# Seeking Guidance on Bending Project



## auto.pilot (Feb 19, 2017)

This small steel part is from a 1930's snare drum.  There are 16 of them on each drum.  I'd like to replicate them as near as possible.  Ultimately, I'd like to make many more than 16, perhaps several hundred.  1/8 by 5/8 bar stock is available, and cutting/drilling to size is simple enough.  However, I could use some guidance on the bending process.   I have a 20 ton H frame shop press (hydraulic bottle jack), but don't have a brake.  I also have a 3 ton arbor press.  Some questions:  1) Is this a job for the arbor press? 2) will I need goose neck dies for the sharp bends? 3)  what method should be used for the curved bend?  4) given that I am new to this...  what else do I need to consider?   

Thanks in advance.


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## Mister Ed (Feb 20, 2017)

My thoughts, based on equipment I have (not doing you much good), would be to bend them on my little Hossfeld bender. It would probably take a little thinking and making a die for the curve ... but I think a guy could figure it out. That curve and skinny bend would be first. Either a die to form that in a single bend or bend the curve, then reposition and put in the angle. The other two bends are easy peasy. 

Something else to think about, the profile of that skinny angle and curve is not dissimilar to some vice jaws. I was bending a piece of sheet in the vice last night and would have ended up with similar profile had I kept going past 90*. Build a little jig/block to match the profile. Bend a 90 to start and then place in the jig (in the vice) to bend the rest of the way. You could put the 'tail' of the piece in a piece of 3/4" pipe for some leverage while bending the curve around your die. Then tackle the two 90s and trim to size.


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## RJSakowski (Feb 20, 2017)

That short foot is going to be nasty because it's so short and because of the holes.  Making clean bends with that small an inside radius is difficult.  You will want to have full support of the part as you progress through the various bends. 

If I were making the part, I would make a couple of forms to secure the part and define the bend.  I would make the 90º bends on the feet first because it is difficult to make that sharp a bend.  At that point, I would leave additional stock on either end.  This will give you a "Z" shaped part. I would then use a jig to form the last 90º bend.  Next, I would shape the ends and drill the holes.  Finally, I would use another another jig to create the curved bend.

The bending process may be easier done hot, i.e. a bright red heat.


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## dennys502 (Feb 20, 2017)

I'm not sure what you have for equipment. This is a simple form tool. Just to give you an idea. It would need a roller to pull the material around the post. The pin would 
go through the hole in the part for location and holding the piece.  This is not the way I would make it just how it can be done. The other forms would be done first and the last 2 holes drilled afterward.  From your picture it looks like there is breakage in the hole indicating they were punched and the hole doesn't look deformed so it would have been punched after forming.


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## 12bolts (Feb 20, 2017)

I would do it in the H frame press with a couple of dies. Shape the rounded ends on your stock but dont drill any holes yet.



This being the lower die to form the 1st 90* bend, and the curve.                    After pressing the upper die, ^  in to shape, whilst it is still under pressure use a hammer to start to fold the ears over. Then release the press, insert a flat plate and press that down on the ears to flatten them. You may need to adjust the dies to allow you to get over 90* to allow for spring back unless you do them hot. You will need to slide the upper die out laterally. Then drill your holes. It will take a couple of goes to get your stock length correct and the correct placement for overhang at each end.

Cheers Phil


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## auto.pilot (Feb 20, 2017)

Wow, thanks for all the excellent replies.  Quite impressed that two different responders would take the time to draw some ideas.  This give me plenty to consider.  Thanks so much for the advice!

Jim


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## auto.pilot (Feb 20, 2017)

Follow up question.  What material is suggested for the dies?

Thanks


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## 12bolts (Feb 20, 2017)

Ideally, (because you say you want to make lots), tool steel. Something easily obtained would be D2 or S7. But there are more knowledgeable people here who could probably pull a dozen different metals out of their heads.

