Unless your working a 3 - 4 inch dia. ring , I doubt normal freezing will make a measurable difference with calipers . But what do I know ... I will shut up and stop lighting off the short fused folks .
Unless your working a 3 - 4 inch dia. ring , I doubt normal freezing will make a measurable difference with calipers . But what do I know ... I will shut up and stop lighting off the short fused folks .
Last edited by Sig shooter; 06-02-2008 at 02:12 PM.
I have just asked that people try this method, and it seems nobody will. So maybe it's time I say goodbye to the forum.
Jerry
Honor is a Way of Life
NRA Benefactor Life Member
Calm down, Jerry. we don't break taps in aluminum every day.
Hi Jerry,
Just because people who have posted here do not want to try your suggestion does not mean that the rest of the non-posters do not hear you or would not / have not tried it. I am sure there are plenty out here that have listened and marked it down in "the book of things to be remembered". Years ago when I worked in an automotive machine shop we use to weld a pass around the inside of valve seats that were in aluminum heads. The pass on the inside caused the seat to shrink allowing us to just lift it out once it was cooled. There was never any damage to the head. We would then freeze the new seat and drop it in the head. So here we have a case of heat making something smaller then cold doing somewhat of the same thing. That alone was an example of how tempature does things that don't seem right.
Hang in here brother.
R.
"The only way to deal with an unfree world is to become so absolutely free that your very existence is an act of rebellion."
- Albert Camus -
Junior and Robert,
I have dealt with machining most of my life, I own a machine shop out here in BFE. This is one simple method for extracting broken taps. There are many other methods, including special tools to get the piece of the tap out.
If some one states an opinion without the experience behind, it shows a great deal of ignorance to me and the inability to think in the real world. I am not insulting anyone, because many people only think in simple methods and with a lack of experience. I even have people show up to my shop asking me to get a tap out of other materials, things like 4041 steel or Titanium. I use the freezer method with them. I do not recommend the chemical extraction methods because of the chemicals reactiveness and the possible damage to the work piece.
Some of them, I get out an old CO2 fire extingusher and while cooling the metal down, we have a couple of cold ones to sip on while doing this process. Today is a cool drink sipping day here.
I am building Bat Houses this afternoon, no machining involved.
Thanks for putting up with me,
Jerry
Honor is a Way of Life
NRA Benefactor Life Member
Hey Jerry, my idea was just that - an idea, and I have not tried your solution. I useta be a physicist, and could probably gin up some numbers to support my speculations; but experiment ALWAYS trumps theory! Next time I break a tap in aluminum, I'll give it a shot and see. Stick around; we need your insights!
Floodgate
NOV SHMOZ KA POP?
I'm no machinist but I think Jerry is right. It's the metal that's shrinking, not the hole. But you know what? All we have to do is try it before we go and say it won't work. Hang in there Jerry is't no big deal. Say, you ain't seen my wife in one of them houses have you?
Experience is the source of all knowledge.
Geeze,
I guess that it was me that started all this mess with my doubting words. Please allow me to explain myself a little better.
Based on my experience heating aluminum carriers to remove steel bearings & things like that, I know that aluminum expands & contracts more than steel does when exposed to a temperature change. I also know that when steel gets heat treated, it grows & holes in it shrink. That’s why die taps are slightly oversized. They allow the tapped hole to start out oversized so that after heat treat, it will be what you want it to be. Based on that experience, I said that I didn’t see how the freezer method would work. I was not calling BS on Jerry’s statement as another then posted, but I was expressing my doubt & hoping for more information. More information has since been provided. The freezer trick still seems unlikely to work in my opinion, but not having tried it, I can’t say for sure & I realize that. I don’t feel like sacrificing a tap just to test out the suggestion, but the next time that I do break one, I’ll give the freezer method first shot at solving the problem to see what actually happens.
A lot of people doubted my method of welding a nut to the remains of a tap & that worked out well. That was an example of popular wisdom being incorrect, as was the old wives tale about lead boolits needing to be kept under 1,000fps. This board is full of examples of people bucking the trends of popular wisdom to discover where the difference between fact & fiction really lies.
Jerry, please don’t allow yourself to be driven off by a few nay-sayers. Regardless of whether your trick works or not, it is something new to try that deserves to be explored. I for one appreciate the diversity of options provided by people speaking their thoughts openly. I hope that you will remain here as a contributing member. I apologize if my post seemed like it put you down or inspired others who did. That was not my intention. If your trick actually does end up working when I try it, I will then thank you for it
From a related field of endeavor –
Engineering: the fine art of obtaining knowledge by observing the unexpected after engaging in lengthy & painstaking calculations to predict the apparently obvious…that was actually wrong.
Anybody that’s ever been involved in new product development will attest to that.
Engineering is the fine art of turning theory in to a usable reality. I used to teach advanced math, physics and but mostly engineering. I have owned my own machine shop since 1994, and have listened to many old timers and tried their ideas out, most of them do work and very well.
There is an urban legend about the mathematician, the physicist and the engineer trying to say that a Bee can't fly because of, math - the drag to lift ratio, physic says the energy that the Bee has to the weight ratio and the aero dynamic feature prevent the Bee from flying. The engineer observes the Bee, who has go into flight by this time from being bored, the engineer want to know how to make the bee go supersonic despite the math and the science. That one is simple buy the bee a place on the space shuttle.
Many of these things I have studied at university even to thru my post doctorate studies, I make engineering practical, so the average person can understand what to do with the situation.
