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Started by Fla._Deadheader, December 26, 2003, 06:30:30 AM

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Fla._Deadheader

  There was the starting of some very important info on a recent thread, that kind of got off topic of the original thread. ( What else is new)  :D :D

CKTate and Woodhaven and "D" Frederick and AD Fields were touching on welding on a shaft and the topic drifted to "Hardening and Tempering".

  Don'T know about Y'all, but, that has always fascinated me and I have several books, but, I Don'T learn well from books. ::)
  It would be VERY interesting to me, and maybe others, if these guys or anyone else, would put some input to this subject.

  I know just enough to get by, but, would appreciate some knowledge, back yard learnin, or Scientific, College learnin, to help me understand the basic principles. The "Shaft Welding" post shows that some of us need some better insight, if we are to continue building machinery that could get someone hurt, from lack of knowledge.

  How bout it, guys??? ??? ;) :)
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

etat

 As said on the other thread, you weld around a shaft like that, or even like a lot of welding shops will do it, and failure is a option.  There are ways to reduce this option.  A shaft, whether cold rolled steel, or 4140 hard steel, when you weld around it with concentrated heat will change the structure of the metal, making it brittle.  That's why most welds of this type are doomed to failure.  The difference is concentrated in one small area, and in this case the area that will absorb the most stress.   There are ways to reduce this concentration.  The first thing, is figuring out how to hold everything together perfectly square, not a small task, as you know.  Now, in the case of a shaft preheat the metal.  hot.  This will help spread out the heat when welding and save damage to the metal itself.  Don't just start on one side welding around, or it will warp and pull, just as some lumber will if you don't stack it properly and weight it down.  Tack it in place, check for square make sure the tacks are free of slag and air bubbles, and continue to join the welds in short beads, alternating from side to side.  Once welded, reheat the whole shaft and allow to cool slowly, preferably by packing in something that will hold heat.  This will anneal the shaft if properly done, back to, or close to, it's original strength.  Another way, is to take your time, and allow each opposing weld to cool down as you go.  This way won't be as strong as preheating and annealing, but will do for most purposes.
Old Age and Treachery will outperform Youth and Inexperence. The thing is, getting older is starting to be painful.

Fla._Deadheader

CK  :o Ya put too much in this one post  :o :D :D
  Where I am headed with this thread, is, getting book learning AND field learning, mixed together, to get some REAL good info.
  My experience is starting with a Forney Buzz-box, and welding Galvanized steel, first thing. Got pretty sick, real quick.

  Did exactly like you, play and pay attention. Finally got a GOOD welder to show me some tips.
  Moved to a farm and had to learn real quick. Had a neighbor that was a Certified Oil Pipeline Offshore Welder. He taught me some tricks and WHY you do things a certain way.

  I taught my son, and he has figured out some things besides. Why you Don'T do some things, is more important to me.

  You touched on the shaft welding and it being porous and filled with Carbon, and the weld is no good. THAT is what I picked up on the wheel hub weld on T's mill. I was thinking about how to approach him about it, and "D" and AD took the lead. That weld had me scared to death. T took the info in stride and I hope he gets some good info out of this thread, along with the rest of us.

  When I decide to build something, I usually ask the guys at the Steel Co. what they suggest. That is NOT always a good idea !!! For instance, I used a piece of cold-rolled 1" round, to make the clamp assembly for our mill. It reinforces the hydraulic cylinder. Well. it's bent and goes up and down slowly. I went to the Steel Co. and got Stainless plate and Aluminum plate and asked about a "harder" 1" round.  Well, we got hot-rolled-, cold-rolled, stress, and can't remember the other. It is so hard, if you bend it too far, it shatters. OK, what's the best for my application? Guy says, whatever you want  ::) ::) >:(  I bought a piece of "stress"? and probably will upgrade the clamp to 1½" the next time we get it to the shop.

