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RE: Could it be that Flying Models server is just down?
Both sites seem to be back up now.
Posted on: 10/14/2009 9:33 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9172284
RE: Norvel .074 - when is tight too tight?
I've been kicking around what DD said above about clearances being in the .0001 to 0.0002 range. Though I admit I don't have any real information to dispute it, it just doesn't sit right in my head. Clearances in the thousandths are pretty common, but ten thousandths? My little bit of machining experience says these kind of tolerances are pretty tough to get. Are the fits really that tight?
Posted on: 10/12/2009 3:31 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9167072
RE: Norvel .074 - when is tight too tight?
[quote]ORIGINAL: combatpigg You could wear the piston in naturally if you had enough liner shims and enough patience, removing shims as the piston settles in. [/quote] [:D] I think you just hit the nail on the head, my desire for instant results versus the craftmanship approach.
Posted on: 10/10/2009 11:27 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9161558
RE: Norvel .074 - when is tight too tight?
I haven't tried raising the liner. It get's really tight maybe 15 to 20 degrees before TDC, so I'm not sure raising the liner a bit will help, but I'll give it a try.
Posted on: 10/10/2009 9:59 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9161411
RE: Norvel .074 - when is tight too tight?
Well, I had to abort the attempt to start it, it's still just too tight to get running. I think I'm going to have to try and lap it a bit. I have a weird metric micrometer that is marked in 1/20 millimeters on the fine scale. It works ok for most things, but just not right for checking clearances that run in the thousandths. Going to go get a nice new caliper set with digital readout tomorrow. What do you guys think optimum clearance is from cylinder to piston? I might as well have a target to aim for.
Posted on: 10/9/2009 10:22 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9160680
RE: Norvel .074 - when is tight too tight?
I hadn't really thought about the benefit on compression in terms of bringing the piston down after TDC. I was thinking in terms of the added load on the approach to TDC. I also have some late version LM pistons and cylinders. I mic'd all the pistons I had and for the two that I knew were LM, there was a definite difference between the stock aero pistons and the LM pistons. The setup I'm currently running is a LM liner with a stock piston. ID measurements with my standard type micrometer is not 100% accurate, but from checking a couple of the liners, the LM liner and the stock liner seem pretty close.
Posted on: 10/9/2009 5:49 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9159984
RE: Norvel turbo heads
I'm on the list for a turbo head if you do make some.
Posted on: 10/9/2009 10:08 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9158908
RE: Norvel .074 - when is tight too tight?
Well after swapping rods and getting the engine all cleaned up, I guess I made some progress before killing the first rod after all. Cleaned out and oiled up, I can now get the piston through TDC with a strong turn by hand. I'm getting significant pinch at about 40 to 45 degrees from TDC, but with a good grip on the prop and keeping the motion going, I can get it through TDC without feeling like the engien was goign to twist out of my hand. So at this point it only feels like a very very tight brand new Norvel. I didn't have much time to work on it today, so tomorrow I should be able to hand flip it a few hundred times and see if I can loosen it up to only extremely tight from astronomically tight. I may also put the head back on it. Up until this point, it's been soo tight, I've been reluctant to add compression to that load.
Posted on: 10/8/2009 9:04 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9157705
RE: Norvel turbo heads
I sent an email through E*bay to asking about an .074 turbo head about 3 weeks ago and got no reply.
Posted on: 10/8/2009 6:53 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9157385
RE: Norvel .074 - when is tight too tight?
Well, I finally got a chance to get out and fool with the 074 again. I guess I actually answered my own question in a way about how tight is too tight. I can safely say that it's too tight when you bend a precious rod. I had oiled it up well, gave it a preheat and was spinning it over with the 1/2a starter with the plug out when I noticed it seemed to have a sort of jump. Took the backplate off and lo and behold I bent the hell out of the rod. As I don't have a huge supply of rods to keep bending, I think I need to rethink my strategy. What are my other options for getting this loosened up?
Posted on: 10/7/2009 9:14 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9155104
RE: .15 SWR !!
CP, Why not build the wing as a single span rather than in halves? I guess where I'm headed is whether having a continuous spar reduces the amount of reinforcement needed in the center section? Duke
Posted on: 10/3/2009 5:52 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9144079
RE: Norvel .074 - when is tight too tight?
CP, I think I'll run it in a bit more with the 1/2a starter and heat gun. Get it warm and give it a good spin with the small starter. Rog, that's a good point about shims, I'll dig some more out of the box of goodies. I think I'll have a winner at the end of the day, just got to baby it along first.
Posted on: 10/2/2009 10:49 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9142485
Norvel .074 - when is tight too tight?
