ERIE DUNMORE STEEL CABOOSE PROJECT - Scratchbuilding, with a laser

Excellent work Jim. When will the lessons take place?

So, how many "kits in a bag" are you going to produce and sell?

Wow, very nice! That laser can save a lot of work.  The steps are exquisite.

Great project, JMusser...thanks for sharing it with us.  I'll be following your progress with great interest as an Erie "Dunmore" steel caboose has been on my wish list for quite a while now.  Unfortunately, I currently don't possess the skills or time necessary to tackle a custom-build project like yours.  Hmmm...maybe this could be my third masterpiece caboose from Brother Love.  What do you think, Malcolm??

Spectacular!  And I am not a fan of plastic models.  Maybe even ground-breaking?

If someone made G scale modern diesel kits in a bag, they'd save me a lot of work and frustration!

That's an impressive amount of progress. I am also interested in the G-39a PRR ore jennie, seems like nobody has made one in 3-rail or 2-rail O scale.

Very impressive. What do you use to cement the pieces together with acrylic vs. styrene?

If you made a complete kits with trucks, handrails, etc... for a decent price I would be interested in 4-6 kits. If you only do a semi-kit I'll probably have Malcom do a few for me. I don't have time to build. I'd either be sending the kit out to be done or having Malcom do them for me.

Excellent work Jim!!!!    I think a Penn Central Transfer caboose in S Scale should be in the rotation!!!!

@AGHRMatt posted:

Very impressive. What do you use to cement the pieces together with acrylic vs. styrene?

When I fabricate with acrylic I use methylene chloride. Micro Mark "Same Stuff" is essentially pure methylene chloride. The name based on the fact its supposed be the same as Tenax 7R now NLA.

I agree, first rate modeling here. I don't collect Erie but do like to build stuff. I may be in for one.

Pete

Dear Forum Members,

The Cherry Valley is very lucky to have Jim in our club. Jim is a master carpenter contractor and has the proper equipment to produce a number of items for production.

Jim,I hope I was to one to inspire you to do the G39 ore jennies. Just add the Crown Trucks from Atlas or RY models, decals by John Franz.

And you just can't have just one !!! 24 or 36 would make a neat unit train in PRR/PC/CR era.

john

Thanks all for the kind encouragement.  To clear things up a bit, I don’t have plans to produce this as a kit.  I use the term “kit” in the context of the prototype Erie Railroad - they purchased the pre-cut steel sheets and structural components (kit), and welded it together at their shops.  It was their design, they just outsourced the cutting of the steel - I’ve outsourced mine to a robotic laser.  

Glue - Gluing the .060 styrene that I am using to itself, is almost as hard as hand cutting the material.  They make a liquid adhesive that does the trick, except that it evaporates almost instantly so you have to use a needle applicator, and a bigger problem, it’s so nasty that it would probably kill the five brain cells I have left.  The only liquid model glue that I’ve come across that says it will work with acrylic on the label is Plastruct Plastic Weld (the orange bottles not the white).  Which is good, since it’s the cement I’ve enjoyed using for years.   Most liquid glues are formulated for styrene to styrene bonds, however, because Plastruct products come in styrene, ABC, Butyrate, and acrylic, they had to make something that could bond these to each other.   It’s still a bit sketchy bonding acrylic to acrylic.  If I was working with thicker material it would be easier, ie more surface area at glue joint.  With .060, you need to hold things steady for a bit while the glue works, however, using styrene square rods as a backer in the corner makes for a quick, solid joint.     The following photo shows the square rods - 0.125x.0.125  in corners and 0.125x0.312 along the bottom of the walls.  The bigger piece is used to make attaching the undercarriage with screws easy.  

The notches on the ends by roof are for another styrene rectangular shape.  The roof was welded to the body with this caboose, so there isn’t the typical slight overhang, but rather a slightly rounded edge.  My idea, and it might not work, is to glue the roof sheathing to the upper rectangular block and then round over slightly with sanding pads.  The whole assembly there will be easy to sand styrene.  

