Using Blacken-It to weather FVM metal wheel sets

[benderda]

I used the search feature for Blacken-It and didn't get any hits relative to weathering wheel sets so I thought I'd just start a thread to ask if anyone else has tried this or has any experience with it?  I"m fairly pleased with the results as to the variety of texture and color that Blacken-it provides, although a rusty brown would probably be more prototypical.  If anyone is interested I will post pictures as best I can given the camera I have.   When compared to most prototype photographs that I've checked these compare quite well, in my opinion.

The problem is that the process is fairly labor-intensive, but as I have not not tried hand painting any wheels yet, I can't say if using Blacken-It is more work than painting or not.  I'm also still experimenting with different procedures and techniques and it appears that there may be easier ways to accomplish some of the tasks, such as cleaning the corrosion off of the wheel tread.  For the last batch of eight cars I just ran them around a test oval to clean off the tread and then just cleaned the track itself, rather than trying to clean each individual wheel tread.  That process seems to work fairly well, however, I was also using an ElecTrakClean at the same time, which I think simplified the track clean up process.

Once the tread and the needle point on the axle are cleaned up the rolling characteristics are the same as a non-blackened set of metal wheels.  I tested this out by creating a fixed incline, then using the same car, changing only the wheels sets, allowed it to roll down the incline (ala a pinewood derby race car), then measured the distance of how far the car rolled.   The tests were repeated multiple times to remove any outliers from the results.  Disappointingly, non of the metal wheel sets rolled as far as a clean set of Microtrains Derlin low profile wheels.  I was surprised by that result as the plastic wheels would consistently roll a significant distance farther.  However, be that as it may, I am pleased enough with these results that I intend to eventually convert all 300 cars in my inventory.

And as an additional side note, I had previously tested the pulling power of a 2-8-2 that I have and it would pull 27 IMRC 40' reefers with MTL trucks and wheels and a caboose without slipping the drivers.  That same engine will pull 25 of those same IMRC reefers with the weathered metal wheel sets.  I expect as those wheels acquire more running time they will continue to become smoother with less rolling friction and the number of cars that can be pulled will go up.

The main areas where I'm still experimenting and trying to come up with the most efficient procedure is 1) cleaning of the axle needle points and 2) cleaning the wheel tread, and whether the wheel tread needs to be cleaned by hand at all, or just let the running clean it up then clean the track afterward.

The pictures are quite bad and I apologize for that.  I need to learn how to take close-ups, but at least they should be good enough to give an idea about how the blackened wheels actually look.  I still need to weather the trucks themselves, but that will be a different project.  Thank you for any suggestions or ideas.

[mmagliaro]

I never blackened my FVM wheels, but I can tell you that MT Delrin wheelsets always put less drag on the train.   That's been my experience and I've read it from other users.  That slippery plastic on slippery plastic is very hard to beat.
Regardless, I'm willing to give up some pulling power to have the low profile Fox Valley wheels because they look and run so well.

[wazzou]

I never blackened my FVM wheels, but I can tell you that MT Delrin wheelsets always put less drag on the train.   That's been my experience and I've read it from other users.  That slippery plastic on slippery plastic is very hard to beat.
Regardless, I'm willing to give up some pulling power to have the low profile Fox Valley wheels because they look and run so well.

...and theoretically keep your track cleaner too.

[railnerd]

The problem is that the process is fairly labor-intensive, but as I have not not tried hand painting any wheels yet, I can't say if using Blacken-It is more work than painting or not.  I'm also still experimenting with different procedures and techniques and it appears that there may be easier ways to accomplish some of the tasks, such as cleaning the corrosion off of the wheel tread.  For the last batch of eight cars I just ran them around a test oval to clean off the tread and then just cleaned the track itself, rather than trying to clean each individual wheel tread.  That process seems to work fairly well, however, I was also using an ElecTrakClean at the same time, which I think simplified the track clean up process.

Microbrushes RULE: http://www.micromark.com/fine-microbrushes-pkg-of-30,8375.html

[DKS]

Although chemically blackening wheels may be labor-intensive, I'm not sure it's necessarily labor well spent. Painting may not be much more labor-intensive, and indeed may be easier, assuming you create some handy jigs for holding wheelsets and airbrush bunches of them at once.

IMO, painting is about the only way to achieve realistic coloration. Wheels on solid-journal trucks have a distinctive color, which is a combination of grease from the journals and dirt from the roadbed.



By contrast, wheels on roller-bearing trucks will tend to have a different color, which is basically the rust of the wheel with a dry dirt patina.



There are of course many variations, but these are the predominant colors.

I never blackened my FVM wheels, but I can tell you that MT Delrin wheelsets always put less drag on the train.   That's been my experience and I've read it from other users.  That slippery plastic on slippery plastic is very hard to beat.

That's very interesting. I ran some tests pitting Z scale trucks from Micro-Trains (plastic wheels) and Full Throttle (metal wheels). I found that the Full Throttle trucks had less drag--in fact, it was almost exactly half as much drag. Of course, that was Z scale, but it would surprise me if it was much different for N scale.

...and theoretically keep your track cleaner too.

