Anywhere to get mth spst mini slide switch in bulk?

Paging Gunrunner John......

Go to ebay and type in "miniature slide switch". Then take your pick.

Pete

It's pretty easy to find a switch the right size, the complex part is finding a switch that is threaded so you don't have to fool around with the tiny nuts.

I've truthfully not purchased these switches separately.  I do a lot of ERR and PS2 upgrades, and I end up with tons of the proper sized little switches.  The ERR switches require the small nuts, so they're not as convenient as the ones Lionel uses.

Note that MTH has two sizes of switches, they have a larger DPDT switch that is sometimes used.  I keep those for 2-rail conversion polarity reversal switches.  I have bought some of those from MTH when I get low on them.

I did a search on Lionel parts and found 6253664303 which costs a dollar. This switch is common to many locomotives. I don't see any nuts, and the screw looks to be somewhat like self tapping. I always thought the switches had a size hole that got tapped when you first put in the screw.

The screws are 6104589533 and .30 each.

I also have some Lionel switches, black, and may have threads 620 8215 303 and are also a dollar.

You can certainly get matching screws for a lot less than 30 cents each, but the switch has a machine tapped thread when you get them.  I have had a couple of new ones that came that way.

Yes I just found some that look to be tapped.

620 8215 303

In order to purchase aftermarket switches, you would need to take careful measurements of an original switch, including length, width, as well as the location and size of the mounting holes. Perhaps the thickness too.

When I wanted some slide switches for Lionel, I ended up getting them as Lionel parts on Ebay. Someone was clearing out old service station inventory.

Another point that you have to consider is the height of the switch handle.  I have switches that have three different height handles, they all mount on the same centers, some are designed for thick diecast frames, others are for the stamped steel frames.