---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 08/15/10: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:49 AM - Firewall Hot-Side Enclosure (Scott Klemptner) 2. 08:19 AM - Re: Firewall Hot-Side Enclosure (Jared Yates) 3. 10:11 AM - Re: Firewall Hot-Side Enclosure (Robert L. Nuckolls, III) 4. 10:47 AM - Re: Firewall Hot-Side Enclosure (Robert L. Nuckolls, III) 5. 03:45 PM - headset cushions (bob noffs) 6. 03:59 PM - Re: headset cushions (Richard Dudley) 7. 06:55 PM - Re: headset cushions (F. Tim Yoder) 8. 06:57 PM - Re: headset cushions (DeWitt (Dee) Whittington) 9. 07:27 PM - Re: headset cushions (Ken) ________________________________ Message 1 _____________________________________ Time: 07:49:34 AM PST US From: Scott Klemptner Subject: AeroElectric-List: Firewall Hot-Side Enclosure speaking from experience, the Lamar "box" as found in current production Cessna's is a royal PITA for maintenance.... job...replace starter relay 2000 cessna 172 (for the second time!) remove ground wire from battery remove several buss bars (mounting bolts obstructed) remove master relay (mounting bolts obstructed) remove avionics relay(mounting bolts obstructed) remove ground power relay(mounting bolts obstructed) remove and replace starter relay(mounting bolts obstructed) replace ground power relay (remember those @#%& obstructed mounting bolts?) replace avionics relay (remember those @#%& obstructed mounting bolts?) replace master relay (remember those @#%& obstructed mounting bolts?) replace buss bars (remember those @#%& obstructed mounting bolts?) replace ground wire to battery TIME INVOLVED over 2 hours ===================================== job...replace starter relay 1971 cessna 150 remove ground wire at battery (optional IMO as there are NO hot wires near the starter relay) remove and replace starter relay replace ground wire at battery (optional IMO as there are NO hot wires near the starter relay) TIME INVOLVED 10 minutes (15 if ground wire removed) Scott A Klemptner bmwr606 on Yahoo IM The difference between genius and stupidity is that genius has its limits- Anonymous ________________________________ F Time: 10:33:00 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Firewall Hot-Side Enclosure At 04:09 PM 8/13/2010, you wrote: >I was thinking about how it might be convenient to house some of the >electrical components on the hot side of the firewall inside of an >environmentally sealed plastic box. Most land vehicles use >something similar, and if I remember correctly Cessna started doing >something similar on their post-1997 production singles. The items >that I had in mind were the contactors, current limiters, shunts, >maybe a small fuse block for the battery bus, and that sort of >thing. The box would keep out the engine compartment grime, and >there are lots of different designs available in the sporting goods >industry. Has anyone done something similar, or can anyone think of >why this would be a bad idea? The strongest motivation for doing such things in production had to do with modularizing certain tasks which were ultimately farmed out to other firms. Lamar and Kelly were both examples of firms offering assemblies of many parts that were installed as a simpler, single operation on the production line. While elegant in terms of labor to install, it was less than elegant in terms of weight, cooling, being able to optimally position contained components and hassles of working inside a more constrained space for maintenance. Nonetheless, it's something of a "fad" . . . There's a big power distribution box in the tail of a Premier that's easy to install, easy to take out and set on the bench . . . but in the airplane it's impossible to troubleshoot and out of the airplane you can't operate it for the purposes of troubleshooting. Production line convenience was traded for weight and constraints on field maintenance. What ever rings your bells . . . Bob . . . _ ________________________________ Message 2 _____________________________________ Time: 08:19:17 AM PST US Subject: Re: AeroElectric-List: Firewall Hot-Side Enclosure From: Jared Yates Good points, thanks for the info. With your advice and Bob's, I'll save the t rouble and find something else to spend time on. On a related note, would th e "liquid electrical tape" stuff be suitable for insulating some of those ex posed hot conductors? On Aug 15, 2010, at 10:47, Scott Klemptner wrote: > speaking from experience, > the Lamar "box" as found in current production Cessna's is a royal PITA f or maintenance.... > > job...replace starter relay 2000 cessna 172 (for the second time!) > remove ground wire from battery > remove several buss bars (mounting bolts obstructed) > remove master relay (mounting bolts obstructed) > remove avionics relay (mounting bolts obstructed) > remove ground power relay (mounting bolts obstructed) > remove and replace starter relay (mounting bolts obstructed) > replace ground power relay (remember those @#%& obstructed mounting bolts? ) > replace avionics relay (remember those @#%& obstructed mounting bolts?) > replace master relay (remember those @#%& obstructed mounting bolts?) > replace buss bars (remember those @#%& obstructed mounting bolts?) > replace ground wire to battery > > TIME INVOLVED over 2 hours > > ========================= ============ > job...replace starter relay 1971 cessna 150 > > remove ground wire at battery (optional IMO as there are NO hot wires near the starter relay) > remove