How should I support a double-deck peninsula?
Here's what I'd like to accomplish:
I've looked at every image that comes up with a google of "model railroad benchwork" without finding an example of what I need, but I know it's been done. I'm not afraid of an engineering challenge, but then I'm not into re-inventing the wheel either.
Thanks!
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
Looks like you are talking HO?
I assume you want to travel a grade from one deck to the other. How large is your room and what are the obsticles you have to deal with: door, windows, closets, posts, apliances?
When you say unobstructed "depth on lower deck" do you plan to have a view block between the two sides or will it be open?
What is your anticipated maximum height above the floor you are thinking of for the upper deck?
Extruded foam for a layout base might be lighter on the second deck.
Could you post a track plan (I don't know how to) or better description of your plan?
What comes to mind is a post with two cross arms. As long as there is a divider on the lower deck, hiding the upper deck bracing shouldn't be too hard, if it is open you'll need to be a little more creative. I have seen well disguised posts using buildings and sky coloring along with a busy area to draw attention away from the support.
Afraid this isn't much help, but the answers may help others help you.
Good luck,
Richard
My current layout incorporates a double deck peninsula running along the center of my garage. The benchwork consists of open grid framing double-cantilevered off of a central stud wall. I bought several kiln dried 2 by 4's and let them sit for several weeks to ensure that any warping would occur prior to beginning work. I then carefully ripped these 2 by 4's down to 3" inches wide taking only about 1/8" at a pass and using a four foot long rip fence to get them as straight as possible. I then erected a wood frame wall with the studs at 16" on center along the center of the garage. I glued the bottom plate to the garage floor using Liquid Nails Construction Adhesive and screwed the top plate to the underside of existing storage loft joists. I next cut all of the open grid framing members from sheets of 1/2" hardwood plywood. Forty-seven inch long ribs were centered on the wall studs at each level and glued and screwed to the studs. Structural fascia strips were cut from the plywood and attached to the ends of the ribs using glue, glue blocks and wire brads. As the one end of the peninsula is round, I laminated strips of 3/16" plywood to create the curved structural fascia around the end. Finally, I added grid members parallel to the fascia and halfway between the fascia and the stud wall to reduce the size of the open grid squares. The result is a peninsula about 13 feet long, 4 feet wide and with each deck at least 22" deep.
Since the locale I'm modeling is relatively flat, I next glued 3/16" plywood to the top of the open grid framing although I don't see why foam insulation panels and/or spline roadbed couldn't be substituted. I then glued 1/4" drywall panels to the stud wall for additional shear strength and to double as backdrop down the center of the penisula. The glued framing joints combined with the vertical and horizontal shear strength of the plywood decks and drywall backdrops make this structure surprisingly strong and rigid. It will easily hold my weight (200 lbs) while I lean on the decks to install track, roads and scenery. Best of all is the large amount of storage under the lower deck as there is uninterrupted space 22" deep around the entire peninsula.
Hornblower
Hi Richard,
Yes, HO.
I plan on a backdrop, as narrow as possible, down the center of the peninsula. I've had to squeeze down the shelves on the opposide sides of the aisle from the peninsula so things will fit making this the only area where I can have any real depth to the scenery so I'd like to preserve as much of it as possible.
The two decks are 40" and 56" from the floor. There is a reversing loop under the lower deck at 32".
I'm climbing between the two decks with a continuous grade that goes twice around the lower deck, but only once around the peninsula.
Foam is out since it's not compatible with my spline subroadbed. The track constantly climbs between 1.5% and 1.8% east to west from the start on the lower level to the yard that is at the summit. The yard is the only level track on the layout (except for a few spurs for coal loaders). I believe this requires grid and riser construction.
The track plan for the peninsula is a simple single track out and back turnaround blob.
The post with two crossarms is good for the sides of the penisula. What I'm trying to figure out is how to handle the end. I should have pointer that out in the OP.
Thanks for your interest.
Two Information Station (PDFs) are worth the effort:
Guide to helix staging and design (Vol. 1)
Guide to helix staging and design (Vol. 2)
The pictures are descriptive -- The articles are even more descriptive.
Also, look at Brunton's, The Behemoth Helix -- From his CB&Q New Jersey Layout before his recent move to South Carolina.
Conemaugh Road & Traction circa 1956
Very cool Hornblower - so you used the fascia as a structural element. Excellent idea! I hadn't thought of that.
How tall are your ribs?
Got any pictures of the end of your peninsula?
carl425 Very cool Hornblower - so you used the fascia as a structural element. Excellent idea! I hadn't thought of that. How tall are your ribs? Got any pictures of the end of your peninsula?
