Posts: 6215
Joined: 12/8/2002 From: Valdese,
NC, USA Status: offline
Don't worry about holding on to it. Shoot, she was in my shop for 9 months before I got to cover and finish putting her togeather. Take a few weeks if needed and fly!
Posts: 464
Joined: 9/24/2004 From: Annapolis,
MD, USA Status: offline
Well guys, Grace and I didn't get off to a very good start today. Nah, don't worry, she's fine, no crashes or anything, but she IS playing hard to get...
First the good news...
The 270 mAh NiCAD actually cycled at 275 mAh right outta the box. I don't know when it was charged last, but considering it went 275 mAh before I charged it, it appears to be holding up fine.
The not so good news...
We somehow lost a elevator servo. While I was adjusting the pushrods and setting the trims, I noticed that when I pressed on the output shaft of the elevator servo it would go into serious jitters (back and forth to each extreme). Not wanting to take a chance, I swapped it out for a brand new HS-55 (fresh out of the box). No biggie, stuff happens...
With the FMA FS5 dual conversion receiver on board, and the Futaba 9ZAP providing the commands, we (Grace and I) headed out to the field with a pint of fuel and Ni-starter in hand. Remembering what Vicman said about run time, I only put in about 1/3 of a tank of fuel for the first flight. I fired up the SureStart (after a bit of fiddling), tweaked the needle, and set Grace free - she officially took to the air in Harwood, MD at 8:42 AM, today, 28 December 2007. A few clicks of down, a click or two of left rudder and it was smooth sailing, well almost... a couple of minutes into the flight the engine went rich and I spent the rest of the time climbing and diving trying to get the engine back up on step. When the fuel finally ran out, I was able to skip Grace across the still-frosted grass for the best landing I've made in a long time, and that really made up for the so-so flight. (It's amazing how slick castor oil and ice can be!)
Successive flights, four in all, pretty much produced the same results - fine on launch, goes rich after a couple of minutes and cycles back and forth between rich and lean. I even swapped out the MAS 6x3.5 prop for a MAS 6x3, thinking a little less pitch would help keep her up on step. No change... (OK, so it was 30 degrees out, but I didn't think that was the problem.) After spending a little over an hour and a half in the cold, I packed it up, determined to get to the bottom of the rich-lean-rich issue.
I pulled the engine off, and stuck Grace's battery on the cycler (it had 100 mAh left). When I took the engine's backplate off, I noticed that needle was a little boogered up, but what really stuck out was the reed - it had a really strong circular depression in it that couldn't possibly be sealing as well as it should, so I went ahead and put on a new backplate/reed/NVA. (I've never seen anything like it, unfortunately the picture doesn't do it justice.) I also checked the ball socket (not bad) and buttoned everything back up. It now ran and needled OK, but it was only turning about 11,500 RPM on a 6x3 and 15% nitro. Bumping the nitro to 30% and playing with shims only netted about a 700 RPM increase. Expecting more, I compared it's compression to a few other reedies that I had on the bench - the old SureStart wasn't as snappy as the others, so off came the piston/cylinder/glow head and on went new SureStart parts. After a few minutes of break-in running, she now spins that same 6x3 at 13,000 RPM - not stellar, but much better than before. It's been a while since I ran a 6x3 on a SureStart, but shouldn't a practically new SureStart turn more than 13K?
Since it'll probably be raining for the next couple of days (this morning was crystal clear), maybe I'll fiddle with the engine some more and delve deeper. There's not much original left but the crank and case, and admittedly I didn't check that too closely, but I'd hate to loose that nifty black anodized case! (Is that a Black Widow case or did someone else anodize it?)
I should probably leave well enough alone, but since one of my biggest downfalls is being somewhat of a perfectionist, I feel Grace (and those to fly her) deserve the best a SureStart can be. No, I won't be trimming/lightening the piston, or boring the venturi, or slappin' on a Galbreath head - I'm just after good, reliable power - something that was definitely missing.
Anyway, 'nuff of the bad news.. the good news is that Mike did a fantastic job of designing Grace and she really is a doll to fly. I forgot what it was like to fly such a stable airplane - what I thought were trim issues was just Grace righting herself! Launches are a breeze, and she climbs out / flies pretty much hands-off (a few times I stuck my hands in my pockets to warm them). Landings are a piece of cake and that strange little wing has a whole lotta lift and does a nice job of keeping the speed down. I can't wait to get back out there with Grace and get ya'll some pictures and video!
Posts: 6215
Joined: 12/8/2002 From: Valdese,
NC, USA Status: offline
Yeah, I always struggled with the first flight being rich to start with. So I would leave it a bit lean and everything would work fine. That was the case for all of my testing, the reedie race, and the afternoon with Hollis. Once it got running everything was good but if it got rich you learned how to do a harrier without throttle.
Posts: 667
Joined: 3/10/2004 From: New London, MN, USA Status: offline
Well if the problems persist, let me know. I have an extra Surestart or two on hand and rather than fiddle with a gremlin let's just swap it out.
The case & crank is indeed from a Widow that someone did a terrible SPI mod on. So I swapped it for a SS top end and backplate and it was turning a nice 16K on the bench. I liked the look of the black case so I gave it to Grace. I don't recall any rich running issues at that time.
Posts: 464
Joined: 9/24/2004 From: Annapolis,
MD, USA Status: offline
Just kidding... However, I did put on a new SureStart and was rewarded with 13,900 RPM right outta the bubble wrap (on 15% nitro). So... out to the field I went and had some fun.
As the pictures show, it wasn't exactly the best flying weather (wet and windy), but it was a tad warmer.
< Message edited by ProBroJoe -- 12/29/2007 5:40:12 PM >
Posts: 1033
Joined: 12/8/2004 From: OAKEYQueensland, AUSTRALIA Status: online
Looking at the "ding" on top of the firewall, it would apere Grace has suffered a hard nose in along the line, maybe why the motor is off song. Stewart
Posts: 667
Joined: 3/10/2004 From: New London, MN, USA Status: offline
Those are some great pics Joe! Did you get it up on the high rates and twist it out a little?
We cant thank you enough for putting in the considerable time and effort (not to mention a few $) in getting Grace in tip top condition. That kind of contribution is what will make this project! Hats off to ProBroJoe!
Yuu - I typically use an APC 6x3 and 25%. I believe I was using a Galbreath Head.
Posts: 1154
Joined: 5/10/2007 From: coralville,
IA, USA Status: offline
If you want it to stay nice , better keep it as far from me as possible. However the engine would run very nicely up until it slammed into the ground. . "Good with engines , bad at flying" . "Bad at math good with guns".
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Castor, its like Vitamin C for glow engines. I am not Dom from Airwolf but I do resemble him.......Unfortunately
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All Forums >> RC Airplanes >> "1/2 A" & "1/8 A" airplanes >> RE: Postal Plane Project 
RE: Postal Plane Project - 
However the engine would run very nicely up until it slammed into the ground. 
. "Good with engines , bad at flying" 
. "Bad at math good with guns". 