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+--- Thread: new project (/showthread.php?tid=370)
Re: new project - ocalicreek - 08-01-2011
For a first try it's really pretty good.
I've got a box of supertrees - the starter kit - that I've had for years now. I bought it and we moved, and each time layout construction reaches that point where I could break out the tree kit we move or something else gets in the way. This time I will make trees for the current bonus room layout! No promises on a timeline, but I will make the trees!
Looking forward to more progress.
Galen
new project - e-paw - 08-17-2011
I resumed work on the bridge (DH draw) yesterday. I started adding the bottom to the bridge. My first idea was to use brass stock for the decking for strength, but after my load test ( up to 6 pounds ) I realised that It's not necessary and would just add extra weight. So I went back to the Central Vally girders that the rest of the structure is built from. To insure a good glue bond, I sanded some of the primmer away where the new parts met the old ones.
In this one I have started on the tower section that will cross over the PRR trackage.
Re: new project - tetters - 08-18-2011
That is going to look amazing with some double track and a train moving through it. Your efforts are going to pay off big time when you finish this build and install it on your layout.
Re: new project - Green_Elite_Cab - 08-19-2011
That is probably one of the coolest model bridges i've ever seen.
new project - e-paw - 09-09-2011
Thanks for the comments everyone. I have completed a little more work to the bridge, so DH draw is now back in an active build state again.
First off, I measured, measured, and remeasured where my tracks were going to be located and then measured yet once again, (just to be sure). Once I was satisfied with the location of the mains I drew them out on the Foam board that I had used earlier. This gives me a good visual reference to where they are in relation to the center line of the bridge, In this case, the lift section.With a few pins I tacked down the movable section to the board and added girders to support the ties and track.
Each one was carefully cut, filed and glued in with CA to insure the tightest fit possible.( I really want to avoid having A heavy mike or train master splashing down into the river.
While that dries I went to work on the track...In general, the track that crosses bridges has a closer tie spacing than other track. My solution was to flip the track over and cut out the tabs between the ties on some flex track and slide them closer together. This pic shows the finished product compared to a standard section of track.
With that finished, the track was centered and secured to the bridge with more CA. Because this section will be movable I needed a way to get power to the rails. Feeders were soldered to the rails and then soldered to brass shims glued to the under side of the bridge with,,, yet more CA. When the bridge is in the closed position they will make contact with some other live contacts to complete the circuit. This was done at both ends to insure good power to the lift section.
new project - e-paw - 09-10-2011
As I said before the thought of some locomotive crashing into the river below is something that I want to avoid. To add a little bit of extra insurance I added some extra bracing to the bottom of the bridge. The joints where the frame meets the sides of the bridge are the weakest link in the build. In order to add some strength here I cleaned off the primmer to allow for a solid bond and glued a strip of plastic across the seam using a strong solvent cement. Each seam got the same treatment.
My next step was to add the center guard rails found on all bridges. In the real world ,as in our miniature one, these rails help to keep a train under control in case of a derailment.
new project - e-paw - 09-10-2011
The last detail that I wanted to add to the underside of the bridge was some thinner cross bracing. I used this image of the CNJ's Newark Bay Drawbridge as a guide.<!-- m --><a class="postlink" href="http://lcweb2.loc.gov/cgi-bin/displayPhoto.pl?path=/pnp/habshaer/nj/nj0800/nj0876/photos&topImages=112212pr.jpg&topLinks=112212pv.jpg,112212pu.tif&title=10.%20%20DETAIL%20VIEW%20OF%20FLOOR%20SYSTEM%20FOR%20210'%209'%20LIFT%20SPAN%20%3cbr%3eHAER%20NJ,7-NEARK,16-10&displayProfile=0">http://lcweb2.loc.gov/cgi-bin/displayPh ... yProfile=0</a><!-- m --> I didn't want to put too much detail into it as it can only be seen when the bridge is raised, and even then, it's still not too visible.
after that I started on the counter weights. Once again I went to the library of congress web page for Ideas. I used the same prototype for inspiration, <!-- m --><a class="postlink" href="http://lcweb2.loc.gov/cgi-bin/displayPhoto.pl?path=/pnp/habshaer/nj/nj0800/nj0876/photos&topImages=112217pr.jpg&topLinks=112217pv.jpg,112217pu.tif&title=15.%20%20DETAIL%20VIEW%20OF%20MAIN%20AND%20AUXILIARY%20COUNTERWEIGHTS%20FOR%20299'%20LIFT%20SPANS%20%3cbr%3eHAER%20NJ,7-NEARK,16-15&displayProfile=0">http://lcweb2.loc.gov/cgi-bin/displayPh ... yProfile=0</a><!-- m --> I did change the look a little but you can still see the similarities.
Here is the almost finished product of one of the main counterweights. I added the small aluminum blocks on the left to the inside of the weights. This added some heft to the otherwise light box. I felt it would help to keep the "wire rope" stretched when they're installed.
Re: new project - Herc Driver - 09-10-2011
Very nice work!
new project - e-paw - 09-15-2011
Thanks mark.
Re: new project - Green_Elite_Cab - 09-15-2011
Are your supports H columns and I-beams? If you really want it to be secure, it might not hurt to drill small holes in and feed in steel wire in hidden or inconspicuous places. That way, you have a physical support, and you're not relying on a glue joint alone. I try to do this where ever straight glue is not enough.
new project - e-paw - 09-17-2011
Well GEC the girders are of a " BOX " type.
![[Image: 055.jpg]](http://i840.photobucket.com/albums/zz328/gronku2/the%20gauge/055.jpg)
Apparently they are light weight and strong, just like the prototype.I did my final load test today. I supported the lift section from the ends, just like it will be when installed. To simulate a good load I piled as many of my heaviest loco on the rails as I could fit.
![[Image: 051.jpg]](http://i840.photobucket.com/albums/zz328/gronku2/the%20gauge/051.jpg)
![[Image: 053.jpg]](http://i840.photobucket.com/albums/zz328/gronku2/the%20gauge/053.jpg)
![[Image: 052.jpg]](http://i840.photobucket.com/albums/zz328/gronku2/the%20gauge/052.jpg)
![[Image: 054.jpg]](http://i840.photobucket.com/albums/zz328/gronku2/the%20gauge/054.jpg)
The grand total came to ..........9 pounds, 3.6 ounces. I'm no longer worried about the load carrying capacity of the bridge..
Re: new project - tetters - 09-17-2011
Bravo! Nicely done sir! This is going to look incredible.
Re: new project - Ralph - 09-17-2011
WOW!!!
Ralph
Re: new project - Steamtrains - 09-17-2011
E-paw....Do a flex test by placing your heaviest loco right at the center of the span and measure the distance from the bottom of the girders to your base at this point. Compare this measurement to the distance with no load on the bridge measured at the same point. Even a small deflection can cause electrical pick-up problems...
It sure is turning out to be a terrific addition to your layout...
Re: new project - toptrain - 09-18-2011
steve ; Do you remember us running 2 Penn-Line decapods doubleheaded on the basement elevated track and the way that track would flex. That put a load limit on the upper lines. I never did strengthen that section.
* Something you will recognize. A ANNA Mountain fully detailed on the elevated lines, with a Bowser Mountain on the second track.
frank