![]() ![]() We have and will work with individuals to provide them with opportunities to become and remain compliant with the parking regulations. Our appeal process seeks behavior change as opposed to collecting fines. We prefer higher levels of compliance to the issuing of more citations. ![]() To keep parking fees as low as possible for all users, Transportation Services issues citations to encourage voluntary compliance. To learn more, read this article on ”Why?” on parking citations. However, Transportation Services would prefer to collect drivers’ small daily parking fees instead of issuing citations and collecting a more considerable fine. To that end, the Parking Compliance division of Transportation Services searches for, and issues citations to vehicles parked on campus but are not in compliance with or have not paid the appropriate fee. We also know that many would not pay the smaller parking fee without a significantly higher risk of paying a fine. Hand tapping with form taps is no fun, and I cannot recommend it.UC Davis tasks Transportation Services with funding, managing, and maintaining the campus parking and roadway system entirely by user fees. It is best to get the full depth in one shot, Especially if you don't have a CNC with rigid tapping and your encoder keeps the spindle in lead. Oh, and one last thing about power tapping with a form tap. If you have problems with abrasive materials, and have a rigid enough setup, go ahead with a solid carbide cut tap. If it were me, I believe I would stay with cut taps on nonmetallic materials. The form tap "upsets" the material, and I would think that some, if not most plastics would not respond in such a way to retain the formed thread once the tap is withdrawn. I can speculate that possibly some plastics would not lend themselves to the process. You cannot tap the hole with a standard cut tap if it is drilled for a form tap. So if something happens and you have all your parts drilled, and you run out of form taps, you are stuck getting more. ![]() ![]() The hole drilled is considerably larger than the standard cut tap drilled hole. Since the hole drilled for form taps is larger than for cut taps, the material displaces into the flutes of the tap, thus becoming smaller. Too large and the final minor diameter will be too large, and not in tolerance. Too small and the odds on breaking the tap go up dramatically. If the hole is incorrectly sized you can have problems of two kinds. The tolerance you will need to hold is tighter than for a cut tap. The other, lesser problem is controlling hole size. The acids must reach the entire length of the tap to dissolve it, and all you really have access to is the very top, broken surface. Some of the acid removal methods sort of work, if you can find one that will not attack the aluminum enough to damage the part, but again the lack of flutes makes it mostly impractical. You have a hollow tap, but it will still be stuck. Since there are no flutes, even a sinker EDM burning a hole in it will not leave just pieces stuck in the part threads that nearly fall out on their own. One is when a tap is broken, it pretty much makes scrap of the part. There are two downsides that I will mention. It is smoother, stronger, has no chips to worry about. Overall, the thread produced is superior to a cut tap thread. I cannot speak to the use of form taps in plastic, but I have form tapped literally thousands of holes in both 60 alloys. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |