---------------------------------------------------------- Rocket-List Digest Archive --- Total Messages Posted Fri 10/14/05: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:30 AM - Re: Prop Extension (blairclan) 2. 06:33 AM - Re: extension (blairclan) 3. 07:19 AM - balancing CHT's (Stewart, Michael (ISS Atlanta)) 4. 07:58 AM - Re: balancing CHT's (Stewart, Michael (ISS Atlanta)) 5. 08:19 AM - Re: Re: Prop extensions (Kevin Shannon) 6. 09:19 AM - Re: balancing CHT's (Tom Martin) 7. 11:02 AM - Re: balancing CHT's (Ernest Hale) ________________________________ Message 1 _____________________________________ Time: 06:30:33 AM PST US From: "blairclan" Subject: RE: Rocket-List: Prop Extension --> Rocket-List message posted by: "blairclan" Yeah, I totally understand your point. I'm only sharing information and what I did because Kevin asked. I'm not really offering any advice as such. For what it's worth, the company that made my extension specializes in extensions. I understand they have 15 years (or was it 25?) making them. It comes with specialized lot traceable bolts etc etc. (After all, extensions are common in light aircraft.) With 90 hours on mine so far I can tell you there are other things that concern me more than that extension. One of the things I'd consider if doing it again, would be to use a smaller extension. It would shorten the nose a bit (which would not be without its own problems) but would remove the "suggested G limit" that most people apply to the M hub. (Another "oh and by the way", Saber told me there is no need for any G restrictions when using this particular extension - but like an M hub I avoid more than 4 G for crank journal load consids.) Good luck Kevin. Cheers, Tony -----Original Message----- From: owner-rocket-list-server@matronics.com [mailto:owner-rocket-list-server@matronics.com] On Behalf Of A1AVIATON@aol.com Subject: Re: Rocket-List: Prop Extension --> Rocket-List message posted by: A1AVIATON@aol.com IT ONLY HAS TO FAIL ONCE, WHAT IS THE HEAT TREAT OF THE METAL, WHAT TYPE OF METAL IS IT, WAS IT TESTED, DO ANY OF THE FACTORY ENGINES USE ONE, YOU ARE A BRAVE MAN, MIKE ________________________________ Message 2 _____________________________________ Time: 06:33:59 AM PST US From: "blairclan" Subject: RE: Rocket-List: extension --> Rocket-List message posted by: "blairclan" Thanks for the suggestion. Done about 90 hours on it now, so it would be a complicated trade/swap. It's all cool, I'm not taking any offence. The list is for bouncing around ideas after all. Cheers Tony -----Original Message----- From: owner-rocket-list-server@matronics.com [mailto:owner-rocket-list-server@matronics.com] On Behalf Of A1AVIATON@aol.com Subject: Re: Rocket-List: extension --> Rocket-List message posted by: A1AVIATON@aol.com IT WILL PROB. WORK OK. I DON'T WANT YOU TO THINK I AM SAYING BAD THINGS ABOUT YOUR PLANE, PERHAPS YOU COULD FIND A' M' HUB. AND HAVE IT SWAPED OVER. CAN YOU IMPORT OR HAVE ONE SHIPPED TO YOUR COUNTRY, I KNOW A PROP SHOP IN FLA. HP PROPELLERS, THEY MAY HAVE ONE. MIKE ________________________________ Message 3 _____________________________________ Time: 07:19:29 AM PST US Subject: Rocket-List: balancing CHT's From: "Stewart, Michael (ISS Atlanta)" --> Rocket-List message posted by: "Stewart, Michael (ISS Atlanta)" I have been trying to get my middle cylinders to warm up and the rears to cool down. #6 is 365 (oil cooler mounted behind it), #4 is 328. I have been trying to stick some 'speed tape' (thick aluminum tape) around the #4 cylinder but I am not making any real progress. Clearly this is a little more complicate to fix than I originally thought. What is the best procedure to prevent cooling of one cylinder to help the others? Rtv between the fins? Top of the cylinder head as opposed to the base? Some other idea? I now have the fuel flow matched to .1gph and now ready to get the temps in line. Help appreciated Thanks Mike S8 Do not archive Flow match details here: