Model Railroad Sound Cams
We are the number one manufacturer of Sound Cams for Model Railroad sound in the world. Our cams work perfectly with through the rail style sound (GME, PFM, PBL) and with DCC and onboard sound systems.
Many manufacturers, such as Precision Scale Co., Mountain Model Imports, Berlyn Locomotive Works and others, install our cams at the factory.
We make several styles of cams for almost any application. The really nice feature of all of our cams is you do not have to remove a wheel from the axle to install it. All of our cams are designed to simply slip over the axle. They are glued in place using a 5 minute style epoxy. When the cam needs to be conductive to the axle, you use a conductive paint like the ones used to repair a rear window defogger grid on an automobile. It is available most auto parts stores.
We have several styles of cams. The ones most often used are the slotted and the split type. (photo of cams) (photo of cam installed on axle)
The cams we make and keep in stock are:
*** 4 point cams for a standard rod locomotive
*** 6, 8 and 12 point cams for use with geared locomotives. Shay, Climax and Heisler
*** 6 point for a 3 cylinder loco like the UP 9000
*** 8 point for an articulated loco. It gives you the offbeat " chuff, chuff" .
*** 2 and 3 point cams for use on the tender axle when needed.
All cams are available in many axle sizes. 2.0MM, 2.4MM, 2.5MM, 3.0MM, 3.5MM, 3.8MM, 4.0MM, 4.5MM, 5.0MM, 5.5MM, 5.8MM, 6.0MM, 8.0MM, 1/16", 3/32", 1/8', 3/16", 5/32" and 1/4".
If you happen to need a special size, special width, special diameter or special number of points on the cam, let us know and we will make it for you. Our cams are normally in 4 different diameters. .250", .310", .375" and .440". If you have a question about any of them, please email or give us a call.
INSTALLING THE G.M.E. SPLIT SOUND CAM
INSTALLATION
INSTALLING YOUR SOUND CAM IS VERY EASY BUT PLEASE DON’T GET IN A HURRY. READ THESE INSTRUCTIONS ALL THE WAY THROUGH BEFORE STARTING, THEN TAKE EACH STEP ONE BY ONE.
THE CAM WILL BE ATTACHED TO THE AXLE WITH AN ELECTRICALLY CONDUCTIVE EPOXY; WE HAVE DONE MANY OF THE INSTALLATIONS WITH THIS EPOXY AND HAVE BEEN 100% SATISFIED WITH THE RESULTS.
FIRST THING TO DO IS TO DETERMINE WHICH AXLE OF THE LOCOMOTIVE THAT YOU WANT THE CAM ON. SOME OF THE MOST RECENT BRASS MODELS COME WITH A CAM, USUALLY SQUARE (UNLESS IT IS A SHAY, HEISLER OR CLIMAX). (SEE FIG. 1) THIS TYPE OF CAM REQUIRES YOU TO LET THE WIPER HANG OUT IN THE AIR SO THAT ONLY THE TIPS OF THE CAM TOUCH. THEY DO WORK, BUT ARE SOMETIMES HARD TO ADJUST AND NOT AS EFFICIENT AS A ROUND CAM.
IF YOU HAVE ONE OF THESE ON THE AXLE, SIMPLY REMOVE THE WHEEL/AXLE ASSY AND CUT THE CAM OFF WITH A CUTTING DISK. (SEE FIG. 2)
NOTE:
REMOVE THAT WHEELSET ONLY. TAKE THE SCREWS OUT OF THE SIDE RODS (IF APPLICABLE) AND LEAVE EVERYTHING INTACT SO YOU CAN PUT IT BACK TOGETHER EXACTLY. IF YOUR ENGINE RUNS GOOD, DON’T TAKE THE CHANCE OF CROSSING SIDE RODS FROM SIDE TO SIDE. IT SHOULDN’T, BUT SOMETIMES IT MAKES A DIFFERENCE, ESPECIALLY IN STANDARD ROD LOCOMOTIVES. WHEN INSTALLING A CAM ON A SHAY, HEISLER OR CLIMAX LOCOMOTIVE, YOU MAY NOT HAVE TO REMOVE THE WHEELSET FROM THE TRUCK. SIMPLY REMOVING THE TRUCK FROM THE LOCOMOTIVE SHOULD GIVE YOU PLENTY OF ROOM TO INSTALL THE CAM.
