Date   

Re: Accurately scaled tank cars?

Thomas Baker
 

Group,

I try to coax a relative into moving from hi-rail to scale. I have modified some of his hi-rail cars that are scale or very close to it with more realistic graphics using proper decals. Since I do not model in O, nor do I have access to items in that scale, I am wondering whether Lionel tank cars are even close to scale. Perhaps, if they are, a member has transformed such a car into something looking more realistic. than what comes from the factory.

Tom Baker
________________________________________


Re: G&F Hoppers

Charles Hostetler
 

--- In STMFC@yahoogroups.com, Chris Dills <cddx@...> wrote:

Let me rephrase that, Why would a car with 41' length overall only be classified as a 34' car. If memory serves me correctly, a car is classified by the inside length of the load carrying area. Most if not all hoppers have sloped end sheets that taper up to the ends of the cars. So why would 7' of the car not be listed? Is that normal?

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

The other 34' IL hoppers in that list I posted this morning had an OL of 35', a difference of 1' which appears to be typical for hoppers in general. So the G&F cars with a difference of 7' between IL and OL are not like the others in that respect.

This is just a guess, but the ACL and SAL both had open hoppers for carrying wet rock phosphate (and sand). They were rebuilt from regular hoppers with shortened interior and a platform near the top of each end for personnel to stand on. I wonder whether the G&F hoppers might have been of a similar design and use...

I'll send you scans of the G&F ORER pages as soon as I can get back home to my scanner.

Regards,

Charles Hostetler


G&F covered hoppers

Chris Dills <cddx@...>
 

Here's a photo from my Fotki site of G&F #12082 which is one of the cars reported to be built in the Douglas, GA shops. I've heard a rumor that they may have been built or rebuilt from open hoppers. Does anyone know more about this?


Re: G&F Hoppers

Chris Dills <cddx@...>
 

Let me rephrase that, Why would a car with 41' length overall only be classified as a 34' car. If memory serves me correctly, a car is classified by the inside length of the load carrying area. Most if not all hoppers have sloped end sheets that taper up to the ends of the cars. So why would 7' of the car not be listed? Is that normal?


Re: G&F Hoppers

Chris Dills <cddx@...>
 

Charles,

Thanks for the info!

Question though, why would they be classified as 34' cars if the overall was 41'? I'm guessing that is over end sills? or would that be over coupler faces? That kind of cubic foot would seem to be correct for a 40'-41' foot car. Could you hazard a guess as to why they would reclassify them with 568 less cubic foot? You would have to remove about five and a half feet from the length of the car to decrease the cubic footage by that amount. Which I'm guessing they didn't really do. Any ideas?

THANKS!

-Chris Dills


Re: Model Shapeways Tank Car Frame

Tom Madden
 

Sorry, I missed the point that Aaron wasn't asking about the ATSF tank car frame.

Tom Madden

--- In STMFC@yahoogroups.com, "pullmanboss" <pullmanboss@...> wrote:

Aaron Gjermundson asked:

How do the Shapeways parts look when painted?
Aaron, the Shapeways masters shown in the photos (underframe and multiple dome structure) *are* painted. Otherwise you'd have a hard time seeing the surface detail. As received they are translucent white and slightly sticky due to residual wax. After ultrasonic cleaning in hot (but not uncomfortably hot) water with a bit of dishwashing liquid added, they are frosted. I sandblast, not to clean, but to even out the surface finish. Shapeways Frosted Ultra Detail material, unpainted, has a chemically active surface. It takes paint readily, but silicone rubber will bond to it. You won't be able to get an unpainted Shapeways master out of the mold without tearing the mold or breaking the master. Usually both. That's why, with Shapeways, I order two of everything.

(Forgive the overexplanation, but Aaron is an accomplished resin caster and I want to save him some grief.)

