PSC air hoses/angle cock brackets: Modeling notes.


Denny Anspach <danspach@...>
 

Please discard any preceding post under a similar title . It was
inadvertently sent when quite incomplete!

********

For a very long time I have been interested in improving the scale
detailing on the ends of our operating freight cars. Air hoses, angle
cocks and their brackets have been major players.

As the result of dissatisfaction with any acceptable HO plastic air
hose longevity under real time operating conditions (with/without plastic angle cocks), and-- the complete marketplace absence the most
common pattern of anglecock brackets used in our freight car era, the
idea arose on this list of using sturdy brass hoses and brackets .
However, although high quality brass hoses have been available from
PSC and Cal Scale for some time, until PSC was recently persuaded to
cast brackets made to Dennis Storzek's plans, and Dennis' and Chad
Boas' patterns, freight car detailers have had no effective strong way
of mounting the brass hoses to the model, at least in any fashion that
would stand up to more than a week or so in operations. This simply
recognizes the fact that the very rigidity of the brass hoses can
create an even more stiff lever arm that when pressed will almost
assuredly dislodge, break or send flying any intermediary plastic or
resin mounting angle cock bracket!

Here are some notes and suggestions resulting from applications of
these relatively new important details to recent freight car modeling
projects. Some understanding of working with these very fine brass
parts is helpful, not only to get the most out of these fine parts,
but also to reduce any wastage of these relatively costly items.

Brass Air Hoses: The PSC air hose (#3150) has a finely detailed angle
cock on each side of which are very short thin areas representing the
transitions to the fittings of the rubber hose on one side, and the
air pipe on the other. These tiny "choke points" represent very
fragile areas that in the process of careless handling leads to very
easy breakage before one even gets going. In my hands "careless handling" has meant not FIRMLY supporting these points with
needlepoint pliers or similar while either straightening or shaping
the air pipe; or more commonly, while also performing the gentle
shaping of the air hose itself into its characteristic drooping
compound curvature, i.e. a curve toward the vertical in the
longitudinal plane, and a curve toward the center horizontal in the
transverse plane (these respective curves of the two adjoining hoses
replicate the natural curvature described when the two are coupled
together).

The air pipe is a nominal .020" (#76), but variations make an
assumption of .021" (#75) a much safer proposition.

Brass Angle cock Bracket: The key to the use of this bracket
(#39156) is to successfully drill-out of the center of the U bolt that
wraps around the air hose brake pipe. The U bolt could not be cored
during the casting process, and although nominally there is instead a
dimple to capture the point of a #75 or #76 drill, individual casting
variations sometimes make the dimple almost impossible to locate.
After some excessive wastage charged off to a learning curve, I have
settled on the following drilling procedure:

1) Before clipping the brackets from their sprue, I center-punch each
of the U bolts while bracing the face of each U bolt on a supporting surface. This solved the drill-centering problem.

2) I then sharply clip off each bracket at the very base of its sprue,
the resulting "post" serving to provide a very effective mechanical
anchor into a drilled #71 hole into the underside of the freight car.
Using sharp nippers creates a clean undistorted "cut", while unsharp
cutters distort and enlarge the post.

3) I clamp each separated bracket into a vise drill out the delicate
U bolts. A drill press is superior for this task; but a Dremel tool
can also serve, as long as one has a steady hand. Holding a bracket
in one hand and attempting to drill it with a Dremel in the other CAN
be done, but in my hands, wastage was high, and it was inevitable that
I would slip and drill my hand in the process.

Once into it, these processes not only go very smoothly, but also very
fast. In this regard, once set up, I prepared as many of these
brackets and hoses as I was able at the time (20 cars at the last go-
round).

The brackets are then locked into a drilled #71 hole in the underside
of the freight car, the hole sited approximately 0.145" aft of the
coupler box striker plate. Although on the prototype the bracket is
sited directly along side the draft gear/coupler box, on models with
the semi-scale coupler boxes (Accumate Proto, Sergent) and scale
projection of the coupler heads beyond the striker plate, one has to allow some small added lateral space to avoid letting the attached air
hoses from interfering with the swing of the coupler head.

I successfully use both either ACC or Barge Cement in this process.
The tough resilience of Barge Cement has a theoretical advantage in
that it can probably better withstand the occasional knocks that these
stiff air hose assemblies are bound to receive in routine use.

Once the brackets are secured in place, then insert and secure the air
pipe ends of the hoses with their angle cocks into the angle cock
bracket. Remember that the longitudinal plane of the angle cock is to
be angled about 45ยบ toward the car center. Hose and bracket can be
secured in place most easily with ACC, but can also probably be
secured for eternity with a quick application of a small tip soldering
iron (the latter should only be attempted by those comfortable with
soldering such small pieces, especially considering the risk of
collateral car damage during the process).

Added comments: Whether or not the modeler will wish to keep
magnetic trip pins AND these new air hose assemblies will be a matter
of individual choice, in addition to one's own skills in managing to
keep these unyielding air hoses from mechanically interfering with the
trip pins. I do not use the trip pins, so they are either simply not
mounted during coupler assembly, or they are routinely clipped off.

I believe that the new availability of these hardy air hose assemblies
marks another significant move toward the goal of at last bringing
the ends of our scale HO freight cars into some semblance of
prototypical acceptability. These moves have been:

1) We have been firmly moving away from the conventional porcine
0.110" tread wheels of the past 70 years to the more visually-
acceptable 0.088" semi-scale wheels.

2) Close-to-scale narrow coupler boxes are now provided by Accurail
and Sergent, providing long-sought relief from the common gaping-ugly-
fish-mouth boxes that we have had to put up with for so long.

3) Along with the narrow boxes, both Accurail and Sergent also provide
integrated scale-size couplers with scale shank lengths that for the
very first time also allow an almost perfectly scale 29" striker-to-
striker coupler distance between cars. I cannot overemphasize the
importance of this when one observes our prototype cars actually _en
train_, closely spaced and with the satsifying illusion of coupling
air hoses now filling the space below the joined couplers.

4) Scale-sized couplers need no advocate. However, IMHO they have only limited visual value if they are not accompanied at the same time by
scale shank lengths and- they are housed in narrow coupler boxes.

I am attempting some photos and other graphic materials to place into
Files, and will do so when I succeed!

Denny













Denny S. Anspach MD
Sacramento

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