Making 4 screw brass top coils 6 screw coils

[schwabd1]

Just picked up a 4 screw brass top coil for a spare on my ‘14. If I drill 2 more holes in the brass top do I now have a 6 screw brass top coil? In other words, other than the 2 extra screws, is there a difference between the 2 coils?

[DanTreace]

Seems to be only change. The two extra holes in middle were removed 5/14/15 so only 4 screws were used.

[schwabd1]

Thanks Dan….. I didn’t expect to run across a coil (I really didn’t have anything I was looking for), so no idea if it was any good or not. The wood is exceptional and I only paid $5.00. I tested it this afternoon and it’s dead. Oh well, I have a really nice looking paperweight. How much of a job is it to replace a good winding from a beat up coil into a nice box?

[Wayne Sheldon]

It takes a little bit of finagling, some slight of hand, but it isn't difficult to use common later coil internal parts. It has been several years since I have done it, so I don't recall all the details. Later coil centers are shorter than the brass tops, and usually will not exchange or slide easily. As I recall, on a couple I did, I used the later top wood piece, and carved out a bit of the wood so the inner coil itself could sit higher (takes less than a quarter of an inch).

Somewhere in all the many boxes of model T junk I have bought over the years, I ended up with a couple of the brass tops alone. Using genuine original brass top coils as my guide, I altered good common later coils to accept the brass tops. Again, raising the inside coil itself, and using some longer bolts for the points was required. Once finished, I have a hard time telling the later altered ones from the real original ones.
I prefer to use as much of the real ones as is practical. If the wood is good, but the coil windings are bad? I would fit a later inner coil into the earlier wooden case.