Tom Madden


Speaking of Kits FS

Greg Martin
 

Guys,

I am continuing to thin out the fleet of items that will never make it of
the "to do" list and here are a couple items.
1. Red Caboose #RC-7044-6 Central of New Jersey 40-foot (X29) steel
sheathed boxcar $20.00
2. Red Caboose #RC-8024-4 M&StL "Peoria Gateway" ARR 1937 40-foot
boxcar $20.00
3. Red Caboose #RC-8602-5 Colorado Southern ACF 4/3/1 end 8-foot door
boxcar $20.00
The above are all kits in the original boxes and still paper wrapped. Add
$2.75 for freight .

Please contact me OFF LINE ~ OFF LIST

_tgregmrtn@aol.com_ (mailto:tgregmrtn@aol.com)

Thanks,
Greg Martin

Eventually all things merge into one and a river runs through it.
Norman Maclean


Re: SMMW SAL B7 Box

Larry Sexton
 

John,



What, if anything, can you tell me about the current status of these SAL B-7
, AF-1 and AF-2 boxcars?



Larry Sexton



From: STMFC@yahoogroups.com [mailto:STMFC@yahoogroups.com] On Behalf Of John
Degnan
Sent: Tuesday, November 20, 2012 5:01 PM
To: STMFC@yahoogroups.com
Subject: Re: [STMFC] Re: SMMW SAL B7 Box





Agreed. And for the record...

I was the one who did all the foot-work and research (to find the original
Pullman drawings for the SAL B-7). But, as there has already been some
mention about the SAL AF boxes, I can tell you that I was planning to push
to have the SAL AF-1s/2s done next, as I am sure that my source for the B-7
drawings will surely, also have the AF drawings. Jim has already said he
will do the AF boxes in S scale (my other scale)... so they would surely
have been done in HO as well had the market not lost him.

But you know the old saying... money talks and... well, you know. So talk to
Gary Wright about the AF boxes and see if he will get them done for us. They
were nearly identical, it not identical, so at LEAST six of them are already
spoken for by me.

John Degnan
Scaler164@comcast.net <mailto:Scaler164%40comcast.net>
Scaler187@comcast.net <mailto:Scaler187%40comcast.net>

----- Original Message -----
From: Allen Cain
To: STMFC@yahoogroups.com <mailto:STMFC%40yahoogroups.com>
Sent: Tuesday, November 20, 2012 10:36 AM
Subject: [STMFC] Re: SMMW SAL B7 Box

It is an unfortunate loss to us HO scale southeastern modelers that Jim has
chosen to drop out of the HO market, again, due to lack of sales. Just goes
to show that if you like something, you better buy and support the
manufacturer!


Re: G&F Hoppers

Charles Hostetler
 

--- In STMFC@yahoogroups.com, Chris Dills <cddx@...> wrote:
Here's another hopper question; In the attached photo is hopper #12017 with built date stenciled 9-23 which is part of the 26 hoppers mentioned in the 1959 and 1960 OER's here on Lee's site;

http://www.railgoat.railfan.net/other_cars/gf_cars/gf_roster/gf1959-01.htm

http://www.railgoat.railfan.net/other_cars/gf_cars/gf_roster/gf1960-04.htm

The OER's indicate that these were 1940 cubic foot cars. The lettering on the side indicates the car is 25xx cubic foot. The last two letters are unreadable to me, but the first two seem to be 25 for sure... {snip} They also only appear in the 1959 and 1969 OER's.

Hi Chris,

The series appears in the April 1957 ORER (page 7 item 11) as:

Hopper, All Steel
12001 to 12026
IL 34'
IW 9'4"
OL 41'
EW 9'10"
EH 11'2"
CAPY 2508 cu ft., 100,000 lbs.

and in the Jan 1958 ORER (page 7 item 11) as:

Hopper, All Steel
12001 to 12026
IL 34'
IW 9'4"
OL 41'
EW 9'10"
EH 11'2"
CAPY 2508 cu ft., 100,000 lbs.


and in the April 1959 ORER (page 7 item 11) as:

Hopper, All Steel
12001 to 12026
IL 34'
IW 9'4"
OL 41'
EW 9'10"
EH 11'2"
CAPY 1940 cu ft., 100,000 lbs.


All entries are identical except that in the April 1959 listing, the cubic capacity was decreased to 1940 cu. ft. If these entries are all describing the same cars, which seems likely to me, it could be that the G&F reclassified the cubic capacity for some reason.

Here are the HMs with 34' IL from the Jan 1958 ORER:

RPT Start Stop IL CuFt CAPY #
DL&W 83300 83799 34 2151 100,000 451
DL&W 85000 85499 34 2151 100,000 422
L&N 186000 186299 34 2092 100,000 208
CG 21500 21699 34 2180 100,000 190
DL&W 85000 85499 34 1850 100,000 65
DL&W 83300 83799 34 1850 100,000 45
G&F 12001 12026 34 2508 100,000 26

Regards,

Charles Hostetler


Re: Model Shapeways Tank Car Frame

Tom Madden
 

Aaron Gjermundson asked:

How do the Shapeways parts look when painted?
Aaron, the Shapeways masters shown in the photos (underframe and multiple dome structure) *are* painted. Otherwise you'd have a hard time seeing the surface detail. As received they are translucent white and slightly sticky due to residual wax. After ultrasonic cleaning in hot (but not uncomfortably hot) water with a bit of dishwashing liquid added, they are frosted. I sandblast, not to clean, but to even out the surface finish. Shapeways Frosted Ultra Detail material, unpainted, has a chemically active surface. It takes paint readily, but silicone rubber will bond to it. You won't be able to get an unpainted Shapeways master out of the mold without tearing the mold or breaking the master. Usually both. That's why, with Shapeways, I order two of everything.

(Forgive the overexplanation, but Aaron is an accomplished resin caster and I want to save him some grief.)

Tom Madden


Re: Model Shapeways Tank Car Frame

npin53
 

How do the Shapeways parts look when painted?

Aaron


Re: 3D Printed ATSF Tank Cars

Gene <bierglaeser@...>
 

Tom,
I'd like to echo Rob Kirkham's comment, "Yes this is very nice work Tom and I appreciated your explanation of how you
went about certain steps." Frankly, I am very impressed both with the quality of your work and the lucidity of your explanations.
Gene Green


Re: 3D Printed ATSF Tank Cars

nvrr49 <nvrr49@...>
 

--- In STMFC@yahoogroups.com, "pullmanboss" <pullmanboss@...> wrote:
"In the trade, the consumer-grade 3D printers are called "computer controlled hot glue guns".
Tom Madden>
The perfect description! I had never heard that before, but I will be using that in my clinic.

Kent in KC
nvrr49.blogspot.com


Re: 3D Printed ATSF Tank Cars

North Model Railroad Supplies <nmrs@...>
 

Wow Tom,

Very neat work.

Can't wait for the commercial offering -J

Cheers

Dave North


Re: Sinclair billboard tank cars

switchengines <jrs060@...>
 

Hi Jack,

I can understand your interest in the Sinclair cars as I'm a heartland
modeler also, and they had a huge marketing presents in that area, it's always
the best choice to pick the petroleum companies common to the area your
modeling. And you say your "in O scale unfortunately", I would disagree with
that as your in the scale I should be in!
The AC&F Sinclair 10k insulated cars in question were in number
series SDRX 26100 to 26199, and no the number of the car in the photo was
not distinguishable. Your correct in that data is on the right side of the car
under the initial and number, but that's always the nominal capacity and light
weight (tare) of the car, which is not going to be specific to the builder of the
car. What we as modelers need to focus on (without getting to technical here)
is the tank specific data on the right hand side of the tank. This is going to call
out the type/class of the car, it's tank builder and date, and also the safety
valve test dates along with that of the tank, also test dates of specialty items
such as heater pipe coils. This stuff is going to be car specific (builder and
type/class) and needs to agree with the car we are applying the decals to. To
put a point on the hole thing, you need to know more than most modelers
know about tank car builders and types.
I agree with you about needing "greater depth" in tank car decal sets,
but let's say we have come along way since the old Champ sets with incomplete
oversized data. May I suggest that you have a look at some of the Protocraft
decals on his website, Norman has put a lot of new stuff up of late and even
gone back and corrected the colors in the Staley car sets. The Black Cat sets that
Allen is offering in HO scale are very good, and he deserves just credit for doing
a great job with them.......he's got the best GATX and Sinclair set out there in HO
for us "small" size modelers.