WHEN REMOVING THE OLD CAM, CUT ALL THE WAY DOWN TO THE AXLE ON ONE SIDE THEN DO THE OTHER SIDE. BE CAREFUL NOT TO CUT INTO THE AXLE TOO MUCH. AVOID CUTTING THE AXLE AT ALL IF POSSIBLE. IF YOU DO CUT OR SCAR THE AXLE, IT IS OK, THE G.M.E. CAM WILL STILL FIT AND WORK PERFECTLY. JUST MAKE SURE YOU SMOOTH UP THE AXLE WITH A SMALL FILE BEFORE INSTALLING THE CAM.
IF THERE IS NO EXISTING CAM, YOU MUST CHOOSE WHICH AXLE TO INSTALL THE CAM. WHEN USING THE SIX, EIGHT AND TWELVE POINT CAMS, IT SHOULD BE EASY TO CHOOSE ONE. TRY TO CHOOSE ONE FOR EASE OF INSTALLATION OF THE WIPER ALONG WITH THE CAM. LOOK CAREFULLY AND PLAN THE INSTALLATION BEFORE YOU START. YOU WANT THIS INSTALLATION TO BE EASY AND PERFECT.
NOW THAT YOU HAVE CHOSEN THE AXLE FOR THE CAM, REMOVE THAT WHEELSET OR TRUCK ASSY. WITH A PIECE OF “FINE” EMORY CLOTH OR 600 GRIT SANDPAPER, CLEAN THE AXLE WHERE THE CAM IS GOING TO BE INSTALLED. WHEN GLUING THE CAM ON, YOU WANT THE AXLE TO BE VERY CLEAN.
THE ALIGNMENT MARKS
LOCATE THE ALIGNMENT MARKS ON THE CAM. (SEE FIG. 5) THEY ARE VERY SMALL AND MUST BE TOGETHER WHEN THE CAM IS INSTALLED. IF THEY ARE NOT CORRECTLY ALIGNED, THE CHUFF OF THE CAM WILL BE INCORRECT!!!!!!!!
GLUING THE CAM
WHEN GLUING THE CAM ON, PUT A SMALL AMOUNT OF ELECTRICALLY CONDUCTIVE EPOXY ON THE AXLE AND PUSH THE CAM ON THE AXLE. BE VERY CAREFUL NOT TO USE TOO MUCH OF THE EPOXY. IF THE EPOXY SHOULD FILL THE GAP COMPLETELY AND SQUEEZE OUT OF THE SEAMS WHERE THE CAM IS PUT TOGETHER, IT COULD ADD AN ADDITIONAL CHUFF WHERE THE SEAMS ARE. YOU WANT JUST ENOUGH TO FILL IN AROUND THE AXLE. IF SOME DOES COME UP THE SEAMS, DON’T WORRY ABOUT IT, WE WILL DISCUSS LATER HOW TO EASILY CORRECT IT. WHEN INSTALLING THE CAM ON A ROD LOCOMOTIVE LIKE A HEISLER, ALIGN ONE OF THE CAM CONTACT POINTS SO THAT IT IS ALIGNED WITH THE CRANK PIN. (SEE FIG.3) ON A SHAY LOCOMOTIVE IT IS NOT CRITICAL. IT CHUFFS SO FAST THAT YOU CAN’T NOTICE THAT IT IS NOT IN PERFECT SYNC WITH THE CRANKSHAFT OF THE ENGINE. INSTALL THE CAM ON THE AXLE THAT YOU HAVE CHOSEN AND MAKE SURE IT IS PROPERLY SEATED ALL THE WAY DOWN. WE LIKE TO PUT A CLOTHESPIN OVER THE CAM TO HOLD IT TOGETHER WHILE THE EPOXY CURES. (SEE FIG. 4) PUT THE AXLE IN A SAFE PLACE WHERE NO ONE (EVEN CATS AND DOGS) WILL NOT TOUCH IT. LET THE EPOXY CURE COMPLETELY BEFORE MOVING ON TO THE NEXT STEP!!!
NOW THAT THE CAM IS INSTALLED, IT MAY BE NECESSARY TO REPAIR THE EPOXY WHERE THE SEAMS OF THE CAM ARE. IF SOME HAS CHIPPED OFF (SEE FIG. 5) SIMPLY USE SOME NON-CONDUCTIVE EPOXY TO REPAIR IT. (THE 5 MINUTE VARIETY WORKS GOOD AND FAST) IF YOU HAD TO MAKE A REPAIR, LET THE EPOXY CURE COMPLETELY BEFORE MOVING ON TO THE NEXT STEP!!!
