2/6/10 Meeting Minutes
The meeting began at 7:00PM on February 6th, 2010 at the Peace Lutheran Church in Puyallup.
Chris Holden announced that his hobby shop, Holden's Hobbies, is now carrying a large selection of Estes, Quest, and Madcow rocket kits, including a couple of new kits from Madcow: the PAC-3 and the Prion. Chris also plans to run a booth at the upcoming Model Show in Renton and is looking for people to come display their rockets at his booth. Contact Chris for more details on either his inventory or participating in the model show.
Dave Randall and Brad Wright gave an update on their work as the co-launch directors for FITS.
Dave has been working on plans for two separate contests:
- A Der Red Max drag race. This is aimed mostly at kids, but adults are also welcome to participate.
- A "group build" contest. Each team will receive a bag of parts sufficient to build a rocket and a motor. The team has a limited time to assemble a rocket from these parts and predict the rocket's maximum altitude and flight duration on the given motor. Deductions will be made from each team's score for deviations from their predictions. Teams will have to register beforehand and pay an entrance fee to cover the cost of the parts and motor. Puget Sound Propulsion offered to provide G motors at a discount for the event.
Dave also reports that a "kids program" is being organized. We expect to get more details as work on it progresses.
Dave and Brad have been working with Mike Fisher, of Binder Design, to create a FITS 2010 rocket kit that will be available for purchase before the launch. It will have a 3" airframe, 38mm motor mount, and special decals for FITS 2010. This is so cool! You don't want to miss out on it.
Brad and Dave have been working on creating a better site layout for FITS attendees. Part of this work includes identifying two distinct areas where vendors can locate themselves: west of the main dirt road through camp and on the knoll on the eastern side of camp. The areas have been laid out to give vendors plenty of room. If all vendors decide to occupy the same area, the other will be opened up for more camping.
Dave has been talking to his brother, who has a professional video company, as a possible source for a capable videographer for FITS. His brother is already booked for Memorial Day weekend, so it looks like this probably won't pan out. If you know of anybody that would like to shoot video at FITS for a possible DVD, please let Kent Newman know.
The FITS marketing team (Dave, Brad, and Mike Wyvel) has been looking into offering more FITS clothing options this year, including short and long-sleeved t-shirts and button-ups. Bryan Whitemarsh suggested that FITS hoodies would probably be popular and Brad said he would talk to Mike about it.
Northwest Rocketry Calendar
Kent Newman brought up the idea of producing a high-quality photo calendar of Northwest flyers and their rockets. Rather than being driven by vendors, with each page containing advertisements and coupons, the goal would be to cover the costs of producing the calendar through sales. In order to make this happen, we would need commitments by FITS for a 2011 calendar. The estimated price is $20 - $25. The calendar would be done in concert with NW clubs in our area. While attendees showed interest, it's still unclear whether the project is worth the effort involved.
Kent Newman gave a quick talk on pistons and their correct use. It has been observed that expanding ejection gases can cause a conventional piston to swell, which could contribute to binding and deployment failure. Simply building a piston up-side-down, with the bulk plate at the aft end of the piston's coupler, can prevent this type of swelling and improves reliability. Even with this improved design, proper care of a piston system is critical and Kent emphasized the benefit of using baby powder or a similar dry substance as a piston lubricant.
Western Washington Launch Site Search
Andrew MacMillen presented some of the data he collected a number of years ago while searching for a new launch site in Western Washington, much of which can be found here: http://washingtonaerospace.org/launch_sites/. The goal is to find a launch site west of the Cascades suitable for J - K flights, like we used to enjoy at Monroe. The hope is that we could hold single-day launches once a month that would be more convenient than those in Mansfield. There are a number of good sites already identified. Bill Munds has also been doing some site research in the Mount Vernon area and has identified a site for which only four major landowners would be involved.
The next steps are to gather more information on some of the candidates and determine which landowners need to be approached by the BOD to negotiate access to the land. The BOD will be considering what course of action to take.
Club Safety Program
Jim Wilkerson reminded us of the NAR's "club safety program", where NAR sections can receive a grant of up to $250 to be used to improve club launch safety. We tried this last year, but never heard back from NAR headquarters. We plan to purchase some fire rakes this year and hope to be reimbursed by the program.
