I came across this post on another website connected to engineering. It may help to explain what happened to J & R checkering tools, or why it folded.

IMPORTANT UPDATE

Jon Doiron, owner of J&R Engineering, died Wednesday, June 5, 2013, from injuries he sustained while skiing in Vermont on April 21. J&R Engineering will no longer continue to operate. Any hand tools and cutters found in Jons shop and available for sale will be listed on this web site. Customers with outstanding orders will receive a communication in the mail shortly.

Not much comfort for those who need parts, servicing or spare cutters.

Harry

Biology is the only science where multiplication can be achieved by division.