Topics

Kadee Bracket Grab Iron Hole Locations


Dennis Storzek
 

As Promised, I have surveyed the mounting holes on a Kadee PS-1 body and have uploaded dimensioned sketches to the FILES section at:

http://groups.yahoo.com/group/STMFC/files/Kadee_PS-1_Grab_Iron_Holes/

All dimensions are decimal inches, to four places where necessary. The ordinate dimensions are relative to the center of the grab iron; it is up to whoever develops a drilling jig to properly relate them to other features on the car body.

The first sheet also shows the typical condition at the mounting pin / hole interface. Whoever devised the old joke about putting a square peg in a round hole obviously didn't design plastic parts, because that is exactly what Kadee has done. The mounting pegs are .017" squares with a long tapered lead; they are designed to be pressed into .020" diameter holes. A look at the drawing shows that this combination yields appx. .002" of interference at the corners of the peg, while the unfilled portions of the hole provide a place for the displaced material.This is good design practice, but it does point out that the grabs must be properly oriented before they are pressed in place; ones the corners dig into the circumference of the hole, it will be either difficult or impossible to twist them straight. If this is a problem, the holes can be increased to .024" diameter, and CA used to fill the gaps and lock the mounting peg in place.

Those who were hoping to use the really fine Kadee boxcar ladders on other projects are going to be disappointed, unless they have a drill that drills rectangular holes. Kadee has chosen, wisely, as far as I'm concerned, to make the mounting pegs rectangular, .024" x .044". This allows a much stronger mounting than round pegs could provide, and ensures that the ladders remain straight, but the difficulty of generating the rectangular slots in a model that wasn't molded with them in place is going to preclude using these ladders on other projects. Because of this, I haven't bothered to post the slot dimensions.

These are indeed wonderful parts. The grab irons and ladder rungs measure just .010" in diameter, smaller than the .012" wire that is commonly used in HO scale for these parts. The minimum diameter for these parts on the prototype is 5/8", which scales to .007", but some prototype parts are made from larger stock. The Kadee rung scale to just a bit larger than 7/8", not far from the mark.

Dennis Storzek


Paul Lyons
 

Dennis,
Thanks for all the effort! I hope you have the dimension between the mounting pin holes on the side grabs and just forgot to put it on the drawing? Or perhaps, it is the same dimension as the end grab?
Paul Lyons

-----Original Message-----
From: soolinehistory <destorzek@mchsi.com>
To: STMFC <STMFC@yahoogroups.com>
Sent: Sat, Oct 22, 2011 8:49 am
Subject: [STMFC] Kadee Bracket Grab Iron Hole Locations




As Promised, I have surveyed the mounting holes on a Kadee PS-1 body and have uploaded dimensioned sketches to the FILES section at:

http://groups.yahoo.com/group/STMFC/files/Kadee_PS-1_Grab_Iron_Holes/

All dimensions are decimal inches, to four places where necessary. The ordinate dimensions are relative to the center of the grab iron; it is up to whoever develops a drilling jig to properly relate them to other features on the car body.

The first sheet also shows the typical condition at the mounting pin / hole interface. Whoever devised the old joke about putting a square peg in a round hole obviously didn't design plastic parts, because that is exactly what Kadee has done. The mounting pegs are .017" squares with a long tapered lead; they are designed to be pressed into .020" diameter holes. A look at the drawing shows that this combination yields appx. .002" of interference at the corners of the peg, while the unfilled portions of the hole provide a place for the displaced material.This is good design practice, but it does point out that the grabs must be properly oriented before they are pressed in place; ones the corners dig into the circumference of the hole, it will be either difficult or impossible to twist them straight. If this is a problem, the holes can be increased to .024" diameter, and CA used to fill the gaps and lock the mounting peg in place.

Those who were hoping to use the really fine Kadee boxcar ladders on other projects are going to be disappointed, unless they have a drill that drills rectangular holes. Kadee has chosen, wisely, as far as I'm concerned, to make the mounting pegs rectangular, .024" x .044". This allows a much stronger mounting than round pegs could provide, and ensures that the ladders remain straight, but the difficulty of generating the rectangular slots in a model that wasn't molded with them in place is going to preclude using these ladders on other projects. Because of this, I haven't bothered to post the slot dimensions.