Black Powder Talk
Bryan Whitemarsh began this discussion by describing several methods for containing black powder deployment charges in a rocket. He has used PVC "cannons" which are PVC plugs and tubing attached to the ends of an avionics bay. An e-match is inserted, followed by the black powder charge, and, in his case, held in with disposable ear plugs and tape. Bryan also described using pre-built containers, like those available from Newton's 3rd Rocketry built from microcentrifuge tubes and from where Bryan learned the disposable ear plug trick. Others fill the cut-off finger tips of rubber gloves or corners of baggies with BP, insert an e-match, and then seal it up with a quick tie. For higher altitude flights (above about 20,000 feet MSL), the charge can be more reliably lit by placing it inside a section of surgical tubing with an e-match and closing both ends with quick ties.
Brad Wright emphasized the importance of wearing good eye protection whenever working with BP. Many people have seen BP charges go off unexpectedly during preparation. Always use caution and protect yourself, especially your eyes! Brad also recommended having a child's dosage measuring spoon and a small funnel on hand to measure BP and get it into the right place easily and safely. 1 mL (cc) of black powder is equivalent to 1 gram.
Kent Newman then showed us another approach, one that is especially appropriate for really high flights. Kent takes a short section of PVC tubing and hot glues an igniter in one end. Once the glue is dry, he puts the BP in the open end of the tube and then seals it with a generous amount of RTV silicone.
Regardless of how you contain the BP charges in your rocket, it's critical that you ground test your charges to make sure they are properly sized before your rocket's first flight.
Kent Newman gave a good talk on ignitors, including things like how to ensure they work properly and how they are made.
There are a number of things that will make it hard for an igniter to do its job. Old motors can have a layer of oxide on the propellant surface that can inhibit it from igniting. Simply sanding the core of the top grain can be enough to get the motor started. An igniter might not work properly if not placed at the head of the motor; make sure it is inserted all the way to the delay grain. If a motor doesn't have a delay grain, placing a piece of tape across the top of the top grain will stop the igniter from going too far when inserted. Some propellants are just hard to light, for example those containing barium. In these cases, a light coating of pyrogen applied to the core of the top grain can help these motors light and come up to pressure reliably. However, in all cases, don't attempt anything that would void proper motor/safety handling issues.
For those wishing to make their own igniters, pyrogen kits are available from several manufactures. Magnelite from Rocketflite and QuickDip from QuickBurst were mentioned, although there are others. The kits generally come in two parts, which are not regulated. However, when the two are mixed it appears that the resulting compound could be regulated.
An igniter can be created from an e-match by dipping the match in pyrogen and then allowing it to dry. Some e-matches, however, are better suited to this that others. The M-Tek e-match from MJG Technologies can burn too quickly and pop the pyrogen off before it ignites. The MJG J-Tek e-matches, on the other hand, burn slower and are less likely to blow the pyrogen off before igniting it.
Igniters can also be created with conductive pyrogen, which heats up and ignites when current is passed through it. Another approach uses a thin piece of nichrome "bridge" wire between two conductors that is then dipped in pyrogen. When enough current passes through the bridge wire it heats up and ignites the pyrogen.
Tragic Little Aerospace
Robert Geer, Alex Dumas, Dustin Knie, and Nathan Shelby were at the meeting representing Tragic Little Aerospace and showing off their latest electronic rocket gadgets. This stuff has a lot of potential. Contact Robert Geer for more details.
Aaron Evans Alex Dumas Andrew MacMillen Andy Barwick Andy Casillas Bill Munds Bill Wyvel Bob Jimerson Brad Wright Bryan Whitemarsh Carl Hamilton Chuck Tenesch Chris Kamila Chris Holden Dave Randall Dave Woodard Dave Walp David Steckman Dale Woodford Dustin Knie Jim Wilkerson Kent Newman Ian Walp Mike Benight Mikhail Kamila Nathan Shelby Robert Geer Robert Simpson-Clark Ryan Williams Scott Berfield Scott Stabbert