# Building a Howe truss bridge



## Crusty Old Shellback (Jun 3, 2013)

Hi all. I have decided to build a Howe Truss bridge to use as a display for my 55T 3 truck Shay as well as use on my temporary Christmas layout. I have done some searching on the net and found a few sets of plans, including a actual set of drawings from a 1920 covered Howe bridge, along with a few build blogs. That's also how I found this site. Armed with some information, I have drawn up my palns and am now setting my sites on building. I do have a few questions for those who have gone down this path before me.

The basic deminsions are 3 feet long, 10" tall and 10" wide. I have a buddy who is making me some HACMATAC plates to use on the bridge based on the 1920 drawings but with the angles adjusted to fit my drawings. The truss rods are spaced at 4.5".

My questions are as follows:
1. Is 1/2 X 3/4 too large for the bottom chord? This is a scale 10 X 15.
2. Would a 3/32" rod be the right size?
3. I'm looking at 1/2" X 1/2" for teh main cross beams and 1/2" X 1/4" for the counter cross beams on the side trusses. Does this seam right?
4. My cross ties will be 1/2 X 1/2. That should be close enough right?
5. I am thinking of using Maple for my wood. Or is there some other wood I should be looking for? This bridge will be indoors. But I do plan on weathering it to make it look more realistic. 

I'm trying my best to use scale lumber based on the plans I have found on line. I have the tools to cut/plane the lumber to any size I need if these sizes are not correct. 

Thanks for any input. I'll be sure to post pictures of my progress as I go along.


----------



## SteveC (Jan 2, 2008)

While I realize the following is related to a deck-truss Howe bridge and not a through-truss Howe bridge, but both examples are 1:20.3 and Bob gives a really good description of what & why he does things. One topic was posted back in 2007 and the other in 2011. I think that you'll find them of help in your quest and I'm sure Bob would gladly answer any questions you may have. Feel free to download copies of the files if you wish









Bob Sorenson - Howe Deck-truss Bridge c. 2007 (PDF 4.13MB)[/b]

Bob Sorenson - Howe Deck-truss Bridge c. 2011 (PDF 1.3MB)[/b]


----------



## Dean Whipple (Jan 2, 2008)

I built mine about 10 years ago......









4largescale.com/trains/P27.htm[/b]


----------



## peter bunce (Dec 29, 2007)

Hi,

I would suggest that you make it a bit higher - mine is 9.5 inches wide and 12 inches high - here is a photo of it when it was just finished
















The tension rods are 1/16" welding rods and are mainly cosmetic - underneath the bridge are a couple of steel square section tubes (from a DIY Outlet) that give it its strength. Mine is just over 4 foot long - that is as long as I can make it as past that you cannot get your arm in to clean the track.

The black plates are styrene.


It is made from Sintra board strips, with little roof shaped pieces that the strips are glued onto. Finally the whole thing was painted. Don't forget to add the (inside the track) guard rails, with the surface of them just below the track - mine are agaion Sintra board strips.

Good luck, with the building. 

Yours Peter.


----------



## Crusty Old Shellback (Jun 3, 2013)

Thanks everyone. 

Steve, I had found the second link you osted and have it but could not find the first one you posted when I went searching for it. Thanks for posting them. 

I guess I'm just second guessing myself on the sizes with me going from N scale to G scale. It's hard to tell from just pictures what the sizes are. But from what Steve posted, it looks like I'm on the right track. 

Nice looking bridges you guys have built. Mine will be more on the style of what Peter has built, but with angled ends vice square ends.


----------



## Crusty Old Shellback (Jun 3, 2013)

Ok, I've got some more work done on my venture of building a Howe truss bridge.

After looking at the plans posted above, along with some pictures of actual bridges and some home built one, albeit very nice ones at that, I came up with a plan and made some crude drawings on paper. My bridge will be 3 feet long, which comes out to a scale 61 foot long bridge. I decided to make my cords out of 1/2 X 3/4 X 9.5 inch long lumber which is a scale 10" X 15" X 16' long lumber. I didn't want a bunch of long pieces as that would not look right. I have no idea where you could find a bunch of 10 X 15 that was 60 feet long. 