http://www2.mstewart.net:8080/super8/nozzles/index.htm ________________________________ Message 4 _____________________________________ Time: 07:58:49 AM PST US Subject: RE: Rocket-List: balancing CHT's From: "Stewart, Michael (ISS Atlanta)" --> Rocket-List message posted by: "Stewart, Michael (ISS Atlanta)" What a bizarre idea. Thanks Archiving _____ From: Bob J [mailto:rocketbob@gmail.com] Subject: Re: Rocket-List: balancing CHT's Mike, take some washers and space the back baffle away from the rear cylinders to expose a 1/8" or so gap between the baffle and the rear cylinders. Two local rocket guys did this and it fixed the hot cylinder problem; Tom Martin up in Canada has also done this and was successful with it. This works on the front cylinders too. We also took a leaf blower and felt around the baffles to find gaps, and sealed up the cooler a little better. We weren't expecting much from that but were surprised to see that the oil temperature dropped 8 degrees. Every little bit can make a difference. Regards, Bob On 10/14/05, Stewart, Michael (ISS Atlanta) wrote: --> Rocket-List message posted by: "Stewart, Michael (ISS Atlanta)" I have been trying to get my middle cylinders to warm up and the rears to cool down. #6 is 365 (oil cooler mounted behind it), #4 is 328. I have been trying to stick some 'speed tape' (thick aluminum tape) around the #4 cylinder but I am not making any real progress. Clearly this is a little more complicate to fix than I originally thought. What is the best procedure to prevent cooling of one cylinder to help the others? Rtv between the fins? Top of the cylinder head as opposed to the base? Some other idea? I now have the fuel flow matched to .1gph and now ready to get the temps in line. Help appreciated Thanks Mike S8 Flow match details here: http://www2.mstewart.net:8080/super8/nozzles/index.htm ________________________________ Message 5 _____________________________________ Time: 08:19:38 AM PST US From: "Kevin Shannon" Subject: RE: Rocket-List: RE: Prop extensions --> Rocket-List message posted by: "Kevin Shannon" I agree Nico, taking a good nap is the most important step in making important decisions. Do not archive Kevin Shannon --> Rocket-List message posted by: "nico css" Take it from me, Kevin, not many things happen at one's 50th. Getting to go to sleep early is good too. :-) > --> Rocket-List message posted by: "Kevin Shannon" > > Yes, I agree these are good points to consider, I am closely examining > all the available options before I make the choice. I have plenty of > time before I actually need the prop in hand. I would have to think that > the short hub and extension version is stronger than a cast extension > "M" hub, if you consider the additional flanged sections. However, I > have not seen a cross section of an "M" hub either, so I could be wrong > about that. > The extra place to leak oil aspect is a definite downer. > Maybe my wife will buy me a branny new Hartzell with the right hub for > my 50th birthday..HA! > > Kevin Shannon ________________________________ Message 6 _____________________________________ Time: 09:19:54 AM PST US From: "Tom Martin" Subject: RE: Rocket-List: balancing CHT's --> Rocket-List message posted by: "Tom Martin" The spacers may work to cool #2 and #5. Also if have a little dam in front of #1 you could try to lower it a bit as well. Check the other cylinders to see if the fins that extend up and down between the spark plugs are clean of casting flashing. There were quite a few cylinders that got shipped with these fins completely blocked. There is only so much air that gets into the baffles. If you can cool the other cylinders this may raise #3 and #4. They have also been my coolest cylinders on my rockets. You could also try to close the gap a bit at the bottom of these cylinders but I have had limited success with this. The problem is that these cylinders get lots of air on the front and back of them. All the other cylinders have baffles pressing