I agree, excellent construction method. One forum member has used this for a considerable sized basement layout where the center wall was 2x6 under the girder/ lally colum. Don't remember off hand who, but they also have quite the fantastic helix that has been posted numerous times. Hope they can post pics as well.
Did you run the end radius joists in a "radian"? a
Modeling B&O- Chessie Bob K. www.ssmrc.org
Build a stud wall
Sorry to all for not replying sooner. I guess I just never went back to this thread since I first posted to it. Anyway, the cantilevered ribs are five inches deep at the center stud wall tapering up to three inches deep where they meet the structural fascia. The fascia is four inches deep which gives me a shallow valance for hiding wiring and lighting. The top surface to top surface deck separation is 18 inches resulting in a clear veiwing height of 14 inches between decks. I'll have to see if I can provide some pictures but its been so long since I've posted any, I don't know if I remember how (or even my account name at Photobucket for that matter).
The radiussed portions of the fascia were fabricated by soaking 4" wide strips of 3/16" plywood in water then placing the ends of the plywood strips between some of the wall studs to hold them in a curved shape. The strips were soaked again the next day and again set between the wall studs to force a tighter radius. Peninsula end ribs attached parallel to the stud wall as well as at 45 degree angles were trimmed to length along the desired radius. A radius template was cut from a large piece of cardboard and placed atop the end ribs. The first layer of curved plywood was then glued and pinned to the end ribs using 18 gauge wire brads, carefully adjusting each attachment point to maintain alignment with the edge of the radius template. The ends of the curved plywood were carefully trimmed to butt against the ends of the straight fascia pieces with additional pieces of 1/2" plywood glued and pinned behind these butt joints. Once the glue on the first layer had cured, the second layer was laminated to the first and held in place using wire brads and lots of spring clamps. The third and final layer was attached in a manner similar to the second layer. The resulting curved fascia pieces were about 1/16" thicker than the remainder of the 1/2" plywood fascia strips but a little sanding was all that was needed to cure that.
Okay, I took a few photos of my peninsula framing. Now if I can only remember how to post them.
This first shot is a view of the north side of the peninsula showing the length of the peninsula and both decks. This shot also shows how much storage room is available under the layout and just how far my fascia spans without additional supports.
The next photo shows the central stud wall where it meets the lower deck framing. This view shows how the cantilevered ribs were attached to each stud, the taper of each rib from the central stud wall out to the structural fascia, plus the fascia. The next photo shows the underside of the lower deck at the radiussed end of the peninsula. You can see the three layers of thin plywood laminated together to form the curved fascia. Also visible are the end ribs and the shallow ribs at 45 degrees. The next photo shows the south side of the peninsula upper deck framing with LED puck lights, DCC bus and feeder wires. The framing is exactly the same as for the lower deck. The last photo shows the north side of the peninsula upper deck framing. The biggest issue I had with framing out this peninsula was the need to keep almost half of the area above the central stud wall open to clear my sectional-style garage door. This means that the first tie-in of the top of the peninsula framing to the existing garage framing is a good five feet in from the end of the peninsula. The bare framing did flex a little because of this. Fortunately, glueing the 1/4" drywall panels to the center studs created enough sheer strength in the structure to eliminate all but the slightest flex. As I said before, this very lightweight structure holds my 200 lbs. quite easily although I certainly wouldn't attempt to dance on it! Scenery on my layout is only about 15% finished. About 90% of the track is laid (staging and turntables still to be finished). I also have about 75% of my roads constructed. I started this layout about three years ago so it should continue to keep me busy for at least another 15 years or so.
The next photo shows the central stud wall where it meets the lower deck framing. This view shows how the cantilevered ribs were attached to each stud, the taper of each rib from the central stud wall out to the structural fascia, plus the fascia.
The next photo shows the underside of the lower deck at the radiussed end of the peninsula. You can see the three layers of thin plywood laminated together to form the curved fascia. Also visible are the end ribs and the shallow ribs at 45 degrees. The next photo shows the south side of the peninsula upper deck framing with LED puck lights, DCC bus and feeder wires. The framing is exactly the same as for the lower deck. The last photo shows the north side of the peninsula upper deck framing. The biggest issue I had with framing out this peninsula was the need to keep almost half of the area above the central stud wall open to clear my sectional-style garage door. This means that the first tie-in of the top of the peninsula framing to the existing garage framing is a good five feet in from the end of the peninsula. The bare framing did flex a little because of this. Fortunately, glueing the 1/4" drywall panels to the center studs created enough sheer strength in the structure to eliminate all but the slightest flex. As I said before, this very lightweight structure holds my 200 lbs. quite easily although I certainly wouldn't attempt to dance on it! Scenery on my layout is only about 15% finished. About 90% of the track is laid (staging and turntables still to be finished). I also have about 75% of my roads constructed. I started this layout about three years ago so it should continue to keep me busy for at least another 15 years or so.
