How do you keep long straight aways... straight?

I don't worry about it, as I have looked at many of railroads and there not perfectly straight either. It may appear but if you look closely you will see there not. 

I use the edge of a long level up against the rails or ties. Hold the level with your thumbs and bring the outermost rails toward the level edge with your fingers. 

I align the edges of the ties with a 36-inch aluminum ruler, screw the track down, move the ruler 2-feet along the ties and do the next section of track.

MELGAR

I do as Romiller49 (and Melgar) does above, use a straight edge against the ties and/or rails. I use notched wooden blocks to keep the centers on curves and also check straight runs with them as well.

Someone recently posted some good pictures of a variety of these blocks, but I don't recall what thread it was? They are very handy to have around though. 

If a double main, blocks of wood the right length between so even if the lines are not square to the layout edge at least they will be in line.

Like Melgar and Rod,  I use straight edges, sometimes 4 foot level, sometimes aluminum rulers, sometimes a piece of quartersawn oak that I know is straight.   I find it helps me to make sure that I have located the center-line of track at both ends of the straight first, and then I will ensure that a couple of points in between are dead on that center-line.   

Almost all my track is on cork roadbed, so I make absolutely sure the center-line where the 2 halves of the cork are located is on that center-line, and I usually mark it about every 3 feet where it's verified to be dead center.   That way when I am pulling the track to the straight edge, I know I am not moving off my center-line.

If am putting down parallel straight sections, I usually get one done, then cut some wood spacer blocks to ensure the 2nd track stays equidistant from the first one down.  I will still employ the straight edge to check the 2nd one, but I like using the blocks to ensure distance between stays consistent.   

LASER

I use straight GarGraves track sections and just slap them down on my cork center line.  I do use a board to keep the spacing the same for the cork on parallel tracks.  I did some this past fall and I was able to sight down the straightaway with the eye after doing the above

Like Melgar, I use an aluminum straight edge, but a 48" one.  I've also used a laser.  Either one works great.  All of my tracks are flex track, though and I am in S.  When I was using classic Gilbert sectional track, the 48" straight edge worked great on the 10" straight sections.  Move it along overlapping the straight sections.  And like Mark, a true center line is the best start.

Stringline, 48” level, or 98” aluminum straightedge/saw guide.  

Same as Jim. I start off with a very tight string line that is 1/16" above the center rail. Then screw down two 30" straights only at their ends. Then add the rest of the screws to those two sections after clamping a 6' aluminum level against the ties or outside rails, in order to remove any bow that may be present in the individual 30" sections. I use mini 6" bar clamps from Harbor Freight. If you can control the temperature and humidity in your layout room, make sure you have it set at where you will be keeping it at all times, for a few days before laying long straight stretches. This will give your bench work time to adjust to your environment setting and help keep the straight-away straight when it's finished. As far as using lasers, I personally had bad experiences with them in the sawmill industry. To make a long story short, they lie to you and you don't have to look into them to go home with sore eyeballs at the end of the day.

I use a straight line laser tool. They are inexpensive and easy to use.

I used a 48” aluminum level against the rail plus eyeballing it. For longer tracks I used a string line. For parallel tracks I used a wood jig for 4 1/2” and 5” track spacing. 

Unfortunately I found that the straight rails on my Atlas #5 turnouts were not straight. They introduced a little jiggle in my yard. So I had to revert to the “prototype ain’t straight either” excuse. 

In my passenger yard I used Atlas 2-rail track that I added a code 100 center rail. This track is very flexible, so it was much harder to do long straight runs. I used the 48” level, but what I needed was someone eyeballing the track as I screwed it down. Didn’t have that option. Insert prototype excuse here.

Bob

I use an extruded piece of aluminum 4 1/2' long four inches wide about 1/2" thick on the edges. Also use a carpenters square for shorter straights. Even straight wood works. Also use the straight edge against the rails not the ties. I pre drill small holes in ties, then use tight fitting nails in the holes, then push or tap the nail in place. Homasote is my rail bed.   

Final check is eyeball, especially on curves.

If you want perfectly straight track, regardless of length, use a laser on one of the rails.

I have no such worries.  I model the Rock Island.  No straight edges needed when laying track.   

Mixed Freight posted:

I have no such worries.  I model the Rock Island.  No straight edges needed when laying track.   

It could be worse if you model Penn Central.

I have a 3 track main and used a string line on the 1st run then measured from rail to rail for the other 2.

Mikey

I see RRDoc already posted a pic of a notched block above, but I found the post showing the other ones I saw recently for a look at more of them. Here is a link to the post.

I used blocks as shown in the linked post with notches on the edges. RRDoc's with the notches on the flat, wide part of the block look like they might be better for the straight runs as they align a larger section of track all at once. I'd still use the straight edge as much as possible, but the 2nd opinion the blocks gives you can come in handy. They are also very good for short runs and keeping centers on curves.

DKDKRD's plan above of using the long board with the rail grooves lengthwise sounds like a great idea too. That sounds almost goof-proof! 

I hate to sound lazy but I used 30" sections of tubular and aligned them with a straight edge. The trick is finding your reference, in other words in my case the track could be straight when the sections are compared but not straight (i.e. parallel) with the reference, which in my case was the table edge.  In the end, after doing my best with the aluminum straight edge I put my head down on the track and adjusted by line of sight.

Don

Thanks for all of the replies.  I set up my brand new table saw my wife got me for Christmas and made a nice long rectangular piece to fit between the rails of two tracks at the spacing I desired.  You can see track two starts off bad right from the beginning.  Look how far it's off by the end!!!

Thanks again!

Ron

Ron, Looking good!

Don, I’m with you.  Reminds me of a college professor I had 45 years ago, who would give us electronic schematics and tell us to eyeball it.

Much better...

ADCX Rob posted:

Mixed Freight posted:

I have no such worries.  I model the Rock Island.  No straight edges needed when laying track.   

It could be worse if you model Penn Central.

Maybe the RI was in competition with the PC for the best "Deferred Maintenance" program.  

I'm on the prototypical side as well. "Generally" straight is good enough. Perfect symmetry and track work do not go together.

Nice job RONO45.

How to keep track straight   laser alignment also templates made from paint stirrers

That picture was not straight also use micrometer more as a gauge for spacing

I used my original equipment Mark three eyeballs to line things up.  Since the ROW was intended to be a bit older and worn the look works for me.

It looks like you're using Atlas track...it looks strait to me save the joints. Sometimes uneven ballast application, dirty spots, and even light reflection will give an illusion of crookedness.

For some Ross 28" straits, especially aged ones, I found I need to screw them down (1x4 phillip head countersunk) and then use a wood block and hit with hammer laid across the edges of 8 or so ties to straiten some of the kinks - use some gently taps at first and note movement, and then put in another screw and so on.