---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 05/14/06: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:13 AM - Di-Electric Grease; where used (Wayne Sweet) 2. 08:37 AM - Re: Di-Electric Grease; where used (Richard E. Tasker) 3. 09:03 AM - Re: Di-Electric Grease; where used (Matt Prather) 4. 12:39 PM - Re: Di-Electric Grease; where used (Robert L. Nuckolls, III) 5. 03:10 PM - Re: Canopy Latched Sensor (Joe Dubner) 6. 03:33 PM - Re: Re: Canopy Latched Sensor (Brian Lloyd) 7. 04:31 PM - Glass connectors (Alan K. Adamson) 8. 07:28 PM - RPM sensor wires () 9. 08:16 PM - Re: RPM sensor wires (Bruce Gray) 10. 08:33 PM - Re: Ebay #9723825338 (Robert G. Wright) ________________________________ Message 1 _____________________________________ Time: 07:13:28 AM PST US From: "Wayne Sweet" Subject: AeroElectric-List: Di-Electric Grease; where used --> AeroElectric-List message posted by: "Wayne Sweet" My other toy is a motorcycle, which has electronic everything. Some = riders strongly advocate to apply dielectric grease the connectors for = corrosion protection. But a dielectric is a non-conductor; seem = counter-productive. What am I missing here? Wayne ________________________________ Message 2 _____________________________________ Time: 08:37:25 AM PST US From: "Richard E. Tasker" Subject: Re: AeroElectric-List: Di-Electric Grease; where used --> AeroElectric-List message posted by: "Richard E. Tasker" It has to be a non-conductor or you would short every pin to every other pin. The purpose of the grease is to exclude oxygen and moisture - both of which are needed to degrade the contacts. Dick Tasker Do not archive Wayne Sweet wrote: >--> AeroElectric-List message posted by: "Wayne Sweet" > >My other toy is a motorcycle, which has electronic everything. Some = >riders strongly advocate to apply dielectric grease the connectors for = >corrosion protection. But a dielectric is a non-conductor; seem = >counter-productive. What am I missing here? > -- Please Note: No trees were destroyed in the sending of this message. We do concede, however, that a significant number of electrons may have been temporarily inconvenienced. -- ________________________________ Message 3 _____________________________________ Time: 09:03:29 AM PST US From: Matt Prather Subject: Re: AeroElectric-List: Di-Electric Grease; where used --> AeroElectric-List message posted by: Matt Prather Hi Wayne, Here's my understanding: Properly designed electrical connectors make gas-tight connections between the conductors. This means that as well as squishing all of the air out of the interface, closing the connection will also squish out any other liquid/grease in the joint, including dielectric grease. Applying dielectric grease to a properly designed connector will not interfere with the conductive properties of the joint because the grease will get squished out of the places where the joint is gas-tigth. However, applying dielectric grease may stave off corrosion at the margins of the joint. At the margins (edge) of a connection, there may exist narrow (microscopic) crevices/voids, which can be the perfect environment for corrosion of the materials used to make the connection. Regards, Matt- Wayne Sweet wrote: >--> AeroElectric-List message posted by: "Wayne Sweet" > >My other toy is a motorcycle, which has electronic everything. Some = >riders strongly advocate to apply dielectric grease the connectors for = >corrosion protection. But a dielectric is a non-conductor; seem = >counter-productive. What am I missing here? >Wayne > > > > > > > > > ________________________________ Message 4 _____________________________________ Time: 12:39:55 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Di-Electric Grease; where used --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 07:07 AM 5/14/2006 -0700, you wrote: >--> AeroElectric-List message posted by: "Wayne Sweet" > >My other toy is a motorcycle, which has electronic everything. Some = >riders strongly advocate to apply dielectric grease the connectors for = >corrosion protection. But a dielectric is a non-conductor; seem = >counter-productive. What am I missing here? >Wayne Dow-Corning DC-4 and similar silicone greases are excellent prophylactic treatments for exclusion of moisture and other contaminants into connectors. Waaaayyyy back when, we commonly filled the mating