The next photo shows the underside of the lower deck at the radiussed end of the peninsula. You can see the three layers of thin plywood laminated together to form the curved fascia. Also visible are the end ribs and the shallow ribs at 45 degrees.
The next photo shows the south side of the peninsula upper deck framing with LED puck lights, DCC bus and feeder wires. The framing is exactly the same as for the lower deck. The last photo shows the north side of the peninsula upper deck framing. The biggest issue I had with framing out this peninsula was the need to keep almost half of the area above the central stud wall open to clear my sectional-style garage door. This means that the first tie-in of the top of the peninsula framing to the existing garage framing is a good five feet in from the end of the peninsula. The bare framing did flex a little because of this. Fortunately, glueing the 1/4" drywall panels to the center studs created enough sheer strength in the structure to eliminate all but the slightest flex. As I said before, this very lightweight structure holds my 200 lbs. quite easily although I certainly wouldn't attempt to dance on it! Scenery on my layout is only about 15% finished. About 90% of the track is laid (staging and turntables still to be finished). I also have about 75% of my roads constructed. I started this layout about three years ago so it should continue to keep me busy for at least another 15 years or so.
The next photo shows the south side of the peninsula upper deck framing with LED puck lights, DCC bus and feeder wires. The framing is exactly the same as for the lower deck.
The last photo shows the north side of the peninsula upper deck framing. The biggest issue I had with framing out this peninsula was the need to keep almost half of the area above the central stud wall open to clear my sectional-style garage door. This means that the first tie-in of the top of the peninsula framing to the existing garage framing is a good five feet in from the end of the peninsula. The bare framing did flex a little because of this. Fortunately, glueing the 1/4" drywall panels to the center studs created enough sheer strength in the structure to eliminate all but the slightest flex. As I said before, this very lightweight structure holds my 200 lbs. quite easily although I certainly wouldn't attempt to dance on it! Scenery on my layout is only about 15% finished. About 90% of the track is laid (staging and turntables still to be finished). I also have about 75% of my roads constructed. I started this layout about three years ago so it should continue to keep me busy for at least another 15 years or so.
The last photo shows the north side of the peninsula upper deck framing.
The biggest issue I had with framing out this peninsula was the need to keep almost half of the area above the central stud wall open to clear my sectional-style garage door. This means that the first tie-in of the top of the peninsula framing to the existing garage framing is a good five feet in from the end of the peninsula. The bare framing did flex a little because of this. Fortunately, glueing the 1/4" drywall panels to the center studs created enough sheer strength in the structure to eliminate all but the slightest flex. As I said before, this very lightweight structure holds my 200 lbs. quite easily although I certainly wouldn't attempt to dance on it! Scenery on my layout is only about 15% finished. About 90% of the track is laid (staging and turntables still to be finished). I also have about 75% of my roads constructed. I started this layout about three years ago so it should continue to keep me busy for at least another 15 years or so.
The biggest issue I had with framing out this peninsula was the need to keep almost half of the area above the central stud wall open to clear my sectional-style garage door. This means that the first tie-in of the top of the peninsula framing to the existing garage framing is a good five feet in from the end of the peninsula. The bare framing did flex a little because of this. Fortunately, glueing the 1/4" drywall panels to the center studs created enough sheer strength in the structure to eliminate all but the slightest flex. As I said before, this very lightweight structure holds my 200 lbs. quite easily although I certainly wouldn't attempt to dance on it!
Scenery on my layout is only about 15% finished. About 90% of the track is laid (staging and turntables still to be finished). I also have about 75% of my roads constructed. I started this layout about three years ago so it should continue to keep me busy for at least another 15 years or so.
Very nice, Hornblower. I'm curious to know what elevations you established for your lower and uppper levels. Also your height and the heights of the others who might be running the railroad. Thanks.
Thanks ACY. I used the old "armpit height" rule for the upper deck. This put the upper deck at 52 inches above the floor. I wanted good visual and physical access to the lower deck so I set the lower deck height at 34 inches. With the 4 inch depth of the upper deck fascia, this leaves 14 inches of clearance between the upper and lower decks. This also leaves 30 inches of clearance between the floor and the bottom of the lower deck fascia. I use an old secretary's chair on casters when working on the lower deck or on the upper deck wiring. I placed an automotive creeper atop the red wagon visible in the photos to perform the lower deck wiring. This allowed me to lay underneath the layout at a comfortable height plus allowed me to wheel myself along the length of the layout as I worked. The upper deck is a little high for younger operators to see well without a step-stool but the wide aisles and trackwork close to the near edges of the layout means they can still see the trains if they take a few steps back. The lower deck is perfect for the little ones. I've had kids as young as 5 years old running trains around the layout and they all seem to thoroughly enjoy it.
