3Dogs, the UHMWPE would probably work well, but I think he is specific in wanting metal. I have used the UHMWPE to line many conveyor rub rails etc and it is neat stuff.

Sweany, thank for the link, I may blow that up and hang to inspire when I am trying to make the mermaid, assuming the fellow answers my query as to budget and other materials used in his boat.
Thanks all.

schtuff

Jeff, you are welcome.
Bruce, 2-50# hammers = 100# (BOG)

Mike, ya got a point there.
Reckon that Mayer hits as hard as my Fairbanks??

sisters

SWEANEY-- I think that has to be the sister of a landlubber gal that I dated way back there. I recognized her by the full, long hair, and the long slim arms and fingers. 'course the gal I dated had long slim legs.

Amazing how a fellow can have total recall --huh.GRIN

chuck

Thers a picture of Dave Hammer assisting one of the main demonstrators ,Mark Aspery , at the confernce in Bufflo.
Doesn't he look excited ?hehee

When Mark Aspery started his demo he asked "what's the three things welding flux does for you?"
Dave Hammer said " it puts holes in my shirts".
Mark said " okay , whats the four things welding flux does for you"? hehehheee

Problem

(and one comment from the gallery and I'll start posting my poetry!)

I've got a project I'm starting where I'm using stock much larger than I've ever used before. It's going to be a pair of andirons and since portions require about 1.5 square inches, I'm starting w a square 1.2 inch piece of stock (to avoid upsetting and keepeng everything in draw down.

OK, I haven't started, but spent some time fooling around w the stock (1.2 square about 20 " long). Normally for stock that long, I work w/o a glove and just hold it. The larger cross section really increased conductivity and I ended up quenching the end frequently to keep from burning my hand.

Allright, I suppose I could just wear a glove, but I hate gloves and suspect it would eventually get hot enough to be painful right through my welding gloves. I could use a pair of tongs (probably special made for such large stock) but it weighs about 10 lbs. and tongs will be clumsy (useable, but clumsy).

Since the piece of stock will ultimately be cut shorter, I was thinking about cutting a "heat trap" (groove) around the stock where it will be cut off anyway.

Have I missed anything? And any advice?

Thanx.

Beautiful weather in the Peoples' Republic of Insolvency.

Rudy, I've never heard of a heat sink groove. Hoipe to l;arn what others have to say. A moldy oldy piece of advice is to use tongs to quench the "cool" end of the bar, as many times as it takes. Works every time. And you don't lose much heat on the "hot" end.

A pair of andirons is a challenging project. Uses most of what a blacksmith does. Good luck and takes some pictures.

Rudy, I would offer that the conductivity is the same, as conductivity is a fixed value, more likely is that the larger piece, having to reside longer to get a soaked heat, has more time to conduct. I have never seen a heat groove used. I have seen a "water wall" used. This is a furnace front used in a gas forge to close up the gap around the billet, cutting down on dragons breath blowing along the billet. The wall is hollow, and a tube that the billet fits thru is usedto get the billet into the fire. Water is flowing at a rate that will not allow boiling, and then into a cooling tower, or in your case perhaps city water onto the ground.
Lots of setup.
I would vote for the tongs. A nice set of tongs will also damp the vibrations a little as well.

Rudy, You could use cotton hot mill gloves rather than welding gloves (I like the heater beater brand- that's a real name not a joke) or you can use tongs to manipulate or to cool as suggested. If you are using tongs to manipulate this larger stock first make sure that they fit well and then use a tong ring to reduce the strain you'd otherwise have trying to keep a grip on that larger mass. Good Luck with the project, Steve G

At some point along its length, a piece of stock will reach equilibrium, where the amount of heat conducted from the hot end will be equal to the loss to radiation and convection along the way. Heavier stock has a lower cross-section to suface area ratio, and will lose less heat in relation to the amount it can conduct. The will put the equilibrium point further from the hot end.

I'm not really sure how important this effect is in smithing. Sometimes the end of a bar seems to stay cool forever; sometimes it gets hot after you've been working the bar long enough.

Regardless, I doubt a groove would work very well as a heat barrier. I'm pretty sure that the amount of heat conducted along a bar is directly proportional to both the cross sectional area and the heat gradient along bar.

