This is part of our “medical device component questions answered section”. We often have medical device designers ask us questions and we answer them. We recently had a designer ask us how we would approach making a partially PTFE coated hypotube. The part has multiple sections that are coated and multiple sections that are uncoated. See photo above.
There are two ways to do this:
1. Precoated PTFE Wire. You can start out with a fully coated wire and then grind off the ptfe coated wire in certain sections. If you need to grind the wire anyways, this is probably the most affordable approach. This version won’t be as visually appealing since there might be small amounts of PTFE coating left on the wire or the grinding might go slightly into the OD which might create a different service finish.
2. PTFE coating just sections of the wire. In order to achieve this, the coating company will mask sections of the wire which don’t get coated, prior to the coating. This approach will achieve more fluid results, but will be more costly.
If you have wire manufacturing questions don’t hesitate to send them in.