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Upsetting, Working small stock


Kendrick

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I've been poking about at blacksmithing for a bit now but I'm still working on the basics. I have seen some excellent tutorials on here but I'm having trouble putting some of the tips to use.

Right now I'm working on learning to upset stock. The problem I am running into is getting it to upset where I want it to without warping elsewhere. The two contributing factors I'm fighting is (1) I'm using a gas forge and have trouble limiting the heated area of the stock and (2) most of what I do is with 1/4" or 5/16" (some 1/2") stock. Any tips on how to work around these would be greatly appreciated.

Thanks,
Kendrick

Edited by mod07
clearification of title
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Kendrick, Like Finnr said chill where you don't want upset, use a small hammer, many light to medium blows, and keep true, don't keep upsetting if the piece if it bends, straighten it out and continue with upsetting.

I must admit that I find upsetting more difficult forge welding. Hope this helps,
Cliff

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Kendrick,
Both Finnr and CBrann have given you some very good advice.
I would like to emphise using "Quick medium to light blows" as opposed to heavy blows like what would seem more logical!
That is just my experence.
I know a guy who uses two hammers. One in each hand and looks like a machine gun when upsetting.
Have fun! ;)
Ted Throckmorton

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I had tried cooling with a ladle but that wasn't going well. The squirt bottle sounds brilliant.


A water bottle with a 'sports' pull-up top is good too. I understand that bladesmiths in Nepal traditionally use a teapot to precisely apply water (for a differential quench) when heat-treating khukuris, can't think of a reason why it wouldn't work here. A smallish dipper on the end of a handle is a good accompaniment to the slack tub, especially if it's got a pouring lip.

With upsetting (aptly named, for 'tis) the heavier the stock the more it tends to resist bending when at a lower heat. Think about taking two mild steel rods, the first an inch diameter, the other a quarter inch diameter. Imagine both have a fairly well isolated heat at one end. If you were to stand the quarter-inch rod on the anvil and upset the end, even when cold the stock will bend pretty easily. Now imagine doing the same with the one-inch rod.

Also, generally the heavier the blow the deeper it will penetrate; if we take that same example of a quarter-inch mild steel rod and bang on the end with the isolated heat using a 6-pound sledge it's going to go wrong pretty quickly. Do the same with a half-pound hammer and the end will upset or peen (as you direct the blows) more than it will bend and flop about.

There is a blueprint, I believe called 'upset helper' or somesuch, which is essentially a mild steel block with a number of through-drilled holes. The idea is to choose a hole slightly larger than the rod so as to give it some lateral support and reduce 'wobble'. Edited by matt87
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And now you know why it's called "upsetting."

One thing that makes upsetting difficult is directing the blow straight down the longitudinal axis of the stock, any deviation will bend it.

What I do to help control bending is to upset into the step. I lay the stock on the horn with the end to be upset against the center of the step and my hand holding the stock on the point of the horn. Then I hit the cold end as aligned with the horn and stock as I can.

As soon as it STARTS to bend I stop and straighten the stock and apply more heat. I have a smallish 1quart or so watering can with a straight spout I use to isolate heat. If the piece is short enough I simply quench it in the 15 gl. grease barrel I use as a slack tub, leaving the area to be upset hot.

Upsetting by hand is the one process that takes more practice to master than just about any other I've learned.

Frosty

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Ted T, I read that upsetting should be done with a small hammer, ignored that advice for a long time, then tried it. Small hammer works better than a warclub.

Got to say I am Glad I am not the only on e with "upsetting" problems. Not wishing them on anybody, I actually thought I was a dummy who couldn't figure out such a simple process.

Kendrick, you also can take a tin can, rivet it to a 18" to 24" handle, and poke or drill a few holes in the side on the top third of the can to have a sprinkler for spot cooling. Didn't put the hole in the bottom because if you have dirt in your slack tub it may plug up the holes if they are very small.

If they are not small than you have to have a dipper to fill it, and 3 hands to hold the hot stock, dipper and sprinkler.

Good luck,
Cliff

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I generally upset stock by heating the small end section, cool the bit I want to stay un-upset then let it drop onto a steel plate on the floor. Same action as using a crow bar (Ausie talk) maybe you call them sinking bars .??? spearing them into the ground tends to offset them so they need lots of correcting as you go. Letting them drop from around knee height is generally adequate. Also rotating the stock 1/4 turn on each drop also helps to keep the alignment. Good luck.
Cheers, Chris.

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Usualy for ''upsetting'' I use a rosebud to heat. there are several reasons for it:
1 heat much faster
2 very local and acurate
3 If you heat no more then a bit less then twice the OD of the steel and rotate while hammering the ''upsetting '' will stay in the center
4 one can upset many more itemes in an hour .
IF one is having no rosebud only gas forge one can use the system I show in the following
pic's
Take a piace of ceramic isolating hard board drill a hole very little more then the steel OD
stick the steel into the hole and out no more then twice the OD of the steel and put in the gas forge.
If I have many pieces of steel I use more blocks ,then when I am upsetting one the other two are still in the fire
Hofi

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One tip not listed so far is to lightly chamfer the end before starting to up set.
the idea is to direct the force down the center and not along the side. In my experiece it seems to help a litte. (could also be wishful thinking or I'm just paying more attention)

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