While searching for machine shops — quoted from: https://www.omwcorp.com/how-to-design-machined-parts.html
If you want the best out of your machine shop, it’s important to treat them well. People like to do business with people they like, and it stands to reason that favorite customers get special attention. Here are a few do’s and don’ts regarding machine shop proprieties:
DO communicate regularly with your shop, call them if you perceive a problem. Don’t let problems simmer. Do work with them to resolve issues fairly. Cutting metal to high tolerances is an extremely difficult art, and some mistakes are bound to happen.
DO consult with your shop on design issues. Unless you’ve spent years of your life working as a machinist, don’t assume you know more about manufacturing issues than they do. Virtually all professional machinists have many years of training. Many have advanced degrees. Treat them as peers, not as subordinates.
DO pay your bills on time. Nearly all shops pay close attention to this. There is no question that fast paying customers get treated better.
DON’T use your shop as a free quoting service to scope out the cost of proposed projects. Quotes are expensive for a shop. Only request quotes for jobs the shop has a fair chance to getting. Don’t quote out jobs to more than 2 or 3 shops. Don’t expect a shop to continue to quote multiple jobs without winning some work.
DON’T try to beat a shop down on part costs. Do ask design advice on how part costs can be reduced. Treat your shop as part of your manufacturing team, and foster communication between design and manufacturing.
– PS, to the machine shops we’ve worked with already, thank you!
A clarification. I want to point out that this element is important and it can be challenging to do! If you can’t meet in person, it’s tougher to build repertoire over email or telephone no matter how charismatic you are. And, though I’m usually close to my email, people in shops are on tools and machines most of the time. A phone call is a lot quicker and more personal, but conversations on the phone often lead to miscommunications and frustration. What’s worked for me is talking on the phone, and then summarizing in a follow-up email immediately afterwards. Other points of friction I’ve found are in file formats (I was in Bangalore, India, bouncing between coffee shops and I just couldn’t get the right program in order) and computer use (for instance a shop that insists on 2D drawings of a nice CAD file you struggled to put together…).
Experience says: lavishly praise shops you come across when everything goes smoothly.
Right now: I’m working with an shop called OharaRP (out of Dayton, Ohio) on a PCB board and they kick ass!