Adding the intermediate supports and cupola ends.  I might have overkilled this, again, since acrylic is very rigid and stable, but it can’t hurt I guess.   On the long side of cupola I have two frames - one against the cupola side and one just behind the double windows.  There is another frame against the opposite cupola side.  The ends get an abbreviated frame, due to lack of space with windows and doors along roof line (yet to be added)  All frames were notched for the roof joists and the styrene block along bottom edge by the laser.  All parts were also labeled by the laser.  On both of the experimental assemblies I installed one of the cupola sides facing the wrong way.  The outsides have weld lines around the window frames that need to face out, so I added labels on this version.  At bottom of photo is one of the spacers for the cupola sides, two of which are visible in upper right portion of photo.   There are also more simple, rectangular spacers on the longs side visible above and below the windows.  These spacers are to make everything self-aligning, and self-squaring.  There is very little that needs to be visually aligned while gluing.   It makes for fast construction.  Right now my estimate is about two hours of less start to finish, except for details like steps, handrails, etc.  

Spacers more visible in the above photo.  Note the labeling.

Windows and doors are cut from poly-backer, also called laser-board in some circles.  Poly-backer is around 0.020 thick.  The thinnest acrylic I can get is .060.  The laser will cut styrene, but it’s too soft and the edges aren’t crisp.  The doors are just a two part assembly using ACC glue.  The poly-backer adheres great to the acrylic with ACC also.  

I’ll leave you with the partially assembled body.  It’s easier to add the windows and doors  as I go along.   Note the weld-lines around the windows, and on the sides, pretty close to prototype locations.  Obviously,  more of a scribe than a weld, but if you were really nuts, you could glue a small styrene rod to the grooves to better simulate a weld line.  The corner is stepped intentionally for a .060 styrene quarter round rod (Plastruct #90893)   The prototype had rounded corners.   Also note the pre-drilled holes for all the grab irons.    That’s it for tonight.  

Jim 

I am with Jim.  Producing kits is a giant loser unless you are talking thousands with an assembly line.  I tried a "kit" Vanderbilt tender - ten dollars worth of brass, two hours of labor cutting, drilling, and packaging.  I made three, and kept one.

The offer I made was "build it and critique it, or return it, or send me $75".  I thought that was fair.  That was when $75 bought more than one tank of gas.

If you have the bucks to get Malcolm to assemble a kit, then you have the bucks to have him make it from scratch.  I get the feeling that assembly is about 80% of his workload.  I don't build in plastic, so that is unfounded opinion.

@jdunn posted:

Dear Forum Members,

The Cherry Valley is very lucky to have Jim in our club. Jim is a master carpenter contractor and has the proper equipment to produce a number of items for production.

Jim,I hope I was to one to inspire you to do the G39 ore jennies. Just add the Crown Trucks from Atlas or RY models, decals by John Franz.

And you just can't have just one !!! 24 or 36 would make a neat unit train in PRR/PC/CR era.

john

Depending on the price per kit, i too am in for several PRR G39's. O scale drawings can be found in a rails northeast magazine.

I finished the primary body assembly tonight, including installing the window frames.  

The undercarriage begins with the car bottom - note the pre-cut notches.  Again, these are to make the assembly fast and keep the parts aligned.  The two hexagonal holes on each end are to capture M2 nuts for easily attaching the Kadee couplers.  The nuts are trapped by the .020 frame flange and the platform grating.  

Cross pieces and two main beams are notched to mate with each other, and tabbed to insert into the car bottom.  The .020 under the beams is a single piece, also with same tabs and holes as bottom.

PRR Horseshoe Curve - Do you know the specific issue the plans for the G-39 are in?   I have a set, maybe the same ones, although they aren’t very detailed and resolution is low.    

Jim, what are you using to draw your CAD with?

The Model Train Magazine Index (free) is a good place to start.  Add it to your Internet Favorites.

The C&O Historical Society offers the complete Mainline Modeler Magazine archive on a searchable DVD.

The original TrainLife website offers many back issues as online readable PDFs.  Add it to your Internet Favorites.

HOSeeker.net offers scans of old kit instructions (mostly HO) and literature.  Add it to your Internet Favorites.  If you have kit instructions not found on the HOSeeker.net website, please consider providing them with a scan.