These are indeed wonderful parts. The grab irons and ladder rungs measure just .010" in diameter, smaller than the .012" wire that is commonly used in HO scale for these parts. The minimum diameter for these parts on the prototype is 5/8", which scales to .007", but some prototype parts are made from larger stock. The Kadee rung scale to just a bit larger than 7/8", not far from the mark.

Dennis Storzek







[Non-text portions of this message have been removed]


Schuyler Larrabee
 

I'm glad you posted Paul, as I have yet to receive Dennis' post on this
(Thank you Yahoo . . .)



I have what might be an ignorant question: Is the vertical dimension
between the two grabs at the left end of the car side uniform from car to
car? And is the dimension from the bottom of the car side a uniform
dimension from one car to another?





SGL



From: Paul Lyons
Sent: Saturday, October 22, 2011 1:54 PM

Dennis,
Thanks for all the effort! I hope you have the dimension between the
mounting pin holes on the side grabs and just forgot to put it on the
drawing? Or perhaps, it is the same dimension as the end grab?
Paul Lyons

-----Original Message-----
From: soolinehistory <destorzek@mchsi.com <mailto:destorzek%40mchsi.com> >
To: STMFC <STMFC@yahoogroups.com <mailto:STMFC%40yahoogroups.com> >
Sent: Sat, Oct 22, 2011 8:49 am
Subject: [STMFC] Kadee Bracket Grab Iron Hole Locations

As Promised, I have surveyed the mounting holes on a Kadee PS-1 body and
have uploaded dimensioned sketches to the FILES section at:

http://groups.yahoo.com/group/STMFC/files/Kadee_PS-1_Grab_Iron_Holes/

All dimensions are decimal inches, to four places where necessary. The
ordinate dimensions are relative to the center of the grab iron; it is up to
whoever develops a drilling jig to properly relate them to other features on
the car body.

The first sheet also shows the typical condition at the mounting pin / hole
interface. Whoever devised the old joke about putting a square peg in a
round hole obviously didn't design plastic parts, because that is exactly
what Kadee has done. The mounting pegs are .017" squares with a long tapered
lead; they are designed to be pressed into .020" diameter holes. A look at
the drawing shows that this combination yields appx. .002" of interference
at the corners of the peg, while the unfilled portions of the hole provide a
place for the displaced material.This is good design practice, but it does
point out that the grabs must be properly oriented before they are pressed
in place; ones the corners dig into the circumference of the hole, it will
be either difficult or impossible to twist them straight. If this is a
problem, the holes can be increased to .024" diameter, and CA used to fill
the gaps and lock the mounting peg in place.

Those who were hoping to use the really fine Kadee boxcar ladders on other
projects are going to be disappointed, unless they have a drill that drills
rectangular holes. Kadee has chosen, wisely, as far as I'm concerned, to
make the mounting pegs rectangular, .024" x .044". This allows a much
stronger mounting than round pegs could provide, and ensures that the
ladders remain straight, but the difficulty of generating the rectangular
slots in a model that wasn't molded with them in place is going to preclude
using these ladders on other projects. Because of this, I haven't bothered
to post the slot dimensions.

These are indeed wonderful parts. The grab irons and ladder rungs measure
just .010" in diameter, smaller than the .012" wire that is commonly used in
HO scale for these parts. The minimum diameter for these parts on the
prototype is 5/8", which scales to .007", but some prototype parts are made
from larger stock. The Kadee rung scale to just a bit larger than 7/8", not
far from the mark.

Dennis Storzek










=======
Email scanned by PC Tools - No viruses or spyware found.
(Email Guard: 7.0.0.21, Virus/Spyware Database: 6.18570)
http://www.pctools.com <http://www.pctools.com/?cclick=EmailFooterClean_51>
=======





=======
Email scanned by PC Tools - No viruses or spyware found.
(Email Guard: 7.0.0.21, Virus/Spyware Database: 6.18570)
http://www.pctools.com/
=======


Tim O'Connor
 

Dennis

One could try drilling a small round hole, and then using a 4-sided
steel reamer of a slightly larger dimension and just forcing it into
the round hole. Because the material is styrene it should deform and
provide a nearly square hole for the ladder mounting pins. (I assume
people are doing this with styrene carbodies. Don't know if resin would
deform the same way.)

