Black Bear Arch Bridge

[ocalicreek]

Yes, another bridge thread. This one's a kit, however. Spent some hard-earned hobby swag on what seems to be a great product from Black Bear Construction Company and decided to document the progress here.

I have always had a fancy for the SS Ltd 'Dinky Creek' arch bridge, and this one has all the charm but at a fraction of the price - AND it comes with its own jig.

Here are some photos of what you get when you buy the kit. First, all the plan & instructions all layed out on my portable workbench. Supercool coffee mug not included.

[albumimg]3757[/albumimg]

Next, the hard resin jig:

[albumimg]3758[/albumimg]

This template is included as an overlay for your NWSL chopper or equivalent miter cutting device:

[albumimg]3759[/albumimg]

Finally, an end-on shot of the bundle of strip wood:

[albumimg]3760[/albumimg]

You can purchase either the jig or the materials pack separately, or together as I did.

I had been looking for a small truss bridge to fit a short location. Nothing from Campbell seemed to fit the bill and I didn't want to either kitbash one of their bridges or scratchbuild to fit the location. I had resigned myself to using an old Tyco bridge - heavily modified for better realism and less recognition as a cheap plastic toy train set bridge, but was still not happy with the heavy look. This little gem fits the bill quite nicely (and just barely - it's almost too wide...almost!).

Today after reading through the destructions and checking the parts/materials, I stained the stripwood and ties (not included) that I'll use on the bridge itself. The kit includes enough material to make trestle bents for the ends, but I'll be mounting the bridge directly on the abutments.

More to come after I begin assembly.

Galen

[e-paw]

Very cool. That Jig looks handy.don't forget to post in progress pics..Really want to see it all come together.

[ocalicreek]

Thanks, epaw. Here are a couple in-progress pictures:

[albumimg]3761[/albumimg]

[albumimg]3762[/albumimg]

I stained the wood a dark walnut color, the same as my hand-laid track ties. After weathering I think it makes a nice creosote color.

In the first picture you can see the basic outline of the bridge taking shape. The main structural member across the bottom is first and the feet/shoes added beneath that. Then the vertical members come next followed by the top chord members.

The second image shows the cutting template attached to my Chopper II. I just made sure the center line was beneath the blade then screwed it down using the holding clamps attached to the chopper. It's really a clever jig and template combo, but there's still some good old fashioned measuring to do, or at least the variety that involves laying the wood over the plans, marking where to cut, then carefully laying it beneath the chopper and THWAK!

This is turning out as I had hoped it would, to be a fun little kit. Not so huge as to be really tedious, but enough variety to keep it interesting. Of course, I haven't got to the NBW's yet...

I made a bit more progress tonight than shown here. I added the diagonal bracing to one side of one side, then set that aside to fully dry before flipping it over tomorrow and doing the other set of braces. While that was drying I started on the second arch, getting all the verticals in along with a few chord pieces before calling it a night. More to do this week, but I must say the step-by-step instructions and componant nature of the jig makes it easy to leave off and pick up again.

Galen

[mountaingoatgreg]

Galen,
YEAH MORE BRIDGES!!!!
I am disapointed that you did not draft your own plans and build your own jig though j/k
I am actually more jealous that you get to just assemble the "kit." Either way it looks like you are off to a grea start on your project and keep the photos coming!!!

[Mr Fixit]

Thats a great jig they included.

Imagine if they included jigs like that with model aeroplane kits, people would be knocking them out by the squadron.

Mark

[ocalicreek]

Thats a great jig they included.

Imagine if they included jigs like that with model aeroplane kits, people would be knocking them out by the squadron.

Mark

Mark - I hear that! One of my early (pre-teen) learning curve experiences was assembling a Guillows P-51 wood & tissue paper kit with rubber band drive. Had I known a mentor or kind-hearted hobby shop owner who was into such planes I may have spent more time with it, but as it was I dutifully layed out the plans, covered them with wax paper, and pinned each carefully cut rib & spar in place, gobbing on wood glue. Alas, it did not fly and actually self-destructed under an over-tightened rubber band.

Now I am carefully brushing on yellow carpenter's glue sparingly (do you call it yellow PVA down under or is that a Brit thing?) and mitering cuts on an NWSL chopper.

Greg - I'm glad I went the kit route. There will be other occasions to scratchbuild. In fact, I'm not using the trestle piers that came with this kit so they may show up foreshortened somewhere else someday. I have an idea for the low trestle that will cross a wide marshy creek on the removable 'bridge' section of the layout. When I get to that stage I'll most likely order another jig and some materials from Black Bear.

Still plugging away...