Jerry Stewart

--- In STMFC@yahoogroups.com, "moonmuln" <jack.f.mullen@...> wrote:

Jerry,

Your remarks caught my interest as I have a need for a couple Sinclair cars (in O scale unfortunately). A couple questions interpolated below.

Jack Mullen

Jerry Stewart wrote:

Allen, my friend, I would be more than happy to work with you on this project also.
The photo in question of the Sinclair AC&F 10k type 21 Insulated car was in a bunch
of shots that the late Bill Raia had acquired. Unfortunately it's was at an acute angle
in the photo, but you could see that it "appeared" to be painted in the same layout as
the all black Sinclair cars, just light colored from the sheathing batten at the bottom
of the tank upwards.
Could you distinguish the car number in the photo?

It looked to me as if they just used the same stencils as the all
black cars, just revising the colors? You are aware that if you do this to your present
Sinclair lettering set you would have to revise the tank data on the left side of the
?? Left side only? Isn't the tank data on both sides?

A set of assorted tank data with various mfrs, tank classes, dates and capacities would be great to have. AFAIK nobody has produced one.

car to reflect the proper AC&F information. I hate to say it, but so many decal sets
for tank car miss this critical point,
And including rptg mks and numbers for the underframe would be nice too.

and modelers screw-up the lettering all the
time.
Guilty as charged, I'm sure.

I personal don't think the lettering is any other color but black on the light tank
color, and I have my doubts if the cars every became all black as the model is before
the Sinclair fleet was sold off to Union Tank Line? There are a bunch of mistakes in
the lettering of the Proto 2k tank cars and this may be just another one of them.You
should have my e-mail if I can be of any further help.


Re: G&F Hoppers

C.D. <cddx@...>
 

--- In STMFC@yahoogroups.com, Chris Dills <cddx@...> wrote:
They also only appear in the 1959 and 1969 OER's.>

Sorry, that should've said 1959 and 1960.


Re: 3D Printed ATSF Tank Cars

Robert kirkham
 

Yes this is very nice work Tom and I appreciated your explanation of how you
went about certain steps. Funny this thread is going on at the same time
the topic of kits no longer being available runs. I suppose the medium
matters to cost and convenience, but I feel very hopeful about the resin and
scratch build side of the hobby.

Rob Kirkham

-----Original Message-----
From: O Fenton Wells
Sent: Saturday, July 20, 2013 10:31 AM
To: STMFC@yahoogroups.com
Subject: Re: [STMFC] Re: 3D Printed ATSF Tank Cars

Pretty awsome Tom! I tip my hat to you. Well done.
Fenton Wells

On Sat, Jul 20, 2013 at 12:23 PM, pullmanboss <pullmanboss@yahoo.com> wrote:

**


Many thanks for all the kind words, both on list and via private email.
I'll try a catch-all response to clarify a few things and answer the
questions.

The parts in the photos before the prototype shot of the running board
supports are all 3D printed masters with Archer rivets added. The parts in
the last two photos (the one showing all five parts and the one showing
them dry-fitted) are first generation resin castings made from those
masters. Those first generation castings will become production masters
after I add a few more details and make sure everything fits properly.

