Jump to content




Photo

Tradeship slot car motor tachometer


  • Please log in to reply
9 replies to this topic

#1 tlbrace

tlbrace

    Mid-Pack Racer

  • Full Member
  • PipPipPip
  • 146 posts
  • Joined: 11-August 11
  • Gender:Male
  • Location:USA

Posted 06 August 2016 - 12:08 PM

So I picked up what appears to be an unused vintage Tradeship slot car motor tach. In its box, but no instructions.

 

I have no idea if, when sold back in the day, these were accurate.

 

Anybody have any idea how these are used? Better yet if anyone has instructions to scan and send, so much the better!

 

Thanks!

 

T

 

rev 1.jpg

 

rev2.jpg


Todd Brace




#2 Cheater

Cheater

    Headmaster of the asylum

  • Root Admin
  • PipPipPipPipPipPipPipPip
  • 21,350 posts
  • Joined: 14-February 06
  • Gender:Male
  • Location:Norcross, GA

Posted 06 August 2016 - 01:44 PM

Neat snag, Todd. 

You might take a variable speed drill (a small Dermel would be ideal), chuck an appropriate shaft in it to connect to what looks to be a spring connector on the tach, and see what you get when you spin it up carefully.

 

Just for curiosity's sake, where did you stumble on this? eBay or somewhere else?


Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#3 Mattb

Mattb

    Race Leader

  • Subscriber
  • PipPipPipPipPip
  • 761 posts
  • Joined: 13-August 11
  • Gender:Male
  • Location:IN

Posted 06 August 2016 - 02:13 PM

I wonder how many the guy has. I have seen them on eBay for a couple weeks.

 

I wondered if it is designed for a big open pole motor and used a rubber band to drive the shaft and measure RPM.


Matt Bishop

Vintage Cox Slot Cars

#4 Cheater

Cheater

    Headmaster of the asylum

  • Root Admin
  • PipPipPipPipPipPipPipPip
  • 21,350 posts
  • Joined: 14-February 06
  • Gender:Male
  • Location:Norcross, GA

Posted 06 August 2016 - 02:49 PM

Thanks for answering my question to Todd, Matt.

 

Here's a better pic of the 'face' from one of the three or so sold listings I spotted.

 

tach.jpg

 

One hopes that the markings have a multiplier (i.e. 3,000 = 30,000) or its not going to be a very useful device with any current motor.

 

 


Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#5 Guillermo Suar

Guillermo Suar

    On The Lead Lap

  • Full Member
  • PipPipPipPip
  • 265 posts
  • Joined: 03-September 08
  • Gender:Male
  • Location:Mount Vernon, IN

Posted 06 August 2016 - 06:29 PM

I guess it's like an old car speedometer. A magnet spins inside a metal can and creates a torque by means of Eddy currents. A spiral springs counterbalances the torque created. The higher the RPMs the higher the torque and the needle deflection.

 

I doubt it would have any kind of means of changing the range. 


Because light travels faster than sound, some people appear to be bright until we hear them speaking.

#6 88honcho

88honcho

    Rookie Keyboard Racer

  • Full Member
  • Pip
  • 46 posts
  • Joined: 16-October 11
  • Gender:Male
  • Location:NJ

Posted 06 August 2016 - 11:33 PM

It attaches directly to the motor shaft. They came with two spring couplers, one for .091" and one for .078".  

 

Set the dial to 'red line' which is zero.

Run motor for exactly 60 seconds.

Count the number of times the pointer goes around (clockwise only) past 'red line' in the exactly 60 seconds.

Multiply by 3,000.

Add the number shown by the pointer on the dial to the total.

 

The sum of the total of the 3000s counted plus the number it stopped at after exactly 60 seconds is "the revs."

 

Example: Pointer passes zero 10 times in 60 seconds and then stops at 2250. The RPM rating is 32,250.

 

That's it! 


  • Cheater, Half Fast and Samiam like this
Nicholas Killmer

#7 tlbrace

tlbrace

    Mid-Pack Racer

  • Full Member
  • PipPipPip
  • 146 posts
  • Joined: 11-August 11
  • Gender:Male
  • Location:USA

Posted 07 August 2016 - 07:20 AM

Thanks! This did indeed come with the couplers.


Todd Brace

#8 Cheater

Cheater

    Headmaster of the asylum

  • Root Admin
  • PipPipPipPipPipPipPipPip
  • 21,350 posts
  • Joined: 14-February 06
  • Gender:Male
  • Location:Norcross, GA

Posted 07 August 2016 - 09:00 AM

I guess it's like an old car speedometer.


Based on 88honcho's post, this is not so much a tach as a revolution counter, so it must be simply a reduction gear train. Counting the number of revs in 60 secs (a minute of course) gives RPM.


Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#9 Mattb

Mattb

    Race Leader

  • Subscriber
  • PipPipPipPipPip
  • 761 posts
  • Joined: 13-August 11
  • Gender:Male
  • Location:IN

Posted 07 August 2016 - 11:35 AM

Too complicated for me, but at least we found out how it works!
Matt Bishop

Vintage Cox Slot Cars

#10 Samiam

Samiam

    Posting Leader

  • Subscriber
  • PipPipPipPipPipPipPip
  • 3,619 posts
  • Joined: 18-January 12
  • Gender:Male
  • Location:Long Island, NY

Posted 07 August 2016 - 06:41 PM

It attaches directly to the motor shaft. They came with two spring couplers, one for .091" and one for .078".  

 

Set the dial to 'red line' which is zero.

Run motor for exactly 60 seconds.

Count the number of times the pointer goes around (clockwise only) past 'red line' in the exactly 60 seconds.

Multiply by 3,000.

Add the number shown by the pointer on the dial to the total.

 

The sum of the total of the 3000s counted plus the number it stopped at after exactly 60 seconds is "the revs."

 

Example: Pointer passes zero 10 times in 60 seconds and then stops at 2250. The RPM rating is 32,250.

 

That's it! 

 

Good thing there are still a few guys out there that can pull this kind of information out of their @%$ and post here.

Thanks Nicholas :victory:


  • Cheater likes this
Sam Levitch
 
When the only tool you have is a hammer, everything is a nail.
Support your local raceway, or you won't have one.
Slot cars are quad-pods.
Support your "Local Racer."
:laugh2:





Electric Dreams Online Shop