? chucking up a barrel ?

Jim, that is interesting, and the timing is perfect. I have been playing with grizzley rods as well. The dial responces have been
strange, implying other things at work here. I found the rods to be less than straight and when placed in a tailstock chuck , additional forces were added. The rod is flexing on many plains and may even be worsened by a close fitting pilot. At any rate
its not the best place for a dial reading. I did straighten the rod and numbers improved slightly. Thought about gripping the rod
with a short piece of neoprene tubing lightly and maybe grinding a small flat on the rod for the dial.
 
Bob,
I saw a picture of a setup where the indicator was one of the lever types, and the whisker made contact about half way down its length. Did you hang a weight from your rod?
Boyd
 
Boyd, yes I did hang a weight. matter of fact I tried different amounts and locations. At best, this is an indirect way of
measureing and as such is subject to problems beyond the issue. Not only does it move as it should vertically against the
indicator needle, but is also flexing horizontally. That changes the position of contact with the indicator, say from just
before 12:00 to just after. Different readings can also be had by changing how briskly you rotate the spindle. A less than straight rod,
or one that is in a stressed position is just not that reliable.
 
Boyd Allen said:
Jim,
Since we are stirring the pot...The rod that you used for your test, is not the one that Gordy uses. It is 13" long, and I believe that the instruction is to hold it with the tips of the tailstock chuck. Being an engineer (which I surely am not) I am sure that you are aware of the effect that doubling the length of a cantilever has. (For the rest of us, the deflection for a given end load is quadrupled.)

Also, related to Jerrys' question, what do you think about turning the shoulder and tenon after the chamber is cut, so that they may be perpendicular, and parallel to its CL ?
Click to expand...

Boyd
I am well aware of the effect of doubling the length of the rod-but that does not take away the fact that we are inducing strain in the rod. I "grabbed" the tip of the rod with the "end" of the jaws-but that still does not give you a rotary joint. Bob's comments also address that.

Jerry

Those eagles better be on their toes as we are just getting warmed up--just stalled by a snow storm of all things :)

On the crooked barrel-I indicated in both ends and then did not pre drill or pre bore as it was so crooked--I used the three piloted reamers to follow the bore-so the resulting chamber was in line with the bore -but not axial with the centerline of the barrel-so therefore the save head was not perpendicular to the barrel and lathe axis.

Jim
 
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I am still trying to wrap my mind around indicating throat and muzzle and then the pre bore and the eccentricity effects and angular effects-versus a reamer with snug bushing that is following a bore to yield a throat that is concentric over the length of the throat and the bore ahead of it. Have drawn it a number of times in CAD. the weak part of the setup still comes down to being concentric an dined up with the bore where the bullet engages. If we "dial in" and then pre bore concentric with lathe axis-then by definition the throat is misaligned by the accuracy of our "dial in". As many have already stated-there is more than one way to skin chambering a barrel and certainly more than one way has proven to be successful.

Can't wait for good spring weather for experimenting.
 
eddief said:
You make me think too much Jim....but I like that. What about capturing the end of the Grizzly rod in the tailstock chuck jaws via small piece of.... lets say copper wire around the rod, like so many do when chucking up the barrel in the headstock, to allow that pivot motion when dialing in from the outboard side of the headstock?
Click to expand...

Eddie
yep-that might work-or a rod that has a ball and socket that is extremely tight fitting like the old floppy indicator rods (not their real name-this aging mind just having hard time remembering their name tonight)
Jim
 
Jim Borden said:
Eddie
yep-that might work-or a rod that has a ball and socket that is extremely tight fitting like the old floppy indicator rods (not their real name-this aging mind just having hard time remembering their name tonight)
Jim
Click to expand...

If you use a ball and socket arrangement it'd be hoovis to wrap a rubber band around it, preload the joint.

