---------------------------------------------------------- Zenith601-List Digest Archive --- Total Messages Posted Tue 05/03/11: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:40 AM - Re: Aerodynamic clean-up ideas (douglas.lindsay) 2. 06:03 AM - Re: Re: What a joke (Mark Hubelbank) 3. 06:24 AM - Re: Re: What a joke (Paul Mulwitz) 4. 11:45 AM - Re: Re: What a joke (Afterfxllc@aol.com) ________________________________ Message 1 _____________________________________ Time: 12:40:49 AM PST US Subject: Zenith601-List: Re: Aerodynamic clean-up ideas From: "douglas.lindsay" Thanks everyone! We've now bought the aircraft so going to fly it for a season and then implement as many of these ideas as we can over the winter. Happy flying! Doug Read this topic online here: http://forums.matronics.com/viewtopic.php?p=338721#338721 ________________________________ Message 2 _____________________________________ Time: 06:03:24 AM PST US From: Mark Hubelbank Subject: Re: Zenith601-List: Re: What a joke Is it being suggested that the loctite is not really required? It appears that the original nuts were locking and the replacements are not. Still we use other bolts in critical places which have no locking method like head bolts. I find the idea of using Loctite questionable as I believe it can increase the risk of improper torque applied and if one has to remove it, Loctite claims the temperature to weaken it is 250C, To get anything that hot, parts are much hotter. One would think the bolt strength would be compromised by over heating. According to SAE J429 heat treated bolts should not be subject to temperatures over 260C. I think this means that if a nut ever has to be removed the bolt (and cylinder?) has to be removed. On 05/02/2011 1:20 AM, Thruster87 wrote: > --> Zenith601-List message posted by: "Thruster87" > > A local flight training center that has been using Jabiru aircraft for the past 12yrs, swears by the new nut modification,they found that the new nuts can be torqued more easily [the small nuts feel like they are going to strip the threads during torquing] and since doing the SD have NOT had any more issues.Also they have a wobble bar [10"] which they ground to move about 10 deg and they ground the socket walls so it would fit in.This way NO need to remove any bits from the engine.The jury is still out on the need to use loctite,as without it it would make it a lot easier to re-torque the nuts/studs. Cheers > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=338613#338613 > > -- Mark Hubelbank NorthEast Monitoring 2 Clock Tower Place Suite 555 Maynard, MA, 01754 - USA mhubel@nemon.com 978-443-3955 ________________________________ Message 3 _____________________________________ Time: 06:24:10 AM PST US From: Paul Mulwitz Subject: Re: Zenith601-List: Re: What a joke Hi Mark, I don't know why I am getting into this conversation, but I guess my experience making knives comes into play here. When heat treating steel, the temperature is raised to a desired temperature to reduce brittleness. For tool steels this is usually done to at least 900 or 1000 degrees F. I'm not sure exactly what temperature aircraft bolts are heated to, but I'm quite sure it is well above 250 C. So long as the temperature is kept below the heat treating (tempering) temperature I don't think the characteristics of the steel will be impacted. I also wonder what role LocTite or other friction devices might play here. The large diameter nuts in question should be torqued to a very high and consistent level. I would hope this would keep them from coming loose under expected conditions of vibration and temperature. Lastly, I wonder why amateur builders think they know more about how to keep an engine running properly than the designers of that engine. Paul XL Jab 3300 soon to enter flight test. On 5/3/2011 5:57 AM, Mark Hubelbank wrote: > > Is it being suggested that the loctite is not really required? It > appears that the original nuts were locking and the replacements are > not. Still we use other bolts in critical places which have no locking > method like head bolts. I find the idea of using Loctite questionable > as I believe it can increase the risk of improper torque applied and > if one has to remove it, Loctite claims the temperature to weaken it > is 250C, To get anything that hot, parts are much hotter. One would > think the bolt strength would be compromised by over heating. > According to SAE J429 heat treated bolts should not be subject to > temperatures over 260C. I think this means that if a nut ever has to > be removed the bolt (and cylinder?) has to be removed. > > On 05/02/2011 1:20 AM, Thruster87 wrote: >> --> Zenith601-List message posted by: >> "Thruster87" >> >> A local flight training center that has been using Jabiru aircraft >> for the past 12yrs, swears by the new nut modification,they found >> that the new nuts can be torqued more easily [the small nuts feel >> like they are going to strip the threads during torquing] and since >> doing the SD have NOT had any more issues.Also they have a wobble bar >> [10"] which they ground to move about 10 deg and they ground the >> socket walls so it would fit in.This way NO need to remove any bits >> from the engine.The jury is still out on the need to use loctite,as >> without it it would make it a lot easier to re-torque the nuts/studs. >> Cheers >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=338613#338613 >> >> >> >> >> >> >> >> >> >> >> > ________________________________ Message 4 _____________________________________ Time: 11:45:31 AM PST US From: Afterfxllc@aol.com Subject: Re: Zenith601-List: Re: What a joke Well Paul If you read 4130 it has standards that I and everyone else needs to follow. I have shown this fix to a few A&P's that have said they would NOT sign off if this was on an engine this way. Jabairu has a history of an engine that overheats and distorts cylinders and this is just another example of piss poor engineering. Ask yourself if you would see this on a lycoming or Continental and the answer is no and the reason is because they have to build them to standards where others use experimental as a way to get away with anything. Jeff > Lastly, I wonder why amateur builders think they know more about how to > keep an engine running properly than the designers of that engine. > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith601-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith601-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/zenith601-list Browse Digests http://www.matronics.com/digest/zenith601-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.