  Need to keep these posts relatively short, so the info sinks in.  OK guys, jump in here with some technical stuff, and splain it so's we can understand it.  ;D ;D
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

etat

S-o-r-r-y  ;D ;D ;D  PS milk will help counteract the sickness associated with galvanized fumes!  A fan blowing them fumes away from you is better. Better yet, grind off the galvanize before welding, or remove with muratic acid.
Old Age and Treachery will outperform Youth and Inexperence. The thing is, getting older is starting to be painful.

Fla._Deadheader

Yeah, sure, Where were ya in 1971??? ??? :D :D :D :D :D :D
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

etat

Old Age and Treachery will outperform Youth and Inexperence. The thing is, getting older is starting to be painful.

D._Frederick

First I will say  that I am not a certified welder, but with a lot of years behind me I know what will work and what will cause problems. Sktate did not hit on the correct welding rods or wire. I am close enough to  welding supply places that have staff that are knowledgeable enough if I tell them what type of iron/steel that I want to weld that they will give me the correct rods. If you are using used metal, take a grinder and grind on it and note what the sparks look like. The welding supplies have pictures showning the different sparks patterns indicating type of steel. Buying steel is another whole field, a good steel outlet will have engineering spec's , some of them will have people that can steer you in the right direction.

The biggest problem most do-it -your-self welders will have is with warp (like with welding track together). If you go to a shop/factory that are building something that must be straight, you will see that they have fixtures to hold the pieces during welding to prevent warp.They also use a welding sequences, not just random welding.

If you have been reading my posting, when some one asks about building something, I am mostly negative because 80% of the people don't have the skill level.

Fla._Deadheader

Thanks "D". Presenting your input is what this forum is about. Being negative is fine, as long as you point out what the problems you see will end up doing to the project.
  One thing I TRY to remember, is, how did I get started and the fact that I knew nothing, in the beginning. That is why I am asking for anyone's input here. ;)

  One other thing, the way that businesses are bought and sold today, you can't always depend on the owner OR the sales people to KNOW what they are talking about. A LOT of places don't even know what they have to sell :o ::)
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

jeepman

What are you looking for insight into, tempering or welding of shafts? I am a certified welder and weld shafts often, I may help with that. My tempering and hardening skills are hit and miss at best. I can't help as much as I can confuse on that subject.

D._Frederick

Jeepman,

Please go through the steps that would produce a weld that would be reliable on the hub shown, Note the steps need, maybe somebody else can fill the holes on heat treating/tempering. Your help will give insight on the skill needed so people will not "get in over there head" and weld something together that will come apart with bad results.

Fla._Deadheader

  Hi Jeepman, What "D" just posted is kinda what I am looking for.

  As I wrote earlier, when we design something, I try to figure what will happen if I do something a certain way. I think, knowing what WILL get someone in trouble, is more important than, let's build it and see what happens.

  I hope the guys using tires and wheels building a mill, are aware of how much energy is unleashed, if the weld or shaft or bearings let go.

   What heat does to steel, as in, crystalizing or warping or whatever, might be good info. Heat treating would be good. I know that is a field of it's own, but, as CK posted, "I have done it this way and it worked pretty well", to me is pretty good info. Stuff like that.

  If the info gets really good, it could be condensed and put in the knowledge base on the forum, for anyone to use as a reference.

  Glad you decided to jump in here. ;D ;D
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

etat

I'll be the first to admit that there may be better ways.  I too would like to hear them.  I disagree with the spark testing to determine steel type.  Much better to know what you have to begin with.  While it is true that a very experienced person can tell from the spark, even down to the exact type of steel, there are a lot of variables to look for, and this test can very well be misleading to the novice, and as I understand it confusing even to some experts. Too many types of alloys out there now. I wouldn't dare attempt it myself and then say absolutely what type steel I thought the results were.   I stand by what I say on the preheating and annealing on shafts until I absolutely know that there is a better way.  There may be better rods for the purpose, this is what I have had the best luck with, and havn't had anything to fail in quite a while. I do pay an extreme amount of attention to detail.  It is my opinion that folks are going to continue to build things.  Many will try reguardless of what is said.  As Fla. said, maybe more information will help at least a few from making mistakes. As for tempering and hardening cold rolled steel, it ain't going to happen.  No matter what method you use.There are  two ways to relieve stress in it.  One is peening it when hot, the other is annealing. Or taking your time, not getting it too hot, and not allowing too much stress to build up in the first place. :) If there were a occasion that you needed a hard surface on it, you would need to do it with a hard surfacing rod, and machine it back down.  But that will not harden the whole thing.  Sorry Fla. If I'm out of line. If yall think I am let me know and I'll delete this post. ;D  Just tryin to help.
Old Age and Treachery will outperform Youth and Inexperence. The thing is, getting older is starting to be painful.

