The Ford Barn

mshmodela · 11-22-2015, 06:10 PM

Here's a short video the the innards of my repo ammeter...

https://www.youtube.com/watch?v=OtRiZf_gV2Y

2935ford · 11-22-2015, 06:21 PM

The back of the one like yours we have melted those plastic connectors!
Be careful.

I try to find originals.

mshmodela · 11-22-2015, 06:29 PM

Yeah, I think this is of very poor quality. In fact I took it apart as the needle felt off...

MikeK · 11-22-2015, 09:12 PM

The original wasn't much to write home about, either! Yes the needle stayed on but the entire design was based on differential magnetic induction. That made it real cheap to manufacture but has many drawbacks such as: accuracy +or-5% if your lucky when new, +or-10~20% a year later; directionally affected by the earths mag field and nearby ferrous objects; no damping, much needle bouncing while driving. Yes, that is the original.

The reproductions all follow the same sloppy, inaccurate differential magnetic induction design. A replacement meter with a quality D'arsonval shunt current movement would fix all those problems but would double the cost.

Y-Blockhead · 11-23-2015, 12:51 AM

Quote:

Originally Posted by MikeK

A replacement meter with a quality D'arsonval shunt current movement would fix all those problems but would double the cost.

I'd gladly pay double...

What would that be ~$13 for a good meter??

mshmodela · 11-23-2015, 08:15 AM

Sponsored Links (Register now to hide all advertisements)

I'd pay $50 for one that would last 10 years....

Skeezixx · 11-23-2015, 09:36 AM

My original spontaneously caught on fire one day.

Sounded like Jolsen begging for a spare dime in the background.

Richard Lorenz · 11-23-2015, 09:53 AM

The 2 tabs on the bottom can be bent to partially correct any error in the reading.

mshmodela · 11-23-2015, 10:21 AM

Quote:

Originally Posted by Skeezixx

My original spontaneously caught on fire one day.

Sounded like Jolsen begging for a spare dime in the background.

Correct...

11-22-2015, 06:10 PM	#1
mshmodela Senior Member Join Date: Mar 2014 Location: Cleveland, Ohio Posts: 2,763	Repo Ammeter Innards Here's a short video the the innards of my repo ammeter... https://www.youtube.com/watch?v=OtRiZf_gV2Y __________________ -Mike Late 31' Ford Model A Tudor, Miss Daisy I don't work on cars --I'm learning about my Model A. Cleveland, Ohio

11-22-2015, 06:21 PM	#2
2935ford Senior Member Join Date: Mar 2011 Location: New Brunswick, Canada Posts: 1,013	Re: Repo Ammeter Innards The back of the one like yours we have melted those plastic connectors! Be careful. I try to find originals.

11-22-2015, 06:29 PM	#3
mshmodela Senior Member Join Date: Mar 2014 Location: Cleveland, Ohio Posts: 2,763	Re: Repo Ammeter Innards Yeah, I think this is of very poor quality. In fact I took it apart as the needle felt off... __________________ -Mike Late 31' Ford Model A Tudor, Miss Daisy I don't work on cars --I'm learning about my Model A. Cleveland, Ohio

11-22-2015, 09:12 PM	#4
MikeK Senior Member Join Date: May 2010 Location: Windy City Posts: 2,919	Re: Repo Ammeter Innards The original wasn't much to write home about, either! Yes the needle stayed on but the entire design was based on differential magnetic induction. That made it real cheap to manufacture but has many drawbacks such as: accuracy +or-5% if your lucky when new, +or-10~20% a year later; directionally affected by the earths mag field and nearby ferrous objects; no damping, much needle bouncing while driving. Yes, that is the original. The reproductions all follow the same sloppy, inaccurate differential magnetic induction design. A replacement meter with a quality D'arsonval shunt current movement would fix all those problems but would double the cost.

11-23-2015, 08:15 AM	#6
mshmodela Senior Member Join Date: Mar 2014 Location: Cleveland, Ohio Posts: 2,763	Re: Repo Ammeter Innards Sponsored Links (Register now to hide all advertisements) I'd pay $50 for one that would last 10 years.... __________________ -Mike Late 31' Ford Model A Tudor, Miss Daisy I don't work on cars --I'm learning about my Model A. Cleveland, Ohio

11-23-2015, 09:36 AM	#7
Skeezixx Senior Member Join Date: Jul 2010 Posts: 426	Re: Repo Ammeter Innards My original spontaneously caught on fire one day. Sounded like Jolsen begging for a spare dime in the background.

11-23-2015, 09:53 AM	#8
Richard Lorenz Senior Member Join Date: May 2010 Posts: 447	Re: Repo Ammeter Innards The 2 tabs on the bottom can be bent to partially correct any error in the reading.