and replace starter relay > replace ground wire at battery (optional IMO as there are NO hot wires nea r the starter relay) > > TIME INVOLVED 10 minutes (15 if ground wire removed) > > Scott A Klemptner > bmwr606 on Yahoo IM > > The difference between genius and stupidity is that genius has its limits- Anonymous > > > > > > F > > > Time: 10:33:00 AM PST US > From: "Robert L. Nuckolls, III" > Subject: Re: AeroElectric-List: Firewall Hot-Side Enclosure > > > At 04:09 PM 8/13/2010, you wrote: > >I was thinking about how it might be convenient to house some of the > >electrical components on the hot side of the firewall inside of an > >environmentally sealed plastic box. Most land vehicles use > >something similar, and if I remember correctly Cessna started doing > >something similar on their post-1997 production singles. The items > >that I had in mind were the contactors, current limiters, shunts, > >maybe a small fuse block for the battery bus, and that sort of > >thing. The box would keep out the engine compartment grime, and > >there are lots of different designs available in the sporting goods > >industry. Has anyone done something similar, or can anyone think of > >why this would be a bad idea? > > The strongest motivation for doing such > things in production had to do with modularizing > certain tasks which were ultimately farmed out > to other firms. Lamar and Kelly were both > examples of firms offering assemblies of > many parts that were installed as a simpler, > single operation on the production line. > > While elegant in terms of labor to install, > it was less than elegant in terms of weight, > cooling, being able to optimally position > contained components and hassles of working > inside a more constrained space for maintenance. > > Nonetheless, it's something of a "fad" . . . > There's a big power distribution box in > the tail of a Premier that's easy to install, > easy to take out and set on the bench . . . > but in the airplane it's impossible to > troubleshoot and out of the airplane you > can't operate it for the purposes of > troubleshooting. > > Production line convenience was traded for > weight and constraints on field maintenance. > > What ever rings your bells . . . > > > Bob . . . > > > > > > _ > > > > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 3 _____________________________________ Time: 10:11:22 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Firewall Hot-Side Enclosure At 10:18 AM 8/15/2010, you wrote: >Good points, thanks for the info. With your advice and Bob's, I'll >save the trouble and find something else to spend time on. On a >related note, would the "liquid electrical tape" stuff be suitable >for insulating some of those exposed hot conductors? To what purpose? There are thousands of instances on multi-millions of vehicles where there are "exposed hazards". Fans, fan belts, whirling propellers, sucking engine intakes, pinch points, non-insulated electrical connections, etc. etc. http://aeroelectric.com/Pictures/Breakers/Breaker_Panel_Busing_2.jpg The firewall of an A36 Bonanza is covered with exposed, high current electrical connections. The questions to be asked and answered are, what conditions are necessary to make risks for these potential hazards to rise to significance. For example, taxiing up to the pumps on a little airport with no human being in sight is a significantly lower risk for getting your propeller messy than at an airshow with little kids running around with abandon. Take each instance of concern. Are there others like it on other airplanes? Particularly airplanes with long production histories? Imagine the task of approaching this configuration with crowbar and hammer in hand with a task, "go forth my son and cause some part of the airplane to contact this exposed terminal." With some reasonably attentive study and application of common sense, I think you'll find that the risks are so low as to not be worthy of concern . . . for there are OTHER risks to flight that are worthy of much concern. Finally, "liquid tape" is probably not a material worthy of critical application anywhere. It's nothing more robust than some coating of plastic paint that one might brush over any surface. It's been my experience that the more you try to "cover things up" for what ever reason, the more likely you are to trap moisture underneath imperfect coatings and set up conditions for corrosion to progress un-observed. Bob . . . ________________________________ Message 4 _____________________________________ Time: 10:47:33 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Firewall Hot-Side Enclosure At 09:47 AM 8/15/2010, you wrote: >speaking from experience, >the Lamar "box" as found in current production Cessna's is a royal >PITA for maintenance.... > >job...replace starter relay 2000 cessna 172 (for the second time!) >remove ground wire from battery >remove several buss bars (mounting bolts obstructed) >remove master relay (mounting bolts obstructed) >remove avionics relay (mounting bolts obstructed) >remove ground power relay (mounting bolts obstructed) >remove and replace starter relay (mounting bolts obstructed) >replace ground power relay (remember those @#%& obstructed mounting bolts?) >replace avionics relay (remember those @#%& obstructed mounting bolts?) >replace master relay (remember those @#%& obstructed mounting bolts?) >replace buss bars (remember those @#%& obstructed mounting bolts?) >replace ground wire to battery > >TIME INVOLVED over 2 hours Yup, your first hand experience conforms with my first-hand impressions for having seen one such assembly for the first time. I'll suggest that such inventions are the product of folks who have never turned a wrench yet are charged with "modularizing" portions of the airplane for "manufacturing convenience". This trend gives rise to the notion that if you modularized 99% of the airplane's components and systems, those modules can be farmed out. Then all we have to do is bring in truck-loads of tinker-toys, put tab-A-into-slot-B and presto- changeo, you have an airplane. That concept bit Boeing in the hind end big time on the 787. But it's amazing to watch the same experiment being tried over and over again by individuals who are surprised with the results. I'm not suggesting that modularizing is always bad. Certainly engines, radios, instruments, etc have been proven by many repeatable experiments to lend themselves well to outside production. But there are limits beyond which the return on investment becomes exceedingly poor. Bob . . . ________________________________ Message 5 _____________________________________ Time: 03:45:33 PM PST US Subject: AeroElectric-List: headset cushions From: bob noffs hi all, i have a lightspeed headset that has become separated from the cloth covered ear cushions. cushions and headset are fine but some adhesive to reconnect. anyone have a solution ? bob noffs ________________________________ Message 6 _____________________________________ Time: 03:59:36 PM PST US From: "Richard Dudley" Subject: Re: AeroElectric-List: headset cushions Hi Bob, I've owned two Lightspeed headsets. On several occasions, there were problems with the cushions. I contacted the manufacturer, and they sent me new ones free of charge. On another occasion, the sheathing of the wires to or from the battery box had slipped uncovering the insulation of the wires. This time they said send them the headset and they would repair free of charge. I would suggest that you discuss your problem them with. If their policy has not changed, i expect that they will repair or replace parts without charge. Regards, Rich Dudley ----- Original Message ----- From: bob noffs To: aeroelectric list Sent: Sunday, August 15, 2010 6:43 PM Subject: AeroElectric-List: headset cushions hi all, i have a lightspeed headset that has become separated from the cloth covered ear cushions. cushions and headset are fine but some adhesive to reconnect. anyone have a solution ? bob noffs ________________________________ Message 7 _____________________________________ Time: 06:55:00 PM PST US From: "F. Tim Yoder" Subject: Re: AeroElectric-List: headset cushions If you send it back to them they will probably fix it for free and maybe give you some upgrades, depending on the model. ----- Original Message ----- From: bob noffs To: aeroelectric list Sent: Sunday, August 15, 2010 3:43 PM Subject: AeroElectric-List: headset cushions hi all, i have a lightspeed headset that has become separated from the cloth covered ear cushions. cushions and headset are fine but some adhesive to reconnect. anyone have a solution ? bob noffs ------------------------------------------------------------------------- ----- Checked by AVG - www.avg.com 08/14/10 23:35:00 ________________________________ Message 8 _____________________________________ Time: 06:57:06 PM PST US Subject: Re: AeroElectric-List: headset cushions From: "DeWitt (Dee) Whittington" Yes, Rchard, I've twice sent my old Lightspeeds back to the company and twice I got refurbished, new looking headsets back...free. Great folks. Dew On Sunday, August 15, 2010, Richard Dudley wrote: > > > Hi Bob, > > I'veowned two Lightspeed headsets. On several occasions, > there were problems with the cushions. I contacted the manufacturer, and they > sent me new ones free of charge. On another occasion, thesheathing of the > wires to or from the battery box had slipped uncovering the insulation of the > wires.This timethey said send them the headset and they would repair > free of charge. I would suggest that youdiscuss your problemthem > with. If their policy has not changed, i expect that they will repair or replace > parts without charge. > > Regards, > > Rich Dudley > > ----- Original Message ----- > From: > bob noffs > To: aeroelectric list > Sent: Sunday, August 15, 2010 6:43 > PM > Subject: AeroElectric-List: headset > cushions > > > hi all, i have a lightspeed headset that has become separated from the > cloth covered ear cushions. cushions and headset are fine but some adhesive to > reconnect. > anyone have a solution ? > bob noffs > > href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.matronics.com/Navigator?AeroElectric-List > href="http://forums.matronics.com">http://forums.matronics.com > href="http://www.matronics.com/contribution">http://www.matronics.com/c > > -- DeWitt (Dee) Whittington www.VirginiaFlyIn.org Building Glasair Sportsman with partners ________________________________ Message 9 _____________________________________ Time: 07:27:53 PM PST US From: Ken Subject: Re: AeroElectric-List: headset cushions Contact cement works fine. Better than the original glue. Ken bob noffs wrote: > hi all, i have a lightspeed headset that has become separated from the > cloth covered ear cushions. cushions and headset are fine but some > adhesive to reconnect. > anyone have a solution ? > bob noffs > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.