Duane_Moore

 8) Dumb farm answer, wipe the galvanized with vinegar first? can weld, paint or what ever,  Duh, Duane.  also when cutting stainless steel use onion as a lube on the saw blade, well what ya want,  me from wyoming,  Duh ;D ;D
village Idiot---   the cat fixers----  I am not a complete Idiot. some parts missing.

ADfields

Spark test will tell you the carbon in steel if you know what to look for and MUST be done on a grinding "stone" not a carbon wheel.

Heat treating is more involved then this forum has room for! :P :P :P

When talking steels the faster you cool them the harder they get.   What cktate laid out as "tempering" is in fact called "annealing" not tempering.   When you temper steel you heat it red and cool it as fast as you can, this step is called harding.   Next step is to apply heat and remove some of the hardens and this step is the tempering.   There are endless ways to temper but the best way for a guy at home is to draw colors in the steel.   This is done by polishing the hardened steel to bright shinny steel so you will be able to see the colors as you draw them.   Next apply heat to the thickest part and watch the colors run, first is a straw then purples then blues.   The darker the color the softer the steel and when you have the pattern you want and quench it in cool clean oil to have a "tempered" steel.  

To me the right way to weld a shaft like the one we are talking of (with a compound load on it) is on the very end only, or like I stated don't go all the way around and give a crack a line to fallow around.   To repair a broken shaft I Lean to a TIG welder and someone who knows how to use it. ;)

Took me years of blacksmithing to find out what little I do know about this stuff. ::)   It gets very complex very fast but one of the best rules to remember is never give a crack a solid line to fallow all the way around or across a part or it will.  

I am always happy to help, it's the only reason I even post hear in fact!   I know I come off like a know it all sometimes and I'm sorry for that :'(  But I cant see someone headed down the road to the washed out bridge I just came from and not speak up. :-/   Thanks for putting up with me! ;)
Andy

Bigdogpc

First off, I ain't no welder.  CK is correct about working with unknown steel, steel is developed with specific properties for very specific applications.  Using found, unknown steels is the cheapest way to go but the risks are high.

"Tool steels must posses certain properties to a higher than ordinary degree, in order to make them adaptable for uses which require the ability of sustaining heavy loads and performing dependably even under adverse conditions."Machinery's Handbook"

The presence of carbon, usually in excess of .60% for non-alloyed types is essential for assuring the hardenability of steels to the levels needed for tools...hence the belief that high carbon knife blades are better

Tool steels may not be the best option for a given project, it really depends on the project.  O1 drill rod is readily available but not cheap.  The "O" designates it as oil hardening and is classed a cold work tool steel.  This is also available as an "A" designation which is air hardening.

Properties and applications:

AISI O1:A low alloy tool steel which is hardened in oil and exhibits only a low tendency to shrinking or warping.  It is used for cutting tools, the operation of which does not generate high heat, such as taps and threading dies, reamers, broaches and for press tools like blanking, trimming, and forming dies.

AISI O2: Manganese is the dominant alloy element in this type of oil hardening tool steel which has good non-deforming properties, can be machined easily and performs satisfactory in low volumn production.  Low hardening temperatures results in good safety in hardening, both with regard to stability and freedom from cracking.