The plan is to take the 9.5" long lumber and stack it 3 wide with offset joints. I will make some tie plates and thru bolt them to hold everything together and make it look more realistic. I have glued the pieces together first just until I get done sanding them and then will bolt them. 

Now here is where things get a bit different but hey, it's my railroad. I know I first said I was going for the old weathered look. But while looking thru my local Woodkraft store, I found some beautiful lumber on a clearance table. I'm talking 75% off of some expensive lumber. So I snagged some up. Now while the bridge for the most part will look authentic, the wood on the other hand is a woodworkers dream. So heres some pictures of the wood I found. I sanded it thru 1200 grit to make it nice and smooth.

First up is Granadillo. It is used as a substitute for rose wood since you can't get the good stuff anymore. This will be used for the cords and cross members. basically the main part of the bridge.



Next is Katalox. Since it is a dark wood, I will be using it for the ties.



Last is Cortez, which I found out is also called Yellow Ipe. I'll use it for the top wind braces and maybe the stringers for the Ties to sit on.



Here they are all three together and have been wetted to show the color of when a finnish is applied.



Last but not least. I got one bottom cord glued up. Now I just need to glue up the other three cords and sand them all down. Then it's on to finding the hardware I want to use.







More to come later when I get more done.


----------



## Russell Miller (Jan 3, 2008)

Take a look at this topic: http://www.mylargescale.com/Communi...fault.aspx
My Howe Truss was based on this prototype.
Russ Miller


----------



## Totalwrecker (Feb 26, 2009)

Russ, link is broken. I think it needs a space after the colon behind topic: http...


----------



## Crusty Old Shellback (Jun 3, 2013)

Bridge looks good Russ.

I found some pictures of that bridge when I was doing my research and used some design elements from it when designing mine.


----------



## Jerry Barnes (Jan 2, 2008)

I used the plans from Garden Texture plans. I think they have a redwood kit of it also. 
Bridge Plans


----------



## Crusty Old Shellback (Jun 3, 2013)

OK, more progress. I got my upper and lower chords glued together, cut to size and sanded with 220. I also ordered my hardware I needed from Mcmaster-carr. Got a 2-56 for the small stuff and 3-48 for the truss rods. Should be here this week and I can start drilling. 

I've found a couple of different ways the bridges were made. On the chords, some had steel plates at the joints while others just had thru bolts evenly spaced along the chord. Not sure which way I want to go yet. Also I'm trying to figure out if I want to thru bolt the cross beams or nail them.


----------



## Crusty Old Shellback (Jun 3, 2013)

Well I finally got some hardware in from Mcmasters-Carr and figured out how I was going to bolt these pieces together. I sped the bolts at a scale 16" on center. So what do you think? Once I get everything cut and filed smooth, I'll pant them black.


----------



## Crusty Old Shellback (Jun 3, 2013)

OK, after about 6 months now, I've finally made some progress. I have been working with a buddy machinist at work to make me up some angle blocks. He machined them out of aluminum for me with a 60 degree angle on them. I used the plans for them that I found on line and made them in 1:23 scale. he made some long bar stock of them, then we marked and drilled the holes and I cut them to length with a scroll saw.   I also spent some time threading some & rods to 3-48. These will be the tension rods.


----------



## Crusty Old Shellback (Jun 3, 2013)

Next step was some initial assembly to see if this was even going to wrok. The pictures tell the story.


----------



## Crusty Old Shellback (Jun 3, 2013)

Next is the cross bracing and then tightening up the tension rods to hold it all together.      Everything is in place and then I started tightening from the middle out. Seems to have worked OK.


----------



## Crusty Old Shellback (Jun 3, 2013)

Here's the finished product. I need to do some tweaking on it but that will wait until final assembly. I'm going to paint all of the metal black. I still need to cut them all down to length. And I need to oil the wood after final sanding. I also have some U channel that I need to cut down and drill. It will go on the outside top and bottom of the long rails.