Tim O'Connor

Those who were hoping to use the really fine Kadee boxcar ladders on other projects are going to be disappointed, unless they have a drill that drills rectangular holes. Kadee has chosen, wisely, as far as I'm concerned, to make the mounting pegs rectangular, .024" x .044". This allows a much stronger mounting than round pegs could provide, and ensures that the ladders remain straight, but the difficulty of generating the rectangular slots in a model that wasn't molded with them in place is going to preclude using these ladders on other projects. Because of this, I haven't bothered to post the slot dimensions.

These are indeed wonderful parts. The grab irons and ladder rungs measure just .010" in diameter, smaller than the .012" wire that is commonly used in HO scale for these parts. The minimum diameter for these parts on the prototype is 5/8", which scales to .007", but some prototype parts are made from larger stock. The Kadee rung scale to just a bit larger than 7/8", not far from the mark.

Dennis Storzek


Paul Lyons
 

Hi Schuyler,
Thought you would be Lyle! CBC says 8" max from the end to the bracket; 24" min. to 32" max fromt the centerline of the coupler to the bottom grab. That seems strange and I am doing some more research to see if that changed somewhere along the lin.
Paul

-----Original Message-----
From: Schuyler Larrabee <schuyler.larrabee@verizon.net>
To: STMFC <STMFC@yahoogroups.com>
Sent: Sat, Oct 22, 2011 11:20 am
Subject: RE: [STMFC] Kadee Bracket Grab Iron Hole Locations




I'm glad you posted Paul, as I have yet to receive Dennis' post on this
(Thank you Yahoo . . .)

I have what might be an ignorant question: Is the vertical dimension
between the two grabs at the left end of the car side uniform from car to
car? And is the dimension from the bottom of the car side a uniform
dimension from one car to another?

SGL

From: Paul Lyons
Sent: Saturday, October 22, 2011 1:54 PM

Dennis,
Thanks for all the effort! I hope you have the dimension between the
mounting pin holes on the side grabs and just forgot to put it on the
drawing? Or perhaps, it is the same dimension as the end grab?
Paul Lyons

-----Original Message-----
From: soolinehistory <destorzek@mchsi.com <mailto:destorzek%40mchsi.com>; >
To: STMFC <STMFC@yahoogroups.com <mailto:STMFC%40yahoogroups.com>; >
Sent: Sat, Oct 22, 2011 8:49 am
Subject: [STMFC] Kadee Bracket Grab Iron Hole Locations

As Promised, I have surveyed the mounting holes on a Kadee PS-1 body and
have uploaded dimensioned sketches to the FILES section at:

http://groups.yahoo.com/group/STMFC/files/Kadee_PS-1_Grab_Iron_Holes/

All dimensions are decimal inches, to four places where necessary. The
ordinate dimensions are relative to the center of the grab iron; it is up to
whoever develops a drilling jig to properly relate them to other features on
the car body.

The first sheet also shows the typical condition at the mounting pin / hole
interface. Whoever devised the old joke about putting a square peg in a
round hole obviously didn't design plastic parts, because that is exactly
what Kadee has done. The mounting pegs are .017" squares with a long tapered
lead; they are designed to be pressed into .020" diameter holes. A look at
the drawing shows that this combination yields appx. .002" of interference
at the corners of the peg, while the unfilled portions of the hole provide a
place for the displaced material.This is good design practice, but it does
point out that the grabs must be properly oriented before they are pressed
in place; ones the corners dig into the circumference of the hole, it will
be either difficult or impossible to twist them straight. If this is a
problem, the holes can be increased to .024" diameter, and CA used to fill
the gaps and lock the mounting peg in place.

Those who were hoping to use the really fine Kadee boxcar ladders on other
projects are going to be disappointed, unless they have a drill that drills
rectangular holes. Kadee has chosen, wisely, as far as I'm concerned, to
make the mounting pegs rectangular, .024" x .044". This allows a much
stronger mounting than round pegs could provide, and ensures that the
ladders remain straight, but the difficulty of generating the rectangular
slots in a model that wasn't molded with them in place is going to preclude
using these ladders on other projects. Because of this, I haven't bothered
to post the slot dimensions.