against their front or back. Tom Martin -----Original Message----- From: owner-rocket-list-server@matronics.com [mailto:owner-rocket-list-server@matronics.com] On Behalf Of Stewart, Michael (ISS Atlanta) Subject: RE: Rocket-List: balancing CHT's --> Rocket-List message posted by: "Stewart, Michael (ISS Atlanta)" What a bizarre idea. Thanks Archiving _____ From: Bob J [mailto:rocketbob@gmail.com] Subject: Re: Rocket-List: balancing CHT's Mike, take some washers and space the back baffle away from the rear cylinders to expose a 1/8" or so gap between the baffle and the rear cylinders. Two local rocket guys did this and it fixed the hot cylinder problem; Tom Martin up in Canada has also done this and was successful with it. This works on the front cylinders too. We also took a leaf blower and felt around the baffles to find gaps, and sealed up the cooler a little better. We weren't expecting much from that but were surprised to see that the oil temperature dropped 8 degrees. Every little bit can make a difference. Regards, Bob On 10/14/05, Stewart, Michael (ISS Atlanta) wrote: --> Rocket-List message posted by: "Stewart, Michael (ISS Atlanta)" I have been trying to get my middle cylinders to warm up and the rears to cool down. #6 is 365 (oil cooler mounted behind it), #4 is 328. I have been trying to stick some 'speed tape' (thick aluminum tape) around the #4 cylinder but I am not making any real progress. Clearly this is a little more complicate to fix than I originally thought. What is the best procedure to prevent cooling of one cylinder to help the others? Rtv between the fins? Top of the cylinder head as opposed to the base? Some other idea? I now have the fuel flow matched to .1gph and now ready to get the temps in line. Help appreciated Thanks Mike S8 Flow match details here: http://www2.mstewart.net:8080/super8/nozzles/index.htm ________________________________ Message 7 _____________________________________ Time: 11:02:26 AM PST US From: Ernest Hale Subject: Re: Rocket-List: balancing CHT's --> Rocket-List message posted by: Ernest Hale What is the drill if your rear cylinders are running hot? On Oct 14, 2005, at 10:58 AM, Stewart, Michael (ISS Atlanta) wrote: > --> Rocket-List message posted by: "Stewart, Michael (ISS Atlanta)" > > > What a bizarre idea. > > Thanks > > Archiving > > > _____ > > From: Bob J [mailto:rocketbob@gmail.com] > To: Stewart, Michael (ISS Atlanta) > Subject: Re: Rocket-List: balancing CHT's > > > Mike, take some washers and space the back baffle away from the rear > cylinders to expose a 1/8" or so gap between the baffle and the rear > cylinders. Two local rocket guys did this and it fixed the hot > cylinder > problem; Tom Martin up in Canada has also done this and was successful > with it. This works on the front cylinders too. We also took a leaf > blower and felt around the baffles to find gaps, and sealed up the > cooler a little better. We weren't expecting much from that but were > surprised to see that the oil temperature dropped 8 degrees. Every > little bit can make a difference. > > Regards, > Bob > > On 10/14/05, Stewart, Michael (ISS Atlanta) wrote: > > --> Rocket-List message posted by: "Stewart, Michael (ISS Atlanta)" > > > I have been trying to get my middle cylinders to warm up and the rears > to cool down. #6 is 365 (oil cooler mounted behind it), #4 is 328. I > have been trying to stick some 'speed tape' (thick aluminum tape) > around > the #4 cylinder but I am not making any real progress. Clearly this > is a > > little more complicate to fix than I originally thought. What is the > best procedure to prevent cooling of one cylinder to help the others? > Rtv between the fins? Top of the cylinder head as opposed to the base? > Some other idea? I now have the fuel flow matched to .1gph and now > ready > to get the temps in line. > > Help appreciated > > Thanks > > Mike > > S8 > > > Flow match details here: > > http://www2.mstewart.net:8080/super8/nozzles/index.htm > >