Bolt knob Checkering Revisited

Many of us in the Professional Gunmaking trade do not use checkering files as depicted in the previous post on this subject. In early 1980's Leonard Brownell with advice/help from John Rohner and Don Glaser wrote an article in the "RIFLE" magazine where by he described the layout and cutting of metal checkering on bolt knobs using the power checkering head (cable or pneumatic driven) that is commonly used for wood checkering. Many of us today use this method and rarely use the metal checkering files and sq/tri corner files for doing this work except maybe to assist in laying out the pattern. The carbide "saw blades"(either 90deg or 70 deg cutters) do the work of cutting the diamonds and spacing the lines. The powered graver making the borders and finishing the line to depth and to the borders. In Brownells catalog you can find bolt knobs already checkered and with double borders done by one of Stan McFarland's sons who paid his way through engineering school checkering bolt knobs. Jerome Glimm(Eng) from Conrad Mt used to do a large business of checkering and embellishing bolt knobs. Perhaps when I have more time I will put pics on the forum of the tools, layout methods and process of this method of bolt knob checkering that I have learned from those who came before me. Roger

rmgreen said:

Many of us today use this method and rarely use the metal checkering files

Click to expand...

The trouble is... both companies that produced and sold them are both gone and out of business. MMC and J & R Engineering were the two that were made to be powered by a Foredom flex shaft. I was lucky to get one of the J & R Engineering tools before Jon Doiron died. Jon's were made by NSK in Japan. I see that someone else is now selling the NSK power checkering head again: Hosford & Co.

Note: I just got off the phone talking with Jon Hosford, the owner of Hosford & Co. I asked him if the cutters he makes are interchangeable with the MMC and J&R cutters. He said his cutters don't thread on the shaft but have a hole of the size that allows it to go on over the threaded shaft. A nut with a centering collar holds it on. He says it's much more accurate. Also, his cutters are 15 tooth rather than 30 tooth and are titanium nitride coated. They are supposed to work well in steel. :biggrin:

Doc that is right and I have several of these heads including the Jon Hostford head also using either cable or pneumatic (NSK) power. He also is making the carbide cutters. Ullman Precision Products, ullmanprecisionproducts.com, making carbide checkering tools as well. Michael bought out what was left of the J&R Engineering tools/equipment/inventory. The Hosford power head is a super piece of workmanship with right and left hand version and the most precise spacing of any I have ever used over my 40 year career.

Thanks Roger, would like to see the photos and layout info

Doc yea i talked to Hosford yesterday. Tools i really need more tools