[AT] Make repairs or payments

[Gene Dotson]

    The favored material for point contacts made in the 1950-1970 was 
tungsten. Tungsten is the material used in light bulbs. Good conductivity 
and resistant to burning and pitting. Tungsten during an inactive period 
developes tungsten oxide, a thin hard coating and nonconductive. They should 
be cleaned with a contact burnishing tool and not sand paper. This 
burnishing tool leaves a very fine smooth finish and removes very little of 
the parent contact material. Grant is right on the cheapening of the 
materials of both the contact and spring material.

                    Gene




-----Original Message----- 
From: Grant Brians
Sent: Tuesday, January 30, 2018 10:28 AM
To: at at lists.antique-tractor.com
Subject: Re: [AT] Make repairs or payments

When people talk about how "they don't make points like they used to",
there is a very specific reason for the comment. In the 1930's points
were sometimes still made with platinum contacts. They were not plated,
the contacts were actually a piece of platinum. This was true of
Studebakers at least. After the Platinum days, the contacts were still
made of unplated oxidation resistant pieces for the contact itself. Then
the switch was made to plated contact points and thinner and thinner
plating. While in some cases the plating material was substantially
superior in both burn and oxidation resistance, the issue has been that
the thin material can be consumed easier and that it cannot be touched
up by filing or scraping like the older contacts.
      The other factor I know I rarely think about is the "spring"
material. I recall in my first decade of working on motors (the 1970s in
my case), I saw thicker spring material in the points that I replaced
and also in the replacements I used than in recent times. In the days of
slow engines (our antique tractors for instance), the material needed to
flex less than it would on a faster motor. I cannot speak with any
authority on this, but I wonder if as thinner material has been used
could the resistance to breakage have been reduced? While Metallurgy has
dramatically improved since the 1930s, so has the pressure to use
cheaper and cheaper materials and amounts of material on low price
items. It would be logical that the spring steel in points would have
undergone "cost-saving modifications", especially since all of them are
in the cost competitive aftermarket for all of the items we work on.
                 Grant Brians - Hollister,California farmer of
vegetables, herbs, edible flowers, nuts and fruit

On 1/29/2018 8:29 PM, Ralph Goff wrote:
> On 1/29/2018 9:39 PM, Jason wrote:
>> They don't quite make points like they used to. Electronic is really a 
>> good
>> way to go.
> I really can't complain on the service I get from points and condensors.
> I really can't remember when I last put a set of points or condensor
> in the Cockshutt tractors. I think I replaced them in the IH Loadstar a
> few times in the 34 years I've driven it but its been a while.  The 52 
> Merc
> old flathead is running great on whatever points and condensor were in
> there when it was parked in the early 1980s. I did shine them up a bit
> to get it started the first time. I remember adjusting the points once
> on the Chevy II (six) and might have eventually replaced the points.
> On the other hand, I don't think I have spent anything on electronic
> ignition repairs on my GM engines in the 81 and 97 engines. So yes,
> electronic
> has been good to me too.
>
> Ralph in Sask.
>
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