Wicked Edge custom rods/paddles

razoredgeknives · February 16, 2016, 2:04am

Josh: I don’t think “wobble” is the main problem with drilling long holes. In a hand drill, any wobble is taken up by movement in the hand drill. Variability in the material is what tends to drive the drill bit off course. I did a little video-watching on “gun drilling” which is the science of drilling deep holes. Gun drills are actually very different. For one, they are not twist drills. They are held stationary while the stock is turned in the chuck of a lathe. The drill has a hole drilled thru its center, thru which lubricant is pumped to drive out chips, which are pushed out along a full length V-groove. The tip is an offset carbide cutter. The real key though, is that immediately behind the tip is a section that fits tight in the bore. This guides the tip, holding it on course. Did you ever try that “tight tolerance” rod material from McMaster? My bushings haven’t been a problem at all since I went to it. My rods are 14″ long now and the bushings never slip off the rod end, although I don’t do any real long knives. I was interested enough to try the 3/8″ rod trick, but everything I needed added up to about $75, so I set it aside. If I had a problem I’d be more inclined to try it. BTW, I would have bought the 3/8″ ball joint coupling, then epoxied in a 1/4-28 set screw with a section of bushing to make up the rest of the fit. I don’t have access to a lathe to turn the 1/4-28 threads on a 3/8″ rod.

Which tight tolerance rod are you referring to? I may get some of the .375 to fit out my older gen rod arms I still have and use… I will have to measure these rods… I didn’t want to get too long if I can help it so the tips don’t bump into each other; do you find this is ever an issue? I’m guessing not!

That is amazing about the gun drilling!! Wow! I know on these holes I had a longer drill bit (probably 7" long) new, that I tried first had much more wobble than the Norseman shorter bit did. So I know I had some issues w/ that but it is probably more that I need longer bushings maybe than anything.

Josh, Your friend that made your custom rod used commercial available “drill rod”? Your custom rod’s threaded portion, appears to have used separate threaded stud…after drill rod’s end drilled/taped…short length stud threaded into end? Standard commercial precision oil quenched tool steel drill rod comes in 3′ length, so…in essence…your limit to rod length as well as paddle stroke to avoid bump hiccup is 3’…. However, there is work involved in making two end bushing to remain concentric…if your friend is a Machinist, then, should be a piece of cake, since Journeyman Machinist are rarely self taught…certainly is a bit more involve to pursue precision….. Your response to “tcmeyer” regarding variation in drill bit runout among bits….If I may….sometimes, problem lays within the drill chuck If hand drill drill motor is not of high quality or was misused at some point in time, jaws within chuck will not engage drill bit properly….in that event, it helps to rotate drill bit shank slightly to re-position, hand tight, recheck several times till satisfied, before using chuck key….

Yes I believe he used commercial available drill rod! And you have it exactly correct, the one end was drilled and tapped and a stud installed =) Very good eye!!! Are you a machinist too Victor?

razoredgeknives · May 5, 2016, 2:51pm

Well I ran into some issues making paddles w/ stock holes on them w/ tight tolerances… for some reason my drill bit is drifting in the hole a bit or something and causing a bend. That and the stock rods being able to be bent or not perfectly straight can cause issues w/ tight tolerances… But this threw me on another track… bore out the hole enough to where this doesn’t matter and then install linear bearings as bushings in each end. These are self adjusting so any curvature in the rods won’t make a difference. They are extremely tight tolerances w/ the stock rods with zero play and yet still smooth =) The key is to have rods long enough that the paddles won’t come off of the ends.

Would be sweet to mill pockets for magnets into the faces and then just switch out stones/lapping films/strops all backed w/ a magnetic steel. Still trying to figure this out…

victorf · May 5, 2016, 4:54pm

Josh, I supposed you did not consult with your Machinist friend on how to drill a concentric hole doing the Machinist way?

razoredgeknives · May 5, 2016, 5:27pm

I just asked him this morning… he said try peck drilling I think was the term… removing only 1/16 at a time. Do you have any more tips my friend?

victorf · May 6, 2016, 5:51pm

Peck drilling is new term for me..learn something new everyday! I get the picture!

Basic skills such as drilling appears to be simple…truth of the matter is - the more your think you know…the more you realized how little you really know!

tcmeyer · May 7, 2016, 7:08am

If I remember correctly, peck drilling is a process of drilling only a very short time before backing the drill out then repeating the process over and over.

Gun drilling, a process for drilling long, straight holes, uses a bit which is not a twist drill. The bit has a single groove, running in a straight line from tip to shank. The tip has a single carbide cutter and a small hole bored from one end to the other. Coolant is injected under pressure to drive the chips out of the hole and up the groove. Just above the cutting end is a short section of the drill which is full diameter. This holds the bit on its axis, reducing any tendency to drift off-center.