Sign in to follow this  
Jon Lewman

Tongs Breaking

Recommended Posts

So my first set of Tongs broke while punching the hole. I figured because I used a center punch instead of a drift. 

Tonight I cut the broken end off and rebuilt it, drilled the hokes and pinned. Was happy with the results. 

Then when I tried to use them, about 10 hits in and the jaw snapped off. 

Been using sicker rods. I have also had problems drawing it down. Two different prices I squared up, then when I tried drawing it the end split into 3 pieces?  

Any ideas what I am doing wrong? 

 

20150924_202705.jpg

20150924_203256.jpg

Share this post


Link to post
Share on other sites

What are you using for stock? How thin did you make the boss, did you quench the jaws...

dosnt look like it broke threw the rivet hole so why do you think that using a center punch was the isue?

Getting the boss to thin, making a sharp transition at the jaws into the boss (this is why we round the edges of anvils) and quenching spring stock can all lead to failers

Share this post


Link to post
Share on other sites

Did not quench them. 

Using 5/8 suckered rod. 

The first one broke at the rivet hole whIle punching,  when I hit it, I saw it rip apart from the punch. I figured it was because the center punch spreads and basically rips whereas a drift shears. 

So I guess it must be that I left a sharp corner? 

Maybe I should've normalized after working? 

And why did the material split when I tried drawing it down?

 

Share this post


Link to post
Share on other sites

Your on the right track. If you make your centrr punch very blunt. Not like flat, but make the point very shallow it will work better butt heat is your friend. We want hot, but we need falling heat on the punch, we want to move metal, wile cooling the thin slug against the anvil. 

If it is too hot the slug will heat back up when you flip it over, find the dark spot and drive it back. The cool slug will shear out. To mahe the hole larger, or to a perticular size or just strait sided, take a heat and use a drift. 

Now , one must use radiused tools to set any project, or it creats stress rizers, and that is a place for a crack to form. 

Lastly dont make things too thin, especialy close to the boss as the stress their is high. 

Share this post


Link to post
Share on other sites

Now that I look at my pictures. The jaw that broke looks like it was cracked. The corners of my "anvil" are sharp, and I did have a pretty sharp corner. Might need a bit if a radius there. 

Here is my awesome anvil and my cutting tool...

20150924_202134.jpg

20150924_202140.jpg

That old Mattox actually cuts really well. 

Share this post


Link to post
Share on other sites

Learn with mild steel, they make good tongs and are more forgiving for when you are starting out and are afraid to work when Hot.

You didn't fail, You had a lesson.

Neil

Share this post


Link to post
Share on other sites

I have no experience of sucker rod - they do not exist here but looking at the pictures I get a feeling that the stock has been overheated. Silly questions but did you get sparks at some time during the process?

Göte

Share this post


Link to post
Share on other sites

Learn with mild steel, they make good tongs and are more forgiving for when you are starting out and are afraid to work when Hot.

You didn't fail, You had a lesson.

Neil

afraid to work hot?

I havea spot o my belly that says it was hot...Lol

I will try agsin with mild steel. Not sure of sucker rod properties? 

I have no experience of sucker rod - they do not exist here but looking at the pictures I get a feeling that the stock has been overheated. Silly questions but did you get sparks at some time during the process?

Göte

hmmm, not sparks. I did have those pretty little dancing sparkly things a few times when pulling out of fire?

Share this post


Link to post
Share on other sites

Sucker rod is simular to spring (4060) Some smiths like spring as it alowes a lighter tong to do the job, but quenching a hot tong is then a no no. High and medium carbon steels burn at a lower temp than mild steel, no more than low yello for mild steel, high orenge for high

Share this post


Link to post
Share on other sites

I would bet on a combo of High carbon steel worked to cold and sharp corners putting stress cracks in the steel at the jaw draw down. Sparklers bad, hammering cold steel bad, sharp corners bad, experience priceless.

 

Russell

Share this post


Link to post
Share on other sites

 

hmmm, not sparks. I did have those pretty little dancing sparkly things a few times when pulling out of fire?

That was the cause. the steel burns meaning that it oxidizes in the grain. The internal cohesion of the material is gone. you have turned a plastic hot material into a brittle junk that can only be used by stell wrks as scrap.

 .   

Share this post


Link to post
Share on other sites

Played with some more. One piece worked great, the next piece as soon as I hit it split into 3 pieces. 

Getting some different materials. 

Guess I need beginner steel, lol. 

Share this post


Link to post
Share on other sites

Sucker rod tends to be pretty good for tongs. Most of the tongs I've made are sucker rod. It's generally not above 40 points of carbon. That said, it's still a "junkyard steel" and my sucker rod may be a rather different alloy from yours.

Share this post


Link to post
Share on other sites

Sucker rod tends to be pretty good for tongs. Most of the tongs I've made are sucker rod. It's generally not above 40 points of carbon. That said, it's still a "junkyard steel" and my sucker rod may be a rather different alloy from yours.

Hate to differ with you, but sucker rods are not "junkyard steel".  They are made to very exacting standards, usually API, and, yes, they can be different alloys.  You don't use junkyard steel in a pumping well, or you'll have a fishing job to recover the lost pump and parted rods in the hole.....

Search oil field supply sites for sucker rod specs to see how they are made.

Share this post


Link to post
Share on other sites

I think in this case, you are both right. Tho sucker rod is a known steel (sinply google the manufacture and their websites generaly tell you how the interpret the markings) we are salvaging it and reperosing a used, now scrap pice of material. But I will say, beats the heck out of A36 or rebar for consitancy, if its not a bit of a bugger to get to move under a hammer

Share this post


Link to post
Share on other sites

arkie: I agree with you (and Charles). Sucker rods are made of various good steels with fairly tight specs. What I mean by "junkyard steel" is that it's an unknown steel (when salvaged without specs). Same with spring steels. I think most people in our hobby / trade use the "junkyard steel" label to mean "unknown" not "poor quality". I certainly do.

Share this post


Link to post
Share on other sites

Eric, you have a good understanding of the sucker rod question...

Charles had a good point...check the sucker rod(s) to see if there are any identifying characters or markings.  That would move them from the category of unknown scrap to an identifiable steel.  They will usually be on the box or pin end.  The manufacturer might be able to give you the composition (if they are still in business, of course).

Happy forging!

Share this post


Link to post
Share on other sites

I've got a set of tongs that I made from NASCAR axle steel.  They don't call it high tuff for nothing.  The tongs are nice and light with a fair amount of spring to them.  I did crack one of the bosses while punching the hole, I let it get too cold.  After grinding the crack and welding it the repair is working just fine. Like said earlier, high alloy steels need to be hot to forge.

Share this post


Link to post
Share on other sites

Sounds cool to me, "NASCAR Axle Tongs" aught to be pretty darned marketable especially if you can tag the driver's name on a pair. Maybe instead of an upset ball on the ends of the reins racing wheels and tires?

You might be able to find some videos of Grant Sarver making tongs, he had an efficient set up and shared his techniques.

Frosty The Lucky.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this