Some one a while back stated they used a motor driven coil test unit. I am going to do this with my homebuilt HCCT and was wanting to know the RPM it should be set up to run. Thanks for any help. KGB
Luke Cordes with Space City T's has had one for a long time. He put on a program with it at our meeting several years ago. He checked some brass tops of mine at the meeting. He monitors the forum so since caps are for shouting,
Ken in Texas
Here's an older thread with some discussion on what speed to crank/spin the tester: http://www.mtfca.com/discus/messages/29/25062.html?1172845899
And here is some more: http://www.mtfca.com/discus/messages/80257/81960.html?1235175846
100 rpm would probably be fine. Be aware of all the heavy spinning stuff, some kind of belt & flywheel guard might be needed if you have visitors in the garage.
Tough on start-up. A lot of mass to get moving.
The question for you would be; What is the output of your tester mag ring at say 60 RPM? You'll want at least 2-3 volts. If the magnets on your tester are weak, you may need a higher RPM.
Adding: That's 2-3 volts with a load! (Same as in-car mag testing.)
Ken Parker like a lot of us is getting old. That Variable speed motor driven coil tester was built by me and I had it at the Space City meeting. Luke is my son and he likes distributors more than coils. It uses a real flywheel and mag ring and also a brake drum for a spark rack.
It is variable, but I usually run it near 300 RPM. I have a "Magnetic pick-up device" on the teeth of the flywheel which goes to the RPM gauge. I think I calibrated it correct based on the number of teeth on the flywheel.
It also has a volt meter and an amp gauge.
I welded up a frame and built it out of surplus transmission parts and a surplus variable speed motor from work. IF I had young kids around, I would build a cover of some sort.
Willie, that's the info I was looking for and I thank you! KGB
First of all, think of Ford ignition coils as AMPERAGE units, not voltage.
In the car, each coil will fire according to the firing order every two revolutions,,,, and is "governed" by the timer on the camshaft.
On the HCCT, the tested coil will fire every time a magnet passes a field coil.... that's 16 firings every revolution of the flywheel.
At 60 rpm's, times 16 coil firings, how many times will that coil fire in that minute ???? You do the math.
Eventually, with added rpm's of the tester, the physical action of the points during testing will be overcome, the point action is compromised and erroneous meter and spark ring values will appear.
At tester speed of 60 rpm's or so with the coils sparking 16 times per revolution, coils calibrated a 1.3 amp draw, single spark on tester, ..... is roughly equivalent of the Model T car running near 45 MPH.
So why defeat the tester results at 60 rpm's ???
Remember, Ford ignition coils are tuned for amperage, not voltage....
KGB, 60 RPM may be correct for a HCCT. I can not imagine the true hand turned model being turned at 300 RPM.
I got a feeling that I miscalibrated that tach years ago when I installed it. I looked for my hand held tach, but I did not find it to check the RPM.
I read some past postings by Ron Patterson and he seems to think about 60 RPM was correct.
My tester gets to about 7 volts at that 300 RPM reading on my tach and the spark is easy to see and if it double fires, that is also easy to see and I correct it on the points.
The coils work very well after I go thru them on my tester.
This does make me want to recheck that tach with a hand held tach even if coils work great after adjusting them.
Thanks guys, I believe you all are right about the 60 rpm's. I know the 1.3 amps is what to go for, I figure the main thing is a constant speed and having both hands free to do the adjusting. Besides I get winded pretty easy anymore turning the hand crank! KGB
Even though I set my coils with a strobo-spark I do have a couple of HCCT's and both of them will produce sparks at cranking speeds below 1 revolution per second (60 RPM). I think that if you need to crank it that fast or faster to get sparks then there is either something wrong with the coil adjustment or something wrong with the HCCT like weak magnets or too much gap between the magnets and mag ring coils. Of the 2 HCCT's I have, 1 was restored here (its an Allen) and the other by Ron Patterson - a double stack early one that my son Johnny has.
It would be nice to know what the RPM is of the original motor driven HCCT's.
Anyone have that info?
I am going to take a stab at part of this. If the motor was made for 60 cycle AC then the speed is 1425 RPM without any reduction, I think that has been the standard, even back then. From there you would need to find the pulley size for both the HCCT and motor. With a 14 inch pulley on the HCCT and a 2 inch on the motor that would still only bring you down to about 203 RPMS if I did the math right.
K.R. Wilson's motor driven testers were driven at 60 R.P.M's.
1425/1450/1500 is the speed on 50 hz motors. 60 hz motors are 1725/1750/1800. Not sure why the three different speeds, but you do see different motors rated at those different speeds. The middle one is what is most commonly seen. The higher one is probably just nominal, but seldom if ever achieved.
Lots of good information. I have a home built HCCT so am not concerned about the mag ring as I rewound it myself and recharged the magnets. I realize as John says that you don't have to crank very fast to get the required 1.3 amps. I am just trying to find the nominal rpm's to run it and I think several of you guys have given me the answer I needed. Thanks Herm for the pictures of the KRW, that gives me a good idea how to set it up. KGB
I was wrong, read the number without my glasses, should be 1725 on the two I went back and looked at.
The photos posted above by Herman Kohnke depict a Allen electric HCCT that has a motor adapted to rotate it.
Here is a photo of an original K.R. Wilson Model W-49 motorized HCCT.
Ron the Coilman
I have the motor driven unit , I can get fire at the plug by spinning it by hand,
other than that I have not played with it
what is the hammer (shown) for ?
For adjusting the lower points. In the photo is shows the hammer end being used, the wedge end is used to lift the points in the same area. This is how the AMP's are adjusted.
By the way, you have your spark plug sitting the wrong way in the photo, it should go the other direction. With it sitting that way, the electrons are going to fire the wrong way, it's going to un-fire.
Not to digress, motorized testers have their advantage. For the guy that is mechanical/electrical minded, the hand cranked coil tester will show the ramp time needed ( plus or minus ) at your controlled turning rpms before the tested coil starts to spark.... an added feature to dial in on the electrical calibration.
Has anyone found original printed matter that specifies the rpm's of a motorized coil tester ?
The one I have is almost exactly like the one that Royce posted. There is a groove machined into the flywheel for the belt, and the motor looks the same too, but I don't think the pulley on the motor is original. I've been using it for 40 years, and always works nicely.