Making consistant flat rings

[Iron Poet]

I've been practicing making flat forgewelded rings out of 1"x1/4" stock, and the forgewelding part is easy. The hard part is actually making them round instead of oval or square. I've tried to round them out on my horn but it seems like I'm expending a lot of energy on a substandard result.

Is there an easy way to make flat rings or do I just need to 'git gud'?

[jeremy k]

It's all the hand/eye coordination deal - how many have you made? One starts to get pretty consistent at the 75 mark.

[Iron Poet]

9 minutes ago, jeremy k said:

It's all the hand/eye coordination deal - how many have you made? One starts to get pretty consistent at the 75 mark.

3 or 4, it's for making cooking trivets

[JHCC]

Check out this video from Mark Aspery for tooling ideas. 

[jeremy k]

If you've only made 3 or 4 - then - yes you can expect to take a lot more time to get the final product as you wish. - Practice, Practice, Practice.

[Iron Poet]

I'm lazy and as such I try to find the most efficient way of doing things. But I suppose that sometimes practice is the only option

[Tubalcain2]

well, even if there is an easier way, practice can't hurt.

[jeremy k]

1 hour ago, Iron Poet said:

or do I just need to 'git gud'?

Yes

[ThomasPowers]

That's where a cone mandrel actually is a great tool!  Drop the ring on *hot* and run around it with a fairly light hammer, then pop it off, reheat and flatten. I've found a number of make do items, including the nicely tapered cone that covered the valve stem of  a large water valve that was scrapped by a local water treatment plant.  My favorite cone mandrel "stand in" was the penetrator tip of a ballistic missile.  Fellow showed up at Quad-State on year with a flat bed of them that had failed Q/A and sold them off very reasonable...

You really need a true round as large as the ring you are working.  For really large rings you will want a ring roller like the old wagon tyre rollers.

[Chris Comtois]

Bend it 'round a 6 inch (or whatever) diameter pipe?  I've collected loads of pipe scrap, old fire extinguishers and even a scrap oxygen cylinder (empty and opened at the time I acquired it) that I use to get pretty close to perfect circles.  You're bending it "the hard way" i.e. thick-wise, but I think it still might be easier than using your anvil horn. 

Lots of things can be anvils, if you look at them right!

[Glenn]

Bent the hard way, the inside of a ring thickens, where as the outside of the ring thins out. This makes a difference in some projects.

[arkie]

Make the ring out of round rod, shape it to size, then flatten with a hammer and flatter.  May need to make a few trial runs to get the ID, OD and thickness down pat.  That's a backwoods way to make a flat ring....

[evfreek]

The difficulty with making rings round is that it is really hard to bend a round shape in the contour of the ring.  Instead of trying to do that, flatten the ring.  Flattening is easy. Just hit the bend at its highest point, and it will collapse to being flat.  The trick is to find the part of the ring with the smallest radius.  In the above picture, this is at 10:00.  There is another small radius at about 7:00.  Place the small radius section on the anvil horn so that a small amount of daylight is showing, and give it a whack.  Note that this doesn't require a cone shaped horn, although it does help.  The shape of your anvil looks a little challenging.  it may be helpful to make a hardy with half a cone bent and welded out of plate.  Note that it doesn't have to be perfectly round if you are using the above technique.  Even a chamfered bar clamped down will work in a pinch.  If you have trouble finding the tight part of the contour, draw a circle in chalk on a piece of plate and compare with the circle.

[BIGGUNDOCTOR]

I would be looking at a jig, or making a ring roller. A Hossfeld style but much simpler 

 

[rockstar.esq]

This kind of thing explains why it takes rookies so long to make cheap stuff, and why experienced folks charge so much to do it right away.  Developing skill is like an investment that banks on time.

[ThomasPowers]

Also shows that precision costs: +/- a centimeter is very different than +/- a nanometer!

[Judson Yaggy]

To true a ring, try using 2 hammers one to tap with and the other to "back up" the work piece. Easier on a cone where the work can be horizontal and supported by the cone but doable on the horn as well.  To make them more consistently a short arc segment of the inside diameter tack welded to a plate or table with a pin welded on at the outside diameter makes a good bending jig.  

[beech]

On 12/15/2016 at 3:16 PM, rockstar.esq said:

 Developing skill is like an investment that banks on time.

Now ain't that the truth.

[Nick]

When I make flat rings I make a template from a manila folder, then transfer that with a sharpie to a big, flat aluminum plate I have (metal is better than wood for this, doesn't scorch).  As I work the bend into the flat stock I check it against the template, using the inside of the marker line.  It goes quickly and when done I only have to do a very minor amount of correction around the weld.

[Joel OF]

For the smaller diameter hoops/rings in this well cover I couldn't roll them as my ring roller is manual & not that strong & it would have killed me. 30mm x 6mm flat bar on edge.

I made jigs to form the smaller rings hot by rolling some flat bar, on the flat, welding them to my bench, then bending the hoops around that. Doesn't matter that the central hoops aren't complete, same principal. Arc welded, though.

[David Kailey]

just build a jig.......jig jig jig.