-
- News
- Books
Featured Books
- smt007 Magazine
Latest Issues
Current IssueBox Build
One trend is to add box build and final assembly to your product offering. In this issue, we explore the opportunities and risks of adding system assembly to your service portfolio.
IPC APEX EXPO 2024 Pre-show
This month’s issue devotes its pages to a comprehensive preview of the IPC APEX EXPO 2024 event. Whether your role is technical or business, if you're new-to-the-industry or seasoned veteran, you'll find value throughout this program.
Boost Your Sales
Every part of your business can be evaluated as a process, including your sales funnel. Optimizing your selling process requires a coordinated effort between marketing and sales. In this issue, industry experts in marketing and sales offer their best advice on how to boost your sales efforts.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - smt007 Magazine
Ask and Answer - June 5, 2002
December 31, 1969 |Estimated reading time: 3 minutes
Ask and Answer is a forum where SMT professionals with questions can meet up with those with the answers. If you know the answers to any of the questions below, or have questions of your own, please e-mail them to christinef@pennwell.com, referencing the reference number below each question, and we will publish them in a future column. Please include your name and the location you are writing from. SMT Online reserves the right to edit responses. Look for Ask and Answer every Wednesday.
QUESTIONSRuben E. Irizarry-Guzman writes: I am currently experiencing some solder voids. And there are two alternatives to solve it. On the first hand there is a tradition that says that the profile shall be between 3-6 minutes total time. Then there we have the traditional flat profile vs. the ramp profile. Some theories say that with a longer soak zone you reduce voiding but there is also a theory that says that with a continuous ramp profile you do the same. Can you advise? Thank you. Reference Number: 060501
Thomas Kasabula writes: Does anyone know of a software program that takes historical data from Cadence designs, and does a fairly good job at estimating future jobs by the number of holes, size of the board, components, design rules, layers, etc.? I am looking to do estimating or job forecasting. Thank you. Reference Number: 060502
Nunzio Lardizzone of New York state writes: We manufacture audio transducers for the electronics industry. We have been producing only thru hole technology. We are now producing SMT transducers and use nylon 46 for the plastic housing. It seems that nylon 46 does not withstand the high temperatures well. Can you suggest what plastic material we should be using? I would greatly appreciate your help in this matter. Thank you. Reference Number: 060503
Philip Newbury writes: After attending the IPC Lead-Free Conference last week in San Jose, I am interested to hear what your readers feel should be the main initiative(s) for SMT/PTH equipment suppliers, in regard to providing lead-free manufacturing solutions. Thank you. Reference Number: 060504
John Kemp of Canada writes: We are just now making the transition from tried-and-true, ultra-reliable, through-hole double sided to mixed technology CCAs. Our industry is very conservative and demands high reliability and long life (greater than 20 years) products. I have had several "experts" tell me that SMT assemblies will not survive the tests of thermal cycling and of vibration. Several other "experts" say this is not a problem. Is there a good primer on SMT that I can read to get a better understanding of the specific design issues? Thank you. Reference Number: 060505
Randal Kraemer writes: Can someone tell me what the predominant thinking is as to the best approach to masking vias under BGAs when using LPI masks? "Best" should be taken to mean the best process in regard to (in order of priority):
- Long term reliability
- Masking effectiveness
- Assembly yields/ease of assembly (primarily printing of solder paste)
- PWB cost
To minimize your effort for a speedy response, these are what I think the options are: A) Mask over entire pad on comp side only, clearance on opposite side. B) Plug from comp side with epoxy-based mask prior to LPI mask, then LPI over entire pad from both sides. C) Something else. Any input on this subject would be appreciated. Thank you. Reference Number: 060506Angie West writes: I'm looking for someplace to recycle surface mount i.c. tubes and reels. I already deal with Smart Cycle (formally Semicycle) for matrix trays only. They said there wasn't a market for the reels anymore. I also have never found anyone to take i.c. tubes. Most of them are not marked as to what recycle plastic number they are. Let me know where to look. Thank you. Reference Number: 060507Randy Johnson of Alabama writes: I am looking at PC repair equipment and don't know much about SMT, but would like to know what is required/suggested to repair motherboards and the like. Thank you. Reference Number: 060508