High Speed Quoins

are you sure you are getting enough tension on them when in use? if yes then clean with a solvent, then you could lay some sand paper on a hard flat surface and “rough up” the working sides somewhat…

I had similar issue with some used ones I picked up. What worked for me was spraying into the mechanism with WD-40 and then working it for about 30 minutes, wiping the gunk away each time. If you do this, turn it on end too and wipe away what come from there. I went threw 3—4 rags for two quoins. They work like champs now!

I don’t get what the problem is, but disassembly and cleaning is what I do with a problem Challenge quoin. There are just two straight pins holding the halves together. Drive them out with a correctly-sized pin punch. This way you can clean every surface thoroughly.
A Challenge quoin in good condition clicks with each point of expansion. If it doesn’t, the spring is broken, and sometimes the pieces can bind the mechanism. I don’t think the current manufacturer, Bar-Plate, sells replacement springs as Challenge did. The quoin will work without the spring but I wouldn’t rust it on a high-speed press.

parallel imp is correct here about how to fix a non-functioning Challenge hi-speed quoin. I have a bunch of those springs somewhere. Didn’t even know what they were until informed of such by parallel imp.

Nope, not for sale. Mainly because I don’t have any desire to go look for them and then have to bicker about pricing. Easier to just buy used quoins on eBay or new quoins from Bar-Plate. And be grateful they still supply them. Because they will discontinue the item (and forever) if there are no buyers. That is how it works.

Support the suppliers.

Gerald
http://BielerPress.blogspot.com