I just chuck 'em short enough and light enough to swivel easily.....

al
 
Thank you Jim

Jim Borden said:
I am still trying to wrap my mind around indicating throat and muzzle and then the pre bore and the eccentricity effects and angular effects-versus a reamer with snug bushing that is following a bore to yield a throat that is concentric over the length of the throat and the bore ahead of it. Have drawn it a number of times in CAD. the weak part of the setup still comes down to being concentric an dined up with the bore where the bullet engages. If we "dial in" and then pre bore concentric with lathe axis-then by definition the throat is misaligned by the accuracy of our "dial in". As many have already stated-there is more than one way to skin chambering a barrel and certainly more than one way has proven to be successful.

Can't wait for good spring weather for experimenting.
Click to expand...



Here, you have perfectly described what I have been thinking all along and the reason I ream the chamber just short of depth as the first operation; before turning and threading the tenon.

Thanks for joining the conversation. :) I always look forward to your posts. :D

Gene Beggs
 
Jim Borden said:
On the crooked barrel-I indicated in both ends and then did not pre drill or pre bore as it was so crooked--I used the three piloted reamers to follow the bore-so the resulting chamber was in line with the bore -but not axial with the centerline of the barrel-so therefore the save head was not perpendicular to the barrel and lathe axis.

Jim
Click to expand...

Jim, does this mean the reamer base was oscillating in the Big Bird floater as the barrel curve rotated??
 
Jim Borden said:
Jerry

Eddie had it right (one thing I have to watch on this MAC is predictive spelling-and how it make save from case is beyond me)
Jim
Click to expand...
Yep, watch the MAC stuff especially SIRI. It thinks it knows what you think you might want to do if you had time to think about it. I think!!

My ME daughter now is an in-store instructor for the Apple stuff. I ask her if i-stuff was so great why did they need her?
 
Please tell me this. If one would chamber the barrel before cutting the threads, what part of the chamber do you re-indicate or check to see if the barrel needs a little re-adjusting? Would you have to indicate in two spots in the chamber or just in the neck? I really dont have a technique as of yet as i have only chambered one barrel. I need to settle my mind on one method and learn it inside and out. I read were one guy chamber's one way, and another fella does it that way. Both fellas very respectable men that i trust. I used a grizzly rod on my first chamber, and the barrel shoots just fine. Cutting the chamber first and then making any final adjustments before finishing the tenon does make since to me, but the truth is, what do i really know. Not a hole lot at this point!! Lee
 
skeetlee said:
Please tell me this. If one would chamber the barrel before cutting the threads, what part of the chamber do you re-indicate or check to see if the barrel needs a little re-adjusting? Would you have to indicate in two spots in the chamber or just in the neck? I really dont have a technique as of yet as i have only chambered one barrel. I need to settle my mind on one method and learn it inside and out. I read were one guy chamber's one way, and another fella does it that way. Both fellas very respectable men that i trust. I used a grizzly rod on my first chamber, and the barrel shoots just fine. Cutting the chamber first and then making any final adjustments before finishing the tenon does make since to me, but the truth is, what do i really know. Not a hole lot at this point!! Lee
Click to expand...

Skeetlee, I was of the understanding you used the tapered 'Range Rod' from PPG for your chambering. If so, these are not 'Grizzly Rods.'

If my memory's faulty, please 'scuse! ;) I get a lot of traffic and sometimes I mix people up.

BTW I chamber last because I time or index my barrels, point 'em where I want 'em.

fun

al
 
Al I used the grizzly rod. I am looking on ebay and waiting for a better deal on an intrepid indicator as well. This way i can reach up inot the chamber a bit further. This things usually dont sell real cheap. probably for good reason. I will find one before long, i am sure. Lee
 
skeetlee said:
Al I used the grizzly rod. I am looking on ebay and waiting for a better deal on an intrepid indicator as well. This way i can reach up inot the chamber a bit further. This things usually dont sell real cheap. probably for good reason. I will find one before long, i am sure. Lee
Click to expand...

Lee
Keep in my mind that you should keep the two methods separate. Do not try to use a Grizzly or range rod in throat area with a busing on it and also dial in the muzzle end. The range rod and grizzly rod in my experience only work when you do as Gordy describes-otherwise you will be getting false readings on rod due to the strain in the rod.

Jim
 
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