The layout is based on a little known fallen flag named the Santa Ana & Newport Railroad built and operated in the early 1890's. Although the prototype was absorbed into the Southern Pacific by the turn of the twentieth century, my layout assumes that the line remained independent and operating into the late 1950's. The prototype enjoyed a good working relationship with the Santa Fe. In fact, the owners of the SA&N wanted to sell the line to the Santa Fe. Unfortunately, the deal was not completed because the Santa Fe was working it's way out of a recent bankruptcy. Instead, the line was sold to the owners of a local sugar beet plant who were in turn bullied into selling the line to the Southern Pacific. Extensions of the original SA&N trackage to the Southern Pacific's main line created a prototypical loop of track around the north half of Orange County, California. My layout scenario assumes that the still independent SA&N maintained its relationship with the Santa Fe (even using retired Santa Fe small steam for motive power) but also made a deal with the Southern Pacific to share a new yard and track rights that included a consolidation of the parallel SA&N and Pacific Electric tracks into a single line between Newport Beach and Huntington Beach. This scenario allows me to feature SA&N and Santa Fe operations while also including more limited operations by the Southern Pacific and the Pacific Electric (no more "Red Car" service and all dieselized in the area by the 1950's). The small size of the 1890's locos and rolling stock meant that curves on the SA&N were relatively tight. The rapid growth that occurred in Orange County meant that space was no longer available to broaden curves to accomodate more modern equipment. Thus, my layout assumes that 1950's operations are still limited to mainly 40' freight cars, small steam, and four axle diesels. This allows me to use 22" radius curves to pack in as much layout as possible in a 10' by 19' space. The layout uses a 22" radius helix at each end of the layout to complete the "prototypical" loop. Fortunately, the short trains allowed on the SA&N trackage (about 10 cars max) negotiate these "tight" helixes just fine. I still need to complete the engine servicing areas of the two main yards as well as three planned staging areas so this layout should keep me busy for some time.
Hi Hornblower,
A 22" radius helix works fine, huh? I got some very authoritative advice here a couple months ago that anything less than 30" was ill advised and that for anything less than 26" to work would require the repeal of the laws of physics.
What's the weight of those 10 cars and what do you pull them up the helix with? It's just a curiosity for me now as I reworked my plan into a "nolix" configuration based on the advice I got earlier.
Also, a real question, what radius were you able to bend that 3/8" pltwood to? I'd need to get down to about 26"
Like Carl, I was wondering about the tight radius of the helix; but we do what we have to do with the space available. I would predict problems with long trains, or with any cars longer than 40', or any engines larger than a 2-8-0. Passenger trains could present problems, too. Hopefully this won't be a problem. I'm asking because I have to make some decisions regarding the design of my "retirement project" railroad. Lots to consider, and not many easy answers.
I'm using a 2.5 turn 22 inch radius helix on my HO branch line with no problems. This is a coal branch using 2-8-0, 2-6-6-2, GP-7 and GP-9 as motive power. Train length is modest (max 12 cars) and single passenger car is planned (62 feet), freight cars are 40 ft or less. Train speed is max 15 mph uphill and 10 mph downhill. Would I use this on a mainline run - no, the typical mainline motive power and equipment requires much larger radii than this. But if you are careful both in the building phases and using this tight radii appropriately it can work.
Charles
Being space constrained, I was forced to build each helix (2) with the small 22" diameter. Each has 4.5 turns and a grade of 2.6 percent (uncompensated). I find that a single Athearn blue box four axle diesel can easily haul a 10-car train of 40' freight cars, all weighted to NMRA standards, up this grade. Two Athearn four axle diesels in consist have hauled an 18 car train. My two steamers pull the "Merry-Go-Round" mixed trains (what the SP nicknamed its mixed trains that ran around the old loop until the 1930's). These mixed trains consist of an MDC 2-6-2 Santa Fe style Prarie loco pulling a single 40' boxcar and two 50' wooden passenger cars (again, weighted to NMRA standards). These little locos can pull these mixed trains up each helix without drama although adding a second boxcar can cause a bit of slipping. While these are indeed short trains, my passing sidings can't handle much more than ten car trains anyway.
I was eventually able to bend three layers of 3/16" plywood into a 24" radius. This took soaking each piece of plywood in water for most of a day, then carefully bending it into a radius of around 36" and letting the plywood dry out again overnight. A second day of soaking and another night of drying out set in a radius near 24" got me very close. The final bend (very little by this point) was made while attaching and laminating the layers to the layout benchwork. I was fortunate that only one piece of six broke (during the second bend)! Fortunately, the seventh piece took the curve nicely.