---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 06/15/23: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:00 PM - Ground Block Mounting questions (jcohen@post.com) 2. 12:21 PM - Re: Ground Block Mounting questions (Charlie England) 3. 12:32 PM - Re: Re: Z101 switch state question: engine and main bus shutdown (Charlie England) 4. 12:36 PM - Re: Ground Block Mounting questions (Jeff Luckey) 5. 12:52 PM - Re: Ground Block Mounting questions (Eric Page) ________________________________ Message 1 _____________________________________ Time: 12:00:18 PM PST US Subject: AeroElectric-List: Ground Block Mounting questions From: "jcohen@post.com" I am building an RV7 and have the BandC GB48 48 tab ground block. It appears to have only one pass thru bolt for mounting (pic attached). My questions are: 1. Do people recommend soldering the entire piece ( 0.04 flat brass stock ) to the stainless steel firewall for mounting and good conductivity, in addition to the pass thru bolt provided? If so, just regular solder with flux? And a whopping big iron needed for the heat sink issues? 2. Any reason not to just rivet the brass plate to the firewall? Like dissimilar metal issues between copper and stainless steel? 3. I assume I can flip the bolt direction of the attached picture, to have the pass through bolt head on the interior cockpit side with the tabs, and the protruding stud on the engine side of the firewall, near the battery ground post, so a short ground cable can run from the battery to this ground block stud. But in searching for application pics, I dont see this. I see most people just ground the battery negative post to a nearby firewall bolt hole, Not directly to the ground block. Why not? Package issues? Servicing issues? -------- Jeff Read this topic online here: http://forums.matronics.com/viewtopic.php?p=510975#510975 Attachments: http://forums.matronics.com//files/groundblock_gb48_911.jpeg ________________________________ Message 2 _____________________________________ Time: 12:21:46 PM PST US From: Charlie England Subject: Re: AeroElectric-List: Ground Block Mounting questions On Thu, Jun 15, 2023 at 2:03=AFPM jcohen@post.com w rote: > jcohen@post.com> > > I am building an RV7 and have the BandC GB48 48 tab ground block. It > appears to have only one pass thru bolt for mounting (pic attached). My > questions are: > > 1. Do people recommend soldering the entire piece ( 0.04=9D flat br ass stock > ) to the stainless steel firewall for mounting and good conductivity, in > addition to the pass thru bolt provided? If so, just regular solder with > flux? And a whopping big iron needed for the heat sink issues? > 2. Any reason not to just rivet the brass plate to the firewall? Like > dissimilar metal issues between copper and stainless steel? > 3. I assume I can flip the bolt direction of the attached picture, to hav e > the pass through bolt head on the interior cockpit side with the tabs, a nd > the protruding stud on the engine side of the firewall, near the battery > ground post, so a short ground cable can run from the battery to this > ground block stud. But in searching for application pics, I don=99t see this. > I see most people just ground the battery negative post to a nearby > firewall bolt hole, Not directly to the ground block. Why not? Package > issues? Servicing issues? > > -------- > Jeff > > > I suspect that the tabs would start falling off the plate before you could get it hot enough to solder to something else. Do you have room on the other end to drill for a smaller bolt; say an AN3? I home-brewed my tabs plate, and used a bolt at each end to attach it. The primary bolt is a longer 5/16" from the plumbing isle of the local Ace Aviation supply ( ;-) ) that I ran through the plate, then firewall, nutted, then used as my FWF ground stud, like you're describing. FWIW... ________________________________ Message 3 _____________________________________ Time: 12:32:39 PM PST US From: Charlie England Subject: Re: AeroElectric-List: Re: Z101 switch state question: engine and main bus shutdown On Tue, Jun 13, 2023 at 3:28=AFPM Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > Bob, > For me, the critical factor here is not independent control of the > battery; it's that the aux alternator is effectively playing the role of > the internal generation system of a magneto; supplying electrical energy to > the engine, even when the entirety of the airframe