Stupid question I know... but - What size is my Spindle Collet ?

[Fivetide]

Think I've seen Jonathan previously recommend ER20 because it can take collets up to 1/2 inch.

Andy , would I need to buy another chuck etc to fit the 1/2 inch tool, the specs for the tool is below ? Is mine a 1/2 inch spindle in other words ?

"The drag knife fits into your CNC router’s 1/2 in. router or spindle collet, making it a universal fit for almost any CNC router available."

[WandrinAndy]

Andy , would I need to buy another chuck etc to fit the 1/2 inch tool, the specs for the tool is below ? Is mine a 1/2 inch spindle in other words ?

"The drag knife fits into your CNC router’s 1/2 in. router or spindle collet, making it a universal fit for almost any CNC router available."

Sorry FiveTide, afraid I'm not sure as I've never seen one of these spindle thingies... I just put that bit of info aside for when I get there.... Eventually... Lol

Conceptually, I think a larger chuck would be required but I would guess that the diameter of the spindle shaft would determine/limit the chuck size that can be used?

I'm sure somebody in the know will soon pop along to enlighten us both.

Edit: Have just picked up the following from Wiki which may help.... "The "ER" collet system, invented and patented by Rego-Fix in 1973, is the most widely used clamping system in the world.^[3] ER collets are now available from dozens of companies worldwide. The standard sizes are ER-8, ER-11, ER-16, ER-20, ER-25, ER-32, ER-40, ER-50. The "ER" comes from an existent "E" collet which Rego-Fix modified and appended "R" for "Rego-Fix". The number is the cavity opening diameter in millimeters, which is nearly the outside collet diameter"

http://en.wikipedia.org/wiki/Collet

[Jonathan]

If the shank on the tool is 1/2", then ER11 is insufficient since, as GTjim said, that size collet will only accept up to 7mm. The minimum size collet series that accepts 1/2" is ER-20 which goes up to 13mm, so unless you can make some sort of adapter which is 7mm on one end and has a 1/2" hole in the other...you're stuck. That may be possible since a drag knife isn't spinning fast, so the rigidity isn't so much of a problem. Possibly the tool itself could be modified on a lathe to give it a 7mm shank?

Looking at the tool in question..

It looks like it could be modified, so long as it's not made from a very hard grade of steel, which seems unlikely.