What are some after chamber checks and proceedures you do?
- Thread starter DSM
- Start date
JerrySharrett
Senile Member
Thanks Dave. I have Bausch & Lomb jewelers loupes all the way up to the 8/18x that I use so see detail with. After your suggestion to use this to inspect the ramps I tried a 2x. (I do have the 2x, a 4/7 and the 8/18x). With my poor detail eyesight I still can't tell much with the 4x though. The borescope lets me tell from an "above" view of the ramp length.
With a "from ground level" view with a loupe I could probably see well enough to inspect a non-benchrest chambering for irregularities.
Looking from above I can see about 0.050" (not exact, no, I didn't calculate this) whereas from the ground level there is only about (0.243-0.237 / 2) surface to view. Plus I want to see what my ramp finished surfaces look like.
Much thanks for this suggestion though. I'm sure it will be useful to many who do their on chambering or want to inspect a barrel that does not have the action attached.
I notice the B&L site doesn't list my 4/7 or 8/18 now???
http://www.bausch.com/en/Our-Products/Low-Vision-Product/Professional-Magnifiers/Watchmakers-Loupes
Dave Tooley
Active member
Jerry,
Try a 4X or 5X on PPC length chambers. Details will jump out at you. Depending on chamber length and caliber I can see the ramp. I also keep a close watch on my reamer. Any sign of wear and it's off to be sharpened before the cutting edge breaks down to far. The reason I like these loupes better than a bore scope is depth perception. Depth perception takes shadows and you don't get that with a 90 degree borescope except on the edges. That's where the loupe and focusing on the freebore works well. I had a borescope I got from Bill Gephardt years ago that had the light out front. Best I've ever used. I sent it off to have a camera fitted to it and UPS destroyed it on the return trip. Sad day.
One thing will agree on is if the barrel is set up correctly it's difficult to screw up the chamber.
Try a 4X or 5X on PPC length chambers. Details will jump out at you. Depending on chamber length and caliber I can see the ramp. I also keep a close watch on my reamer. Any sign of wear and it's off to be sharpened before the cutting edge breaks down to far. The reason I like these loupes better than a bore scope is depth perception. Depth perception takes shadows and you don't get that with a 90 degree borescope except on the edges. That's where the loupe and focusing on the freebore works well. I had a borescope I got from Bill Gephardt years ago that had the light out front. Best I've ever used. I sent it off to have a camera fitted to it and UPS destroyed it on the return trip. Sad day.
One thing will agree on is if the barrel is set up correctly it's difficult to screw up the chamber.
JerrySharrett
Senile Member
Dave, I wonder if these things doctors use to look inside the ear would work. My problem with looking in from the end is that I can't get enough light to see detail. My vision problem is magnified many times in lower light conditions. (remember, I'm 80/20 corrected in my good eye!)
Dave Tooley
Active member
Jerry,
I hold them up to an overhead light. Here's an example of what you can see. I had a 308 reamer that lasted longer than most and I've been keeping an eye on the chambers. It's still cutting very well. Not a hint of it getting dull. Throats/ramp looked fine. Yesterday I was chambering 9 308's and spot checked a few. The reamer had started to push up an edge at the end of the freebore in the grooves. I almost missed it was so small but it was there throwing off a slightly larger shadow. Using a bore scope looking directly down I wouldn't have seen it. I did my throat polishing routine on it and it was gone.
I hold them up to an overhead light. Here's an example of what you can see. I had a 308 reamer that lasted longer than most and I've been keeping an eye on the chambers. It's still cutting very well. Not a hint of it getting dull. Throats/ramp looked fine. Yesterday I was chambering 9 308's and spot checked a few. The reamer had started to push up an edge at the end of the freebore in the grooves. I almost missed it was so small but it was there throwing off a slightly larger shadow. Using a bore scope looking directly down I wouldn't have seen it. I did my throat polishing routine on it and it was gone.
JerrySharrett
Senile Member
Dave, what is your throat polishing routine, if you don't mind telling? On the 6mm bores, for example, I use an oiled 1-3/4 x 1-3/4 patch coated with an aluminum oxide lapping paste and just straight stroke the freebore/leade area till most of the tool mark is gone. With this I never get a green patch on break-in.
