Quote:
Originally Posted by foxfish
But that bit looks like it cuts a half circle not a full round? 
I cant get my head around imperial measurements either - I want to fire a 6.35 or 6.5mm spear.
3/16 = 4.7mm
9/32 = 7.14
5/16 = 7.9mm |
OK, first I don't think my experience building guns holds a candle to yours...and this is just based on what I have tried- ya know trial&error (bit more error than trial if you get my drift
) so take it for what its worth.
The half round will cut your groove for the spear to sit pretty in it, since the cutter is wider than your rip cut (1/4"- tight) it will create the "round"
Your spear is 7/32 (like riffe euro, right?) if so this may just do it for you. the shank on this bit is a snug 1/4" so rip a channel with your tablesaw a hair less than 1/4" (after you've made your trig slot) and at the depth you require for fins to protrode enough for them to engage wishbone-the riffe 7/32 fins may not function, as I have already tried it, unless you make your cuts extremely precise and intend to use only this size shaft- I like to leave about an 3/32 on the top part of the enclosed track (with the 7/32 shaft it will have to be shallower...which may weaken the top of the track), any thinner and it tends to crack, I also add some absorbing poxy to this area to reinforce it- once your rip cut is made run the half round thru it, the rip cut serves as your guide- this bit allows an enclosed track which will accomodate a 9/32(7.14mm which is what I would use) & 5/16 (7.94mm a better choice if shooting in rocks IMO) spear.
As an after thought you can probably use a 1/8" (first one on the list) but the shank is 1/4" but I know someone (forget who makes them 1/8") in a WCS perhaps you can grind/turn the shank down to 1/8" (maybe more work than what its worth)
[edit] found it
Solid Carbide Mini Burs never used it, but the price seems right...buena suerte dude!