Galen

[Mr Fixit]

Galen;

Most PVA glues here in Australia are coloured white starting with Hobby PVA, Carpenters/ Cabinetmakers Interior PVA then Carpenters Interior/ Exterior PVA.

If you then need a stronger Exterior Glue you have to move up to the Polyurethane glues which are good until you get the stuff on your hands and have to try getting it off. Beyond that are the Marine use type glues which get very pricey.

Like everything nowdays when you go to Bunnings [our equivalent to Home Depot] the range of glues available boggles the mind, what with the different brands, sizes of bottles/dispensers, types of glues for various purposes and materials.

Makes ones head hurt.

Mark

[ocalicreek]

Staying up too late then getting up too early with the kiddos makes my head hurt.

Thanks for the cultural clarification. I'm always interested to learn about how differently we see the world, even something as simple as how we label our products. One more reason I think Big Blue is a great forum - the many folks from around our globe who post here.

Strange, though, I can read your words just fine. I half-expected them to be upside down on my screen.

Progress continues on the bridge. No new pictures at this time but hopefully soon, next chance I get to work on it.

Galen

[Steamtrains]

"Strange, though, I can read your words just fine. I half-expected them to be upside down on my screen. "
There's a little black box inside your computer - a gravitometer, in fact - and its only function is to straighten up words or pictures that originate in the southern hemisphere....

[Sumpter250]

There's a little black box inside your computer - a gravitometer, in fact - and its only function is to straighten up words or pictures that originate in the southern hemisphere....

It also functions in "the Southern Hemisphere", to straighten up words or pictures that originate in the Northern hemisphere............until the Earth's magnetic field changes polarity...then everyone's words and pictures will be Upside Down!
There will be a benefit to the field change....the "downside ? " will be UP! hock: .......and the UFO's will have a hard time navigating, until the aliens make the necessary corrections. ( according to the "ancient alien theorists" it's all done with magnetism ?........really !

[P5se Camelback]

.......and the UFO's will have a hard time navigating, until the aliens make the necessary corrections. ( according to the "ancient alien theorists" it's all done with magnetism ? ........really !

I had never heard what the ancient alien theorists had said when I was a child ...

... but it always seemed to me, since back when I played with two magnets on the kitchen table, waiting for 4:30 in the afternoon when the test pattern on TV would be replaced by Flash Gordon and Ming the Merciless, that rockets couldn't work in outer space ... but magnets would probably still push against each other or pull towards each other.

I knew I had been on to something back there in the '50's when I started seeing Mag-Lev vehicles in the '70's!

[ocalicreek]

Magnets! Yes, this is why I used magnets to make my first perpetual motion machine...and we all know how that turned out, at least those of us who know conventional physics. At that time I did not, but was learning all about it in a practical application sort of way.

This is turning into one heck of a train-of-thought thread! No worries, I'll bring us back on track.

The angle braces are on 3 out of 4 sides - two sets for each arch. One more set to cut and fit then I can move on to the next step. The instructions say to do steps 1-9 then repeat for the other arch. I did 1-4 or so and began on the other arch while the first dried. It will probably turn out that I have a bunch of nbw's to add all at once this way...but that's not terrible. Only 140, and a few of those were destined for the trestle bents which I'm not building for this particular bridge.

Okay...pictures later tonight or tomorrow morning.

Galen

[Gary S]

That's an interesting bridge and I've never seen a kit with a jig like that. Thanks for sharing! At first sight, it seems like this should go together quite easily, cut the pieces, add some glue, throw the pieces in the jig.... or is there more to it than that?

[ocalicreek]

That's an interesting bridge and I've never seen a kit with a jig like that. Thanks for sharing! At first sight, it seems like this should go together quite easily, cut the pieces, add some glue, throw the pieces in the jig.... or is there more to it than that?

So far, yes, it is that easy. The hardest part is measuring and making sure your cuts are true. The chopper has a tendancy to leave a cut end that isn't exactly true for thicker material so a light touch with a sanding stick is necessary.

Just finishing the evening's work so I'll be heading home and then doing more modeling work tonight.

Galen

[Sumpter250]

So far, yes, it is that easy. The hardest part is measuring and making sure your cuts are true. The chopper has a tendency to leave a cut end that isn't exactly true for thicker material so a light touch with a sanding stick is necessary. Galen

When exact length ( as is the case for stair treads, or similar items that really have to be exactly the same length ) is required, I test cut the first piece, measure the amount of " error ", reset the stop on the chopper for that amount of error, and use the NWSL "True Sander", to sand all the pieces to the correct length.
Styrene sheet, 0.060", can be used to make angle guides ( 30,45,60 degree or what ever ), to help when using the sander, to get a consistent angle cut.