On Apr 22, 7:50*pm, Karl Townsend
wrote:
I'm on a snipe hunt for a special compression spring. it needs to be
conical with the large end OD around 0.390" or a bit smaller (like
3/8) and a small end OD of 1/4" or a bit smaller. *When the spring is
compressed to 0.225" high it needs to push 8 - 10 lbs. force. Similar
straight compression springs have 6 coils of 0.028" music wire and
constant of 25 lb./in.

I've been trying on line catalogs with no joy, so far. Anybody suggest
a good source to try?

Karl

I made a compression spring at the beginning of the month. In fact I
made several before I got it right. There are some good web sites
with information. So if you can't find one already made, you can make
one yourself.

I used the lathe, but turned the spindle by hand as my lathe will
only go down to 4 threads per inch and I needed about 2 turns per
inch. So turned the spindle a half turn and then moved the carriage a
quarter inch and repeat. It came out surprisingly well. The reason I
had to make several was to get the mandrel the right size so the
finished spring was the necessary diameter. i ended up making the
mandrel out of oak from a pallet . .750 was too big and .625 vas too
small so the metal rods i had on hand would not work.


Dan