The Home Machinist!

I'm guessing that "coach bolts" would be equivalent to "carriage bolts" in U.S. terminology. I think fiber-reinforced concrete would be more economical than using rebar. The fiber-reinforced concrete is commonly used for building footings without rebar in the concrete.

Interesting that they went with alternating bolts in the ties - one tie with bolts outside the rail, alternating the next with inside bolts. Wonder if that was standard English practice on NG lines...??

I could see embedding a threaded concrete anchor, with a hook on the bottom end in the wet cement, then skipping the insert and separate bolts. But, what a mess trying to transport and stack bunches of ties with 2” studs sticking out the top sides... probably better to install inserts and use fasteners, during layup.

Glenn

Glenn Brooks wrote: ↑Fri Apr 16, 2021 10:33 pm Interesting that they went with alternating bolts in the ties - one tie with bolts outside the rail, alternating the next with inside bolts. Wonder if that was standard English practice on NG lines...??
Glenn

No, it's not. I suppose they did it that way to save on the cost of fasteners. It apparently worked fine, the rail won't 'spring' any between two ties.

Mike

Fender wrote: ↑Fri Apr 16, 2021 8:44 pm I'm guessing that "coach bolts" would be equivalent to "carriage bolts" in U.S. terminology. I think fiber-reinforced concrete would be more economical than using rebar. The fiber-reinforced concrete is commonly used for building footings without rebar in the concrete.

"Lag screws (US) or coach screws (UK, Australia, and New Zealand) (also referred to as lag bolts or coach bolts, although this is a misnomer) are large wood screws. The head is typically an external hex. Metric hex-headed lag screws are covered by DIN 571. Inch square-headed and hex-headed lag screws are covered by ASME B18.2.1."

Mike

I'm disappointed but not discouraged. I poured the concrete way too stiff to properly fill the form and got lots of honeycomb, my homemade external vibrators weren't up to the job and even though I oiled the forms heavily the old dry wood I used soaked up water and swelled the form making it difficult to strip. I'm not too happy with Sakrete either, no coarse aggregate, I had to add my own, and from the way it mixed not much cement either. So...I'll have the powers that be at my club look at the result, and if they think it has potential I'll spend the time to make a steel form and try again, hopefully with better results.

Something that small, I don’t think you want any aggregate mixed in. Maybe Just go for high grade cement and sand...

Glenn

Glenn, my coarse aggregate wasn't that large, 1/2" crushed stone in a tie cross section 1-1/2"X 1-1/2", good concrete is made of cement, water, fine and coarse aggregate properly proportioned, and that's not what I used. I don't like Sakrete for the reasons I stated, I was looking for Quikrete, which I always had good results with, but Lowes must have switched brands since the last time I bought. In precasting plants concrete is placed with very low water content to maximize strength, in order to get a good form fill they have some wickedly powerful external vibrators on the form to consolidate the stiff mix, my homemade vibrators just gave my form a little buzz, not enough to consolidate the mix I used. I also thought that I could make 2 or 3 experimental panels with wood forms, if I try this again it's going to be with steel forms, wood wicks water out of the concrete and swells making anything embedded in the concrete difficult to remove. I know all this, but for some stupid reason I thought I could sneak this by Mother Nature, and she got me....again.

^^^ Try adding some draft angle to your form, and then seal it with some kind of finish AND wax the crap out of it before each use. It will help greatly.
The concrete looks a touch dry and low in cement, I'd try a different brand as you already suggested.

Considering the amount of work involved in all this, perhaps a visit to an expert at a concrete company would be worthwhile.

Or an experienced civil engineer...or heaven forbid a civil engineering professor at a local establishment of higher learning.. or giggle...maybe somebody who works at Amtrak?