Cheers Phil


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## dennys502 (Feb 20, 2017)

I usually use A2 tool steel. D2 is good but work hardens very easily.
Here are a couple of examples - one is a little die set to do 2 of the bends first and the second a roll form for the last bend.


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## auto.pilot (Feb 20, 2017)

I am simply blown away by the quality of replies.  Thank you!


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## dennys502 (Feb 20, 2017)

Glad I can help guide you. I had a small manufacturing company with my father in law in the 70's and 80's - I did all the tool and die work and made some specialty machines for some of the things we made. I've always liked designing and building things and its nice to pass along some of the things I have learned over the years. I never stop learning - always something I haven't seen before.


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## Big Bob (Feb 25, 2017)

Do not forget black smithing techniques an addition to machining, heat hoy enough to easily bend, using fixture if necessary. You can rehardem/temper if needed also.
Bob


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## LucknowKen (Feb 25, 2017)

Very interesting thread.
Nice writeup.
lk


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## BobSchu (Feb 25, 2017)

Great ideas, but looking at this part and the times I've attempted such a project I would say this won't work properly without heating the part just for bending. If you bend these cold, you will most likely get a weak point at least and at worst a crack at the reverse bend. Also, the effort bending the parts once red hot will be much less and the results will be cleaner and you won't have to worry so much about spring back after the bend. 

Bob


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## auto.pilot (Feb 25, 2017)

I bought a small vice brake from Grizzly just to see if i could get satisfactory results. I certainlt can't make hundreds of the part using this method...

I started with 1 inch by 1/8 bar stock, cut to 5/8 wide. The result is slightly wider than 5/8.  The small tab is slightly too long and my holes are slightly off center. I have never bent metal before, so this learning experience was quite an eye opener. Bending was somewhat easier than expected. Centering and drilling holes was harder.  Work continues... more posts to follow as I seek consistent and faster methods.  

Thanks!


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## auto.pilot (Feb 25, 2017)

One more


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## Big Bob (Feb 25, 2017)

Hole geometry and location can distort when parts are bent, so if critical, consider drilling after bends


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## T Bredehoft (Feb 25, 2017)

A milling machine and a jig to locate the parts would make drilling a snap. Nice job of bending, BTW.


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## auto.pilot (Feb 26, 2017)

McMaster Carr carries 1/8 by 5/8 bar stock in both low carbon steel and stainless.  I placed an order for both today.  When polished, stainless looks a lot like vintage chrome or nickel plating.  Finding a plating company for small jobs has always been a challenge, so I may use stainless.  

Options for the rounded ends: 
1)  At the shop, someone suggested that I use the Tormach to cut the rounded ends on the bar stock.  The idea was to cut each piece slightly larger than the finished length (approximately 4 inches), then punch the holes.  Several pieces of bar stock would then be bolted to a jig.  Thereafter, the rounded ends would be cut on the Tormach.  I am concerned about lining everything up repeatedly and about punching the holes before bending.  The hole spacing needs to be relatively precise and the holes need to be round.  
2)  The shop has a Jet 20 inch 2 HP disc grinder which sands bar stock very quickly!  It took literally seconds to freehand each rounded end on this piece.I am considering making some sort of jig that could be mounted to the disc grinder table to 'swing' the bar stock back and forth at the required diameter.   Link to Jet Disc Grinder:  https://www.jettoolstore.com/collec.../jet-577010-j-4421-2-20-220v-disc-sander-3-ph
3)  I also have access to a Jet mill and found this video....  



4)  I have considered but rejected the water jet, primarily because my original piece was likely made from bar stock.  I'm not sure it can be seen in the pictures, but the edges are rounded along the length, so I'm guessing guessing it started as bar stock.  
5)  Impossible to tell from the pictures, but it appears that just the rounded ends were sheared off.  Does anyone make a metal punch/shear that would only cut the rounded ends from my bar stock?  

Thanks for all of the replies thus far and any additional thoughts.  This forum is great!