spaces of coax connectors up on towers with DC-4 before putting the connector together. Use sparingly. You don't want it to ooze out and get the exterior all messy. The stuff is VERY hard to get off and in the case of coax connections, made it difficult to wrap with tape for exterior water-barrier. A coating the top insulator and terminal of a spark plug before installing the spark plug wire would be an assist for keeping moisture out of a potentially vulnerable joint in the system. Same thing would be good for coil end of wire. Silicone greases migrate with time. Put a pea-sized dab on a flat surface and come back a few months later. You'll find a large silicone-grease wetted area around the dab that continues to grow with time. It's a neat stuff but I would use it reservedly with respect to amount and location and only in areas where a connection is likely to be exposed to extra-ordinarily corrosive influences. Bob . . . --------------------------------------------------------- < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss > --------------------------------------------------------- ________________________________ Message 5 _____________________________________ Time: 03:10:34 PM PST US From: Joe Dubner Subject: AeroElectric-List: Re: Canopy Latched Sensor --> AeroElectric-List message posted by: Joe Dubner > I'm not familiar with any specific reflective-type optical sensors > but I'm guessing that would be the way to go. Following up on my original post here ... After a couple of weeks of scratching my head, I found the IR HOA0149 Reflective Sensor ($3.36 ea. at DigiKey, see http://rocky.digikey.com/WebLib/Honeywell%20Sensing%20%26%20Control/Web%20Data/HOA0149.pdf). I breadboarded a circuit and found that it worked pretty well as long as: 1) The LED was heavily biased (30 or 40 ma. but not 10 or 20). 2) The reflective object was a flat surface (unlike the domed head of the screw I wanted to use). Even the Phillips slots in the head diffused the reflective light considerably and reduced the sensitivity. 3) The reflective object was fairly close to the optimum position as specified in the data sheet. There wasn't a lot of in/out, left/right, or up/down tolerance on positioning the latch handle relative to the Reflective Sensor. In order to turn ON a warning light when the latch handle was out of position (not latched) an inverter was required so I added a resistor and transistor. The Reflective Sensor has a poor current transfer ratio and there is less than one milliampere available to bias the transistor, sometimes much less depending on position. In order to reliably control the #382 light bulb in my Canopy Unlatched indicator I decided I needed a Darlington-connected configuration. This is where I pulled the plug. I decided it was too complicated and "touchy" for my real-world application and I'd rather be flying. Soooooo, I went back to a Cherry microswitch . Maybe I'll look at this again in my *next* airplane when I have more freedom in the mechanical design. -- Joe Joe Dubner Long-EZ 821RP Lewiston, ID On 27-Apr-06 09:21 Joe Dubner wrote: > I'm looking for a better way to implement the canopy unlatched warning > system on a Long-EZ. The standard method is to use a small microswitch > that responds to "canopy latched". (This is not the same as "canopy > closed", which would be easy enough to implement but I want a "latched" > indication.) > > Here's an illustration of the standard system: > http://users.lewiston.com/hth/jd/CanopyLockMicroswitch.jpg > > When the canopy locking handle is pushed forward (left in the image) far > enough to latch the canopy locking mechanism, the head of the screw on > the handle (at the right in the image) fits in the hole on the latch and > actives the microswitch through its (specially bent) lever. > > I'm not happy with the microswitch as it doesn't hold up well under use > and wonder if any Aeroelectric Connection readers can come up with a > better idea. I've searched for optical interrupters but can't find one > with a gap large enough for the head of the relatively large #10 screw. > I'm not familiar with any specific reflective-type optical sensors but > I'm guessing that would be the way to go. > > Any ideas? > > Thanks, > Joe > Long-EZ 821RP > Lewiston, ID ________________________________ Message 6 _____________________________________ Time: 03:33:37 PM PST US From: Brian Lloyd Subject: Re: AeroElectric-List: Re: Canopy Latched Sensor --> AeroElectric-List message posted by: Brian Lloyd On May 14, 2006, at 3:00 PM, Joe Dubner wrote: > > This is where I pulled the plug. I decided it was too complicated and > "touchy" for my real-world application and I'd rather be flying. > Soooooo, I went back to a Cherry microswitch . Maybe I'll look > at this again in my *next* airplane when I have more freedom in the > mechanical design. Sometimes a checklist item is the best solution. Brian Lloyd 361 Catterline Way brian-yak AT lloyd DOT com Folsom, CA 95630 +1.916.367.2131 (voice) +1.270.912.0788 (fax) I fly because it releases my mind from the tyranny of petty things . . . Antoine de Saint-Exupry ________________________________ Message 7 _____________________________________ Time: 04:31:06 PM PST US From: "Alan K. Adamson" Subject: AeroElectric-List: Glass connectors --> AeroElectric-List message posted by: "Alan K. Adamson" http://www.l-com.com/home.aspx Various items like DIN connectors for keyboards (both front and rear panel mount), USB connectors, extensions, etc. Plus lots of others. Add to your bookmarks, Alan ________________________________ Message 8 _____________________________________ Time: 07:28:16 PM PST US From: Subject: AeroElectric-List: RPM sensor wires --> AeroElectric-List message posted by: Hello, I am installing an RPM sensor that screws into one of the vent ports on my Bendix Magneto unit. Does the RPM sensor wires have to be shielded all the way to the engine analyzer? If so, I will be installing a 17 pin circular connector at the firewall that will connect all the wires for the various engine sensors (ie. oil temp, oil press, fuel flow..) including the RPM sensor. Do you lose the shielding effect if you run the shielded RPM wires through a circular connector? Thank you Vic ________________________________ Message 9 _____________________________________ Time: 08:16:46 PM PST US From: "Bruce Gray" Subject: RE: AeroElectric-List: RPM sensor wires --> AeroElectric-List message posted by: "Bruce Gray" You have to carry the shield through the connector on it's own pin. Bruce www.glasair.org -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of vicster@netvigator.com Sent: Sunday, May 14, 2006 7:59 PM Subject: AeroElectric-List: RPM sensor wires --> AeroElectric-List message posted by: Hello, I am installing an RPM sensor that screws into one of the vent ports on my Bendix Magneto unit. Does the RPM sensor wires have to be shielded all the way to the engine analyzer? If so, I will be installing a 17 pin circular connector at the firewall that will connect all the wires for the various engine sensors (ie. oil temp, oil press, fuel flow..) including the RPM sensor. Do you lose the shielding effect if you run the shielded RPM wires through a circular connector? Thank you Vic ________________________________ Message 10 ____________________________________ Time: 08:33:05 PM PST US From: "Robert G. Wright" Subject: RE: AeroElectric-List: Ebay #9723825338 --> AeroElectric-List message posted by: "Robert G. Wright" I just ordered one of these from Gilchrist. Since all of their summer help has left college already, they're having a hard time keeping up with returning calls. It took them 3-4 days to get back with me, even after I left them emails and voicemails. So you'll have to be patient, but Marian (sp?) did call me and we finished up. This was just on Friday so it'll be a few days before it gets delivered from MT to AL. I did, however, get all of my payment and package shipped notices by COB Friday, complete with tracking numbers. Rob Wright RV-10 #392 -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Saturday, May 13, 2006 2:49 PM Subject: Re: AeroElectric-List: Ebay #9723825338 --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 12:53 PM 5/13/2006 -0500, you wrote: >--> AeroElectric-List message posted by: "Jerry Grimmonpre" > >Bob ... >Is this Gilchrist coax stripper suitable for RG-400? It has three blades >but does not list RG-400. Gilchrist will not respond to questions. >Thanks ... >Jerry Grimmonpre' Yes, that's the one I give away at the seminars. It's ADJUSTABLE. It will probably work for RG-400 as received but you can check the results of the cuts carefully and adjust as needed for optimization. Bob . . .