Condenser question for pstephens46

[ausnoelm]

Once you start filing points they are shot, you will have to keep filing them because they have shiny hardened face when new, but after filing, the surface is removed and will need constant attention.

[boscoe99]

VW with about 70hp?
Hot azz engine in back during summer, fumes etc. Don’t miss that a bit. Although I think it would be cool to have one of those Kubelwagen convertible things. Called the Thing and sold in the US after WW II.

I was thinking it was about 45 HP. Load that thing up, go up a hill and you were in second, if not first, gear all the way.

[99yam40]

when the condenser was not doing it's job to protect the points, it needed to be changed along with the points.
I have a feeling the caps back then did not hold up well in those hot engine compartments.

the electronic ignition replacements did wonders to extend tune up intravels along with the higher voltage coils

[rodbolt17]

a condenser/capacitor blocks AC and stores/discharges DC.
if you ever looked at the old point ign coil primary with a scope you will note a few things.
one is coil primary voltage peaks at near 200V when the secondary collapses.
second thing you will note is the ign coil does NOT completely discharge with the first collapse but will discharge 6-10 times depending on the coil.
technically it is a DC voltage but the rapid spiking makes it look electrically like A/C..
the condenser simply acted as a rapidly charging battery and when the points closed it discharged that 200 or so voltage that was stored.
this stuff was taught at Hogan High in Vallejo CA back in the 70's.
I was the first Freshman ever to be allowed to take the vocational course without taking the basic course.
had to take one of Mr Mortons nasty tests but I passed it and he told the Dean he would accept me.
my jr and senior years I did 2 vocational classes in the AM,was the teachers assistant for 6th period and was an assistant for the Wednesday night adult automotive course.
I graduated in 1980.
who remembers the old ratheon cathode ray scopes and distributor testers and voltage regulator adjustments.
does anyone remember how to poerize a generator regulator when one of the components got replaced?

[99yam40]

Yes I remember most of that, but have killed a couple of those brain storage cells over the years.
I do not remember having to polarize an automotive generator
I was in the 71 grad class. All I had to take in senior years was 4th year of English the rest were electives
Junior and senior years I was in Automotive vocational .
1st years they had them in my HS.
went to TSTI in waco after HS.
worked as a mechanic for some years before My brother and Uncle convinced me to become an Electrician in a large Chemical Plant here on the Tx coast

[zenoahphobic]

I like Rodbolt's explanation that the condenser was part of the system as a "rapidly charging battery " to deal with that high voltage that developes (ringing) in the primary winding. It's good side affect was that it slowed down the burning of the points.
Like many things, an example where things are incorrectly referred to. It however explained to me why I had increased reliability (of this Kettering system, that no one seems to refer to as) by defying manufacturer's gap specification and setting to a much smaller gap. This smaller gap meant less destructive voltage arced across the points, and therefore they lasted longer
I think I hated points from the first day I learnt that they existed. When I learnt a bit of electronics I attempted to change every engine I owned (built CDI and used Transitors as the switch, and even used photo transistors and hall affect transistors for the timing; all back in the early 70's).
Those early days there was strong resistance to using electronics in automobiles. Those "dinosaurs " that felt there was no place for electronics (like those against plastics) will be turning in their graves if they could see the dominance electronics has now.

[99yam40]

It was and still is my thoughts that without a large enough gap the DC arc would continue longer.
the condenser helped with not having a extremely large gap.
the points do open and close DC after all,
but I agree they also have to deal with the spikes associated with the collapsing fields(ringing) in the coil also

In a lot of DC systems we used multiple contacts in series to get a large enough gap(added together) to extinguish the arc when opening the contacts to keep them from burning up. ( 28,48, & 125VDC control systems)

[pstephens46]

It was and still is my thoughts that without a large enough gap the DC arc would continue longer.
the condenser helped with not having a extremely large gap.
the points do open and close DC after all,
but I agree they also have to deal with the spikes associated with the collapsing fields(ringing) in the coil also

In a lot of DC systems we used multiple contacts in series to get a large enough gap(added together) to extinguish the arc when opening the contacts to keep them from burning up. ( 28,48, & 125VDC control systems)

You could have gotten some weekend work too!

[boscoe99]

Electricity when flowing across the points wants to continue flowing as the points open. Instead of trying to flow through the points as they are just beginning to open electricity can flow into the condenser. It takes the path of least resistance. At the point where the condenser is fully charged and current stops flowing into it, the points should be opened sufficiently that the gap is too large for current to jump across them.

In theory anyway.

[99yam40]

the plant operators did call me sparky and lightning some times. But that was because i took some relatively high voltage hand to hand and came back to work the next day after they let me out of the hospital.
they just held me over night monitoring me to see if my heart was going to stop.

all of those years as an electrician and I did not know after taking voltage like that the heart could stop up to 8 hours after.

[99yam40]

Electricity when flowing across the points wants to continue flowing as the points open. Instead of trying to flow through the points as they are just beginning to open electricity can flow into the condenser. It takes the path of least resistance. At the point where the condenser is fully charged and current stops flowing into it, the points should be opened sufficiently that the gap is too large for current to jump across them.

In theory anyway.

DC is worse since it does not go back thru zero 60 times a second like AC does.
You can weld with the DC from batteries

[ausnoelm]

If you can get the same current as a car battery, you can and do weld with AC as well, it has nothing to do with going back to 0, try welding with a few flashlight batteries.

[walleye1]

Macgyver did.

[99yam40]

If you can get the same current as a car battery, you can and do weld with AC as well, it has nothing to do with going back to 0, try welding with a few flashlight batteries.

Ac is less hard on contacts since when it goes thru the zero voltage in the sine wave the current drops to zero also with the contacts open and the arc goes away

[zenoahphobic]

It hasn't been raised above, but to make the description of the old points system more balanced it needs to be added that the actual points gap provides the necessary timing to allow the coil to fully "discharge" so that it can have it's full capacity back to enable it to produce it's next (strong) spark in the time frame required. The actual points gap was not chosen to stop arching.
You mechanics have your way of describing things and there tends to be a habit to only concentrate on one aspect of the system. As already implied the points system, described above as made up of only 3 components, was problematic and people have had various hates with it.
A simple system yet complex because it required to produce a strong and reliable spark both for starting (slow RPM) and at high rpm and full fuel/air mixture, each component very crucial and the slightest degradation of each often having significant affect. The series resistor when starting attests to the fact those coils had very limited operating range.