These are indeed wonderful parts. The grab irons and ladder rungs measure
just .010" in diameter, smaller than the .012" wire that is commonly used in
HO scale for these parts. The minimum diameter for these parts on the
prototype is 5/8", which scales to .007", but some prototype parts are made
from larger stock. The Kadee rung scale to just a bit larger than 7/8", not
far from the mark.

Dennis Storzek

[Non-text portions of this message have been removed]

=======
Email scanned by PC Tools - No viruses or spyware found.
(Email Guard: 7.0.0.21, Virus/Spyware Database: 6.18570)
http://www.pctools.com <http://www.pctools.com/?cclick=EmailFooterClean_51>
=======

=======
Email scanned by PC Tools - No viruses or spyware found.
(Email Guard: 7.0.0.21, Virus/Spyware Database: 6.18570)
http://www.pctools.com/
=======

[Non-text portions of this message have been removed]







[Non-text portions of this message have been removed]


Craig Zeni
 

Or, you can use my method...

I drill the holes with a #72 bit (taking locations from a Kadee car). I drill through, and apply liquid styrene cement from the back if possible. I give it 10-15 seconds to soften, and then gently push the ladders into place. The softened styrene pushes out of the way or out the back - rarely does any come up under the ladder. I just finished up a TMFTL* car and had to mount four new half ladders on the ends and corners. Mounted them all this way, and have mounted Kadee ladders to Intermountain PS-1s this way as well.

Craig Zeni
Cary NC

*TMFTL - Too Modern For This List :)

On Oct 22, 2011, at 7:52 PM, STMFC@yahoogroups.com wrote:
5d. Re: Kadee Bracket Grab Iron Hole Locations
Posted by: "Tim O'Connor" timboconnor@comcast.net cf5250
Date: Sat Oct 22, 2011 11:25 am ((PDT))

Dennis

One could try drilling a small round hole, and then using a 4-sided
steel reamer of a slightly larger dimension and just forcing it into
the round hole. Because the material is styrene it should deform and
provide a nearly square hole for the ladder mounting pins. (I assume
people are doing this with styrene carbodies. Don't know if resin would
deform the same way.)

Tim O'Connor



Those who were hoping to use the really fine Kadee boxcar ladders on other projects are going to be disappointed, unless they have a drill that drills rectangular holes. Kadee has chosen, wisely, as far as I'm concerned, to make the mounting pegs rectangular, .024" x .044". This allows a much stronger mounting than round pegs could provide, and ensures that the ladders remain straight, but the difficulty of generating the rectangular slots in a model that wasn't molded with them in place is going to preclude using these ladders on other projects. Because of this, I haven't bothered to post the slot dimensions.

These are indeed wonderful parts. The grab irons and ladder rungs measure just .010" in diameter, smaller than the .012" wire that is commonly used in HO scale for these parts. The minimum diameter for these parts on the prototype is 5/8", which scales to .007", but some prototype parts are made from larger stock. The Kadee rung scale to just a bit larger than 7/8", not far from the mark.

Dennis Storzek


Dennis Storzek
 

--- In STMFC@yahoogroups.com, Paul Lyons <cobrapsl@...> wrote:


Dennis,
Thanks for all the effort! I hope you have the dimension between the mounting pin holes on the side grabs and just forgot to put it on the drawing? Or perhaps, it is the same dimension as the end grab?
Paul Lyons
The side and end bracket grab drawings are done with ordinate dimensions, Paul. The number on the end of the dimension line is the distance that line is from the center line, which is labeled "000" to indicate it's the origin. In the case of the side bracket grab, the holes are .1035" to each side of the center, or .207" apart. The end bracket grab is a bit longer, with the holes .111" from centerline, or .222" apart. Ordinate dimensioning is common on tool drawings, since without need for arrowheads, etc, it really helps to reduce clutter, and the toolmaker is typically relating all the dimensions to one point, typically the center of the tooling insert. In this case it's handy because all the holes will be a repeating unit; locate the desired center points of the grab irons, make the related holes into a block, or group, or whatever your CAD software calls it, and drop them on each center point of the grab.

I'm not getting into where the grabs should be located on the car, because it can be different for different prototypes. The dimensions are typically specified from top of rail, and so will not relate to the edges of the sills, etc. the same on all cars. The AAR recommendations have been published in multiple places; several times in the Car Builder's Cyclopedia.

Dennis