----------



## Crusty Old Shellback (Jun 3, 2013)

Ok, time for another update. While I was MIA, I did a basic assembly of the top, bottom and sides. It works. But I also found out that I need to build the bottom first, and then install the track, or I'll never get the track work in the bridge securely. So off I went. First off is the bottom. It's built the same as the sides except there are only 2 cross beams instead of three like the sides. I'm also thinking of putting a beam straight across at each end as well. In the pictures you can also see the "U" channel that I cut for the outside where the rods come thru. I painted it all with a ACE hardware rustolem style black paint.


----------



## Crusty Old Shellback (Jun 3, 2013)

My next step was to build a set of runners that will run the length of the bridge. On this will be the cross ties and track. I built them and placed them so that the track will run between the pair of beams on each side.  next was to add in all of the ties. They are 1/2" square and there are 50 of them.   Of course on top will be the tie plates and rail, which I still have to paint.


----------



## Crusty Old Shellback (Jun 3, 2013)

The next thing I did was to laminate up 3 beams for cross beams. These will sit on top of the bottom stringers and the long beams/ties/rail will sit on top of that. I've got them all made up but need to decided how I want to attach them, glue or bolts. Also to install them, I need them spaced so that the bottom angle piece and side angled stringers will clear them when installed.  This is basically what the bottom of the bridge will look like when done. The wood on the bottom section has already had a coat of Danish oil applied. The stringers and ties have not. Hence the different sheen.


----------



## jwalls110 (Dec 12, 2012)

Awesome!


----------



## Crusty Old Shellback (Jun 3, 2013)

Thanks Jeff. Ok, I got some more work done. I got my tie plates painted black. Painted my rail rail brown, and went thru the hard part of spiking rail. Boy that wasn't easy with the hard wood. Even though I predrilled the hoels, I still bent a bunch of spikes. But it's all done now. I used a 4' section of LGB track. I left some of the plastic ties on the ends and the jointers for now.


----------



## Crusty Old Shellback (Jun 3, 2013)

I finally got around to bolting down the cross members for the base. I've got to wait on some more & nuts,wahser,lock washers so I can finish it. But I'm making progress. The small black U channel was cut from some aluminum and painted black.   The rails set in place. I still need to figure out how I'm going to mount it to the bridge base. I've got a few ideas, just need to finish the base and then see which works best.


----------



## Crusty Old Shellback (Jun 3, 2013)

One of the reasons for all of the nuts and bolts is not only to make it look more realistic, but they are actually holding the bridge together. There is very little glue so far. And if the glue does fail in those parts, the nuts and bolts will still hold it together.


----------



## Crusty Old Shellback (Jun 3, 2013)

Well I never did quite figure out how to mount my Track section to the bridge so for now, I just glued it down hoping it will hold. I've got some aluminum flat stock that I'm thinking of cutting down to fit between the ties and use that to bolt down the track. But for now, it's just glued.

But things have progressed along and the bridge is complete. Next step will be to add in the little details. But I've got it built and installed in my small garage layout so I can at least run trains across it. It's almost a little short in that if I have the roof vent on my Shay open all the way, it will hit.

Anyways, on with the pictures.

First thing was to place the base upside down on some 1 G paint cans and put all of the tension rods in.




Next I drilled holes in the cross plates and mounted them and then flat washers, lock washers and nuts.


----------



## Crusty Old Shellback (Jun 3, 2013)

The next task was to turn the whole assembly over without any of the tension rods sliding out. I can honestly say that none of them fell out. After that, I placed the angled blocks that I had machined out of some aluminum. And then the crossed angled uprights and another angled block on top of them.


----------



## Crusty Old Shellback (Jun 3, 2013)

Now comes the fun part. trying to put on the assembled top section. What fun it was to align all of the truss rods to go in the right holes.



Then it's just a repeat of what I did on the bottom. Mark and drill the bracing, install it and then flat washers, lock washers and nuts.