Imagine 1-foot section of 1" square bar that's 1300 degrees at one end and 100 at the other. That's a temperature gradient of 100 degrees/inch or about 12 degrees over 1/8". If you cut a groove around the bar 1/8" wide 1/4" inch deep, you'd reduce the cross section from 1 square inch to 1/4 square inch. That would reduce the heat flow, causing the temperature gradient across the grooved area to increase. In other words, the bar on the hot side of the bar would keep getting hotter, but the part on the cool side wouldn't heat up as fast as before.

Once the gradient reached 48 degrees though, as much heat would flow through the 1/4 square inch section as would flow through the original 1" square bar at 12 degrees. The net result would be that the cool end of the bar would stay 36 degrees cooler than it would otherwise be. Doesn't really seem to be worth the effort or the risk of the bar breaking prematurely at the groove.

Thinking a little more, the first paragraph of my post isn't exactly right. Eventually the *whole* bar will reach equilibrium. When that happens, the thicker the bar, the hotter it will be at any given distance from the hot end.

I guess its partly just what you are used to.

I forge stuff in that size range all the time. And bigger. I use tongs from Grant, and routinely hold 1" to 1 1/2" stainless round and square with em. Didnt think they were unusual or custom. In fact, compared to a lot of industrial shops I have been in, they seem pretty tiny to me. Grants tongs are always light and easy to use compared to swap meet clunkers, though.

I also wear gloves when forging all the time. Doesnt bother me in the slightest. Gotta admit, though, I do well over half my forging with the power hammer, where gloves are not in the way in the slightest. I use thin leather drivers gloves- when they get too hot, they communicate it to me, and I cool the metal down. Quenching one end while forging is automatic, when working with big stuff.
I often will batch stuff, forging one end, setting it on the floor or in the big water tank for the plasma cutter, and work on other material or jobs while it cools. Luckily, I mostly work stainless, which actually doesnt mind water quenching at all- with some mild steels, I dont like to quench, and therefore harden, so I have to wait more between heats.

I think a lot of it is just what you are used to. After the first hundred pieces, you dont notice things as uncomfortable or odd that seem so on the first part.

I get grumpy when I have to forge 20 foot pieces of 1 1/2" stainless pipe, though. The damn things get heavy, even with stands supporting them on both sides of the hammer, and, when they get hot, they tend to sag. Which means more fussy time straightening em out again at the end. I have done several projects where I had to texture a couple hundred feet of pipe like that. The boys who work for me will forge it, but they always make me straighten it, which I do cold in the hossfeld.

more

O.K. now you know why . But basically why not just get to work and do not get so much of the bar hot and quench the cool end just like Your forefathers did. This is how it has been for centuries. This could be the reason that there are water tubs on the side of forges. Even the ancient the story about King Solomon and the King of Craft has the town folks upsetting the slack tub. Trust me it wasn't there for the smith to bath in. So sometimes the obvious is really the answer.FORGE AHEAD.

PS The math isn't working for me either. 1.5 with 1.2

Cross section

Bill,

The math was a quick approximation. The square bar is actually 1.25 (1.56 cross section area). Also, I'm trying to have the blacksmith attitude. If it ends up 1.4 instead of 1.5 - it was a design change.

I *was* wondering where you found the 1.2" square bar. . .

Rudy

Based on my experience, (admittedly only a few times) making that transition in the heavy bar will work to greatly slow the heat migration toward the holding end. Enough to make a significant difference in your ability to hold it comfortably. I certainly can't tak about any of the physics involved since I'm just a blacksmith, not a physicist, but it does work based on empirical evidence. I usually just weld a smaller piece of bar onto the end for a handle and that takes care of the issue, but I know you like to work without electricity in your shop, so the groove might get you what you want. Or, forge the handle end down to be a handle, like we do for stuff on the powerhammer. Time consuming without a power hammer, though.

Like Ries, I use Grant Sarver's Off-Center tongs for stock up to 1-1/2" and they work great. A tong ring really helps with the arm/hand fatigue, too. Still, I usually just weld a handle on so I can minimize the amount of big stock I'm having to wield.

