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.