Getting ready for signaling and detection and was looking for ideas and info to make my own resistance wheel sets,parts and where to buy them. Also any tips on how you made yours and the parts list or numbers. All my cars have metal wheels installed, I am using all Digitrax equipment. Saw a video on u tube but he was using N scale and 1k ohm resistors and conductive paint. Thanks Jim.
I haven’t done it myself yet, but I would go for these:
These are 10K ohm. I actually found a video that uses those exact resistors:
I use all Proto 2000 wheels and follow this pretty much exactly:
http://www.mpmrr.net/wheels1.html
My silver paint I got from eBay, a seller called semicro (it’s used for scanning electron microscope slides). It’s NOT cheap, but don’t use the carbon type paint, use silver. A little goes a long way, it hardly looks like my bottle has been touched and I did about 70 wheelsets. I have the 18% stuff but next time I want to try the 36%.
Since Proto wheels are blackened, I use a small burr on the dremelto clean up a small portion of the rear face of each wheel right down to the axle. You have to get right down tot he axle but not cut the wheel off. It’s the smallest burr in my Dremel set - really tiny - so you’re not goign to cut the axle in half unless you REALLY try. Do both wheels directly across from one another.
For gluing the resistors on, I got a bottle of a thick CA I actually foun at HD or Lowes, from Locktite. It comes in a bottle that has little squeeze arms on the side designed to dispense small drops and it worked perfectly. You need a VERY tiny drop of glu to hold the resisto, if it gets up on the edges where the conductive pads are, it will be useless since CA is an insulator.
What I did was put my wheelsets in one of those wheel painting jigs that holds 4, each witht he area I hit with the Dremel facing up. I pulled 4 resistors from the ammo tape reel the come on, and put a drop of CA on the axle right next to one wheel (instead of dead in the middle). Then using my magnifier light and a small tweezer, picked up and placed each resistor. Two of the sides are tined, these are the contacs. The size specified is rectangular, the long way goes parallel with the axle. While the CA was drying (it’s thick, takes a few minutes), I painted the wheel faces with a microbrush and some grimy black paint.
Once the CA was cured (if it’s not set it seems to react with the solvent in the silver paint, so don;t rush)
Thanks for the info I’ll be trying this out after I order everything, Jim.
I do something very similar to Randy. I use Intermountain wheel-sets (buy them in packs of 100) for the most part as they have a metal axle (whereas I think the Protos have a plastic axle). The intermountain wheels sets have an insulated end and a non-insulated end. These wheels are also blackened like those Randy described. I use and exacto to scrape the back of the wheel and the axle to clean off the blackener. I use the 603 size surface mount resistors (10,000 ohm). I use the tip of a Pin to apply the CA to the resistor and glue it at an angle over the plastic insulation on the insulated side of the wheel. I have a very fine pair of tweezers I use for this process. I then use another pin to apply the silver paint (I got mine from my local electronics surplus store). The Paint is quite thick (its used to repair traces on PCB’s) and a brush doesn’t work very well for me. I use the pin to apply a trace between the insulated wheel and the resistor and another from the resistor to the axle of the wheel-set. The reason I like the Intermountain wheelsets is because the tread doesn’t need to be polished and the metal axle can be used as a trace so there is no need to paint one all across the axle to the other wheel.
As previously stated, the traces will not conduct electricity until they are dry. I use a volt meter to check each wheel set. It should read within 5% of 10 K ohms.
I sit in front of the TV while doing this as it is a bit of monotonousness process.
I don’t bother to paint over the Resistor once it is installed because it is barely visible. The paint doesn’t even stand out. I will try to post pictures later when get home.
I do this to 50 wheelsets (of a package of 100). Each Car will get 2 wheelsets with the resistors and 2 that are blank (one of each goes on each end of the car).
Most of the club guys use Intermountain., I’m the oddball. Modeling a coal road, we have LOTS of open hoppers, where you can easily see the entire axle, so even with th esmall resistor int he corner, you cna see it on most cars. Maybe I’m just picky. I even noticed a few of mine that need touchups because they weren;t completely covered in the black paint.
–Randy