PEKO Precision Products

Large Size Precision Machining Parts - Who's going to make them?

Posted by Scott Baxter on Mar 8, 2016 9:19:00 AM



We all remember the expression "if you build it, they will come".  But the large parts precision fabrication world, it seems to be "If you buy it, they will come".  What I'm referring to is the high demand of large CNC mills, lathes and other machine tools. As we have found out here at PEKO, by providing large parts manufacturing with big mills, customers are able to outsource their parts at an affordable rate.  One problem for these customers is finding machine shops with the work envelopes that meet their need.  Parts with dimensions of 30"+ inches require equipment that most shops don't have.  When looking to outsource typical precision components, most customers have a stable base of local shops that can do the work at a fair price and with quick turnaround.  Due to the scarcity of large machines and people that now how to use them, OEMs are beginning to understand that they may have to employ the services of a new supplier for these difficult jobs.  By doing so correctly, it not only gives them the ability to get their current parts manufactured, but now their designers can design products with large part manufacturability in mind.


When dealing with a new supplier in the large parts category, here are some things you should look out for:

1: Overall work envelope

Different machines are shaped in various orientations.  This is important to note when choosing a precision machining supplier for your parts.  If you have a part that is 45"x 60" x 100", it may not fit on all mills that advertise 100".   The overall envelope matters just as much.  The part may be better suited for a boring mill, horizontal, or gantry mill.  By checking out specs and speaking to the engineers at the supplier's facility, you should be able to understand if your parts can truly fit.

2: Financial Stability

Big parts are usually expensive!  You must ensure that the supplier is financially viable.  Remember, they will be buying large quantities of material, and paying a team of employees over a course of many weeks or months before they ever get paid for all that effort and expenditure.  The last thing you would want is to deal with a company that exhausted all their working capital on WIP and cannot afford to finish the job.  Worse yet, the end up in bankruptcy because they are waiting to get paid (we have seen this many times).  So check the books to make sure your supplier isn't biting off more than they can chew.


3. Process Development Engineers

When dealing with large parts, you are inevitable going to run into unexpected problems.  The right people to deal with these problems are experienced process development or manufacturing engineers.  By having an engineering team in place, the supplier can start to build a repeatable process so that the parts come out correctly every time.  With large and expensive parts, scrapping is a very big deal.  Your parts will probably have difficult features, dimensions and tolerancing that needs to be held.  The engineers will sort out the details regarding fixturing, heat treating, tooling and other attributes that will guarantee success in making the parts.

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For large parts, it's paramount that you look beyond local suppliers to find the experts in this category.  By doing proper homework, and choosing suppliers with the right equipment, financial stability and a capable engineering team, you are on the right track.  Don't be afraid to get a tour of the facility so you can personally inquire about the process and envision your parts in the supplier's shop.  If you have any questions about how PEKO has successfully produced hard to make parts for 50 years, contact me direct at or simply click the button below!

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