Minimum HO Curve Radius

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J.Albert

Member
I dunno, Hal.

I think you'd do better keeping the Master for yourself, and putting the railroad in the second bedroom. The floor plan and doors look like they'd be easier to deal with.
 

Brakeman Hal

Well-Known Member
J. Albert- I agree excerpt for one detail: The Master bedroom leads directly to the Master Bathroom, which has a Tub, not a Shower. I never use a bathtub, only the shower.

In the 23 years we lived in our present home, I never used the bathtub ONCE.

To take a shower, I would have to go from the Master bedroom to the 2nd bedroom, which connects to the bathroom which has a nice enclosed shower, with safety rails.

This is why I'm choosing the bedroom with the connected Shower!

BUT WAIT A MINUTE.....

As I now recall, the master bathroom's tub has an overhead shower on one end, and a long rod running the length of the enclosure which can be fitted with a Shower Curtain!

THIS CHANGES EVERYTHING!

Hal
 
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wizz-bang

New Member
Hal, I have just a few comments.

(1) just finished installing two, one-eighty-degree 18" radius curves on my layout, and one of them has a significant issue at the join between two pieces of flex track. It's REALLY hard to get a good smooth curve through a flex track join, and especially hard at 18".

(2) For that reason, I would seriously think about using Kato Unitrack for those long (180 degree) curves: flex track will require a join right in the middle. You can easily transition from Unitrack to flextrack (I think Kato even sells a transition piece.) This will insure trouble free operation through those long curves.

(3) If you decide to go with flex track, solder the joins before you curve the track and before you lay the curve. I don't know if this will solve the problem I had, but it sure can't make it worse. The earlier comment about ribbonrail is spot on. I personally prefer Atlas code 83 flex track: I think it flexes more smoothly.

(4) Your 22" radius plus 1.5" to the edge of the right-of-way means your trains will be running VERY close to the edge of a 48" sheet. You'll have no room for scenery and nothing to catch equipment in the event of a derailment. Add to that the long reach issues, which I think you may be underestimating. I'm 6'-2" and it was about all I could do to reach the back of my 32" wide layout. It's one thing to reach four feet across a flat table; it's another thing entirely to reach across a 4 foot layout with trees, structures, scenery, etc. (By the way, I have a BLI 2-8-2, a Genesis 4-6-6-4, and a Proto 2000 2-8-8-2. All track nicely around the 18" radius - except at those pesky rail joins! - although the articulated locomotives look a little stupid hanging off the centers of the 18" curves. (I plan one day - when I get management approval for my next expansion - to replace those 18" radius curves with 24".

(5) Last (and this is just my personal experience and may be entirely out of date), I have in the past bought two Bachmann DCC locomotives, and neither one has ever performed acceptably. No low speed performance at all; high speed performance is not at all smooth or consistent. This experience is years old and may no longer be relevant.

Good luck!
 

Iron Horseman

Well-Known Member
(3) If you decide to go with flex track, solder the joins before you curve the track and before you lay the curve. ..., but it sure can't make it worse.
Yes, it can. I know many people use this technique successfully, but I disagree it can't be worse. Soldering in advance means one of those rails has to slide a lot further than the other requiring one to remove many more ties than letting the rails offset and soldering in place. In the area where the ties get removed, one has to be very careful to not let the gauge get too narrow there. Offset joints have the opposite rail to help hold them kink free and in gauge.

However, I do recommend sectional track for 18" curves. One gets the nice 20th century clicky clack of the railroad track and none of the hassles of making flex track go around tight corners.
 

wizz-bang

New Member
Yes, it can. I know many people use this technique successfully, but I disagree it can't be worse. Soldering in advance means one of those rails has to slide a lot further than the other requiring one to remove many more ties than letting the rails offset and soldering in place. In the area where the ties get removed, one has to be very careful to not let the gauge get too narrow there. Offset joints have the opposite rail to help hold them kink free and in gauge.

However, I do recommend sectional track for 18" curves. One gets the nice 20th century clicky clack of the railroad track and none of the hassles of making flex track go around tight corners.
Great tips - thanks. If I were to solder that joint (which I won;t based on your advice) I'd slide the rails away from the joint, cutting at both ends. I nearly went with sectional track, but I wanted to create a transition curve at either end. Looking back, I could have used about 120 degrees of sectional track and created the transitions using flex track. Would that have been better? No idea.
 

Brakeman Hal

Well-Known Member
I always form my flex track curves, (complete with transitions), before joining the sections. Then I cut the rails to match and then slip on rail joiners, then solder the joints.


Hup Hup Hup!
 

wizz-bang

New Member
Well, I may have gotten myself wrapped around the axle when I did this project. As I said, I chose Atlas because it flexes more easily. What it does NOT do, however, is hold its shape once you've gotten the curve you desire - it just springs back to straight. In retrospect, based on your comment and on Mr. Horseman's comments, perhaps I should've used Peco or Micro Engineering instead, and worked the curves until they were perfect.

So, I haven't ballasted yet; the track is temporarily held in place with track nails. Maybe I need to tear it out and redo?

(Sorry, Hal, I've gotten way off the original point of this thread!)
 

Selector

Well-Known Member
Follow these steps, in order, to fashion any curve radius with HO flex track, except below about 16" radius is becomes very difficult:

a. Take your lengths, with one length's sliding rail slid further back into itself. Withdraw the sliding rail at least six full ties. Curve that length until it matches your radius, and nail it down with track nails;

b. Make the other length's sliding rail extend in the same direction and insert it fully into the tiny spikehead details until it abuts the withdrawn sliding rail in the first length. Then curve that length the same way and spike it down;

c. Where they abut, mark and remove two ties under that abutment, both rails. Remove the second length, insert a joiner in the tie gap, and then mate the two lengths once again, sliding the second slider rail into the spikehead details, and then run it up to the joiner and insert it. Reform that curve and spike;

d. Solder both joiners, the non-sliding rail joiner and the sliding rail joiner. Take the soldered length, track nails removed, and lay it along your centerline. Spike it into place and join it to other rails, and leave the spikes in place until hardened ballast retains it in place.
 

Iron Horseman

Well-Known Member
Well, I may have gotten myself wrapped around the axle when I did this project. As I said, I chose Atlas because it flexes more easily. What it does NOT do, however, is hold its shape once you've gotten the curve you desire - it just springs back to straight. In retrospect, based on your comment and on Mr. Horseman's comments, perhaps I should've used Peco or Micro Engineering instead, and worked the curves until they were perfect.
Peco is also springy.

I use adhesive for holding the track in place and bulletin board stick pins to hold the rail in the curve I want. Glue down on the roadbed. Connect the one end of the track, ties into the glue. Make a "gross" curve and lower the track into the glue. Pin it in a few spots to keep it from springing. Go back and refine the curve with a few more pins. Go back to the connection and get the real curve and pin into place. Wait for glue to dry.
 

Iron Horseman

Well-Known Member
Looking back, I could have used about 120 degrees of sectional track and created the transitions using flex track. Would that have been better? No idea.
I have no idea either. There usually isn't really a "better", just different. On one layout I did, I used one piece of 22" sectional leading into the 18" as a transition.
 




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