About a year ago we were looking at our club's 4-3/4" track and it was showing its age, we contacted a few plastic tie manufacturers but none seemed interested in making 1" scale ties. So when this topic came up it rejuvenated my interest in an alternative to wood and plastic ties. My thoughts were can we make these easily, economically and with the longevity to be worthwhile? I figured I'd make a few panels, put them in service and see how they fared. With labor and equipment out of the equation (all club volunteers) the cost per tie would be $1.28, somewhat competitive with plastic, if I make the form with 10 ties instead of 9, the cost per tie will be further reduced. I think I can do that because I threw away 1 tie worth of surplus concrete from a 80 lb. bag mix. The fact that the panel I made looks so bad isn't going to help convince the club that this may be an option, but who knows. If I refine the process I think I could prepare the form, mix, pour, cure and strip every 3 days... Hmm, I wonder if I'm going to live long enough the finish?
P.s.
There was 5 degrees of draft on everything in the form and I still had to knock the from apart and pry the ties spacers out to free the panel. I left it cure in the form 4 days to assure it had developed adequate strength. Something like this has to be club made, the cost to do this professionally would be prohibitive.

One can be disappointed in first attempts at doing a lot of things. A stick-to-it-ness in perfecting a particular outcome can also become costly.
If one has "deep pockets" and you're building something from scratch, you're considered eccentric.
If you're poor, and wanting to do something "outside the box", you're considered crazy.

I give a hearty applause to jscarmozza for publicly showing his early experimental concrete casting results.
We never see very many photos of the scrap bins all machinists have in their shops for discarding their attempts at something
they've turned into a boat anchor. So, again... thanks for posting your experimental efforts.

As rkcarguy noted about creating more "draft angle to your form..." this is something I also noticed.

You are on the right track in using wood for constructing your forms.
Building a steel form is going to raise your cost and time factor, and could possibly fill your scrap bin if it proves defective in design.
A well thought-out taper to a wood form will help in allowing the cured concrete to be removed.

In addition, [amazingly]... cooking spray applied to a wood form makes a very good mold release when working with concrete.
It's considered helpful to think in reverse when designing your forms. Think about what will assist in extracting the cured concrete.
Notched out voids incorporated into the form design can be used for prying points for example.

The topic of concrete ties has been something I've explored over the decades. As Kimball McGinley mentioned earlier in this thread,
Bill Fitt's track located near Cadillac, Michigan during his era utilized concrete medium for track ties. The task and "sweat" of making them
I seem to remember was reflected in the Modeltec write-up as well.

I'm recalling Mr. Fitt's ties resembled a 2 X 4 dimension in size, and mechanical fasteners were embedded into the castings that became rusty.
His track... like a portion of the one I'm presently constructing was located in Michigan woods. It's a brutal environment for
a miniature railroad track. Every fall, the leaves bury it, and the lack of sunlight contributes to things always being somewhat damp.
Hence, it's what could have been the possible reason for adopting the use of concrete back then... though I don't know this specifically.

Innovation is glamorous, grabs the headlines, but it is also often overrated.
The maintenance that soon follows most everything becomes the reality.
A concrete tie does seem like a good idea.
The future for outdoor miniature railroads seeking an escape from maintenance though... is going to be in plastics, and composites.
How this becomes economically feasible for the weekend railroad builder doing it on their own does still linger toward cost prohibitive-ness.

In entertaining the idea of making a concrete tie myself, I've looked at all the additional required components a prototype full-size track tie
has engineered into its function. Google "concrete tie" or "concrete sleeper", and explore all the additional parts and pieces necessary for their function. Many of these additional fastening items would not come into play related to a miniature railroad track however.

The cost of building materials right now is insane. I'm hopeful they simmer back down at some point... for I'm considering using
schedule 40 PVC electrical conduit for portions of my track buried in the woods.

What!!!! ? A plastic pipe for a railroad tie?

Yep.

Massive weights of heavy cast iron and steel rolling on my line do not exist. And PVC does not have galvanic corrosion issues
related to its mating with an an aluminum extrusion.

Yes, consider it a "pipe dream". This, coming from the guy who invented the first actual working searchlight signal for the hobby...
which I'd rather be making again right now but can't because I've been building a workshop for the past three years!!!! (smiling ; )

But back on topic. A concrete tie is just a neat thing if you can make one to your liking. I'd keep trying.

John

Post Script:
As Bill Shields hinted earlier related to creosote, things were a lot easier for longevity when we had lead in paint,
and Penta was available for treating miniature railroad track ties.