points provided on both sides and doors in the kit seem to have been drilled rather than punched. Unfortunately I do have a small, precision drill press or milling machine that would let me duplicate this technique (and execute the drilling for that matter). My thought at the moment is to need to make a plastic template for this; I would, however, be happy for any suggestions from the experience of the group.

I am also considering adhesives for this project and would be interested in experiences and observations from those with experience in assembly such a mixed materials build (brass and styrene in this case). I am considering springing for a starter order of Cypox, following discussions both recently and historically over on the Passenger Car list. Canopy glue and of course ACC are also candidates I am aware of (and more familiar with), as well as the various plastic cements for the plastic to plastic interfaces.

Chuck Heuer


Chuck Heuer
 

Thanks Bruce. Your experience and comments confirm my instincts and previously gathered information about Cypox. Do you continue to use their plastic prep with common varietals of CA, or have you found other more common products for that purpose adequate? Also, a related question: did you evaluate Cypox as a shapeable putty replacement / filler - another use for which it has been touted?

I have decided to fabricate an acrylic template / jig for drilling the baggage door grabs. A bit of a necessary detour I think. 

Chuck


Bruce Smith
 

Chuck,

My supply of Cypox plastic prep has held out so far, so I haven't explored alternatives. I have also not used it for putty. 

Jigs are a great tool!

Regards,
Bruce Smith
Auburn, AL


From: PRRPro@groups.io <PRRPro@groups.io> on behalf of Chuck Heuer <hiker120@...>
Sent: Tuesday, February 16, 2021 8:15 PM
To: PRRPro@groups.io <PRRPro@groups.io>
Subject: Re: [PRRPro] RPO project - BM70Ka
 
Thanks Bruce. Your experience and comments confirm my instincts and previously gathered information about Cypox. Do you continue to use their plastic prep with common varietals of CA, or have you found other more common products for that purpose adequate? Also, a related question: did you evaluate Cypox as a shapeable putty replacement / filler - another use for which it has been touted?

I have decided to fabricate an acrylic template / jig for drilling the baggage door grabs. A bit of a necessary detour I think. 

Chuck


Rich C
 

My CyPox occupies a spot in my refrigerator. I agree with Bruce, to me it being an overpriced alternative to CA.

Rich Christie

On Tuesday, February 16, 2021, 09:31:02 PM CST, Bruce Smith <smithbf@...> wrote:


Chuck,

My supply of Cypox plastic prep has held out so far, so I haven't explored alternatives. I have also not used it for putty. 

Jigs are a great tool!

Regards,
Bruce Smith
Auburn, AL


From: PRRPro@groups.io <PRRPro@groups.io> on behalf of Chuck Heuer <hiker120@...>
Sent: Tuesday, February 16, 2021 8:15 PM
To: PRRPro@groups.io <PRRPro@groups.io>
Subject: Re: [PRRPro] RPO project - BM70Ka
 
Thanks Bruce. Your experience and comments confirm my instincts and previously gathered information about Cypox. Do you continue to use their plastic prep with common varietals of CA, or have you found other more common products for that purpose adequate? Also, a related question: did you evaluate Cypox as a shapeable putty replacement / filler - another use for which it has been touted?

I have decided to fabricate an acrylic template / jig for drilling the baggage door grabs. A bit of a necessary detour I think. 

Chuck