i would like to add grab irons on the left side of both of my BB SW7s. There are no dimples or any other guides. I've seen plenty of fine models with them added, and I can think of a half dozen ways to do it.
But my question is, what is the best way to add the grabs, with correct height and proper spacing?
My guess is probably a jig, but out of what material?
Help!
Jim (with a nod to Mies Van Der Rohe)
Yes, you should use a jig. Or is it a fixture? Unless you have a milling machine. Anyway:
The best material would be brass. But it's a real pain to drill little teeny holes in it.
For just doing it twice or so, as you are planning, you can use styrene. It would be thicker than brass. I would think .040" would work. It'll be a bit more pleasant to drill, I think.
You've got two "problems": one is to get your holes EXACTLY arrayed. And, if you use plastic, vertical ( so the drill hits just right after it goes through the plastic jig). It can certainly done by eye/hand, if you take proper care. And it is surely easier than trying to do the same thing on the side of the model. And you only have to do it once, with a jig.
The other one is actually easier with the plastic: you've got to set your new jig up to land in exactly the right place. Of course, the deck will easily place it vertically. For horizontal, I recommend having the plastic sheet go all the way to the front (left) and past. Then glue on a "stop" to its back to position the grabs, left-to-right. Conveniently, this will also give you a section to place a teeny c-clamp (or two!) to lock the jig into place while you work. Where the clamps go, I'd add another layer of .040" for cushioning. You might even go farther to the right with the plastic for another clamping position. You DON'T want it to move after you've got it exactly right.
Ed
You really need a jig - BLMA has a nice one that is photo-etched brass with holes for several types of grab irons. BLMA got bought by Atlas, and I am not sure if that item is in production right now.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
Sadly, it looks like the BLMA website has disappeared, so no more "lookin stuff up", there.
Send a note or call Atlas. They aquired the BLMA inventory. They might have part #4500 (grab iron drill template) in their collection of BLMA stuff. This is one on eBay right now, but the bidding is up to $15 for something that sold for $5...
I have a jig, of sorts. It might have come with a Tichy Reefer a couple decades ago. It is just a piece of styrene with parallel series of holes.
Get a piece of styrene, figure out your vertical and horizontal spacing, mark the location of the holes with a push pin and get out your microdrill.
Henry
COB Potomac & Northern
Shenandoah Valley
I'd skip the jig or fixture, as all you need is a small square and a divider (that's a draughting compass with two pointy-bits for you computer folks).Decide where you want to place the grabirons, then use the square to draw or lightly scribe a line perpendicular to the locomotives walkway. This represents where one side of the grabirons will be fastened to the locomotive. Next, set the divider so that the points match the width of the grabirons you're using, then place one point at the base of the line scribed previously, and use the other end to make another mark adjacent to the first. Align the square with the new mark and draw or scribe another vertical line. If you're working from a photo of the prototype, count the number of grabirons needed and decide if the spacing of the bottom grab up from the walkway is consistent with the spacing between successive grabs. Use hood latches and hinges as height markers to help you estimate the spacing - a scale rule for use on your model is helpful, too. Once you've determined the spacing, set the divider to match that measurement, then, starting with one point of the divider at the walkway, "walk" it up each of the vertical lines, lightly pressing the point into the plastic at each step.All that's needed next is to use your pin vise to drill the holes at each already-centre-punched location.
When installing the grabs, I put them all in place, then install a spacer between them and the body shell. I use a strip of .030"x.100" styrene. Whatever thickness of spacer you use, make sure that the strip is narrow enough that it doesn't touch the grabirons on either side where they enter the body shell.Next, use your fingers to press the grabs tightly against the spacer, then, using the back (non-sharpened) edge of your X-Acto in your free hand, bend the ends of the grabirons over inside the body shell - I usually bend them towards their counterpart on the same grab. Now, after ensuring that the spacer is properly placed (not touching the grabs where they enter the shell) press the grabs firmly against it and apply ca to each grab on the inside of the body shell. Allow the ca to set before removing the spacer. I find that the tip of an old #11 blade, in the handle, is an excellent applicator for ca: place a little on the tip of the blade then touch it the wire where it protrudes into the shell. The handle gives you better reach without blocking your view, and application of the ca is more precise.
If, after all the care you've taken, your grabirons don't look so hot, it's probably because you've drilled the holes not-perpendicular the the surface of the loco's side. I do so more often than not, but the solution is easy...
Here's some newly-installed crooked grabs on a Tyco gondola...
...using small, smooth-jawed pliers, grasp the offending grabiron as shown below, then rotate handles of the pliers gently up or down as suits the situation...
...repeat as necessary...
...until things look right...
This method is quick and easy, and believe me, I do lots of grabirons:
You can also use dividers to keep things even and level when placing masking tape for colour separations or lines on cars or locos, and they're useful when applying decals for the same reason. I also use them to transfer measurements when batch-building multiple cars of the same type. Dividers are probably the second most-used tools on my workbench, after X-Acto knives.
EDIT:
Doh! I probably should have included these photos, since you're doing Blue Box switchers:
The method works for hood units, too...
...and cab units:
Wayne
Wayne,
Thank you for this Grabirons 101 lesson.
The pictured reefer car has black grab irons. Did you paint them before or after installing them?
Guy
Modeling CNR in the 50's
Thank you to everyone who has responded, and to any future responders.
Lots of good information, which will be very useful not only to me, but possibly other readers who have wondered how to do this.
Thanks again.
Guy, since I use the small smooth-jawed pliers, shown in a couple of the earlier photos, to install the grabirons, all painting is done after installation...otherwise, the handling with pliers would remove the paint.
Here are a couple of photos of that car under construction:
As you can see, the car is from Accurail, which allowed the sides to be painted separately, before installing them on the car. All of the black ironwork on the orange portions of the car was done using a brush.That car represents the original version of the Santa Fe's USRA reefers, but they were later rebuilt as steel cars. I built two of those, and used undecorated Intermountain kits to represent them, so had to mask for the two-colour paint job. I also replaced the grabirons and sill steps with metal parts, and all of the black ironwork on the cars' sides was done with a brush.
Decals on all three cars are a combination of ones from Champ, Microscale, and C&BT Shops.These cars later got the "map" scheme, as shown on this Intermountain car, built from a factory-decorated kit:
That paint scheme, however, is a little too modern for my late '30s layout, and that car has gone to a friend who models the '50s.