Jim


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## brino (Feb 26, 2017)

Hey @auto.pilot

If you haven't seen it look at @BGHansen 's excellent post here:
http://hobby-machinist.com/threads/...in-your-shop-today.14637/page-311#post-463705

Sure he's making different shaped parts, but many of the issues are the same, and many ideas should be transferable.

-brino


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## auto.pilot (Feb 26, 2017)

Brino--- thanks for the link.  That's some incredible work he's doing.  A dream for me really.


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## dennys502 (Feb 26, 2017)

You could make a little die like this - it would put the radius on and cut to length at the same time.
 About 6.25 tons to punch. You could also add one hole at the same time.


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## auto.pilot (Feb 26, 2017)

Thank you!  your replies have been very helpful.  

Jim


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## Kiwi (Feb 27, 2017)

well plenty of options there to try the only change would be to make them out of stainless steel and polish them rather than chrome plate I know it will it harder to bend but you also could reduce the thickness to counter the bending  moments and still retain the strength


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## auto.pilot (Mar 3, 2017)

I found a place locally that will harden the A2 bending die and roll form tool at a cost of $40.  That's good news because I have no way to do it myself!

Thanks

Jim


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## Cheeseking (Mar 3, 2017)

Nice job on the prototypes so far.    Just my .02 on material choice - drilling and deburring the holes in ss wont be fun.  Talk about smoking drill bits.  Polishing the ss is possible but labor intensive.   I would rather fabricate from crs then send a whole batch to the platers and be done.   
For bending clips like that in relatively small volume you might consider picking up a used 1a DiAcro bender?


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## auto.pilot (Apr 12, 2017)

My progress was delayed by some time out of town.  I considered the project and my abilities and decided to make this dedicated bending tool.  So far I have one small die that bends the sharp angle and curve. I've got some fine-tuning to do but I am happy with progress so far.  Actually this is the first tool I have ever made in my life so I am beyond happy! The bends shown here are just samples to see if it would even work.  The last picture is s plywood prototype which I cut on a laser cutter. It actually bent one piece of eighth inch thick aluminum before the die disintegrated.


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## Cheeseking (Apr 12, 2017)

Nice job making a little bender.  
If you plan to do much other custom bending and want something universal, find a nice one of these...
Wonderful little tools for that kind of work.  I believe it a 1A diacro



I


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## auto.pilot (Apr 12, 2017)

Now that I understand the capabilities, I would love to own a Diacro bender.  I just can't justify the cost. My cost to make this one was less than $50.


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## jamby (Apr 13, 2017)

Great thread.   I've learned more here then in the last 5 years.

Jim


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## scwhite (Jun 4, 2017)

auto.pilot said:


> This small steel part is from a 1930's snare drum.  There are 16 of them on each drum.  I'd like to replicate them as near as possible.  Ultimately, I'd like to make many more than 16, perhaps several hundred.  1/8 by 5/8 bar stock is available, and cutting/drilling to size is simple enough.  However, I could use some guidance on the bending process.   I have a 20 ton H frame shop press (hydraulic bottle jack), but don't have a brake.  I also have a 3 ton arbor press.  Some questions:  1) Is this a job for the arbor press? 2) will I need goose neck dies for the sharp bends? 3)  what method should be used for the curved bend?  4) given that I am new to this...  what else do I need to consider?
> 
> Thanks in advance.
> 
> ...


My thought is those parts was most likely bent 
Red hot


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## scwhite (Jun 4, 2017)

Cheeseking said:


> Nice job on the prototypes so far.    Just my .02 on material choice - drilling and deburring the holes in ss wont be fun.  Talk about smoking drill bits.  Polishing the ss is possible but labor intensive.   I would rather fabricate from crs then send a whole batch to the platers and be done.
> For bending clips like that in relatively small volume you might consider picking up a used 1a DiAcro


I would use HRS not CRS
CRS tends to crack in a sharp bend unless you get it red hot first .
      HRS bends easier and is  less appt to crack


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