|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
09-08-2019, 08:56 PM | #21 | |
Senior Member
Join Date: Apr 2012
Posts: 1,542
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Quote:
|
|
09-09-2019, 04:38 AM | #22 |
Senior Member
Join Date: May 2010
Location: VA
Posts: 1,410
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
See https://www.tibtech.com/conductivite.php?lang=en_US
Copper is almost ten times as conductive as steel. The steel frame makes up for it by being more than ten times the cross sectional area. |
Sponsored Links (Register now to hide all advertisements) |
|
09-09-2019, 05:03 AM | #23 | |
Member
Join Date: Jul 2019
Location: Central New Mexico
Posts: 83
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Quote:
Sent from my E6810 using Tapatalk |
|
09-11-2019, 11:59 AM | #24 |
Senior Member
Join Date: Jul 2019
Location: Oklahoma City, OK
Posts: 184
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
When I was young, 14 or so, I pee'd on an electric fence wire which was surounding our horse lot. It was steel wire, and conducted electricity quite well. Will never foget it.
|
09-11-2019, 12:13 PM | #25 |
Senior Member
Join Date: Apr 2018
Location: Mebane NC
Posts: 2,353
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Comparison of square cross-sections of materials having the same conductivity (measured in IACS)
|
09-12-2019, 07:08 AM | #26 |
Senior Member
Join Date: May 2010
Location: South East NJ
Posts: 3,398
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Sponsored Links (Register now to hide all advertisements)
With the A it is not the iron that is a problem. It is in understanding the ground paths as they are complicated. When we restore the car we do a lot to cover what would be the ground paths. So from the engine to the frame you travel from the driveline up through the springs (spring bolts to be exact) to the frame as one major path. You also have the often not installed engine shields. Of course you have to be sure that the various bolts have bit though the paint to make a path. So in restoring my car. I tinned the area where the pos strap attached to the frame and then put tape on the area so no paint is put there. I made grounding contact paths from the frame through the fender brackets into the headlamp bar and put tape in the sockets for the headlamps before paint. If you used a thicker paint on some areas then you need to be extra certain the lock washers cut through or maybe cut through the paint first. A little extra care goes a long way to a more reliable car. |
09-12-2019, 08:07 AM | #27 |
Senior Member
Join Date: Aug 2019
Location: Hagerstown MD
Posts: 224
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Ditto what Kevin said, electrical current travels on the surface of the conductor. There's a bunch of different paths for the current to get from the engine to the frame and battery but a heavy gauge ground strap does it best.
|
09-12-2019, 08:15 AM | #28 | |
Senior Member
Join Date: Apr 2012
Posts: 1,542
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Quote:
Kevin sounds like you have the best-grounded Model "A" in America JK. More seriously, I think it is acknowledged that the Model "A" frame, as it came from the factory, did not really have much of a paint job on it, surely not the thick glossy enamel we like to use. |
|
09-12-2019, 08:37 AM | #29 |
Senior Member
Join Date: May 2010
Location: Bucks Co, Pa
Posts: 3,740
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Auxillarily grounds can make a surprising difference in the amount of power that gets to the starter. I was always hearing "Ya need an 8 volt battery!" No, I needed a good ground! I put a second ground on it. The old ground cable bolted to the top flange of the frame. Using the same bolt, only the underside. I changed the bolt to a 3/8 brass and ran the cable to one of the starter bolts. The starter spun over with new life, who needs 8v or 12v for that matter. We generally can't get to the ground paths and they've been rusting away for 90 years. Naturally they slowed the current down somewhat.
Terry |
09-12-2019, 08:39 AM | #30 |
BANNED
Join Date: Apr 2017
Location: Sacramento
Posts: 1,262
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
the engine pans were the ground path to the engine/driveline.
|
09-12-2019, 09:00 AM | #31 | |
Senior Member
Join Date: Apr 2013
Location: Northwest CT
Posts: 1,092
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
Quote:
My car has the main ground cable running right from the battery to the top starter bolt. A 7 year old neglected 6V battery still spins it over like it was new. I use the stock ground on the frame for an auxiliary ground. |
|
09-13-2019, 10:19 AM | #32 |
Senior Member
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 16,426
|
Re: Stupid Question #2: how does an iron frame act as a ground on our cars
The skin effect only applies to alternating current. Direct current flows equally through a conductor. This is why DC is used a lot for magnetizing ferromagnetic objects for magnaflux inspection and for welding.
|
|
|
Sponsored Links (Register now to hide all advertisements) |
|