Sandpile

Will the chapter on the mermaid siter be in your book? (BOG)

mirror frame update

Well, I just dropped off the mirror frame sections at the glass shop. This was the project I asked for some advice about textured finishes a while back. Turned out what they wanted was, in typical Olde Virginny fashion an aged-looking guilded frame. So, I told the designer I thought she'd better find somebody with that kind of faux finishing experience to do it. She did & now it's out of my hands until the mirror segments get installed. It'll look like all tarted up like a New Orleans whore when it's done, but it's a job. We install next week, maybe. I'll post pix of the finished project.

Tom C

mermaid and keel rub strip

Well the fellow e-mailed back and has a $100 budget. He now has a SS strip he got from his Dad. He won't get much of a Mermaid for the $100:(
I think that one is dead in the water.

Mirror Frame

I'd be interested to know anyone's Mirror or Picture frame design. I've tried picture frames in the past with limited satisfaction. Specifically, how to create a sutable offset to hold the glass or whatever, and clamp same in place.

Jeff; when I worked with the swordmaker back in the 1980's we get folks coming in and wanting a custom hand made sword, perhaps 2 months work for the swordmaker and then say they wanted to pay *less* than the piece of high alloy tool steel cost...

Thomas

Jeff R

Jeff - Are you talking about a "cutwater" for the front of an old wood boat. I've made a bunch of those for a couple people that restore boats. $100 budget??? good luck. $100 doesn't go to far on custom trim that's polished to a mirror finish. Most of the old ones I replace are brass that have been chromed, I make them out of 16 ga S/S. Then I polish to a mirror finish. That way they don't have to worry about the plating shop possibly damaging it or during shipping. Sorry to hear that he doesn't want to spend some $$$ on the final trim that makes the boat look complete. - JK

Bird mouth

I've been experimenting - unsuccessfully. If you have a piece of 2" by 2" square stock and you want to taper one end to a chisel w about 2" of taper, is there a way (true path guys, no multi ton power hammers) to get that taper without "bird mouth". I've tried several different ways and no one I know has been able to solve it.

Rudy,

Hot cut hardy? (I don't know the real answer, if there is one.)

Jeremy, he wants a rub strip for the keel, due to stone bottoms in our local lakes, and wants it to have a forged mermaid at the upper end. Told me he "as a performing artist did not want to insult another artist" He was at least up front when I asked.

Rudy ?

If you are making a chisel point with no taper on the stock you have to upset the two corners back into the rod. It is more of an upsetting process than a tapering process. The bird mouth comes from the metal being pushed over the end try PUSHING IT BACK . start with the bar flat on the anvil and strike the top corner in, flip it over and do the same with the other corner. You will have to maintain the size of sq as you go . GOOD LUCK.

My previous post was in jest, but thinking about it: Assuming the bar had to be cut to length anyway, why *wouldn't* a traditional smith (that mythical character) have made the cut at 45 degrees or so and saved most of the forging?

bird mouth

Rudy - I think your talking about ?fish lips? that's what I call it. This was explained at a power hammer class I took and if you start the taper a little bit back from the end of the bar it will lessen that result. After part of the taper is started then slowly work the very end and taper down to were you want it. Steve Parker could probably explain it better. Or by doing a little fullering around the bar just back from the end a bit, that will drive the metal in the center of the bar outwards on the very end, now you can do the drawing out for your taper. Sorry I can't explain it that good...... Were's Steve Parker? Or there are plenty of others that will be able to explain it. You "can" combat that "bird mouth" Rudy and it is easy once you understand it. - JK

Bird mouth (fish lips)

Reason I don't want to just cut is I frequently end up w beautiful pieces of large steel (several inches across, etc.) that are just perfect for some project that ISN't going to end up looking like it was made from rod. i.e. stocky. That's my problem at the moment, although this is not the first time I have tried this.

I have a 4 lb. "cube" of 1065 that should be perfect for a 3 lb. hammer head I want to make. The extra pound gives me "forgiveness". If I really ruin it I can save most of my labor w clever filing and sawing. But, I want a pein on the hammer and getting that end down with out the bird mouth was a terrible job.