IF YOU MADE A REPAIR, CAREFULLY FILE OR USE AN EMORY BOARD TO ROUND AND SMOOTH THE REPAIR. TRY TO KEEP IT AS ROUND AS POSSIBLE. DON’T GO CRAZY WITH THE FILE! MAKE SURE THAT YOU GET THE CAM FAIRLY SMOOTH AND THAT ALL OF THE CONTACT POINTS ARE CLEAN OF THE EPOXY. A FINAL POLISHING OF THE CAM WITH SOME 600 GRIT SANDPAPER WILL MAKE THE CONTACT POINTS SMOOTH. REINSTALL THE WHEELSET AND YOU ARE READY TO TEST THE CAM INSTALLATION.
WHEN INSTALLING THE WIPER, USE SOME PRESSURE AGAINST THE CAM BUT NOT TOO MUCH. YOU WANT ENOUGH PRESSURE TO MAKE GOOD CONTACT BUT NOT ENOUGH TO DAMAGE THE CAM OR THE WIPER. ALSO, THE CAM COULD HAVE SOME AMOUNT OF WOBBLE OR UP AND DOWN HOP TO IT IF IT MOVED DURING THE INSTALLATION PROCESS. DON’T WORRY ABOUT IT, IT WILL PROBABLY WORK FINE. INSTALL THE WIPER AND THE CHUFF CAPACITOR AND TRY IT. IF YOU GOT ALL THE EPOXY OFF THE CONTACT POINTS AND SMOOTHED THEM UP IT SHOULD WORK PERFECTLY, WOBBLE OR NOT.
IF YOU GET AN EXTRA CHUFF BEAT WHEN RUNNING THE LOCOMOTIVE, IT IS POSSIBLE THAT THE ELECTRICALLY CONDUCTIVE EPOXY CAME UP THE SEAMS OF THE CAM AND IS PROVIDING AN ADDITIONAL ELECTRICAL PATH FOR THE WIPER. THIS IS VERY SIMPLE TO REPAIR. AGAIN REMOVE THE AXLE FROM THE LOCOMOTIVE AND WITH YOU MODELER’S KNIFE; CUT OUT THE EPOXY AS SHOWN IN THE AREA OF THE SEAMS. (SEE FIG. 6) MIX SOME OF THE NON-CONDUCTIVE EPOXY AND FILL THE GAPS THAT YOU CUT OUT. AFTER THE EPOXY HAS COMPLETELY CURED, REROUND THE CAM, SLIGHTLY POLISH IT WITH SOME 600 GRIT SANDPAPER AND REINSTALL THE WHEELSET, THE EXTRA CHUFFS SHOULD BE GONE.
AS ALWAYS, WE WELCOME YOUR COMMENTS AND SUGGESTIONS ON THIS INSTALLATION. IF YOU HAVE ANY IDEAS ON HOW TO IMPROVE OUR PRODUCTS OR JUST A SUGGESTION OF A PRODUCT YOU WOULD LIKE TO SEE US PRODUCE, CALL, WRITE OR E-MAIL US. WE LOOK FORWARD TO HEARING FROM YOU.
INSTALLING THE G.M.E. SOUND WIPER MOUNT
Installing the G.M.E. SOUND WIPER MOUNT is relatively simple. The unit is stacked together as shown in (Figure 1). The only trick is to determine where the unit will be installed. In most cases we have installed them as shown in (Figure 2a). We drill and tap a OO-90 hole in the bottom retainer plate and simply tighten the assembly down. After adjusting the wiper to lightly ride on the cam, it works perfectly. (Make sure that you solder your wire or chuff capacitor to the wiper before installation. Trying to solder it after installation will melt and destroy the washer and spool.)
(Figure 2b) shows another method we have used to install the unit. By mounting the wiper holder to the motor support, we are able to bend the wiper vertical to contact the cam. When mounting the unit farther to the back, the wiper can be left horizontal. These methods work extremely well and because they are up inside the frame, it hides the wiper holder.
Another method we use is to solder your wire to the wiper then stack the unit together with a small amount of five minute epoxy. After the epoxy is cured, you have a single unit and easier to install.