Removing acrylic caulking from cork roadbed
#16
Woah! Unbelievable. I would love to know the actual reason why that happened. Stuff like that scares me - what's to stop that from happening on everyone else's layout? If we knew the actual culprit, we wouod be armed with the knowledge to minimize the chances.

I shouldn't worry about my layout though. It went through 70 degree F temp changes from summer to winter, and also saw a variety of humidities for a four year period when it was in the garage. No problems. Perhaps the 2" foam contact cemented to the benchwork is a stabilizing platform for the layout. Again, the layout went through some drastic temp and humidity changes without a single issue.

I feel for you Johnny. I know I would be bummed out if that happened to me. Thanks for the photos. I'm still amazed that something like that can happen.
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#17
What is even weirder is why didn't the track next to it experience the same thing? One track buckled, the parallel track didn't? What is different between the two tracks?
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#18
You should be fine witht he foam. My previous layout was in an unfinished basement and in summer it was a struggle even with a dehumidifier to keep it dry enough, in winter it was plenty dry but hard to heat as there were only a couple of small space heaters. Never had a lick of trouble with anything shifting or buckling. The extruded foam is quite dimensionally stable. The previous owners of the house left behind 2 gallons of black interior paint (what they had intended to paint black INSIDE the house, I have no idea) so after I built the wood frames to hold the foam, I painted all the exposed surfaces, ust one quick coat so it certainly wasn't sealing the wood, but it may have helped, plus it was a flat finish so it hid the legs. I never had a problem with expansion or contraction of the wood pullign the foam loose, either. Frames were basic box frames of 1x4's, the foam was glued to the narrow edges of the 1x4's with yellow glue. I even managed to bash my head against the foam from underneath more than once and STILL it never popped loose.
This experience prompted me to stick with the same basic techniques for my current layout, even though it is in a more regulated spare bedroom environment (I have heat and AC!).

--Randy
Modeling the Reading Railroad of the 1950's in HO

Visit my web site to see layout progress and other information:
http://www.readingeastpenn.com
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#19
I've had a similar experience actually. I finished hand laying a good four foot section of double track on my first layout but apparently didn't gap the rails enough. Once the furnace kicked during the winter that particular section of track went all out of whack, bent and buckled. It was ridiculous. The rail ends pushed so hard on adjoining track that it actually closed some isolation gaps in a turnout that I cut with a dremel disc! It was almost surreal. Granted I'm spiking rail to wood ties and you have flex track. However I can say with some certainty that the rail does expand and it can expand enough to throw it all to heck. I did take pictures, but cannot seem to locate them...if I find them I'll definately post them up just to make a point.

My solution to the problem was kind of simple in a way and for all intents and purposes it seems to have worked, or at least, there is no buckling this time around. For starters, I capped off the vent for air coming into the room. The vent would blow hot air right onto the layout and make the whole area very warm. The layout sits just a few feet away from the furnace but the furnace itself does not radiate a lot of heat all the heat from the forced air is sent through the ducts to the rest of the house. Which is how it should be. Closing off the vent allows the layout area to remain at a more stable (cooler) and consistent tempurature. For layout # 2 I also did all if not most of the track work during the winter months, when the house actually is at its warmest. Call me paranoid. When the basement is cooler in the summer months I don't notice any significant "shrinkage" and when the house is warmed during the winter there is no noticable change in expansion. For gaping, I just stuck a business card inbetween joints and left it there while I spiked. Maybe I over thought this, but so far so good.

Just wonder if seasonal changes and room tempuratures might have impacted this in some way? I also wonder if perhaps certain stock or batch of Nickel Silver Rail are more susceptable to this type of event?
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#20
Thanks for the info, tetters. I sure would like to see those photos if you dig them up.

As for different batches of rail having different expansion properties, I think the difference would be close to nil. There isn't much difference in the expansion rates of variouos types of brass alloys. The difference is in the 10 millionths of an inch if I remember the expansion chart correctly.

This track buckling has to be a combination of the wood benchwork shrinking due to drying out, and the expansion of the track due to the heat. I'm not worried a bit about my layout cosnidering its past performance in climate extremes, and now it has a comfy home in the layout building.
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#21
Gary S Wrote:Thanks for the info, tetters. I sure would like to see those photos if you dig them up.

As for different batches of rail having different expansion properties, I think the difference would be close to nil. There isn't much difference in the expansion rates of variouos types of brass alloys. The difference is in the 10 millionths of an inch if I remember the expansion chart correctly.

This track buckling has to be a combination of the wood benchwork shrinking due to drying out, and the expansion of the track due to the heat. I'm not worried a bit about my layout cosnidering its past performance in climate extremes, and now it has a comfy home in the layout building.

From my background around wooden boats, 99% of the problem is very likely the wood drying out and shrinking. Even a 4x8 sheet of plywood will change a 1/4" along its length given the right changes in humidity. Paint retards the flow of moisture in and out of wood, but does not stop the flow. The real value of paint is that it might slow the moisture flow enough to get past a spike or valley in ambient humidity. Leaving the heater on at a higher than normal temp dried the plywood and wood out more than normal, especially if it stayed that way for a few days.

Why did one track buckle and not the other? My guess is the gaps were slightly smaller on the track that buckled than on the other. It would have been an interesting experiment to turn on a humidifier while the temps were elevated (to avoid condensation), and see if the buckling went away.

The power of the expansion and contraction of wood is pretty incredible. Put a wood planked boat (freshly painted) in the water, and you can't believe how fast it is sinking from the water coming in. Pumps can't keep up. 3 days later, it won't leak a drop. OTOH, plank a boat with dry, seasoned wood without steaming the planking. Butt the planks together as hard as you can. Throw it in the water and see how fast the planks pop their fastenings.

just my thoughts and experiences
Fred W
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#22
An update to the problems I was having:
The the buckling track has been an ongoing problem, but to day while trying to correct it I have found the source of the trouble. I was following David Barrow's domino approach to building benchwork. I like the idea of nailing a laminate over the top of the plywood tabletop so the table could be reused if the track work ever needed to be changed. Well that laminate is the source of the trouble. I did not paint the underside of that laminate before a nailed it down. With the high heat and low humidity in the room over the winter, the laminate warped pulling itself away from the tabletop thus causing the buckling.

I'm happy I have found the source, but it looks like there will be some effort to fully correct the problem. So for the time being the Burbank branch will be under reconstruction. The track plan is solid and the operations are as I had envisioned, so the plan will stay the same. I will redo the tabletops using the plywood as the base, with no laminate, and relay the track work an hopefully be running again soon.

This is not a knock on Dave's domino idea, I still think it is a great asset, but in this particular application and installation it did not work. I think the main cause was not sealing the underside of the laminate and using too small of brads.

On to the rebuild!

John
John
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#23
I can't imaging that a change in temp. from 65 to 78 degrees would do a thing! Nope
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