Canister Weld failure - What might have been my mistake???

[Kayakersteve]

Started with mild tube 3x3 Coated with white out - Added 1084 powder and 1/2" ball bearings - Pressed well and billet stayed separated from tube as planned. Looked so so when first out of canister, but was able to recover it or so I thought. As I began to draw out, it quickly became clear I had a failure that was not recoverable. Now the question is what might I have done wrong on my first attempt at this? My guess is it has to do with the ball bearings -- they were purchased from Amazon....could they have contained junk steel? The billet has a bronze look to it making me think some junk steel or cast something was present. Any thoughts????

 

[stabber]

Wow, The glowing Billet looks good
Was everything nice and Clean?
Maybe Temperature was the issue
Or as you said, Them Amazon Bearings but the Billet still should have held together

 

[Rudy Joly]

Not enough heat/soak time ?
The powder looks all crumbly down in the large crack and maybe a bearing poking through indicating the can may not have been soaked (too cold) through when pressed. Just a guess from the pics.

Rudy

 

[Kayakersteve]

Everything was clean - The powder was made for this and the bearings were brand new - They had light coat of oil on them which would just burn off and should not affect the weld. The brownish color to the billet makes me think other impurities were present, presumable from the bearings. Was my first attempt at canister welding, so I will try again with different bearings. Will also press a little more before removing from canister.

 

[Kayakersteve]

I thought maybe more soak time, but was able to get a pretty nice looking billet after tweaking a little once pout of the canister. The cracks became apparent as soon as I started to draw it out.

 

[Kayakersteve]

Bearings were these: 1/2 inch Diameter Chrome Steel Bearing Balls G25 Ball Bearings VXB Brand

 

[Rudy Joly]

Without enough heat to weld the powder to the bearings, it would cause the powder to move around the relatively cooler bearings causing the billet to crack around them. What type of ball bearings were used ? If stainless, they'd need more temp than the powder.

Rudy

 

[Rudy Joly]

You answered my question while I was typing (slowly).lol
If the bearings were chrome plated, that may be the problem. I searched for ball bearings recently on e-bay and was surprised at all the different compositions there are. Definitely required some homework, settled on plain 52100 bearings for welding.

Rudy

 

[Kayakersteve]

i wondered about the chrome - will try 52100 next - thanks.

 

[Kayakersteve]

@Rudy - Where did you purchase your bearings from?
.

 

[Bruce Bump]

I'd like to see the dies you used in your press. They need to be squaring dies so they will press from all 4 sides at once. Also suspect the bearings were stainless steel. you should always etch the bearings to be sure they are not stainless.
Another thing is compression and heat. The can needs to be soaked at 2300f for several minutes. I've always said that if you think its ready go in and have a cup of coffee before you squeeze it. All powder needs to be compressed quite a bit. About 30% would do it. If the canister isn't constructed properly it can get air inside as you are squeezing it down. Be sure the canister ends are inside the can and welded air tight and not just capped on welded around the edges. This way the end puckers out like a dome instead of pops off.
Some say to leave a small hole for gases to escape, I say don't put anything flammable in the can to create gasses. There will be no ballooning if there is nothing flammable in there. Clean the ball bearings of any oils. The brownish looks like something was burning inside the can.
Don't draw it out cold either. Keep it at welding heat while drawing out. Just a very thin film of flux when it that hot will prevent decarb and micro cracks.
Hope any of this makes sense.

 

[Kayakersteve]

Steel must be garbage

I took that cracked billet back to shop ground into cracks, heated, fluxed, then brought up to a white heat - Squished the crap out of again on the press. They still have multiple cracks everywhere. What would be the brownish coloring? I think that has something to do with the failure???

 

[Kayakersteve]

Thanks Bruce - This was first attempt and I am learning a lot. Will try again and keep posted. Also, don't have squaring dies, but will soon

 

[Rudy Joly]

I'd listen to Bruce, he's THE man.

As for the bearings.....
I know they came from e-bay, I must of looked through a few thousand listings that day. I got a bag of 3/8" plain 52100 steel balls...not chromed. I dropped one in my dip bucket and it rusted up overnite on the bench.

Rudy

 

[Kayakersteve]

excellent - thanks Rudy....You guys are great.

 

[Kayakersteve]

Squaring Dies Made

Bruce - Have made Squaring dies, but still working on the mount for securing them. What do you think so far?

 

[Bruce Bump]

Steve, those look pretty good. I would cut down another set of angle irons and slide them in under those and weld both ends solid. that would ensure they won't distort or collapse with heavy pressure.
You will need a couple more sets just like them to re-square billets after size reduction.

 

[Fred Rowe]

Powder especially, needs the squaring dies in order to weld properly.
For me, ball bearings are the hardest thing to forge weld. I've never had great luck with them ever with the right set up.

Fred

 

[Bruce Bump]

Bearings are very solid and powder is very soft and fluffy (for lack of a better term) It takes allot of compression to make powder weld and the bearings may be holding it back from compressing especially if its not soaked at welding heat and squeezed from all four sides at once. You only have 5 seconds to make the weld so ya gotta be fast and re-heat again for another weld. The 4 sides allow you to do that all in the crucial first welds. I like to weld about 5 times before drawing it out. You can feel it firm up when its welded, until then it feels soft and gushy (a technical term) The canister may be flopping around if you put stainless foil inside. I've been using "white out" from Staples lately. It works better as it doesn't trap stainless foil in the contents.

 

[Kayakersteve]

Thanks again for comments - I used white out and even though my billet was not perfect, it dropped right out once I pealed canister open. Will re-enforce as suggested and am working on next size smaller for progression. Do you go to regular (?name) dies once billet removed from canister for drawing it out??