Now the real fun begins. I started at the center tension rods and worked my way outwards on one side, then the other, tightening them up. I also had to make sure the angled beams were aligned properly. It took awhile but it's finally done. And there is a completed bridge.





I cut off the extra threads sticking up and then painted them black. I've still got a little more touch up paint to do.


----------



## Crusty Old Shellback (Jun 3, 2013)

And then I mounted it in my garage layout and made the first inaugural test run with my Bachman 3 truck shay and some USAt box cars and a Phil's Narrow gauge Gramps tanker I built.


----------



## Joe Johnson (Jan 2, 2008)

After doing some quick mental calculations, if you tension the rods correctly that thing should carry your shay, yourself and a couple of close friends if they would all fit!


----------



## Crusty Old Shellback (Jun 3, 2013)

Guess I kind of over built it then. But that's OK.


----------



## BigRedOne (Dec 13, 2012)

That is exquisite work! Looks lovely.


----------



## Joe Johnson (Jan 2, 2008)

Overbuilt is good. During our big drought I had an oak tree come down across my truss bridge and it held up the tree. I had to use a chain saw just to get to the bridge. Repaired three panels in a couple of afternoons and it was back in service. 

I always do an engineering test on my bridges. I'm an engineer so I sit on them. If they hold my weight they get "engineering approval."


----------



## Crusty Old Shellback (Jun 3, 2013)

Joe Johnson said:


> I always do an engineering test on my bridges. I'm an engineer so I sit on them. If they hold my weight they get "engineering approval."


 Might have to try that one. 

Thanks for the complement Big Red. Wood working is one of my other hobbies that I enjoy.


----------



## Zigeuner (Mar 9, 2013)

Deleted.


----------



## armorsmith (Jun 1, 2008)

I can't decide if it is a model railroad structure or a piece of fine furniture!!
Bob C.


----------



## Zigeuner (Mar 9, 2013)

Deleted.


----------



## Crusty Old Shellback (Jun 3, 2013)

Well I finally got around to doing some detail work. I added in some oak "planks" to walk on and a ladder to climb to the top of the bridge. 

Now I'm looking for/building some fire barrels and a "no fishing from bridge sign". Then of course I'll have to have the requisite kids fishing from the bridge. 

I also included a few pictures of my new to me Bachman Spectrum 25T Climax that's 20+ years old that I picked up this past weekend at Arnies trains and my resident 55T 3 truck Shay.

http://smg.photobucket.com/user/blo...ild/Howe truss bridge/81_zps297274d4.jpg.html



http://smg.photobucket.com/user/blo...ild/Howe truss bridge/83_zpsa9bbaa8a.jpg.html


----------



## Crusty Old Shellback (Jun 3, 2013)




----------



## carlhandup (Sep 7, 2014)

Where did you purchase the metal threaded rods?


----------



## mikell (Apr 27, 2014)

The state stopped by to inspect our 15" gage for the city. He jumped up and down on one of our low bridges to see if it shook then progressed to the bigger ones doing the same thing. All passed


----------



## Crusty Old Shellback (Jun 3, 2013)

carlhandup said:


> Where did you purchase the metal threaded rods?


I bought the rods and a die from fastnal and threaded them myself. The rods come in 6' lengths. You can also get them at Grainger I believe. They are a #3 rod and die if I remember correctly.


----------



## placitassteam (Jan 2, 2008)

Beautiful work! Is that walnut? It is too pretty to paint or leave outside! All those nuts and bolts are impressive.


----------



## Crusty Old Shellback (Jun 3, 2013)

Thanks. No it is not Walnut. Look on page one, post #6 for their names and a good picture of the wood. One is supposed to be the new rosewood.

yes it took some time to make all of the threaded rods. Some are a #2 and some a #3. The angles and square "hardware" are all aluminum.

Right now it's sitting on my shelf layout in the garage. I'll probably move it into the house when I set up my Christmas layout and find a way to put it in the layout. Eventually I'm hoping to have it in my outside layout when I build it. Just have to keep the wood well oiled.


----------