STANDARD STEELS:

A numerical index for steel is used for SAE steel specifications.  The first figure indicates the class to which the steel belongs.  A "1---" indicates a carbon steel; A "2---" indicates a nickel steel, etc.  In the case of alloys, the second figure generally indicates the approximate percentage of the predominant alloying element.  Usually the last two or three figures indicate the average carbon content in "points" or hundredths of 1%.  Thus "2340" indicates a nickel steel of approximately 3% nickel and .40% carbon.

HARDENING TEMPERATURES FOR CARBON TOOL STEELS:

The best hardening temperatures for any given tool steel is dependent upon the type of tool and the intended class of service.  Whenever possible the specific recommendations of the tool steel manufacturer should be followed.  General recommendations for hardening temperatures of carbon tool steels based on carbon content are as follows:

.65-.80% carbon = 1450-1550 degrees F
.80-.95% carbon = 1410-1460 degrees F
.95-1.10% carbon = 1390-1430 degrees F
1.10% and over = 1380-1420 degrees F

Temperatures as indicated by color for plain carbon steel:

very pale yellow =430 degrees F
light yellow =440 degrees F
pale straw yellow = 450 degrees F
straw yellow = 460 degrees F
deep straw yellow = 470 degrees F
dark yellow = 480 degrees F
yellow-brown = 490 degrees F
brown-yellow = 500 degrees F
spotted red-brown = 510 degrees F
brown-purple = 520 degrees F
light purple = 530 degrees F
full purple = 540 degrees F
dark purple = 550 degrees F
full blue = 560 degrees F
dark blue = 570 degrees F
light blue = 640 degrees F

The above information is from the Machinery's Handbook, 20th edition.  It offers a wealth of information pertaining to tools, steels, charts, math, etc suitable for a machine shop.  They can be found (older versions) fairly reasonable and are very handy to have around.

I hope this will be of some use to ya'll

Fla._Deadheader

 Ahhhhhhhh, NOW we're gettin somewhere.  Don'T know why someone would think they are not knowledgable or hoggin the forum???  AD, if anybody thinks you talk too much, they will let ya know ;D

  A lot of stuff I do, is done without much thought, because I have done certain things so many times, it's habit, or, because I KNOW it will work. I think Y'all are doing the same. That's why I asked for the input in this thread.
  
  
  The tech info from Bigdog is great. I have so many books, that, by the time I find the right book, I forgot what I was tryin to build ::)

  When I was taught by the Certified Welder, he said to do the basic welding with a 6013 rod. That is mild steel and will get good penetration. THEN, if ya need strength, large bead in a gusset or a high stress area, weld over the first bead with the low Hydrogen 7018. That is high Tensile strength rod. I try to do this whenever possible and never had a failure.

  When I would clean up new ground, in Arkansas, I would follow up with a bottom plow. Points would last about 2 hours, because of the hard ground. I started experimenting with Truck leaf-springs, and would weld them on as points, right over the old ones. Once I figgered the correct angle of attack, them suckers would last 2 days ::) ;D ;D   Tried hard surface, but, not much luck.

  The Mig wire-feed is another whole dimension. We use that on 1/8th thickness or less. Can't get the deep penetration, so we may tack the project and then use the motor-genset welder and use the sticks. Get near 200 amps with that.

   Don't quite agree with Vinegar on Galv. and then weld. The Galv. is mostly Zinc and is usually a thick coat. Vinegar will CLEAN it, and take the oil off of new galv. so paint will stick. Best thing on Galv. is grind or use something else.
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