From my standpoint as a resin caster the original 3D printed part only
needs to get me through the Archer rivet application stage. At that point
I'll make a mold and work with resin castings from then on. There are two
reasons for this. First, the 3D printing processes that are capable of
rendering the level of detail shown in my photos use materials that are
much too brittle or unstable for end-product use, and the processes that
do
use suitable materials can't render the required level of detail. Second,
Archer rivets are wonderful, but they *will* chip off with careless
handling and, in my view, aren't trustworthy on a master from which 15 or
20 molds might be made. So my designs allow for at least two generations of
mold and casting shrinkage, and I use first generation resin castings
rather than printed originals as production masters.

Yes, the idea is to market two resin kits, one of which will make a Tk-G
or Tk-H, and the other to make either a Tk-I or Tk-J. Each kit will have a
tank with appropriate details and two domes. I intend to do the later
versions of the Tk-G and -H, with center tank anchors, rather than
as-delivered with head blocks and diagonal tank hold-down straps. The
diagonal strap anchor castings on the top of the tank will be there, of
course. A few things have to be worked out - the running board supports,
which in this design are cosmetic rather than structural, and the running
board steps might best be made of brass, but whether from formed strip or
photo-etching remains to be determined.

As Kent Hurley indicated, these parts were not made on $1600 machines. Or
on $16,000 machines. As many of you know, in my post-retirement career I
consult part time for a local rapid prototyping company and have access
(but not free access) to some pretty amazing technology. We can make parts
using stereolithography (SLA), selective laser sintering (SLS) and
PolyJet.
We don't yet have any MultiJet machines (like PolyJet but with higher
resolution), so I use Shapeways for that technology. At this stage of
their
development I wouldn't consider buying any consumer-grade 3D printer. They
do have a lot of gee whiz appeal and are great for making decent 1:1
objects and shapes, but in this hobby we make miniatures, not full-size
objects. (In the trade, the consumer-grade 3D printers are called
"computer
controlled hot glue guns".) Pay attention to the jewelers who use 3D
printing. Their needs are similar to ours, so follow their lead.

Now if you will indulge a bit of philosophy…. I am a competent modeler,
have become passably competent in 3D CAD, and have expertise in resin
casting and mold making. When it comes to casting I can look at a part,
visualize how the resin will flow, where the parting line needs to be,
where the gate and vents should be located, and how the part should be
oriented in the mold. I've also been intimately involved in the design of
a
very complex product line, the Branchline heavyweight Pullman kits. So I
have a pretty good view of the whole process, from concept through
manufacturing and final assembly. My gripe with resin kits in general is
that the patterns are created but not designed, and the kits themselves,
the aggregate collections of parts needed to create models, are seldom
engineered with any consideration for ease of assembly. That's
understandable because, traditionally, patterns for resin casting have
been
created by expert scratch builders. And scratchbuilding involves a lot of
"make it up as I go along". Also, even with one-piece bodies, many parts
are still made by flat casting and you can't include mounting bosses or
alignment keys on the backs of flat cast parts.

Tank cars are considered very difficult resin kits to assemble. I've tried
to break a complex model into parts that are straightforward to cast, and
include registration and alignment features. All those notches, grooves,
posts and apertures in the parts have a purpose. Drill and tap the bottom
of the dome mounting boss and the subassembly of upper & lower tank
shells,
running board and dome can be held together in perfect alignment with a
single 1-72 machine screw. The tank supports that mount on top of the
underframe ("fiddly bits" awaiting application of Archer rivets) are keyed
to it, and the underframe is keyed to the lower tank shell. Holes will be
spotted for grab irons and handrail posts, and a forming jig provided for
making the offset bends in the end handrails. You'll still have to remove
flash from the parts, but once that's done the assembly should go quickly.

Might be a Prototype Rails clinic in all this - Designing for 3D Printing,
including an overview of the 3D printing processes appropriate to our
hobby....

Tom Madden




--
Fenton Wells
5 Newberry Lane
Pinehurst NC 28374
910-420-1144
srrfan1401@gmail.com


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



------------------------------------

Yahoo! Groups Links


G&F Hoppers

Chris Dills <cddx@...>
 

Hey guys, I'm fairly new to the group and have been kind of lurking around reading old posts.