Plus I make some really nice rings on my lathe out of Titanium and Carbide, I tig gold in a fusing process and a whole bunch of other things in my day to day work. Today I need to make some bat houses or bat boxes for the local bat population. Instead of using pesticides or other chemicals to control the mosquito population I use some basic ecological engineering. Get what is known as the Indiana Bat to roost near the mosquito breeding ground. So the boxes becomes their seasonal homes. Each bat eats about a million mosquitoes a season. Currently I have two 50 bat boxes built and will work on a much larger one for breeding bats in. I will install them way up on trees later this week.
In academia this statement is not the norm, but is very true and is common:
Engineering: the fine art of obtaining knowledge by observing the unexpected after engaging in lengthy & painstaking calculations to predict the apparently obvious…that was actually wrong
When I state something, it comes from experience, some times I even say 9 of 10 times it works when such a statement is applicable.
Right now, I am trying to calculate the a Lee 7mm, 130 gr bullet mold, mill of the gas check portion, look into making this a HP mold, trying to get the weight down for my 7TCU barrel and shooting of the 7 TCU cartridge. Other than the cost of the mold, it is my time and experience to do such a thing. I am figuring it will be 110 grains when I get done, give or take a few grains either way. From that I can derive much knowledge on how it is done and what would be the pluses and minuses of doing this, in short, more engineering and machining knowledge to pass on to people.
So when I say try it, it is worth trying. Plus I have digital calipers that are good to 4 digits to the right of the decimal point.These are my HF calipers, I still have a great number of the vernier type of caliper, gages and mics.
If we want to talk about getting the tap out of a block of aluminum cost effectively, recycle the alumnum with the tap still in it and start over again. We seems to waste a lot of time in trying to make something work, when it is easier to replace it. That is good time management, something I took during my masters program.
Jerry
Honor is a Way of Life
NRA Benefactor Life Member
Oh I forgot to mention the answer to everything is 42.
Jerry
Honor is a Way of Life
NRA Benefactor Life Member
I fooled around with that a little when I was looking into some processes up at a place called Michael Anthony Jewlers in Mount Vernon NY. Those guys produce a LOT of gold jewelry. They've got their processes just about down pat. The gold fusing with a Tig takes some fine tuning to get set up right, but when it's set up perfect, you can't even see the seem. The big brew ha ha when I was up there was finding a more precise way to control the thickness of the gold foil they extrude. .0002" wasn't good to keep them happy. With the price of gold these days, they're probably back on that kick again.
JIMinPHX,
To leave the earth, the shuttle has to be going about 17,500 miles an hour or Mach 25.
Besides the machine shop I own a jewelry studio. My website has some of the stuff that I do:
http://anvilsandinkstudios.com/studiopage3.html
http://anvilsandinkstudios.com/studiopage2.html
http://anvilsandinkstudios.com/studiopage4.html
http://anvilsandinkstudios.com/studiopage5.html
You can explore the rest of my webpage at your leisure.
I only do one of a kind pieces these days and make replacement parts for a few different machines. My partner runs the company now, so I can play with my toys.
Jerry
Honor is a Way of Life
NRA Benefactor Life Member
Looks like you have enough equipment there to be half way dangerous. Looks like you keep a nice clean shop too.
JIMinPHX,
Thank you, I am working on a .308 Win. barrel that is very heavy at this moment, I am going to flute it and fit is to a Seiko receiver. Last week I repaired the crown gear for a 68 GTO. Tomorrow I will be setting a nice 1/3 carot diamond in a belly ring for a nice looking 30 year old.
I keep busy, and if it will stop raining around here, dry out some I will go out and try my new RD TLC311-165-RF boolits. Then tune up my 7 TCU Super 14 contender. I think before then I have to tranfer some low sulfur coal to my new storage area, that can be some hard work, this is about 1,800 pounds of coal.
Have a great one and thanks for the compliment,
Jerry
Honor is a Way of Life
NRA Benefactor Life Member
I have removed a broken tap from Aluminum by using a powderd form of Aluminum Sulfate .It was years ago but still have the bottle up on a shelf above my lathe .The idea is that this stuff when mixed with water eats away at the hardest metals .It also puts a neat finish on the aluminum.I found this tip when i used to make model steam engines .I think it was a hint in a catalog from a place called Coles Power Models .Arnie
Freezing a steel tap in aluminum does seem to work. I can not explain it.
It however, it is not from the aluminum hole expanding. When material with a hole in it is heated the hole expands. When material with a hole in it is cooled it shrinks. In engineering terms, “Every linear dimension increases by the same percentage with a change in temperature, including holes” This link explains it very well http://hyperphysics.phy-astr.gsu.edu...mo/thexp2.html
Joel
Wow Jerry, nice digs there...Keep throwing out the ideas and solutions to our problems and quandaries. There is such a diverse bunch here, someone almost always seems to have a solution for ones issues. What a great resource to casters and shooters.
Take a kid to the range, you'll both be glad you did.
"When a solid expands (or contracts) it does so in all directions however for simplicity only length increase is considered in your book" the linear expansion/contraction calculations are simply done because whomever is teaching this lesson isn't calculating the expansion ratio's in three dimensions so the argument doesn't apply here. I agree with Jerry on this 100%. The hole is a hole and will actually expand rather than contract as the aluminum (or whatever solid is surrounding the hole) contracts. Also remember you don't cool anything. You remove heat. Essentially this is all theory. If the man says it'll work, try it I'm sure in will.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |