forging non 90 degree angles

[dognose]

I imagine this information is somewhere on this site, but as usual, I'm unable to locate it. I'm attempting to forge a series of non 90 degree angles in square and or rectangular stock. I know the process for making 90 degree angles, but in my mind, it doesn't apply once you go above or below the right angle. My brain immediately thinks that a top and bottom swage is the way to go, but with a dozen or more different angles, that would be a lot of tooling and as far as I know, an adjustable angle swage doesn't exist. So, I'm posing the question, how does one go about forging clean, sharp angles without changing the dimension of the parent stock? I'm hoping my pea sized brain is overlooking something quite simple. I've included an image of a quick sketch of what I have in mind. Thanks

[Glenn]

how does one go about forging clean, sharp angles without changing the dimension of the parent stock?

 

If you bend parent stock the inside grows thicker as it has a shorter length to travel, the outside grows thiner as it has a longer length to travel, and the center line of the stock should remain constant. If all things were perfect you could move the inside material to the outside with forging. I would think in the real world that you have to upset the stock enough to give the angle enough mass to match the parent stock after forging. This would become more important with a sharp corner on the inside and outside of the angle.

 

 

 

as far as I know, an adjustable angle swage doesn't exist.

It will as soon as you make one (grin) Please post the adjustable swage and photos to the forum  Until then I would think you would eyeball the angle and do a final check against the known angle or drawing on the work table.

[dognose]

Although I agree with all you said, I'm still not sure what I'm hammering against? Are you suggesting it's the same process as forging a 90 as it is for any other angle? Just eye ball it while working, the check it against the drawing at the end of every heat?  As for upsetting, it seems as though with each heat, that's the process that's already going on (driving the ends into the angle). If i were to pre-upset, I would think I'd end up with a larger mass at the angle's bend than the rest of the parent stock when done.....

[Fe-Wood]

Obviously it will take practice! It is just like forging an upset square corner only you are not making it square. All the same rules apply. Mark the centers as Glenn suggested (the center of the angle in the center of the stock on edge as that is the constant) forge with cycling blows as you would an upset corner, just don't take it all the way to 90 degrees. The short lenght between corners will be fun to sort out but doable...

[yahoo2]

All the old machinery I work on have corners that are welded

 

Mark Aspery has a video called "forge welded square corner on a flat bar" that explains it pretty clearly, more oblique or acute angles just takes a bit more tweaking of the angles and material upset to get it right.

 

He also does a bend and upset technique in the video "upset corners for the national grill" I have not tried this with an unradiused bend as I am usually trying to avoid cracks forming and I am more confident with an upset curve.

[doc]

Create a normal 90* bend to get your sharp corner. Then open it up to create your less than 90 corner. It will take a little tweaking to bring it where you want but it is the quickest and simplest way. 

[anvil]

if you can forge a rt angle, you can do any angle. the process is the same.

there are a number of ways to forge -an angle- all require an upset, as Glen said. some upset first, I upset whilst forging my angle. my formula is 12 the thickness added to each side of the bend. this works for most any angle. i check this each forging-both sides of the bend. i made a simple angle finder, set my angle and check it each heat. this way i can forge any angle to length quickly.

i can do this totally in the forge and teach it that way. however these are really nice to do with a torch. i make my initial bend in the forge, then refine with a "localized heat" with my torch. sweet.

By adding 12 the thickness of material to each side for the upset gives a small radius to the inside. if you want a larger radius, just increase the amount for upset from 12 to say 34 the thickness of material. it adds a cool design element for your bag of tricks.

[JNewman]

if you can forge a rt angle, you can do any angle. the process is the same.

there are a number of ways to forge -an angle- all require an upset, as Glen said. some upset first, I upset whilst forging my angle. my formula is 12 the thickness added to each side of the bend. this works for most any angle. i check this each forging-both sides of the bend. i made a simple angle finder, set my angle and check it each heat. this way i can forge any angle to length quickly.

i can do this totally in the forge and teach it that way. however these are really nice to do with a torch. i make my initial bend in the forge, then refine with a "localized heat" with my torch. sweet.

By adding 12 the thickness of material to each side for the upset gives a small radius to the inside. if you want a larger radius, just increase the amount for upset from 12 to say 34 the thickness of material. it adds a cool design element for your bag of tricks.

There is a way to forge a square outside corner that I have used quite a few times that does not require an upset and can be easier than upsetting.  Start with heavier stock and draw it down either side leaving a heavy section.  If you fuller either side of the corner leaving a point where your corner will be formed, the point makes a nice outside of the corner.  

 

Having extra material in a corner is always better than not having enough.  You can draw it back out unless you have already forged a feature on the ends in which case you can leave the corner heavy in the other plane, or  file or grind away material.  

[MLMartin]

I will often take a very short heat at the bend area while the bar is strait then give it a good upset. Take a second heat and bend to the desired angle. Take another short heat right at the bend and place the bar in a vice with the bend point up and the bar clamped with both ends in the vice while the bend is above the vice jaws. Then you can use a light hammer and peen and hammer the upset area into a crisp point.

[joshua.M]

Look up the Habbermann Bend, I was taught the technique by Brian Brazeal, it allows you to set the inside and outside angles without the need for upsetting, and in my opinion is quite pleasing to the eye

[Judson Yaggy]

What is the final product you are producing?  Tool, art, architectural, etc?

 

I will strongly recommend looking into Joshua's suggestion of the Habbermann bend.  You could bend and upset a 90 degree corner then back it off and repeat if you need to maintain a true square cross section, or you could cut electric weld and grind square bar for the same effect.

 

But if you want crisp corners in one plane and obvious hand forged not cast or cut and welded when looked at from another angle read up on the Habbermann techniques.  

[Jim Coke]

Greetings Dognose,     Not familiar with the Habbermann techniques...

 

With the slight bends as per your picture ..  Do a modest upset at the point of bend...  Bend...   What you should end up with is a small radius on the inside and enough material on the bulk of the bend to forge the outside to taste... the inside with the radius you could file to meet the angle..   Good luck

 

Forge on and make beautiful things

Jim

[dognose]

Thanks for all the pointers, I'll look into all of them. To answer Judson's question, The angles will be incorporated into an architectural element over a wood gate I made (see pic). I find it sort of humorous that this detail could be done with my band saw and welder quite easily, yet I would be unhappy with the results and consider myself a failure for having done so. I find while working, somewhere in the back of my mind, the quality/complexity of work smiths of yesteryear were able to accomplish without modern conveniences. I guess everybody has drawn there own line in the sand for what's exceptable and what's not. For example, I have no problem using my electric drill press for riveting, My MIG welder for making tools, an angle grinder to save time before filing or my horizontal bandsaw when a hacksaw would do the job. I guess while I'm still just learning, I don't like to see any non-forged elements in my work and while sometimes it's quite frustrating, I enjoy the challenge. Hopefully in the near future I'll be posting a pic of the finished project. Thanks for the advice, I look forward to trying your ideas.

[yahoo2]

Yep, you make a very good point there, I could never see the value in calculating and forging to length when it was easier to trim the ends of the piece afterwards. Now I see it as good practice because there have been times when I have needed that skill on a more complex job when I have had to finish the ends first.

 

I should have a go at the bend then upset version myself, now that I have watched the video half a dozen times it doesn't look as tricky as I thought.

 

And forming a cone, I haven't tried that yet.

[Eddie Mullins]

Just wanted to say thanks to the contributors of this thread, I didn't ask the question but have learned none the same.