I'm interested in modeling the G&F during the transition era. During my research, I've stumbled across several photos of cars that are not on any OER's or anywhere else that I can find mention of. There are also some cars listed that there doesn't seem to be much information about such as the 3 large 2755 cubic foot hoppers that Marty posted about a few days ago.

Here's another hopper question; In the attached photo is hopper #12017 with built date stenciled 9-23 which is part of the 26 hoppers mentioned in the 1959 and 1960 OER's here on Lee's site;

http://www.railgoat.railfan.net/other_cars/gf_cars/gf_roster/gf1959-01.htm

http://www.railgoat.railfan.net/other_cars/gf_cars/gf_roster/gf1960-04.htm

The OER's indicate that these were 1940 cubic foot cars. The lettering on the side indicates the car is 25xx cubic foot. The last two letters are unreadable to me, but the first two seem to be 25 for sure. This seems like too much cubic foot to be in a 34' ribbed side car. But the overall size of the car is not readily apparent from the photo. This photo albeit in a less angled view is on the cover of the October 1960 G&F magazine but is only about half the size of a business card. In the photo it does appear to be at least a 40' car. Is it possible that this might be a different size than the rest of the cars? Or could there have been several sizes amongst the cars? Or is the car just "mis-labeled"?. You can see where the previous road name was painted over with a stripe to hid the lettering. They also only appear in the 1959 and 1969 OER's. So it's possible that they may have been leased but haven't found any information indicating for sure.

I'm interested in modeling some of these cars, but have never seen a hopper with 7 panels. Can any of you identify the maker or possibly a previous road that owned them? Are there any known HO scale models of such a car or similar cars? Thanks! -Chris Dills


Re: end of kits

StephenK
 

If you are concerned about new modelers not building kits, I suggest you recommend an Accurail boxcar kit to them. Maybe even buy them one. After he (or she) builds it--and it really isn't a problem for anyone with even a little skill--you can discuss weathering, detailing, etc. I think that once a modeler gets a few of these under his (or her!) belt, they will realize the joy of building.

The cars are nice, and they run well, and the price is right.

Last month I picked up a N&W combo door box from my LHS. I am aware of the shortcomings of the model but I liked the paint scheme. I added cushioned coupler pockets (from Walthers) and some cross0over walkways from my scrap box. A little paint, a little glue, a little weathering, and I have a nice car for not much money.

Steve Kay

--- In STMFC@yahoogroups.com, "EdwardM" <ed_mines@...> wrote:

I think the greying of model railroaders in general fueled the shift from kits to RTR.

Many modelers end up with a closet full of kits; they then progress to buying less and spending more for each item. RTR is preferable to kits which may never get built or can't be built in the first place.You can put RTR on your layout or on a shelf. Kits stay in the box forever.

Together, this group has enough unbuilt kits to stock several hobby shops.

Kits have always been slow movers - if the buffs don't buy them all up they can stick around hobby shops for years.

Hobbies for men never sold anything more complicated than blue box screw driver kits. The owner knew how to make money.

We are lame ducks for (1) being interested in the steam era & (2) liking to build models. Both interests seem to be dying out.


Re: 3D Printed ATSF Tank Cars

O Fenton Wells
 

Pretty awsome Tom! I tip my hat to you. Well done.
Fenton Wells

On Sat, Jul 20, 2013 at 12:23 PM, pullmanboss <pullmanboss@yahoo.com> wrote:

**


Many thanks for all the kind words, both on list and via private email.
I'll try a catch-all response to clarify a few things and answer the
questions.

The parts in the photos before the prototype shot of the running board
supports are all 3D printed masters with Archer rivets added. The parts in
the last two photos (the one showing all five parts and the one showing
them dry-fitted) are first generation resin castings made from those
masters. Those first generation castings will become production masters
after I add a few more details and make sure everything fits properly.