I have wondered if it is best to keep the handle, that keeps the reamer from spinning while chambering, as short as possible. The reason being is if you have ever used a torque wrench to torque wheel lug nuts, and used a long extension between the head of the wrench and the socket, you will have noticed that you had to use your other hand to keep the head of the torque-wrench in-line with the lug nut while applying torque. Applying torque, by way of the torque wrenches handle, also created a side-force to the head of the wrench that had to be resisted by the other hand.
My concern is therefore that a long handle on the end of the chambering reamer may also cause a side force that may cause some enlarged chambers. Therefore, keeping the handle that keeps the reamer from spinning as short as possible may help reduce the possibility of a side force. Reducing the reamer handle's weight would also seem to be a good idea for the same reasons.
My concern is therefore that a long handle on the end of the chambering reamer may also cause a side force that may cause some enlarged chambers. Therefore, keeping the handle that keeps the reamer from spinning as short as possible may help reduce the possibility of a side force. Reducing the reamer handle's weight would also seem to be a good idea for the same reasons.
I don't find this the case, at least the last chamber I made with it. Everything was concentric from base to leade. I see what you are saying though. My take on it is the tail stock is pushing on the rear of the collar and the force behind it keeps this from happening. Also, the close fitting bushing will help keep this from happening too. I'm only taking .030"-040" per cut at first and then drop down to .015"-.020" per cut once the reamer is cutting the full chamber. Probably could take more, but I like taking my time and keeping everything clean and neat.
I'm not so sure it has to be absolutely perfect. The reamer is just being pushed in a perfectly pre bored hole for alignment and not a lot of force is being applied by the tailstock to cut.
I'm new at this stuff, so don't beat me up too bad here, lol. I'm just trying to learn as much as possible to get the best chamber job possible. Something must have been right to warrant no movement with the Interapid. Will the next one be the same, who knows, but sure hope so!
What is your setup/technique?
JerrySharrett
Senile Member
If there is an effect due to a side-force due to the reamer handle it would show up as a slight increase in the chamber diameter, not as an eccentricity. Measuring with a dial indicator would not detect this. Certainly taking small cuts and not driving the reamer hard into the work would help to minimize any such issues.
Wouldn't that side force need to be in the exact location every time the reamer is pushed? Otherwise, it would show on a test indicator? The pushing surface is so close to the center of the reamer axis, I doubt a 1/2K or so would be of concern? Yes No?
Thanks for the input, lots of good info here...
The result of the side-force, which develops from holding the handle that is attached to the end of the reamer, to keep it from spinning, would be similar to a reamer which is held by a tail stock that is slightly out of alignment with the spindle - an enlarged chamber. If the handle is always held in the same attitude say, horizontal, the side-force on the end of the reamer (up in this case) will always be in the same direction. Its not the "push" of the reamer that would cause this issue but what method you use to keep the reamer from turning. A pure torque "force", applied on the center-line of the reamer would avoid this issue but how to do this without adding side-forces, or weight to the back-end of the reamer, is the problem.
The hand-held floating/pusher-type reamer holders would seem to possibly be a step in the right direction because these can be made light-weight and, being hand-held, you can somewhat compensate for the weight of the reamer holder, and with a smaller handle (or even possibly with no handle if your hand has sufficient grip) may be sufficient to keep them from turning.
I have heard that good results can be obtained with hand-held floating/pusher-type reamer holders. I am not saying that good results can't be had with the other type of reamer holders (floating or non) but I wonder if it may be somewaht that it is very difficult to really compare between the different types because very accurate eccentricity measurements are fairly easily to make compared to making very accurate chamber diameter measurements? I could certainly be wrong on this conclusion though.
B.Larson
New member
Pusher
my question was:"how do you know tailstock/Jacobs chuck (pusher ) is perpendicular to reamer axis"......
since Jacobs chucks are another joint in our set-up...and are notorious for not being an accurate holding device.....
I guess a guy could check the pushing face with an indicator for squareness...... I think it would scare most.... the readings they get.....
my question was:"how do you know tailstock/Jacobs chuck (pusher ) is perpendicular to reamer axis"......
since Jacobs chucks are another joint in our set-up...and are notorious for not being an accurate holding device.....
I guess a guy could check the pushing face with an indicator for squareness...... I think it would scare most.... the readings they get.....
