- Location
- The Kawartha Lakes Region in Ontario
No way you can beat the repeatability, reliability, and accuracy of the reamer with a boring bar. Solid carbide roughing reamer, and finishing reamer.
chambering without reamer!
- Thread starter peterdobson
- Start date
No way you can beat the repeatability, reliability, and accuracy of the reamer with a boring bar. Solid carbide roughing reamer, and finishing reamer.
Again, I want to see the boring bar which is going to produce the required finish and dimensional consistency especially when it is going in to take a too-light cut in an attempt to clean up a botched chamber. The virtual chamber might come out fine but the real one won't.
I am reminded of the guy who claimed his Cincinatti Milacron would cut to within .0002". The truth was, it could be programmed to within .0002" but, thanks to tool deflection and material variations, it actually machined to not much better than .002". The difference between virtual reality and the real thing. At some point, tool design is the determining factor.
Well, I guess I just need to do it, and I will. For now, all the parts I've made that are flying around above our heads with much tighter tolerances and surface finish requirements than a rifle chamber, with deeper length to diameter ratios will have suffice to say anything can be done. Or the the top tier gun smiths who a doing it now can. Take your pick.
That Cincinnati must have been a dinosaur. My machines all program to .00001", and that's without glass scales yet.
That's wonderful but what a machine prodrams to and what a tool will cut are two different things. Name for me one of these top tier gunsmiths who has chosen to eschew reaming and go with a boring bar. I don't want to hear about the guys who rough with a boring bar and finish with a reamer. Many of us do that. You are claiming the boring bar does it all because it is set up in a CNC machine. Hogwash.
Please see above.
See Guntech's comments. FWIW, I wholeheartedly agree with his read. And Leeper's.
Your machines may well PROGRAM to however many decimal places, but if they are actually cutting repeatedly to that many, you and your machines are wasted on low tech junk like airplane parts and hydraulic valves!
LOL! Yep! Powerful stuff too! Hows the punchline go? "It promotes growth, and is very powerful!"
Much like buying your own hammer forging rig, buying your own CNC for the purpose of chambering, seems like a pretty darn fast way to have your name on an Auction Flyer to me. Short of going full on into production, where the returns 'might' justify the investment if the company actually found the work, it just seems to be one of those interesting mis-uses of tools that are better off doing something that actually pays for themselves.
Leeper;
Top of the morning to you sir from the sunny south Okanagan, I trust all is well in your world.
It's been way, way too long since I've said hello to you, I believe the last time was when you explained to me how to get a '96 Swede barrel mounted into a '98 action. I did find a 'smith to do just that sir and the result shoots monometal bullets with satisfying consistency.
With the understanding that I'm not a gunsmith, nor a papered millwright, as part of me making a living I've been involved with cabinet making CNC routers for nearly 30 years.
Before someone points out the obvious differences in tolerances between say a CNC over head router and a CNC Mill or Lathe, please understand in that capacity I also chatted with local machine shops who owned and ran CNCs.
Where to begin...... well they do allow amazing precision on repetitious parts and pieces for sure.
Setting up for a new piece/part can be vexing indeed and just because Skippy the programmer can whip up a program in 5 minutes absolutely does not guarantee the machine will hold the part or Johnny the operator can make it all come together in under an hour.
With use all machines wear out. The sensors need replacing or give incorrect readings, the computer doesn't understand what the sensor is telling it today, the electrospindle bearings - ceramic mind you - are a bit tired, so they heat up and send an error code which shuts the computer down...
Tomorrow as it happens, I'll happily receive a Biesse tech to work on our machine where I'm currently employed. He drives out from Vancouver and we pay all costs from the moment he leaves until he gets back home... in the old days in the last cabinet shop I managed, the bare minimum service visit was $1500 and I was happy to pay it because otherwise my $150,000 - that 1990's dollars too - was quiet......
Typically for our larger machines, I carried something around $20,000 of spare parts on hand at all times because if I didn't, the 5 week turnaround for parts from Italy would shut down the business.
In summary then - in my experience here in semi-rural BC - CNC machines offer a wonderful level of precision and production for some parts and pieces. I remain unconvinced however that it's affordable for any company or business that's turning over much less than $2 Million annually. Again that would depend on profit margins and the furniture/cabinet business is notoriously low - but the business I managed was $5 Million annually and keeping the CNC's ticking along was a major item in my budget calculations.
Anyway, sorry for going on so long Leeper, it's just one short guy's experiences over 3 decades I thought I'd share and worth only what time it took to peruse.
All the best to you folks as we head into spring.
Dwayne
Just read you (broken)link. That is a couple guys saying they did it, but it wasn't practical or cost effective.
And I will not believe that you are actually cutting consistently to a hundredth of a thousandth of an inch, any day of the week. Nor would I ever believe that a company that could afford to buy the rarified equipment that CAN actually cut to those tolerances, would ever use it for as mundane a purpose as chambering a rifle barrel, when there is good paying work to be had that might actually pay enough to make the machine payments and payroll both.
FWIW (not much, I know) I have actually seen a bunch of six decimal place prints. Usually they were from some dude that had enough clues to get a CAD program running, but not enough extra ones to change out the default dimension tolerances in the program.
I have had a fair few of "those" conversations.
"This part can't be made the way it's drawn."
"But you are supposed to be the Expert!"
"Yep, and I am saying that the way you drew this, it can't be made."
"Of course it can, make it like the drawing!"
<sigh>"The way you drew it, it can't be made. The prototype was made up of a weldement, and you are wanting it made from solid"
"You are the expert, of course you can make it!"
Rinse, repeat.....Based on several true stories....
So, on the off chance that you can actually pull it off, I expect big things from you in Industry news. Otherwise, that shovel handle is starting to be at risk, but if you keep slinging poo, you might find the pony!
fingers284
CGN Ultra frequent flyer
- Location
- Alberta Cowboy Ranges
Man-o-man that was impressive...but that's not a chamber...and I'm betting craftsmen back In the 40's war years production could do the same object with a panto-graph machine & a Fordom cutter... think 7 million carbine stocks panto-graph duplicator cut in two factories in 3.5 yrs.
Yep. That's about how you sound from here!
I have a barrel on order from him. We will see how it turns out.