So after losing a piston cylinder set to stupidity on my part due to a lean run after forgetting to reset needle, I changed the P/L and found the next set not quite up to my expectations for fit. So I started mix and matching through the pistons and cylinders I have and found a set with what seemed like an exceptionally good fit. It was initially so tight I couldn't turn it through by hand using a reasonable amount of force. I've done the oil soak to season the cylinder, used the heat gun and gave it about 100 flips and it's still tight as hell. I heated it again and with a shot of heavy oil on the piston gave it a short blip with the 1/2a starter (maybe 200 revs or so). Still pretty much locks up completely at TDC even after that. So what to do next? Go ahead and move on to running break in or do I try and get the fit a bit better before trying to run it? This has the potential to be a good set, but I don't want to ruin it inadvertantly. Advice? Duke
Posted on: 10/1/2009 10:45 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9140171
RE: Low wing DNU!
I approve. No good DNU thread should ever die.
Posted on: 10/1/2009 10:20 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9140086
RE: Speaking of changes - fuel
On Tower's site they say the sidewinder pro is 30% nitro and 10% castor? Someone else said it was synth/castor blend. Anybody know for sure?
Posted on: 9/22/2009 11:32 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9115112
RE: 1/2 Pylon Video
I'm just going to go by Academy and get some leader. I ordered Keith Sparks "Building with foam" book and really want to try a few ideas, but a good cutting setup is action item 1.
Posted on: 9/19/2009 3:23 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9108011
RE: Ruined my weekend
If it's not too late, try and cut along the panel lines as much as you can. Then you can put down a thin strip of black where the cut is and when you lay the covering back down any small gap will be less noticeable. I wouldn't CA the covering back down, just use your heat gun to warm it when you pull it up, then maybe balsa rite or stixit type product to put it back down. Duke
Posted on: 9/19/2009 3:21 PM by Author "Dukester"
in the forum "Beginners"
http://www.rcuniverse.com/forum/fb.asp?m=9108009
RE: 1/2 Pylon Video
I'm using a home built AC source. The nichrome wire I have gets hotter in the middle than the ends and if I turn the power up enough to get the ends hot enough then I get soo much stretch I end up parting the wire trying to keep it fairly tight. Duke
Posted on: 9/19/2009 11:56 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9107694
RE: 1/2 Pylon Video
Thanks, I've been playing around with my basic cutting bow and tried guitar string and nichrome without really loving either. nichrome seems to heat unevenly and the guitar string just seems to skip or drag in the foam.
Posted on: 9/18/2009 9:43 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9106679
RE: 1/2 Pylon Video
[quote]ORIGINAL: jfinch They're all more or less custom. I've cut wing cores for some people and Marty sells more or less complete kits that some are flying. But still by and large they are each custom built. ps there is a slapped together video of my build process on my vimeo site. You can find it by going to the link in the first post in this thread then scrolling down through my videos located on the upper right hand side of the screen. I'd link directly to it but I'm on my phone and its too hard to do. [/quote] What kind of wire do you use on your foam cutter?
Posted on: 9/18/2009 2:58 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9105901
RE: 1/2 Pylon Video
Are the planes pretty custom are do most of the guys build from a base plan?
Posted on: 9/17/2009 2:24 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9103400
RE: Cox 333 and 334 spring starters
Are you asking what a spring starter is for or what exact engine those two models fit? The basic answer is you use it to wind the prop clockwise (from the front) to tighten the spring and then when you let it go it'll spin the prop through the compression cycle maybe 5 to 10 times, which should allow the engine to start. Think of it as a mechanical equivalent of an electric started for bigger planes. In regards to these, they'll fit any .049 or .051 with a hex drive plate (the bit the prop screw goes into). There are round and hex types and you need a hex type for the little plastic bit to sit on to the torque is transferred to the drive plate. Older styles of spring starters had a little hook that you put on the prop itself and the pushed the prop directly rather than the drive plate. You can check out the video linked below to get an idea of how it works. [link=http://www.sturmtech.com/rc/videos/testors_camel.wmv]Camel test run[/link]
Posted on: 9/17/2009 9:45 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9102886
RE: A little 3D - Laminar Yak for .074
I had a Taco too. I've never run a 25FX, but if you ever run across a GMS 32 you might give it a try. Same weight as most 25s and is really a nice running engine. Good power and the one I have has good throttle response as well. I understand you guys on the 'house payment' planes. I love the big stuff, but don't get low and slow without getting nervous. 50cc is the biggest I've gone and even then my enjoyment is limited by the constant awareness of exactly how much $$ is going around up there.
Posted on: 9/14/2009 4:29 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9095266
RE: 1/2a B-29 AP.061 X 4 ????
CP, did you include any offset thrust on your twins? One of the recommendations I've seen several times is to put in some offset on the engines towards the wing tip to help counteract the loss of an engine. You'll obviously get some power degradation from not having true thrust lines, but should help with engine out situations. Duke
Posted on: 9/14/2009 4:20 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9095241
RE: A little 3D - Laminar Yak for .074
What is really noticeable for me is just how much more stable things are for 3D the bigger you get. I fly 1/2a and I'm on the sticks like crazy 100% of the time, my Mojo 25 is less, Mojo 60 even better, and the big 50cc Edge more stable. What goes up for me in the pucker factor and I still have to overcome that. Pics below are of my Mojo 60 w/Saito 100. A long way from 1/2a but a super stable platform for 3D.