Some thoughts,
From someone who actually uses a pusher...........from someone who bought a lathe SPECIFICALLY because of the pusher, someone who doesn't trust ANY other way. From someone who can make a chamber interchange brass without even seeing the old barrel, 5yrs later....
#1- as to "how" perpendicular and or parallel the answer is simple, you make it perpendicular. If it's fixed in the tailstock you friggin' sweep it. Anyone running a machine who can't effect or find perpendicular needs to go back to the drill press.
#2- when the reamer flexes (They ALL do! They ALL wrap up like Tigger's tail) THE PUSHER COMPENSATES! When the reamer tips left, the pusher forces it right back to center because the push surface transfers to the "high side" almost an inch away......
#3- if you're inducing a side flexure from the hannle you're holding it wrong. Your fingers grab near center, your pinkie and last finger keep it from spinning and your thumb should be pressing down. Altho I did once finish a chamber by letting the handle rest on a bar. Because my hand was hurt. The chamber came out "smaller than the reamer" which shows just how powerful the compensating action really is. I can't stress enough, "The PUSHER SURFACE Aligns The Reamer! NOT the handle. The handle is there just to keep it from freewheeling."
#4- folks who believe "accuracy" is the result of having "a straight machine" scare me. These are often the same people who meticulously turn and dial and pre-tension their setups by "dialing in the bore Dead Nutz on both ends !!!" and think they've done something....... ain't NUTTIN straight, you gotta' MAKE stuff straight! You gotta' find three or more points on rotational center UNDER LOAD and use them....But mostly you gotta' find the runouts and use them to your advantage
From someone who actually uses a pusher...........from someone who bought a lathe SPECIFICALLY because of the pusher, someone who doesn't trust ANY other way. From someone who can make a chamber interchange brass without even seeing the old barrel, 5yrs later....
#1- as to "how" perpendicular and or parallel the answer is simple, you make it perpendicular. If it's fixed in the tailstock you friggin' sweep it. Anyone running a machine who can't effect or find perpendicular needs to go back to the drill press.
#2- when the reamer flexes (They ALL do! They ALL wrap up like Tigger's tail) THE PUSHER COMPENSATES! When the reamer tips left, the pusher forces it right back to center because the push surface transfers to the "high side" almost an inch away......
#3- if you're inducing a side flexure from the hannle you're holding it wrong. Your fingers grab near center, your pinkie and last finger keep it from spinning and your thumb should be pressing down. Altho I did once finish a chamber by letting the handle rest on a bar. Because my hand was hurt. The chamber came out "smaller than the reamer" which shows just how powerful the compensating action really is. I can't stress enough, "The PUSHER SURFACE Aligns The Reamer! NOT the handle. The handle is there just to keep it from freewheeling."
#4- folks who believe "accuracy" is the result of having "a straight machine" scare me. These are often the same people who meticulously turn and dial and pre-tension their setups by "dialing in the bore Dead Nutz on both ends !!!" and think they've done something....... ain't NUTTIN straight, you gotta' MAKE stuff straight! You gotta' find three or more points on rotational center UNDER LOAD and use them....But mostly you gotta' find the runouts and use them to your advantage
JerrySharrett
Senile Member
I do not use a Jacobs chuck to hold the pusher. I replaced the center point in a live center with a narrow rimmed pusher that surrounds the reamers long axis but clears the reamer body by 0,020:" This provides a pushing force that surrounds the reamer but does not bias its cutting axis.
If the "pusher" is flat and square to the axis of the reamer, and no side forces are applied during reaming by a handle, etc., the reamer should follow the bushing's alignment with the bore. However, this is not a perfect fit with the bore and I believe then it would be the equal and concentric cutting forces that the reamer should develop as it cuts that would perhaps be the main factor in keeping the reamer co-axial with the bore. If the end of the reamer were to wonder off-axis with the bore/spindle for some reason there is really nothing about the "pushers" face that would encourage the reamer to move back into axial alignment. The "pushers's face would have to be concave to do this but then we would be back with possibly having the same issues that an off-axis tail stock would produce.
B.Larson
New member
Dusty Stevens
Hollow Point Dispenser
The bushing on the end of the reamer. It does the following so make sure you have a complete set and find the correct size with a pin gage. Make sure it engages before your prebore stops. I cant imagine trying to make a reamer follow a tapered hole but to each their own