Trying to fasten a MicroTrains perforated roofwalk to a styrene car body.

[nickelplate759]

I have an old Bachmann 50' plug-door boxcar body that I want to put a new MicroTrains perforated 50' roofwalk on. 
I can make it fit, after drilling some oversize holes for the pins of the MicroTrains roofwalk,  but I'm stumped as to how to actually fasten it in place.

I'm pretty sure that the roofwalk was intended to be a press fit into a MicroTrains car.  That's not happening here, the holes are necessarily too loose for that.  I think need glue, or something like that.  My first thought was epoxy in the roof holes, but the roofwalk appears to be Delrin-like and I'm not confident it will hold.

One wacky idea is to thread the roofwalk pins and add interior washers and nuts.  I've no idea if that will work.

Anyone have any successful experience to share?

[peteski]

I guess I'm not familiar with the perforated roofwalk. The older ones were molded from polystyrene (same as the car bodies) and press fit into the holes in the roof.   I never knew MTL was selling some new version.  I have my doubts that it is DELRIN (POM plastic).  Even if it is, if you roughen the pins a little, epoxy will hold. Or simply take soldering iron and melt the pins on the inside of the roof.

If it really is DELIRN, paint will not stick either.

[robert3985]

Eventually, on all my cars, I was planning on improving the running boards with either direct replacement with Plano etched SS running boards, or snipping the mounting pegs off of MTL running boards, sanding them thinner, then gluing them on.  Other cars from other brands would get similar treatments depending on the models.

However, now that Plano is out of business, that part of my plan probably isn't gonna work any longer, so, looking at newly manufactured models of cars that have running boards, it appears that the newly manufactured ones have vastly improved running boards over most cars from 20 years ago or longer.

But, some are just re-runs of old models that still have grossly oversized running boards, most of which can be either sanded down after snipping off the mounting pegs or replaced with MTL running boards...which used to be readily available and still might be relatively easy to get...most of which I still sand down.

Most of the time, I don't fill the mounting holes in the carbody, as they are underneath the running boards and are mostly not visible.  However, in some cases, they are visible, so they get filled with the mounting pegs I've cut off of the running board, glued in place with my Tenax-7R equivalent plastic welder and snipped close to the car roof, then filed/sanded flush, with a dab of paint that approximates the roof's color.

For my Plano running boards that I have left, I glue them on with canopy cement, applying a dab on two or three running board standoffs on one end of the car, making sure it's aligned as perfect as I can...and I hold it until the canopy cement is capable of holding the running board without my fingers pressing down (maybe 5 minutes).  I let it dry for an hour...or, I help it along with my old shop hair dryer set on "Medium" heat (so I don't melt or warp the plastic car body).  This speeds things up a lot...then, using a long, thin detail brush, I apply a small dab of canopy cement quickly on the rest of the standoffs, trying to only get it on the standoffs' very tops...then, I press down on the running board as evenly as I can, sometimes using a narrow steel rule until the glue starts to cure, then I help it along with my hair dryer again.

If you get some canopy glue slopped onto where it shouldn't be, you can easily remove the excess using a small fairly stiff watercolor brush that's wet with water before the cement fully dries.

Canopy glue is great stuff and dries very transparent and thin, and holds all sorts of varying materials very securely.  I use it a lot.

OR, I use my Tenax-7R plastic welder substitute methylene chloride (or dichloromethane) (you can buy it at your local chemistry store) which is what Tenax-7R was, to chemically weld the running board standoffs to the bottom of the sanded-down running board, using a small brush.  Don't apply too much, and use a slim brush that's smaller in diameter than the gap between the car roof and the bottom of the running board trying to hit the joint between the top of the standoff and the bottom of the running board.  This doesn't work for metal running boards, only plastic ones and not Delrin or other acetal plastics.

I don't find it necessary at all to use Epoxy, or sticky glue such as Walther's Goo, both of which are difficult to apply precisely.

Although I haven't done it, another possibility might be to use Artist's Matte Medium, or Mod-Podge Matte, which I think would be similar to Canopy Cement...especially for metal running boards, but might take longer to set up, but wouldn't be glossy.

Close-up photos don't lie, so...
 
Photo (1) - ...here's a close-up of a UP CA-1 caboose kitbashed from a couple of MTL Wood Caboose with sanded-down running boards viewed from the side, showing a complete lack of mounting pins...glued securely to the car body using Tenax-7R:


Photo (2) - Fine N-Scale resin kit with an etched brass running board attached with canopy cement to each running board standoff:


Although neither of these examples is of MTL's perforated running board, I am assuming either method I've described above would work to securely attach one to your old Bachmann boxcar...just snip off the old Bachmann mounting pins to fill the holes if you need to do that.

Cheerio!
Bob Gilmore

(edited for typos and grammar)

[nkalanaga]

Contact cement (my go-to is Seal-All) or similar should work.  Put it on the inside, around the pins.  It will stay flexible enough that the roofwalk can move if it shrinks or expands different from the car.  There shouldn't be any real stress on it to pull it out.

[randgust]

Anybody got a picture of an MT perforated roofwalk?

As we are discussing HOW, not the benefits of, it's different.    Trim off your old pins to fill the holes so you have a solid start and glue in.

If they have pins, then try this:    Press the new roofwalk on to a piece of paper of a semi-hard surface, leaving indentations.  That will leave marks you can see, and open up with a pin or smaller drill.  That's your template.  If you're doing more, transfer that spacing to brass or plastic material.

Now lay that over your car roof and use that to drill new proper sized holes for a press fit.

I just spent the last two evenings putting on some of my legacy stash of GMM etched brass roofwalks on old Atlas and Bachmann cars that were worth it, probably the thickest ones out there.  I used ACC with needle application after spray painting them a 'close' color, the ACC gets shiny so a second light coat of 'right' color gets applied with weathering.  Yeah, worth it.  The old GMM sets had stirrups on too, which is the other ugly part of those older cars.

[Mark5]

However, now that Plano is out of business,

Plano products are still around. When PF&S bought them, I emailed them specifically about the N scale products - the response was:

"We plan to continue the entire line of Plano Model Products."

However, it isn't yet exactly clear as to how to obtain them.

[peteski]

Plano products are still around. When PF&S bought them, I emailed them specifically about the N scale products - the response was:

"We plan to continue the entire line of Plano Model Products."

However, it isn't yet exactly clear as to how to obtain them.

By the same token, I wish someone would take over the entire Gold Medal Models line of photetched items, but with Loren Perry's passing earlier in the year, and ever stricter environmental regulations, that seems unlikely. Same can be said for Micron Art. Reynard produced lots of very useful photoetched  items, but that line also disappeared.

[nickelplate759]

I think MicroTrains came out with these with the last revision of their 40' and 50' PS1s - when they started body-mounting the couplers.
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There's a 50' version and a 40' version (shown).

[peteski]

Hmm, I wonder if  the -C in the old part number does mean Celcon (POM) plastic.  That would  make them difficult to paint.
@JoeD , would you have any info on this?

[nickelplate759]

Might be - they released these around the time that they started molding detail parts in colors to match the paint.   They only one I've used so far went on a black car, so if the paint doesn't stick I won't really see it.

[ntex]

1070 was the regular roofwalk part, 1070-C is the cored (c) roofwalk.

[Doug G.]

I would use contact cement, as Mr. Kalanaga said or E6000, either applied on the inside after the pins are stuck through the holes.

Doug