is made electrically > 'cold'. As drawn in Z101: > > > What accessories will be fed from your > proposed aux bus loads that you would > not want to power in combination with > keeping the engine running? > > Electrically induced smoke in cockpit is > an exceedingly tiny risk. So aside from > finding yourself on short-final-to-the-rocks, > when would you expect to want the electrical > system completely 'cold'? This condition > would call for the engine to be shut down > as well. > > Muscle memory? When did this replace a > well conceived and practiced check > list? When faced with a need to reduce > energy consumption in a Z101 architecture, > I would think that line item 1 would be to > switch ENGINE BUS ALTERNATE source feeder ON. > Item 2 would be to switch AUX BUS ALT FEEDER > and AUX ALTERNATOR to ON. 3. Set master switch > to OFF to kill any potential main alternator field > drain and eliminate battery contactor drain. > > snipped > Muscle memory (or no memory at all) tends to replace just about everything if we're stressed. ;-) I don't necessarily disagree with any of the technical points, but most of us are going to revert to decades-old training & practices when we're not absolutely certain what we need to do. And beyond that, I know of a real-world case of someone running an alternative engine to electrical exhaustion when his alternator switch got bumped off. Obviously that should never happen, but moving to an alternative engine after decades of flying mags makes it easier to overlook stuff that wouldn't have mattered with a standard engine configuration. Different strokes, I suppose. Charlie ________________________________ Message 4 _____________________________________ Time: 12:36:33 PM PST US From: Jeff Luckey Subject: Re: AeroElectric-List: Ground Block Mounting questions Hello Jeff, 1. Don't solder it to firewall.=C2- A bolted connection is the correct wa y to attach it (PS, you can't solder stainless) 2. Don't rivet it either.=C2- The typical method is to thru bolt it using 2 big brass bolts.=C2- 5/16 or 3/8 bolts. 3. What you said.=C2- Battery neg directly to one of the big grounding-bl ock mounting-bolts with a big wire.=C2- From that bolt I would also run t he engine grounding strap/cable directly to the block, usually near the sta rter motor. Jeff LuckeyKCMA On Thursday, June 15, 2023 at 12:06:33 PM PDT, jcohen@po st.com wrote: m> I am building an RV7 and have the BandC GB48 48 tab ground block. It appear s to have only one pass thru bolt for mounting (pic attached). My questions are: 1. Do people recommend soldering the entire piece ( 0.04=C3=A2=82=AC=EF =BD flat brass stock ) to the stainless steel firewall for mounting and good conductivity, in addition to the pass thru bolt provided? If so, just regular solder with flux? And a whopping big iron needed for the heat sink issues? 2. Any reason not to just rivet the brass plate to the firewall? Like dissi milar metal issues between copper and stainless steel? 3. I assume I can flip the bolt direction of the attached picture, to have the pass through bolt head on the interior cockpit side with the tabs,=C2 - and the protruding stud on the engine side of the firewall, near the ba ttery ground post, so a short ground cable can run from the battery to this ground block stud. But in searching for application pics, I don=C3=A2 =82=AC=84=A2t see this. I see most people just ground the battery negati ve post to a nearby firewall bolt hole, Not directly to the ground block. W hy not? Package issues? Servicing issues? -------- Jeff Read this topic online here: http://forums.matronics.com/viewtopic.php?p=510975#510975 Attachments: http://forums.matronics.com//files/groundblock_gb48_911.jpeg - S - WIKI - - =C2- =C2- =C2- =C2- =C2- -Matt Dralle, List Admin. ________________________________ Message 5 _____________________________________ Time: 12:52:31 PM PST US Subject: AeroElectric-List: Re: Ground Block Mounting questions From: "Eric Page" My homemade solution is much like what Charlie described, but with one brass bolt in the center. I plan to use a single small bolt elsewhere on the plate just to prevent rotation. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=510979#510979 Attachments: http://forums.matronics.com//files/forest_of_tabs_ground_block_100.jpg ------------------------------------------------------------------------------------- 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.