Again, I've had a very different experience. After running trains on a large layout with a friend for many years, we found that plastic wheels resulted in the re-distribution of considerably more dirt than metal wheels. But, as in most things in life, YMMV.

[wazzou]

@DKS
That's what I was saying...that the metal wheel sets helped keep track cleaner than the delrin.
The comment followed Max noting his willingness to sacrifice free rolling qualities of delrin for the better appearing FVM wheels.

[bill pearce]

I can't believe that there is any increase in friction between plastic and plastic-metal. On one had we have self-lubricating engineering plastic axle points in self-lubricating plastic sideframes, or very polished or plated metal axle points in self-lubricating plastic sideframes shouldn't make a lot of difference. I can, however, see how cruddy plastic wheels will make for more friction than clean metal ones.

[Chris333]

I stick a whole pack of FVM wheels down on double sided masking tape and then airbrush them from the side at a 90 degree angle. This way no paint gets on the treads. I learned this from the great  .

[DKS]

I can't believe that there is any increase in friction between plastic and plastic-metal. On one had we have self-lubricating engineering plastic axle points in self-lubricating plastic sideframes, or very polished or plated metal axle points in self-lubricating plastic sideframes shouldn't make a lot of difference. I can, however, see how cruddy plastic wheels will make for more friction than clean metal ones.

I know it seems to defy logic. But the effect was very real, measurable and repeatable. I was also using brand new trucks, so there was no dirt to affect the results.

I have a feeling it may be due to shape and surface area. The cones on the ends of plastic axles are slightly blunted; this probably results in greater surface area at the contact point, whereas the metal cones are more sharply pointed, reducing the surface area between metal and plastic. This is just a theory; there may be other effects at play, such as friction being reduced when dissimilar materials are used (which is why motor and other bearings are something like bronze while the shafts are steel--steel on steel increases the friction substantially due to molecular bonding).

@DKS
That's what I was saying...that the metal wheel sets helped keep track cleaner than the delrin.
The comment followed Max noting his willingness to sacrifice free rolling qualities of delrin for the better appearing FVM wheels.

Got it. My bad.

[wazzou]

I stick a whole pack of FVM wheels down on double sided masking tape and then airbrush them from the side at a 90 degree angle. This way no paint gets on the treads. I learned this from the great  .

I made a wheel painting jig from styrene after seeing the idea from one offered for sale by American Model Builder's in HO. 

[jagged ben]

I typically paint my FVM wheel faces by hand.    Takes about a minute to do four wheels.  I use a wet blend of Modelmaster's rust and a Palmer acrylic color I found called "Forged Iron".  You could use any grimy gray or make your own; it's not like you have to match it from one batch to another.   (In my case airbrushing doesn't save time because it requires going to a location other than our small apartment, namely my parent's garage.  So I only do it for things that really require an airbrushed finish.) 

[railnerd]

I made a wheel painting jig from styrene after seeing the idea from one offered for sale by American Model Builder's in HO.

minuteman scale models also has a jig available:

http://www.minutemanscalemodels.com/product_p/302.htm

[sizemore]

I never blackened my FVM wheels, but I can tell you that MT Delrin wheelsets always put less drag on the train.   That's been my experience and I've read it from other users.  That slippery plastic on slippery plastic is very hard to beat.
Regardless, I'm willing to give up some pulling power to have the low profile Fox Valley wheels because they look and run so well.

I think it may be due to the added weight of the metal wheelset, compared to delrin. If the car has been weighted to proper NMRA spec, you're just adding more weight for the locomotive to pull. In the experiences I've had, the FVM wheels free-wheel better in MT trucks, but add lots of weight to the train when you're trying to pull longer strings of cars.

When I get around to chore of changing out the wheelsets in the fleet of cars, I wonder if I should remove some slugs from the internal weights to keep it within NMRA spec. I've read a story on here where the car had metal wheelsets and weights were removed completely but still had great operation. The side "benefit" being that the locomotives could pull "super" long trains with ease. If only I had a research lab and gobs of money to test it.

The S.

[Cajonpassfan]

I stick a whole pack of FVM wheels down on double sided masking tape and then airbrush them from the side at a 90 degree angle. This way no paint gets on the treads. I learned this from the great  .

Chris, say WHAT? I maybe a little slow, but I am missing something here.....how do the threads stay clean again? Presumably the flanges get the treatment and the threads don't?
I too wanna learn from the great
Otto K,

[C855B]

I think it may be due to the added weight of the metal wheelset, ...

You could have something there. I ran rolling-resistance tests right after the FVM wheels were first released, comparing MTL low-pro, MTL pizza-cutters and FVM on the same cars. It was a ramp setup into a runout course including 15"R curves, ostensibly to test flange drag. Within the very high variability of the ad-hoc test setup, MTL low-pro and FVM were a wash. Pizza cutters consistently ran 25-30% shorter through the course, demonstrating at least to me that flange drag was real.

An odd effect noticed was bearing heating, believe it or not. The ramp ejected the cars into the course probably at ~200smph. The test scheme was five consecutive runs with each wheelset in each car. Consistently, the Delrin-against-Delrin wheelsets would lose ~5% of their rollout distance with each run. Not that we're going to see that on our layouts (hopefully), but there it was.