Good morning Ladies and Gentlemen!
We ran into a surprising issue the last few weeks. It was stressing me out to no end. For those who don't know, we do this full time and usually run thousands of parts per week. This will be an involved post, mostly directed at the other pros on this page. But, keep in mind there is a lot to be learned for even beginners about trouble shooting and problem solving.
A little background up front:
- We have a dip arm that can be adjusted for speed precisely.
- Film came directly from Mossy Oak, 60 meter roll just a couple weeks old. Stored in my climate controlled office.
- I build fixtures that are adjustable for angle, which we set consistently with an angle gauge
- All parts are firmly connected at exactly the same angle. I use a tool lathe to ensure proper sizing and true surfaces for part mounting.
- Activator is applied with an automated spray system.
- Ultimately, we take out much of the human aspect and can dial in our settings very precisely in small increments.
These parts are duck calls for a large OEM. We tested these last year for them, and all the testing on identical fixtures worked beautifully. We have 3010 of these to dip, and with our tooling would run 288 per run at about 1.5 runs per day, averaging 432 calls per day. Should have been a couple week job max.
We get in the first run, fab up the part holders, and start going with the settings we tested previously. We kept getting these results:
Keep in mind, this seemed up perfect at these exact settings. At best, we were at about 25% reject rate on the calls. Not acceptable for production. I don't need a perfect dip, just one that can be touched up. We adjusted one thing at a time for nearly 3 weeks. Angle, activation, dip speed, soak time, etc. At this point, we started running late on the expected deadlines, and more calls were arriving. Like over 3000 more calls of the next model. Multiple **badwords** were leaving my mouth those weeks. I DO NOT like missing deadlines. But quality always comes first. Finally, my shop supervisor Wes decided to try some Shadow Grass Blades we had from last year's run of calls. It worked PERFECTLY. Hmm... So next we tested some of the New Bottomland film from Big Brain that had been in my climate controlled office since we tested the calls about 8-10 months ago. It also worked perfectly... twice. We again confirmed by placing two fixtures at the exact settings angles with two pieces of film (one from each supplier) on the tank simultaneously. Exact same settings, one was 100% success with beautiful seams, the other looked like the photo above. Here is what I consider a good dip. Still some voids, but can be touched up quickly.
So... I contacted Mossy Oak and also ordered more film from Big Brain. The Big Brain film worked flawlessly, and the new mossy oak film did as well. Hats off to Mossy Oak/3D Fluid Graphics for standing behind their product and to Tony Stubbs for sending new film to test ASAP after our phone conversation. Great customer service.
Ultimately, we got the new film, and have nearly a 0% reject rate. It's VERY rare that the film is to blame. And even more rare that we can't get it to work acceptably. I always assume it's me or my guys screwing up until I can eliminate every possibility. Especially since there are no guarantees that one film acts like any other. In this case, maybe we got a remnant leftover roll that had been sitting for some time. Had the parts been another simple shape other than cylinders requiring a good wrap, it may have worked just fine.