Skip to main content

Good evening all,

I’m currently doing a proto 3 conversion on a proto sound 4-6-2 locomotive and everything is done, but there is one small problem.  Literally… the flywheel for this loco is tiny.  I used the smallest tach tape that came with the conversion kit and the speed of the locomotive does not match what the DCS speed says.  At 1 MPH it is actually running about 10MPH.  The tach reader is at the correct distance from the flywheel.  Is there any other different tape I could use to slow down the loco and make the speed match the DCS speed?  Due to the frame size I’m unable to place a larger flywheel on this motor.

thank you all in advance!


Original Post

Replies sorted oldest to newest

You want to end up with 24 evenly spaced lines. 24 is the key to get speed matching when installing the sound file for that particular locomotive. I think John Will, aka gunrunner has posted a pdf of different size tach tapes. I made my own with by scanning the tach tapes supplied with the upgrade kit, then changing the size sent to my printer using the scale feature in the print menu until I had a strip that matched the circumference of the flywheel. 24 lines plus 24 spaces equal the circumference.


Rick, I printed the tape on mailing label. First scanned the tapes MTH provides with their upgrade kit and then printed a smaller image using the reduction feature in the print menu. John’s pdf should have the correct size as there are dozens there.

The pdf images are in this thread. John’s first post is simply a copy of the tapes in the kit but his second post has a series of pdfs. Since there will be some difference in lengths due to the resolution of your printer, one listed slightly shorter or longer may actually be the correct size for that flywheel.


Last edited by Norton

I print on half-page mailing labels, I've done tapes down to around a 20mm flywheel and had no issues with operation.  Here's a set of graduated tach tape images and a nice page about making custom tach tapes by the Hikel boys.  I thought I posted these in one of the documentation threads, but I couldn't find them.

If you have a compatible gear ratio, just measure the circumference of the flywheel and match it up to one of the custom tapes to get 24 stripes.  You can also print the labels on plain paper and do "trial fits" of the flywheel if that works for you.

Custom Tach Strips for


I moved this topic to the correct forum.  This is a question above a proto-3 problem NOT a 3-rail scale topic!  Those of you responding, please help us by alerting us when you see topics in the wrong forum.  By placing topics in the wrong forum, it makes it that much more difficult for others searching for help.


Add Reply

The DCS Forum is sponsored by
OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
Link copied to your clipboard.