I have also had the same "type" of problem when working w any fairly large stock, where the center of the piece is not deformed much by the hammer blow. How was it done in the past? Or rather, is it easy to do if you're using genuine wrought iron?

MIKE

Please note The question was NOT how to do it but how to forge it with out a "bird mouth" you are actually correct But then again cutting two pieces the true path way could be a project too. Rudy seems to be teaching himself by finding the hardest processes he can. good way to do it, if time is not part of the equation

hammer

Rudy Look for a "swedish pattern" hammer . Much nicer than the german club you are trying to figure out.
Just the same forge the metal back into the billet , you need a wide pien and that makes it a little easier.

Fish lips and such

Rudy,

That effect comes from the surface of the steel moving without the core moving a corresponding amount. It is mostly due to lack of sufficient force - if you smack the thing with a big power hammer you'll see the end bulge out, since the power hammer has so much more force it drives the blow into the heart of the metal.

Also, if the stock is not heated clear through, the skin will be hotter than the core and therefore move more easily, with the same results. Be sure to take a soaking heat on big stock.

As Bill said, use blows that drive the corners back into the parent stock and force the middle out. With a hand hammer there's not much else you can do to combat the fish lip syndrome.

meeting today in Paoli Indiana of the Southern Indiana Meteor Mashers. Recruited some new folks at the demo last week, they are saying they will show-up.
Next week I only work 1 day, as the remainder of the week is shut down for change overs. Looks like August will see a little increase in production:)

I posted this question over at Jock's place, but I'll ask it here as well;

I'm working on a piece of sculpture, intended for an exterior location. I am contemplating fabricating and forging it primarily of stainless (304). It will be exposed to rainfall, but is not near the ocean and would not be subject to road salt spray. Were I to add copper or bronze elements, fastened mechanically, what would happen? If I were to braze them together, what would happen? The stainless elements would be no thinner than 1/4", the Cupric elements 3/16. I presume that the stainless would be the loser in any galvanic contest, but in this application, how long might that take, what exactly would happen structurally, and what would it look like. In the past, I have done similar things by using non-metallic bushings and fasteners to attach dis-similar metals, but this will not be practical here.

Three folks showed up for the meeting as promised. A guy and two ladies. They brought their boat on a trailer so they could go to the nearby lake for a swim after. The boat lost a wheel on the way, due to lug nuts getting loose on the aluminum wheels. They recovered the wheel, found a close parts house and bought some nuts, and limped in. The slide on the pavement had ground the U bolts that secured the axle to the spring mostly off. One U bolt was ground smooth to the clamp plate. They wondered if there was a local place that could work on it on a Saturday, as they had stopped at a couple of places and told no Saturday repair work. It seems that he did not understand blacksmiths very well:) The trailer was on jacks, the wheel off, the U bolts measured and off he went to the local, rural auto parts house which had U bolts, and then the old ones were cut off, a new clamp plate fabbed and they were ready to go, all the while his finance and friend were at the forge.
I think the Southern Indiana Meteor Mashers have three new members:)

Galvanic Corrosion

Here is a link to a chart and explanation.
http://www.engineersedge.com/galvanic_capatability.htm

As you can see, depending on which copper alloy you choose, the difference between many bronzes and stainless is .10 volts- well within the .15volt range they say is acceptable.

I have done some bronze/stainless combos, not near salt water, and admittedly we have only seen approx 5 to 7 year timelines so far, but no noticeable corrosion has occurred yet.
I would stick with mechanical fasteners, rivets or bolts, rather than welding, as that makes it much easier to repair in the future.

Thanks ries

After posting across the hall, and receiving a very helpful reply from Rich, I also came across the following, which confirms what your link suggests:

http://www.eaa1000.av.org/technicl/corrosion/galvanic.htm

It lists Bronze 655 and passivated stainless 304 as #70 and #71 respectively, in ascending order of nobility; Perfect! Copper and non-passivated 316L are not a bad match, either

And..

I'm most interested in your real-world observation, ries.

