OT Square hole?

[old-9]

Check this out. WOW! (hope it works) joe
Untitled URL Link

 

[CJ in Michigan]

Just the ticket for seating carriage bolts to N fenders!

 

[FMPreacher]

Could you imagin hav'in ta sharpen that thing?
God Bless You & Your "N"

 

[TheOldHokie]

(quoted from post at 19:30:42 11/29/11) Check this out. WOW! (hope it works) joe
Untitled URL Link

A variation on rotary (a.k.a. wobble) broaching. In the video notice the predrilled hole that is being "squared". Here's me "drilling" a blind hexagon hole in a special flat head screw I needed. The special tool holder produces the "wobble" and is quite pricey - many times the cost of the $75 broaching bit. For through holes an old fashion push/pull broach or an iron worker punch is still the way to go.

TOH

 

[old-9]

I knew you would know about this.I recieved this video by email and thought it interesting. I know a large punch press would be the way to go on flat metal but a blind hole in tool steel presents a different problem. joe

 

[TheOldHokie]

(quoted from post at 09:51:02 11/30/11) I knew you would know about this.I recieved this video by email and thought it interesting. I know a large punch press would be the way to go on flat metal but a blind hole in tool steel presents a different problem. joe

JMOR sent that very same video to me 3-4 weeks ago - it makes my head spin ;-)

TOH

 

[Cliff(VA)]

I have a blacksmithing book where it talks about drilling a square hole. You use a triangular bit and a guide plate with a square hole. Then you let the work "wobble" to get a square hole. It is basically the same technique, although in the video the holder does the wobbling.

Cliff (VA)