Thank you,

Old Goat

Chris - I use a program called V-Carve Pro, by VETRIC Software to draw and design the parts. It’s not something I’d go out and purchase as it’s designed for use with CNC machines.   Really, any program that can generate a vector file will work - Autocad, Adobe,  Corel,.....etc..   There are free ones too, but learning curves can be a bit higher.  You don’t actually need much,  just something that can draw lines in scale.   When I bought the laser, I also bought Corel, but it was overkill for what I needed, and would have had to spent some time learning.  I already was well versed in the V-Carve program for my cabinet shop, and it can export files as DXF (cad), so I just stuck with what I knew.    Once you have the vector file, you need a CAM program to create code to actually run the laser (not as complicated as it sounds)     The program I use, and which came with the laser, is called RDWorks.  RDWorks and the laser are all a straight from China in a crate deal, but the software is very intuitive and easy to use, surprisingly, except all the pop-up windows are in Chinese.  Sooner or later I’ll be able to ready “file successfully saved” in Mandarin.   The RDWorks program also has a 2d CAD component that could be used to draw.  The laser only understands the metric system, so drawings are done in millimeters.   I blow up plans to O-Scale, and just measure them with a metric ruler.   We use metric a lot in the cabinet shop, and even to layout out things on job sites.  It’s honestly much easier to use, and easier to be more precise using it, compared to doing our typical thousands of fractional calculations a day.   In woodworking, precision to one mm is between a 1/16 and 1/32 - pretty good, and you never see a fraction.   The following is the V-Carve drawing of the Erie caboose parts.

https://ogrforum.com/...4#146001354953562884

Thanks for the explanation. I’m versed in creating vector and .dxf files, so exporting to CAM is a snap.

and I agree working in metric is so much simpler. Mandarin I’m not so sure!

Well, since everyone wants to make a "kit", $75 to whom ever can make a Milw SDL39. Thanking you in advance.

Dick

Work was busy for past week, so not much work done on Erie caboose.  I finished most of the major components on the under frame and began installing the roofs.

The frames are all self aligning, so construction is fairly easy.  The beam flanges are cut from 0.020 styrene - one installed first with holes for tabbing, and then the second over the acrylic beams.   I inserted styrene blocks at the truck attachment holes to accept screws.  

Testing coupler height.  You can see the M2 nuts that are contained by the flange under the car, and grating/porch floor to be install on top.  

Your work shows excellent craftsmanship using state of the art manufacturing techniques. 

  Incredible accuracy with no moulds or dies to wear out. Very nice

Al

I finished glueing on roof panels and rounding the edges.  The roof of the prototype was welded to the car sides and edge was sort of just a big round over, with no overhang.  This is a little harder to do on a model than your typical roof with a slight overhang.  If you remember, my frames had a notch for a large styrene block.  The block was slightly larger than the notch and was shaped with sanding sticks to match the curvature of the roof framing.  It also adds a nice styrene to styrene bond at the corners.   The roof panels were cut from .030 styrene on the laser, and the locations of the roof walk supports were engraved.  Again, this saves on measuring and marking with a pencil, and the laser is more accurate than I can be.   The corner styrene block/roof sheet is rounded over with sanding sticks.  

Photo above shows 1/16 z bar strips added as the walkway supports on the smaller roof. 

The roof walks were cut from poly backer, which is about .023 thick.  In o-scale, this would be a little over an inch in the real world.  Appropriate I think.   My initial walk is on the left, but comparing it to the photos of the prototype, the crosspieces had too much separation.   Speaking of the prototype, these cars were initially built with wood end platforms and roof walks, but,  the merged Erie-Lackawanna, replaced the wood on some of the cars with metal open grating.   Since I am building at least a handful of these, I will use wood on some.   This first car, is going to be a 1970’s Erie-Lackawanna.  

Completed roof walks.  

I realized tonight that I don’t have any brake gear for this car.  Tichy makes a very nice AB set in HO, but not in O.  Does anyone make a plastic brake gear set in O? Or do I need to get metal castings?  

Jim

Jim,

Grandt Line has what you need in plastic. Also Tom M. from the club has a stash of brake gear pieces in metal.

@J Musser posted:

PRR Horseshoe Curve - Do you know the specific issue the plans for the G-39 are in?   I have a set, maybe the same ones, although they aren’t very detailed and resolution is low.    