I am off all but Thursday this week due to plant shut down.
I split and hauled wood this morning. Green oak. Even though the logs were 2 to 3' in diametr, split pretty easy with a maul. Cut split and stacked about a cord yesterday and today.
Put the sand back in the outside wood burner after rebuilding the casing. The ice storm this winter brought down a tree that hit the stove. Almost ready for service. I have to have the heat exchanger for the domestic hot water boiled out as it clogged from hardness i9n the water. Then redo the stack out at the wood burner.

Finally also got to spend a couple of hours in the shop, forged an axe.

hot daytime temps

We were in Amarillo yesterday and at the Leather wholesalers. There was a guy talking about someone down south that had had a day or two of 110 degree temp. with 35/40% humidity. Folks with weather like that you can fry eggs on the cement sidewalks.

We did that in 1955 at Dumas Tx. during DOGGIE DAYS celebration. Dumas is the home of the DING-DONG DADDY FROM DUMAS, you may have heard the little tune. 1955 was the dryest, hottest, and one of the coldest years we had.

I had made a deal with a local man to train his litter of English Pointers. Making gun dogs of them. The summer was so hot all the pups wanted to do was flop down in the shade or flower beds. From daylight till an hour after sun up, you could get their attention pretty good, after that forget it. Fall was dry and windy they had a hard time smelling anything. A few of them made keepers in spite of the weather and a 14 year old kid working them.Grin
anything.

chuck

Chuck, we have been blessed this week with only 30 to 40% humidity and day time highs of 80 to 85F. Been getting donw in the 60s at night. Wonderful summer weather for this region that is often 95F and 95% right now.
Been off this week on plant shut down. Gotten lots done in this nice weather and only have to drink 3 or 4 quarts of water:) normal is 6 to 8:)

weather

It's been 110 or better for several days with humidity sometimes as high as 40 to 45%. Wish it would rain and break the heat. Too hot to do any forging. Looks like a nice thunderstorm to southeast this morning.

What doesn't everybody work out in their shops wearing an aloha shirt, shorts and steel toed sandals?

Humidity up to 25% already! We get most of our yearly rain as random thunderstorms and my area is in a rain shadow. Well at least the clouds make it cooler and provide beautiful light displays on the mountains and desert---there was *1* far off peak that was illumenated yesterday evening, bright gold when all the rest that were visible were dark.

Thomas

weather

We have been having beautiful weather here. Mid 70s and sun. Humidity is low because it is NOT raining.

Chuck, I always figgered that 15 minutes a day for 6 months would result in a fair gundog. After that time period the trainer becomes the trainee.

Working on a pattern welded cake server for a wedding gift. Hope it turns out.

training

BRUCE--You got it! Most folks don't understand that if a dog/horse/kid does something right three times in a row in five minutes---IT IS TIME TO QUIT and go onto something else. Attention span is short for a dog and a lot shorter for a horse and non-exsitent(sp) in a teen-age kid.grin

We used to set it up where the dog/horse could find the right answer and we'd be ready to reward them.

I once had BUSTER a Staffordshire Terrier that made a pretty nice gun dog. He pointed, honored, and retrieved cripples without mushing them. Retrieved on land or water out of a boat or off the bank. Could not use him late season not enough hair. had a wool-coat made for him--did not work that well.
Loved that Pit Bull.

chuck

shop-wear

THOMAS--Come -on man!! Can you see me or FREDDIE wearing a floweryed shirt and shorts??---HUH??
chuck

Why yes I can just see you both in that get up---memo to self: cut back on pain meds as they are having BAD side effects!!!!!!!!!!!!!!!!!!!!!!

Thomas

Back at the forge

I finally got back to the forge today. :) First time since I tore the tendon in the elbow last october. Not much hammering, but a lot of heating, bending, & tweaking. I made "eyes" on the end of 34 1/4" rods for a local wood working shop. Now he wants possibly 100 more. Didnt seem to stir up the elbow too bad. A nice easy project to get back into the swing of things.

Sure was nice to play in the fire again.

Back at the forge

Great your back at it Brian. Working is great for the soul.
Thankfully I'm injury free. Good genes I guess.

Been hard at it. The work is picking back up and is almost at levels that I was enjoying (or not depending on perspective, if you get my drift) last fall.

I look back at last year and realized how hard I worked. To bad it was all for not. got to work 2X as hard to make money these days........ lots of greedy people out there.

JIM