Posted on: 9/13/2009 10:37 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9093480
RE: A little 3D - Laminar Yak for .074
I'm only a fair 3D flyer, I do fly a lot of larger profile 3D, but the 1/2a bug is never too far away. The original .074 piston/liner was the victim of a mistake by myself, I was messing with the throttle linkage and took the needle out one night. Then when I put it back in, I meant to run it the next day to reset it. But forgot and put the plane in the air without messing with the needle. So ended up with a one really lean run. The other piston and liner weren't really shot, but there was noticeable loss of compression. Since I figured this plane definitely needs as much oomph as I can get, I swapped out to the new P/L set. I've built a couple of halfwits and they were real fun.
Posted on: 9/13/2009 12:24 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9091863
RE: 1/2A THRUST-O-METER
[quote]ORIGINAL: combatpigg I agree that the MAS is the better choice here. There's other examples where the MAS seems better than APC. I swear that right now the MAS 6x4 cut down to 4.2'' pulls better than the APC 4.2x4. I was ''making'' MAS 4.2x4s before I knew about the APC product, but then flocked to APC like a good little lamb until recently. In the last few outings I've compared the 2 props 1 flight after the other and like the cutdown MAS slightly better. On a different airframe, different rpm regime, who knows? [/quote] CP, The performance of the cut down MAS compared to the APC is probably all in the tip shape. APC has narrow little tips with reduced pitch, while your cut down MAS has big old paint stirrer tips at more or less full pitch. So larger effective prop chord and higher pitch out at the tip wins. (or at least it sounds good) Got an APC 7x3 on the .074 for the little yak I built, need to grub around in the box for a MAS 7x3 and see how that does. Duke
Posted on: 9/11/2009 1:41 PM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9087093
RE: A little 3D - Laminar Yak for .074
Andy, The reg I'm using is actually set up for 6V for max performance from the HS-65s. The voltage is less important than the method. What you're doing effectively is using a transformer to step up the voltage and I'm using a switching reg to drop the voltage down. In my setup, the reg sees 7.4V most of the time and basically switches the battery in and out of a capacitance circuit to maintain 6V. In power terms if I draw say 2.0 amps average working my servos hard (which is possible with the 3D manuevering in portions, maybe even up to 3 to 4 amps in very short bits with hard control inputs), then I'll be drawing an effective 12 watts (6Vx2A) for that time, which will still be 12 Watts seen at the battery side. To step up the voltage you're effectively using a transformer type setup to raise the voltage. If I was using that setup, then my reg would see 3.7V most of the time and would output 5V, so if I was drawing 2A, that would be 10 watts out. The 10 watts has to come out a single cell this time which is only supplying 3.7V, so the effective amp draw is 10/3.7=2.7A (approx). So there's probably no practical difference between stepping up to 5V from 3.7V and switching down to 6V from 7.4V in terms of flight performance, you can run a bigger cell so the extra amp draw probably won't hurt and your setup will probably be lighter over all. The only question would be ability to handle surge loads from both the battery and the reg side. In effect, my setup weighs exactly the same as using a 4C 350mah nimh pack w/switch (about 44 grams) and is more robust in terms of surge loads than the nimh. You should be able to get in the 24 gram range on the same size lipo with the smaller DC-DC converters, but I would check the output power of the converter and make sure it's apropriate for what you need. On the .074, I'll be running a block stock APC 7x3 initially on 20% fuel (synth/castor blend). I just swapped to a new cylinder/piston set so I need to do some break in before I tach it for performance, but I expect the numbers to be reasonable.
Posted on: 9/11/2009 8:48 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9086447
A little 3D - Laminar Yak for .074
Been working on this off and on for a bit and finally got the baby lamyak 90% stuffed. All servos in, linkages done, engine mounted, throttle servo in. Just need to add tank, RX and battery (350 mah 2s lipo with regulator). Current weight is right at 15 1/2 ounces, and I figure I'll be right at 18 1/2 ounces dry. Still look to be under 12 ounces per square and even at 18 1/2 to 19 ounces total the .074 should pull it around fine. Won't be a rocket pull out but should do ok. I'm looking to finish it up for a school yard maiden on Sunday. Plane is a Yak design with laminar wing done by a guy on the ProBro site which I sized down for the .074. Duke
Posted on: 9/11/2009 2:22 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9086144
RE: HELP / QUESTION MECOA PARTS for NORVEL AND WASP/AP .061 MOTORS
Nelson plug and adapter would also be a good choice.
Posted on: 8/28/2009 9:38 AM by Author "Dukester"
in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=9051602
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