Large Scale Central

Modeling D&RGW Derrick OP

Modeling
#1

I’m thinking about trying to build a 1:20.3 (reasonable facsimile) model of this derrick. I’ve ordered the Quick Pic book and I also have drawings from other books. I can use PNG kits as a base. 1 MOW car and a flat for the idler. My prollem is the actual derrick and other parts. Has anyone tackled this? Any tips would be appreciated. If so I would be interested in “hiring out or contracting” the derrick itself if anyone is interested. Doesn’t have to be rivet counting perfect, just a non working model.

#2

An ambitious project, JB.
I’d suggest looking back through the forum.
I think last year’s Challenge had a smaller, very well done derrick.
Seems to me there have been others.
Ralph

#3

John, your buddy Ron built something similar last year.
http://www.largescalecentral.com/LSCForums/viewtopic.php?id=12705

#4
Randy McDonald said:
John, your buddy Ron built something similar last year. http://www.largescalecentral.com/LSCForums/viewtopic.php?id=12705
I forgot about this one. Beautiful work too. Ralph
#5
Randy McDonald said:
John, your buddy Ron built something similar last year. http://www.largescalecentral.com/LSCForums/viewtopic.php?id=12705
Dang, I thot Ron built a pile driver. Old Timers dizees. :) :) I'll ask Ron to bring his down this year, and while he is pre-occupied, I'll "Borrow it". :) :)
#6

And it’s really nice that Ron has left all the photos available a year later :smiley:

#7

Yes it is! I stole most of 'em and filed 'em for future reference.
Thanks, Ron!
I’ve been studying the drawings and I think I may be able to conquer the boom and tackle.
The idler flat and shack won’t be too hard to build.

#8

Is it done yet?

#9

John,
I will be bringing my derrick down to the May meeting. You can take all the pictures you like and ask all the questions you like. As for borrowing, not going to happen, sorry. Although it is a challenging project, if you just break it down into small parts it really isn’t all that hard. It’s like eating an elephant, one bite at a time. From all of the beautiful models that I have seen on these pages, including yours, I am sure that there are many others out there that could build this model if they had the desire.
Ron

#10

John,

I did exactly as you described about 6-7 years ago. I started with two PNG kits - a flat and a box. I ordered extra grab irons and detail parts from Phil (who is great to work with on these kinds of things) and a few random pieces of Ozark/Trackside to round out the needs. Using that, plus some stock brass rod, and scale lumber I was able to get the Derrick complete minus the “A” frame and the boom itself.

For those two parts, you do have options.

To begin, I would recommend building the flat (you will need a few extra bits of wood from the LHS to build the boom cradle) and then tackling the OP. The first major decision you will have to make is will you “shorten” the Boxcar sides and use the existing end from the kit to build the “house” (if so, it will be noticeably shorter than the prototype) or make your own sides (not hard at all). I took pre-scribed lumber and, using the PNG boxcar sides as templates, cut new “house” walls, but making each longer.

At this point, if you build up the house, along with the walkways, grabs irons, and add in the door and window detail (again, just scrap lumber bits) you shoudl feel pretty jazzed at the outcome - and the best part is, with the flat complete and the Derrick “roughed out” in mass… with the two sitting there in front of you in 1:20 the will to continue grows quite strongly!! :slight_smile:

From here - four options come in to play.

You can a) contact David Bailey at DJB who makes a photo-etch kit for the boom and A Frame… not cheap, but not too expensive b) contact Alan at GAL who has been experimenting with laser cut derrick booms (albeit not for OP, but he might be able to do a custom job for you without too much cost), c) wait for a kit or built-up kit to come along on the classifieds, train show, or ebay - it does happen, but only about once a year, or d) build it yourself.

