tips on forge welding

[MOblacksmith0530]

Beautiful piece Brian, I haven't had a chance to retry my test from the other day in the gas forge, but I will and next weekend when I am at the local Renaissance faire I will be trying some welds in the coal with the iron Mt instead of my borax. I really want to get the hang of the red heat tack because that would be so helpful.

[Jason @ MacTalis Ironworks]

Just ordered a bottle this morning to give it a shot, I've always just used plain borax unless dealing with high alloys... figured I'd give it a shot after you recommended it Brian. I'll let you know what I find.

[Matt Lumb]

All,

I thought i'd like to take up blacksmithing and have just started hitting bits of hot metal and trying to make things out of them. Had good success with bending/twisting/riveting etc but would love to be able to forge weld.

my aim is to make a chain without the mig. I have a three burner LPG gas forge, flux, and basic tongs/hammers.

i have been heating 12mm round MS bar up to a good (and thoroughly soaked) yellow heat and following the process below:

1) heat up bar to red hot and bend to make U shape for link
2)reheat to red and then scarf opposing faces
3) offset and bend/align ends so scarfs (scarves?) align
4) reheat to red and apply flux all round so i have a molten look to the area
5) heat now to yellow and fully soak ( i have richened the mixture by closing off to about 1/3 the inlet regulators to the burner and turning the gas up full. I have alight blue flame and the flames come out of each side of the unit mostly dark blue with orange streaks) i have darkened glasses and the link is yellow but no sparks and not too bright to look at with naked eye.
6)lightly tap with 2lb ball pein hammer ( i tried both flat and ball end)
7) it looked like it had taken and sounded like it was one piece with the cooling/colour uniform over the area.
8) i kept tapping until the link was red and then tried to gently shape the scarf, it then came apart.


I have tried this a few times to no avail

Can anyone help?

Thanks in advance

Matt

[iron woodrow]

stand 30 degrees from magnetic north and squint your eyes while standing on one leg. Then poke your tongue out the left side of your mouth...... :)

[jmccustomknives]

Try to do a simple faggot weld with two strait peices of stock ( :blink: boy, that sounded funny). It seems like you aren't reaching forging temp. Lean your forge down and don't hold back on the flux. I just use 20 mule team borax.

[Old N Rusty]

There is a hardy tool that makes linking chain a "snap" . I hope Glenn will dig out the film "shears" and link to it. In that film the smith has one of them in his anvil it is basically a block with a hardy tail and a hook on the side with a flat top and a deep fuller groove . to use it the chain is on the farside of the anvil with the last link across this tool in the fuller groove .When the new link is added the weld is supported by the hook for the first tap. You must practice lap welds , I am not sure a gasser is your best choice for a chain making forge. Good Luck!

[Drewed]

I weld at white heat, not yellow. Also do not rest the material on the avil even for 1/2 a sec before stating the weld. The hammer should "push" the material to the anvil. Also stand 30 degrees from magnetic north and squint your eyes while standing on one leg. Then poke your tongue out the left side of your mouth...

[ThomasPowers]

Forge welding is a process where it *REALLY* *REALLY* helps to have someone walk you through it a couple of times. If you post your general location you might get an offer from a local smith to work you through a couple of welds.

BTW Is the refractory in your forge flux resistant?

[HWHII]

It can be tough to make a forge weld in a propane forge. It just does not get quite hot enough but it can be done. I use a flux called Black Magic, this seems to help. You apply it like you would any other flux. When it comes up to temp the flux will be active and start to dance on the metal if you touch the two pieces together they will be sticky. Thats when you pull them out and lightly tap them together. Wire brush add more flux and put it back in the forge and finish the weld with firm blows. If I can I will tack the pieces together with a mig weld. I have made some welds at a bright orange. Yellow is better if you can get it. The weld still is not as good as a coal fire forge weld.

[Frank Turley]

I could write a pamphlet on "the dance" of getting to the anvil and horn for a link. The enclosed shows three old wrought iron links from New England, USA, and it dipicts the peaked appearance of a finished hand forged weld. This is for extra strength and can be done on the horn by careful hammering. After hammer welding both sides on the anvil face, the link is moved to the horn still at a welding heat and held at approximately 30 degrees, tong hand away from the anvil and toward the operator. Hammer with vertical blows while swinging the tong hand away from you. If you run out of heat, get it up to welding again and repeat on both sides of the link.

The pictured link is 12mm x 280 mm to start with. You can notice that the points of the scarfs are still visible. This is allowable only if the weld is solid in between those points, especially when inspecting the inside of the link.

[ThomasPowers]

"It can be tough to make a forge weld in a propane forge. It just does not get quite hot enough"

I and a friend have both melted steel in our propane forges, only 300+ degreesF hotter than forge welding at 2300 degF How is that "Not quite hot enough"?

Now some propane forges do not get hot enough but definitely not *all*!

You many note that most of the professional billet makers all use propane forges for welding up billets---including JPH.

If a propane forge does not get hot enough there are ways to tweak some of them to get there---increased fuel pressure, decrease volume of the forge, increase insulation of the forge, increase IR reflectivity of the forge, etc. However if you plan to do a lot of forge welding it is probably best to build a forge that is optimized for it!

[Rich Hale]

Reading your question the item that jumps out at me is that you tapped lightly with the light hammer and then kept on tapping. That first one or two taps starts the weld, then wire brush. flux and back into the fire,,a couple more light taps and repeat. later on as you learn how it all works it may not take four or five heats to get a good joint but for now try it and see. And it is much easier if you find someone that will show youi in person.......