 

See your thread on the PRR G39. I posted all my mag covers and some drawings on that car. Yes I would love to purchase several kits if possible.

I was able to get an hour or so of model railroading in tonight.   Assembled and installed the steps, end platforms, etc.   Left to do is the brake gear, and all the grab irons, ladders, and railings.   I have to gather some materials and make up a few jigs for bending and soldering.  

Super job on those laser cut walkways ! And the steps !  Nothing beats making cars you want yourself . That's what O scale was all about for years . Over a few weeks in  spare time you make a car . Awesome .

It’s been awhile since I updated this thread.  I was distracted by the G-39/G-38 ore jennie project that is on another thread.  I fully completed one G-39 and one G-38, and have another 24 in various stages of construction right now, but I figured it was a good time to get back to the DUNMORE Caboose and wrap that up.    When we left of, most of the body was complete other than all the grabs, ladders and railings.  I also hadn’t touched any of the brake rigging under the car.   Part of my procrastination was due to a noticeable warpage of the acrylic/styrene underframe, which caused a slop in the end platforms that was noticeable.  I realized this was because the main beam, which would have stiffened the frame,  was cut short to make space for Kadee couplers.  To correct this, I separated the platforms from the rest of the car bottom, slightly inside the car.  This still allowed me to access the interior to install the window glazing after painting, but at the same time corrected the sloped end platforms, and improved overall construction.  Cutting through the acrylic base wasn’t fun and turned out a bit sloppy, but I made the changes to the laser cut files to allow for this in future builds.    The car is mostly complete and will head into the paint shop soon.

I’m not sure whether I will letter this for EL or Erie.  I plan on building another three or four of these - at least one in EL.  Most of the cars were welded, but some of the earlier ones had riveted construction.  I might adjust the file to mark out for the riveted sections and try a few of those versions too.   Below are a few of the jigs I used for the ladders and railings - sort of experimental.  You may wonder why no brass strips for the ladder?  Two reasons, brass flat strip is getting hard to find, and, using the polybacker, the laser lays out and drills the holes precisely.  It worked for the style of ladder used with the DUNMORE caboose, but wouldn’t in many other cases.  

Excellent!

Dear Jim,

I have decided to call you Brother Jim in honor of Brother Love Malcolm !!!!

Really great work and we see it up front each week at the Cherry Valley club in Merchantville NJ.

John

Excellent work!

First car is complete and ready to ride the rails at the Cherry Valley Club. (On, I know, the wrong trucks).  

Some mistakes were made on this one - windows that are close to each other are too close slightly.  This was a result of sticking with the Erie plans for my drawings, and not comparing with photos of actual car.   The Erie plans weren’t shop plans, but more generalized for dimensional information.   The other mistake was not priming the underside of roofwalks prior to glueing them on.  My water based, Vallejo paint I sprayed on later, caused some deflection, although comparing it with photos, it is sort of prototypical.   Some other minor things, that will be fixed - slightly too large strip on roof platforms and ladder transitions.   Next two, already under construction, probably one Erie, and another EL.   Eventually want to add rivet strips to model the railroad’s first batch of these cars, which were riveted.  And probably a Conrail version or two.   The EL eventually added protective window screens to some or all of these cars, I’m working on the CAD files to laser cut these.  They make the car look horrible, but they are prototypical correct, especially for late EL and Conrail.  

the end platforms and roof walks are laser-cut phenolic? wow!

great work Jim.

Outstanding work, Jim!  Thanks for sharing it here with us.  Let me know if you ever decide to sell one!

Thanks Joe.  Yes Chris, it’s a phenolic resin board.  We get it in 4x8 sheets at our shop from our sheet goods suppliers.  It’s basically the backer used on Formica and other laminates.  I think the intended use it’s sold for is for adding as a backer to a veneer assembly - sort of a way to convert an intricate wood veneer design into more or less a sheet of Formica.   It’s .023 so nice and thin, scaling out in O Scale to a little over 1”  in real world.   The nice thing with that material is behind able to cut the walks and platforms exactly to what I need.  

@Lou N

Great work Jim, looks fantastic. Can't wait to see how the others come out.

~C. Vigs