Don’t let the A Frame scare you - some basic, cheap, LHS lumber will get you started - the key is the “metal” wrap/flashing on the wood. With little effort, you can cut thin sheets of styrene into shape and glue them on top of the wood (or better yet, use brass sheet if you have the tools). From here - its just a pinvise and a bucket load of PNG nbw castings (or HO track nails)… add in a bit of brass rod bent to shape coming off the A Frame (or, in my case old coat hangers from the Dry Cleaners!) and you really are almost home.

I think the only think you really need to consider is the boom - if you have the patience and budget is tight, I say build it up on the kitchen table. If you’ve got a few extra bucks, the DLB boom is amazing (and, at one point David would sell it soldered up… if he doesn’t anymore, then there is that to consider too).

All in all - good luck - I’d say that for the cost of 2 PNG kits, $25 bucks in LHS lumber and another $25-30 in extra PNG castings and the random Trackside bit, over the course of a weekend you can easily have all but the boom done sitting in front of you! (And when you do - it is amazing to see in person - big!)

As reference, other people to look for online are Dean Lowe, Dave Crocker and David Gormley who have all built OPs… And Paul Mora has had one or two kits over the years (and parts of kits) for sale… I also think Wayne Spence built an OP… I’ve seen photos of all of them - some here at LSC and also on MLS and 120me.

Finally, some links for you:
http://www.thegalline.com/index.html
http://sites.google.com/site/riograndemodelsuk/
http://www.djbengineering.co.uk/

Best of luck!

#11

John, you inspired me to commence the build on a ‘baby’ freelance derrick for a pseudo ‘2 foot’ narrow gauge. I simply based mine on leftover Bachmann centre cupola caboose parts. The idler car will also use a modified underframe from the caboose. Obviously nothing like the D&RGW “OP” but it will be a derrick for the occasional derailment.

(http://freightsheds.largescalecentral.com/users/tim_brien/_forumfiles/3zdera.JPG)

#12

Josh,
Thanks a bunch for the tips. I will prolly use brass gussets on the model. I’ll make use of OM “logging” pulleys and a few bits from them.
I already planned on sacrificing a PNG MOW car for the house.
(That way, I’ll have the other half for a Pile Driver to build someday.)
I will investigate all avenues for the boom.

Tim,
Glad I could help! :slight_smile:
Now you need a string of MOW cars…:slight_smile:

#13

I’m starting to gather parts for the project.
Now that I have my Quick Pic book, the close up photos of the “A” frame help immensely.
I also found out the boom didn’t swivel, so that helps as well.
Mini fasteners, brass rod and strips, various strips of wood.
I have the pulleys covered except for the big three spool at the end of the boom.
Whew…
Oh, and the boom itself. I think I will build it from brass and braze the X bracing myself.
Maybe. :slight_smile: :slight_smile: (Plastruct is a back-up. They have 9/16" channel. 24" long.)
Depends if I can find some brass 9/16 channel over 18" long. The long boom is 30’ long.
It does show a joint with gussets, but I prefer to work with one piece and use fake gussets.
This is gonna be phun.
And no, Rooster, it ain’t done yet!

#14

John, you are incorrect on one point, the boom did/ does swivel. If you look closely at the pictures in the Quick Pic book on page 12 and 13, note that the top of the center post in the A frame is rounded. When I examined OP in Chama in 2007, you could clearly see the rotation pin. Also on the lower photo page 14, note the horizontal pulleys at the base of the center post. These were to guide the cable to the vertical pulleys inside the beam.This was to keep them on the vertical pulleys when the boom was off center. On page 18, upper photo there is a good shot of the base of the center post and the attachment of the boom. Boom swing was limited to about 20 degrees each way and was controlled by block and tackle with rope attached between the base of the A-frame and the side of the boom about 2/3 of the way out. These lines ran through horizontal pulleys in the arms sticking out on the A frame. If you look closely at the upper photo on page 7, the block and tackle and line routing are clearly visible. If the pull was too much for hand work then the line would be wrapped around the gypsy drum on the winch inside. Interestingly enough, OP had no power of its own. The winches were powered by a small steam engine inside the control house, but it received its steam from the locomotive pushing the unit. There were also eyes on the end of the house where the derrick could be tied down to the pusher loco to allow it to lift more without up ending the unit. Also note on page 6, the large u-bolt in the deck above the step. This is where a couple of timbers could be put through and then the ends supported by blocking in order to keep OP stable when lifting off center. If you study the drawings in Sloan’s Hundred and ten years book, note that OP was built on a much more substantial car than the normal flat cars of the time. The tender car is a normal 20 ton flat.
If you want to duplicate it, there is a tremendous amount of detail that could be added to make this model an accurate depiction of the prototype.