[Francis Trez Cole]

there is a lot of videos out there this a good one hope it helps

http://www.youtube.com/watch?v=8jZDEtmDgxI

[Matt Lumb]

Thanks,

overwhelmed that i got so many responses;

I forgot to mention that I use a Diamondback three burner LPG forge. I tried some of the suggestions, i have turned up the gas, leaned off the mix, blocked off one of the openings and increased the heat. I get so far and the gas bottle freezes up after about half an hour.

Tried the couple of taps and the brush,flux and back in to heat, seemed promising but broke along the join when i tried to flatten the bar.


I'm going to see if i can get a local smith to teach me.

Was also wondering which side of Magnetic north i should stand 30 degrees from, you guys were pretty specific with the sqinting and tongue bit. I would have thought that it would have to be different in each hemisphere? :) FNQ and WI

[Frank Turley]

In reading some of the responses, I sense that there might be too much tippy tapping in our current world of smithing. The first few licks are relatively light depending on the thickness of the stock being welded. If you get cohesion, then you would normally start hitting harder at the same heat. It is OK to take repeated welding heats over the same area to complete a weld, but each heat should be a "sweating" welding heat; no sparks. The sparking heat tells you that you are at the incipient burning range. A huge shower of sparks tells you that you are burning the iron through excessive uncontrolled oxidation. In taking a heat, if you get a couple of sparks, you'll be all right...no big shower though.

I was at a workshop where the "dean of American blacksmiths," Francis Whitaker, was demonstrating. I asked him to demo a "T weld on the diagonal." He welded two flat bars together at about a 45 degree angle. When finished, he held it up and said, "Less is more. One heat." I still have that piece at my forge for a show-and-tell.

[Judson Yaggy]

I tried this new flux during a free moment on Friday. I made a cross out 2 pcs of 1/8 by 3/4" hot rolled a36. I was toward the end of my forging, and I wanted to try it in less than ideal conditions, so I didn't have a particularly clean or large fire. Brought the pcs to a low red heat, put a small dab of flux on each. Not much flux at all, and only one spot on one side of each piece. Returned to fire, brought the pieces back up to dull red, then to the anvil and tacked them into an X with one light blow from a small hammer. It stuck together well enough to be stuffed back into the coal without falling apart. One more small dab of flux on each side of the X, then three more light blows as soon as the piece got to an orange heat. Felt like a solid weld, but I really wanted to test it. So I did what you aren't supposed to do with a forge weld, I quenched it and then squared up the arms of the X by hammering them cold. The weld held. Then clamped the weld half in and half out of my vise and bent one arm down 90 degrees away from the weld. It finally started to peel open and inside it looked clean and shiny, no inclusions, just a good weld.

Thanks Brian for showing us this stuff at the New England Blacksmiths' meet last month!

[Wind Chapman]

Two questions. 1. At what type of heat did you apply this new flux before heating and welding?
2. When heating, are you using a gas or coal forge?

Stewart, it's all in the video I posted :~)

[Jason @ MacTalis Ironworks]

Just got back from the weekend SCA event here, and I had just gotten my bottle of Iron Mountain flux, so I had some good time to play with it, and I gotta say, I am sold on it. It is certainly giving a good initial tack weld at far cooler temperatures than I would expect. I have also been one of those guys with no real problems forge welding aside from the normal "trying to weld the god only knows what is in it alloy called A36", but when Brian speaks, I tend to pay attention. This stuff is awesome in it's ability to tack at the low temps, and it also seems to help with A36, as I succeeded with every weld I tried this weekend, usually, with Borax out of the box, I end up with a few failures. All of the welds held up to pretty hefty testing, and the few 90 degree lap welds I made held up in the vise, 2 of them actually tore at the steel and the weld remained intact (my definition of a structural weld). Needless to say, I am very impressed with it, and will be recommending it to everyone.

[brianbrazealblacksmith]

Glad to hear some are trying this. It does work like nothing I have ever seen before on mild steel or A36. My brother, Ed, just got off the phone with me after trying it, and he too can confirm that it wokrs like nothing he has ever seen. The ability to tack pieces together below a forge welding heat is an advantage that I would never had imagined. I know some people without much experience may not quite comprehend what has been discussed here, but for the experienced smith this is big news. I just got back from another conference in Texarkana with the 4 States Iron Munchers and they saw it in person and one person tried it during my demo and succeeded with his tack and weld. Keep your eyes open, we're going to see some new approaches open up with this new found ability.

[JimsShip]

I'm having trouble finding it, all the sites i've found are sold out. Anyone have a lead on where to get some?

[Thomas Dean]

If Brian still has it check with him. I got a bottle when I was there in April. Wow, that says something, everyone sold out!

[Judson Yaggy]

JimS- I ordered mine from this place in NH Meader Supply Corporation 23 Meaderboro Rd, Rochester NH 03867. Found their website thru google, ordered the old fashioned way (over the phone ;) ) Shipping was another $8 over catalog price. Will try it in the gas forge tomorrow.

[pike3e]

Does anyone think that this product would have any bennefits it making pattern welded steel?

[brianbrazealblacksmith]

Does anyone think that this product would have any bennefits it making pattern welded steel?

Every time I have shown this someone always asks that question. I don't think most people that develop patterns with layers of metal would want to throw some blotches of iron in the mix. Give it a try and show us what you come up with.

[ThomasPowers]

What he said! In general the powdered iron that makes this type of flux sticky also tends to blur layers in billets and so not a good idea. Since billet welding is generally one of the easier types of weld to do, most folks don't need "extra help".