etat

I'm a thinking that if you need to build up a weld it will be stronger if you do it in steps rather than all at one time.  (A thinner bead around the middle, clean the slag and grind the edges, and follow with another bead on each side to build up will be stronger?.  I'm a thinking?  .............Machinerys handbook definition of Annealing:  A process involving heating and cooling applied usually to induce softening.  The term is also used to cover treatments intended to remove stress:  Alter mechanical of physical properties:  Produce a definite micro structure;  Remove gasses. Certain specific heat treatments of iron-based alloys covered by the term annealing or black annealing, blue annealing, box annealing, bright annealing, full annealing, graphitizing, malleablizing, process annealing:      And then it gets more, and more, and more, and more, complicated.  My machinery's handbook edition is 1946, and is One thousand nine hundred and eleven pages.  It is 13th edition.  Under heat treatment of steel............, annealing, annealing hide'speed steel, annealing temperatures, baths for heating, baths for quenching, baths for tempering, carburizing, carburizing steel, carburizing temperatures, cast hardening, cast hardening liquid and gas, cast hardening steels, cleaning work after cast hardening, heat treatment of steel colors for tempering, cyanide hardening, decalescence. Definations, drills, drop-forging dies, flame hardening, furnaces, furnaces for high-speed steel, harding ability test, Jominy, harding temperature, hardness at different drawing temperatures, heat treatmenst for S.A.E. steels, high speed steel, induction hardening, interrupted quenching, lead bath temperatures, nitriding, nitriding high-speed steel, non-ferrous metals, normalizing, normalizing temperatures, oil-hardening steels, pack-hardening, precipitation hardening, punches and dies, quenching, recalescence. salt baths, scale formations, solution method, spaheroidizing, strength and hardness data, sub-zero treatments, tanks for quenching baths, tempering, tempering in lead baths, tempering in oil baths, tempering in salt baths, tempering in sand, temperatures in water quenching.    Now I know, none of this helps at all, but it wll let you know the complications involved if you want to get into exact details.  Guess I'm saying to try to keep it simple, and deal with what most folks will be using.
Old Age and Treachery will outperform Youth and Inexperence. The thing is, getting older is starting to be painful.

Fla._Deadheader

Quote Now I know, none of this helps at all, but it wll let you know the complications involved if you want to get into exact details.  Guess I'm saying to try to keep it simple, and deal with what most folks will be using.

  Exactly what I been tryin to get across to anyone that would like to add stuff here 8) 8)
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

etat

Duane, is one particular brand of onion better than another?  If so, what is the best way to recognize the difference between these brands ;D ;D
Old Age and Treachery will outperform Youth and Inexperence. The thing is, getting older is starting to be painful.

Fla._Deadheader

Look for the Trademark, CK.  V_I_D_A_L_I_A 8) :D :D :D :D
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

etat

jeepman, won't you please come back and rescue all us wannabes who think we may or actually may not know the best way to weld up a DanG shaft.  please :) :) please don't let us scare ya off, most of us is jest a bunch of rednecks, or yoopers, or alligator chasers or texicans or something like that anyway.  DanG it, I hope I ain't left somebody out! 8) 8) 8)
Old Age and Treachery will outperform Youth and Inexperence. The thing is, getting older is starting to be painful.

Don P

Am I right in understanding that heating to the critical point is also the point the metal becomes non-magnetic, this is the indicator for quenching to harden initially?

Then can I draw the temper in the oven...I'll wait till the ladies are gone?

Does this only work for 10xx type steel, like 1075 and above or are many steels done this way?

I think that high carbon steels are adversely affected by heat in their tempering range ~500 degrees and high speed tool steels can withstand grinding heat up to about 1000 degrees?

I had an onion the other day on a roadhouse burger that I think deserves a try on that stripping galvy problem.

EZ

When ever I'm welding something and want it to be straight, before I even start the project I put it in my head that it will take time, alot of time. As soon as I think I got it made I start to get in a hurry and the next thing you know, warp.
EZ

D._Frederick

Warp has always been my biggest problem when fabricating with hot roll steel. To over come the warp problem, I end up using a lot of bolts. I will weld an assembly together, then bolt it to what every I am making. If it don't work or if I screwed it up, it easy to unbolt and add it to the junk pile.

How do the rest of you guy's overcome the warp problem from welding? Is there something magic you do?

Fla._Deadheader

We have a 2' length of ¼" X 2" Angle that we clamp stuff in, to prevent warp.
All truth passes through three stages:
   First, it is ridiculed;
   Second, it is violently opposed; and
   Third, it is accepted as self-evident.

-- Arthur Schopenhauer (1788-1860)

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