Knowledge You Can Build On — Est. 1998
Monster scraper set
Dick Parman
I am having Jerry of JA tooling make me a set of 3/8 tips for my Kobra rig, with the hopes that I can insert
Monster's 3/8 hex stem scrapers into them. Does anyone know if Monster's 3/8 hex stem will fit in a 3/8 round hole, or does it require a 7/16 hole, which is what a 3/8 allen wrench measures? Any reply will be appreciated.
Re: Monster scraper set
Dave Paine
Hex stock is normally measured across the flats, so the outer inscribed circle will be larger. I measured a 3/8in allen key which is 1/64in less than 7/16in between the points so a 7/16in dia hole should fit.
Re: Monster scraper set
Dick Parman
Thank You for the reply. Monster's ad says that their 3/8 hex stems will fit all 3/8 boring bars or tips. However, when I measured a 3/8 allen wrench it is, as you said, 7/16. So Monster either machined the edges down so that maximum OD is 3/8, or I need to have Jerry make the holes bigger.
Re: Monster scraper set
Dick Parman
Does anyone have Monster's hex stems to measure?
Re: Monster scraper set
Bill Blasic
They measure .312 across the opposite flats, will fit 3/8 hole.
Re: Monster scraper set
Dick Parman
Thanks for your help.
Re: Monster scraper set
Jorge Castaneda
Dick,
I am late to this party.
I have a Kobra rig too, so I am interested to know how it goes when you try it.
Thank you!
Re: Monster scraper set
Dick Parman
Jerry at JA tooling is making a new tip which swivels, to replace the 0, 22.5, and 45 degree tip he now supplies with the Kobra rig. He sent me the prototype of this tip, with a 3/8 hole, which will accomodate the Monster scraper tips. I tried this setup Yesterday, on a complex shape, hollowing about 12 inches deep. The tip performed very good and allowed me to finish (shear scrape) the inside of the vessel to a degree which did not require sanding. I am still amazed by the functionality of the Kobra system, and this new tip combined with the Monster scraper set makes it even easier for bumblers like me to end up with a flawless finish on the inside of a deep vessel.