From my standpoint as a resin caster the original 3D printed part only
needs to get me through the Archer rivet application stage. At that point
I'll make a mold and work with resin castings from then on. There are two
reasons for this. First, the 3D printing processes that are capable of
rendering the level of detail shown in my photos use materials that are
much too brittle or unstable for end-product use, and the processes that do
use suitable materials can't render the required level of detail. Second,
Archer rivets are wonderful, but they *will* chip off with careless
handling and, in my view, aren't trustworthy on a master from which 15 or
20 molds might be made. So my designs allow for at least two generations of
mold and casting shrinkage, and I use first generation resin castings
rather than printed originals as production masters.

Yes, the idea is to market two resin kits, one of which will make a Tk-G
or Tk-H, and the other to make either a Tk-I or Tk-J. Each kit will have a
tank with appropriate details and two domes. I intend to do the later
versions of the Tk-G and -H, with center tank anchors, rather than
as-delivered with head blocks and diagonal tank hold-down straps. The
diagonal strap anchor castings on the top of the tank will be there, of
course. A few things have to be worked out - the running board supports,
which in this design are cosmetic rather than structural, and the running
board steps might best be made of brass, but whether from formed strip or
photo-etching remains to be determined.

As Kent Hurley indicated, these parts were not made on $1600 machines. Or
on $16,000 machines. As many of you know, in my post-retirement career I
consult part time for a local rapid prototyping company and have access
(but not free access) to some pretty amazing technology. We can make parts
using stereolithography (SLA), selective laser sintering (SLS) and PolyJet.
We don't yet have any MultiJet machines (like PolyJet but with higher
resolution), so I use Shapeways for that technology. At this stage of their
development I wouldn't consider buying any consumer-grade 3D printer. They
do have a lot of gee whiz appeal and are great for making decent 1:1
objects and shapes, but in this hobby we make miniatures, not full-size
objects. (In the trade, the consumer-grade 3D printers are called "computer
controlled hot glue guns".) Pay attention to the jewelers who use 3D
printing. Their needs are similar to ours, so follow their lead.

Now if you will indulge a bit of philosophy. I am a competent modeler,
have become passably competent in 3D CAD, and have expertise in resin
casting and mold making. When it comes to casting I can look at a part,
visualize how the resin will flow, where the parting line needs to be,
where the gate and vents should be located, and how the part should be
oriented in the mold. I've also been intimately involved in the design of a
very complex product line, the Branchline heavyweight Pullman kits. So I
have a pretty good view of the whole process, from concept through
manufacturing and final assembly. My gripe with resin kits in general is
that the patterns are created but not designed, and the kits themselves,
the aggregate collections of parts needed to create models, are seldom
engineered with any consideration for ease of assembly. That's
understandable because, traditionally, patterns for resin casting have been
created by expert scratch builders. And scratchbuilding involves a lot of
"make it up as I go along". Also, even with one-piece bodies, many parts
are still made by flat casting and you can't include mounting bosses or
alignment keys on the backs of flat cast parts.

Tank cars are considered very difficult resin kits to assemble. I've tried
to break a complex model into parts that are straightforward to cast, and
include registration and alignment features. All those notches, grooves,
posts and apertures in the parts have a purpose. Drill and tap the bottom
of the dome mounting boss and the subassembly of upper & lower tank shells,
running board and dome can be held together in perfect alignment with a
single 1-72 machine screw. The tank supports that mount on top of the
underframe ("fiddly bits" awaiting application of Archer rivets) are keyed
to it, and the underframe is keyed to the lower tank shell. Holes will be
spotted for grab irons and handrail posts, and a forming jig provided for
making the offset bends in the end handrails. You'll still have to remove
flash from the parts, but once that's done the assembly should go quickly.

Might be a Prototype Rails clinic in all this - Designing for 3D Printing,
including an overview of the 3D printing processes appropriate to our
hobby....

Tom Madden




--
Fenton Wells
5 Newberry Lane
Pinehurst NC 28374
910-420-1144
srrfan1401@gmail.com


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