I do understand that you want to keep a copy of your old site - but don't really understand why you allow this site to be indexed by Google? (robots.txt allows full indexing).
The reason you kept it seems a bit off - redirects are made on domainnames. So keeping the site accessible under the IP address will not help you to check if the redirects are properly working.
Why would you need to install Wordpress on the old server - redirects are made in the htacess file. Absolutely no need to do this via Wordpress. Check here or just google it (if you also changed the url's the redirect links might be more complicated than the example behind the link).
Duplicate content - not too difficult to spot:
Examples:
https://www.cheaptubes.com/product-category/industrial-carbon-nanotubes-products/conductive-nanotubes-composite-additive/
https://www.cheaptubes.com/product-category/industrial-grade-carbon-nanotubes/conductive-nanotubes-composite-additive/
seem quite similar to me.
Some pages are also a bit strange - check this url
https://www.cheaptubes.com/product-category/functionalized-carbon-nanotubes/www.cheaptubes.com/product-category/functionalized-carbon-nanotubes/fluorine-functionalized-carbon-nanotubes/ - link is coming from https://www.cheaptubes.com/product-category/functionalized-carbon-nanotubes/ - I guess caused by a wrong formatted relative link.
Try running Screaming Frog to check these issues - it's an incredible tool to help you with issues like this.
Edit: you use canonicals on the strange url's above so they shouldn't really count as duplicates
Dirk