#15

http://valleymodeltrains.com/catalog/product_info.php?products_id=5937

Scroll down to DJB 1:20.3 pics

#16

Ron,
My model will be a reasonable likeness.
The boys down at Chama wrote (on their forum) the boom was fixed and it ran with compressed air from the locomotive.
And it was originally built from a gondola.
But, hey, it doesn’t matter, right?
I’ve read several different descriptions during my research for info.
Over the years, D&RGW rolling stock and MOW equipment morphed more than once into different types of cars.

#17

John,
My model was also only meant to be a reasonable likeness, but to me there are certain things that define the model and need to be included in order to do this. The swinging boom is one of those items (in my opinion). The boys in Chama may have made the boom rigid, but I see two obvious problems with that and one of them would apply to the model as well. If the boom is fixed, then you can only lift things that are directly in front of the derrick, to me this really puts limits on the usefullness of the machine. This applies only to the real one or a working model. However, if the boom can not swing, how do you propose to travel with the unit in a train. Part of the reason for swing is so that the boom will stay in place on the tender. If it didn’t swing then it would have to be supported by the lines that raise and lower it above the deck of the tender and then would in effect be swinging back and forth on every curve. This would make the thing a nightmare to move.
On my model, I have moved it in a regular train and have not had to reduce speed because of the derrick, but I did try moving it with the tender set aside and pushing the derrick as would have been done when using it, and had to go very slowly because the boom would begin to sway and tip the derrick over. I’m sure this was an issue on the real one as well.
Any way, not meaning to start an argument here, build it as you like. I’ll still bring mine down in May so you can examine it.

#18

Ron, You are correct. Back to more research in Chama, with pics of the pivot beam, said it pivoted 30 degrees right and left. I have a video of the actual prototype unit in a train. I’ll have to re-watch it to see how it handles the curves. But even with my 18’ dia curves, they are still tight compared to the real thing. Interesting you brought this up. Now I’ll have to make it swing so it will go around my curves without hanging the boom end way out over the idler car. That fact completely skipped my feeble mind. One thing after another…:slight_smile: :slight_smile: I ain’t building this to set on a siding. I’d like to move it around the layout. Are there any other unforeseen prollems I might run into? Maybe I should just buy one of these already built. :slight_smile: :slight_smile:

(http://freightsheds.largescalecentral.com/users/jebouck/image25191.jpg)

#19

Hey John,

“The boys down at Chama wrote (on their forum) the boom was fixed and it ran with compressed air from the locomotive.”

I think they may have been writing about OB, rather than OP…
To run a model OP around in consist, you will need to make the boom pivot - or have some seriously wide curves!

(Oh - and if you can get an OX, by all means - they are LOVELY models!!)

Josh

#20

The more I look at pictures and plans, the more confused I get!
Plans and pics of the idler car show a rack that supports the boom, with big “L” brackets that the boom rests between. These would make it impossible for the boom to move from side to side while riding on the idler.
Also, two twisted flat bars, about 6-8" wide fasten at the top of the A frame and thence to the sides of the boom. These again would make the boom very hard to pivot. They may allow a little play, but not much.
And running from the top and down the back of the house is an air line with a standard glad hand. Also there isn’t any steam exhaust stack or anything like that to show it was run by steam.
Very frikken confusing.