be careful where you buy your metal

PaulW · Post by **PaulW** » Wed Feb 08, 2012 4:03 pm

Good heads up. Pass it around
PaulW
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Hello All!
Recently I have purchased a good bit of 4130 tube. Here at Thunder Aviation we test every batch of material we will be using and have had some very disconcerting results. This particular batch came from a major supplier of aircraft products. Once it was unloaded we took several random samples and performed pull tests with shocking results. So we then pulled several more samples for x-ray. We received 4130 chrome moly with as many as 18 inclusions per inch! This is without a doubt junk material. We had a similar experience from a second major supplier and a nightmare issue with some 5052 aluminum that would barely weld. The problem with the chrome moly is by looking you would never have realized a problem. Without testing I wonder how
much of this material is out there flying around now?
My best advice folks is to require a supplier to certify country of origin when ordering such materials. And only accept materials from the US and Germany. We have found no issues with materials from these two countries.
Tom Parker
Thunder Aviation
http://thunderaviationengines.com

And another source

Its not only 4130, I had to scrap out a $3500 job because the material supplier
sold me some aluminum bar from China that had imperfections in an extrusion

This was flight hardware that is supposed to go on space flight equipment.
Domestic suppliers are getting their asses kicked and people buy whatever is cheapest.
So material suppliers are getting fed up

Its a careful game I have to play all the time, No different than buying shit from Walmart

Ya get what ya pay for

Wayne

ESHALLBETTER · Post by **ESHALLBETTER** » Thu Feb 09, 2012 6:04 am

Thank you for this post.

kylesgorter · Post by **kylesgorter** » Sun Feb 26, 2012 8:20 am

Just wanted to add here that all the steel available from any local provider here is from korea. At my work we dont even have the option of buying american steel unless we have it shipped from out of state.

Since we have been using this korean steel I havent noticed any major difference in how it welds but we have had an issue almost everytime we try to have something powdercoated. our coater is always complaining that he has to do it over usually a couple times because "there's something in the steel" Im not sure if the steel is the cause in that respect but it was never a problem before when we could get domestic product

PaulW · Post by **PaulW** » Sun Feb 26, 2012 8:40 am

Obviously the metal you are using is NOT per the US standards.
If you are doing stressed tube members you sholud be doing sample x-ray per the original post. For non stressed members just use the cheap stuff. It probably is cheaper to pay the shipping at least for the critical members. Or figure the tradeoff between the high cost of shipping and a DIY drive.
Dont fudge on cheap metal on critical parts.
PaulW
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kylesgorter wrote:Just wanted to add here that all the steel available from any local provider here is from korea. At my work we dont even have the option of buying american steel unless we have it shipped from out of state.

Since we have been using this korean steel I havent noticed any major difference in how it welds but we have had an issue almost everytime we try to have something powdercoated. our coater is always complaining that he has to do it over usually a couple times because "there's something in the steel" Im not sure if the steel is the cause in that respect but it was never a problem before when we could get domestic product

ESHALLBETTER · Post by **ESHALLBETTER** » Sun Feb 26, 2012 7:45 pm

kylesgorter wrote:Just wanted to add here that all the steel available from any local provider here is from korea. At my work we dont even have the option of buying american steel unless we have it shipped from out of state.

Since we have been using this korean steel I havent noticed any major difference in how it welds but we have had an issue almost everytime we try to have something powdercoated. our coater is always complaining that he has to do it over usually a couple times because "there's something in the steel" Im not sure if the steel is the cause in that respect but it was never a problem before when we could get domestic product

I would look for a new supplier. Many of the jobs I do require material to meet ARRA (buy American) requirements. I am in Minnesota and use a supplier in Illinois, and they are very competitive, I can even get it on a truck for next day delivery most of the time.

kylesgorter · Post by **kylesgorter** » Tue Feb 28, 2012 7:44 pm

At our place our work is 80% trailers 20% trucks. Im not building airplanes or space shuttles or anything. We have four different suppliers for steel and usually quote them all and order from whoever has the best price. The fact that NONE of them can supply American made steel is what makes me a bit angry. Just wanted to throw in my experience with this.

Also, tried to order a marlin crawler bumper for a customer about 2 months ago. Spoke directly with the owner of marlin. They apprently havent built a single bumper in a year because they cant get american steel

philofab · Post by **philofab** » Tue Feb 28, 2012 8:49 pm

I started noticing tube kinking instead of bending years ago.... Same machines, same person working the machine, different results. I now have to anneal some stuff before I work with it.

kylesgorter · Post by **kylesgorter** » Tue Feb 28, 2012 9:23 pm

anneal? tell me more...

Ive also felt Ive noticed tube flattening more on tighter bends given same material but never any full blown kinking. Never really seemed to be a big deal and it has always still looked good in the end but I think I can say Ive noticed a change. Like I said, no change in how it welds as far as I can tell but we also use co2 instead of c25 on the mig machines and I rarely do any tig welding so maybe i cant tell.

My boss always makes comments when he sees the printing on some of the sticks that say KOREA or HUYNDAI

philofab · Post by **philofab** » Tue Feb 28, 2012 11:38 pm

If you take metal, heat it, and put it in water/oil you harden it or quench it.

If you take metal, heat it, and put it in kitty litter or let it cool naturally you anneal it. Annealed metal bends very easily. Quenched/hardened metal does not.

kylesgorter · Post by **kylesgorter** » Sat Mar 03, 2012 3:00 pm

I see. I was over-thinking this. i was imagining some sort of extensive heating/cooling process with tools Id never own. But yes i see what you are saying. ive only once ever heated tube to help bend it when doing some 2x0.250 dom with his manual jd2 bender and then I just got it pretty hot, let it cool a little then tossed it in the bender (it was only 15deg bend). He actually needed one more bend and did it when I wasnt around and without heating it and the top plate on his bender cracked around the pin and let go so obviously heating it did help a lot. if I run into any issues at work (we dont do a lot of bending anyways) Ill keep this info in mind.

I wish there was some way one could see how the grain structure in the metal changes and flows as its heated and cools that would be interesting to me. Also to see side by side that same process with imported v. domestic material

philofab · Post by **philofab** » Sat Mar 03, 2012 3:31 pm

If you ever have a chance to take a Jewelry or Blacksmith class, do it. You will learn a ton about working with metal.

kylesgorter · Post by **kylesgorter** » Sat Mar 10, 2012 12:03 pm

philofab wrote:If you ever have a chance to take a Jewelry or Blacksmith class, do it. You will learn a ton about working with metal.

thanks ill look into that. I actually applied some of that info at work this week with good results.

Oh yeah and we got an order of 304L on thursday all of which has "MADE IN USA" printed on it

78Class3 · Post by **78Class3** » Mon Mar 19, 2012 3:55 am

Just out of curiosity, what is the approx going rate for CroMo tubing right now.

Ive been quoted for a 3' length of 1.5 x .188 wall tube at around $30 from one place

and over $60 from two others.

ESHALLBETTER · Post by **ESHALLBETTER** » Mon Mar 19, 2012 10:43 am

Last price I got for 1.5od x .120 wall was about 9.50/ft.