Today's Message Index:
----------------------
1. 03:23 AM - wing problem (william sullivan)
2. 04:04 AM - Re: wing problem (pj.ladd)
3. 05:14 AM - Kolb List Re: wing problem (william sullivan)
4. 05:52 AM - Re: 4 stroke in a kolb (KOLB AIRCRAFT)
5. 05:59 AM - 2 new Kolb Owner/Pilots (Jim Kmet)
6. 08:16 AM - Re: 2 new Kolb Owner/Pilots (Russ Kinne)
7. 08:16 AM - Re: 4 stroke in a kolb (jb92563)
8. 08:43 AM - UltraStar engine woes nearing a conclusion (jb92563)
9. 08:46 AM - Re: Re: Just another idea...Vtwin firestar? (Richard & Martha Neilsen)
10. 09:17 AM - Re: UltraStar engine woes nearing a conclusion (robert bean)
11. 09:55 AM - Re: UltraStar engine woes nearing a conclusion (d-m-hague@comcast.net)
12. 09:59 AM - Re: UltraStar engine woes nearing a conclusion (d-m-hague@comcast.net)
13. 11:03 AM - Re: Kolb List Re: wing problem (pj.ladd)
14. 12:11 PM - Re: UltraStar engine woes nearing a conclusion (robert bean)
15. 01:38 PM - Re: UltraStar engine woes nearing a conclusion (Jack B. Hart)
16. 02:15 PM - Re: UltraStar engine woes nearing a conclusion (Dana Hague)
17. 02:20 PM - Re: UltraStar engine woes nearing a conclusion (Dana Hague)
18. 03:13 PM - Re: UltraStar engine woes nearing a conclusion (Jack B. Hart)
19. 03:40 PM - Re: UltraStar engine woes nearing a conclusion (jb92563)
20. 06:03 PM - Re: Tansfer pump Ideas? (Richard Swiderski)
21. 07:10 PM - Re: Re: UltraStar engine woes nearing a conclusion (Dana Hague)
22. 10:37 PM - Re: UltraStar engine woes nearing a conclusion (jb92563)
Message 1
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Pat- Did you fix your wing problem yet, and have you test flown it again?
do not archive
Bill Sullivan
FS/KX/447
Windsor Locks, Ct.
Message 2
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| Subject: | Re: wing problem |
Pat- Did you fix your wing problem yet, and have you test flown it
again?>>
Hi Bill,
Yes thanks. I reversed the swivel fitting on the port wing attachment
enabling me to lower the trailing edge a bit more. This seems to have
done the trick. I got in a nice 80 minute cruise around the area the
night before last. Quiet evening, the wind finally changed from about 15
mph across the strip which I didn`t think I could handle at the moment
to about 5 mph straight down the runway. There was about12 mph when I
got to 1500 ft.
I still have the Hauk designed bungy trim on the stick but as she will
fly at 70mph at 2650revs hands off I think that will do nicely.
Thanks everybody for their suggestions.
Cheers
Pat.
Message 3
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| Subject: | Kolb List re: wing problem |
Pat- Very good. That's a Mark III?
do not archive
Bill Sullivan
FS/KX/447
Windsor Locks, Ct.
Message 4
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| Subject: | Re: 4 stroke in a kolb |
MARK PLEASE KEEP US POSTED ,SOUNDS INTERESTING, TRAVIS.
----- Original Message -----
From: Mark
To: 'Kolb List'
Sent: Thursday, May 22, 2008 8:06 AM
Subject: Kolb-List: 4 stroke in a kolb
I have been working on a Generac conversion for my Ultrastar for
several months now. I had to rebuild the cage and am working on a motor
mount to use a direct drive version that hand props to start. There is
one currently flying in a thunder gull in Illinois with 30+ hours now.
The engine will weigh the same as the Cuyuna that was removed with 5
more Hp. I would have more progress,but I am taking care of a sick
parent(who wants to see my lawnmower engine plane fly). Mark in Florida.
Message 5
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| Subject: | 2 new Kolb Owner/Pilots |
Congrats to 2 new Kolb Pilots/Owners in Tennessee!
Bradley Stump of Harrison TN, Flew his newly completed MK-3X, (70HP
Hirth) out of his home base of Cleveland TN last week. A successfull
1st Flight.
David Meyer had his Newly aquired MK-3C (Rotax 582) airborne last
weekend at his home Base of KSRB, (Same airport I`m based at).
Both Pilots are lurkers to this list... CONGRATS GUYS!!
Jim
Message 6
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| Subject: | Re: 2 new Kolb Owner/Pilots |
Most Hearty Congrats to Bradley and David! -- lots of us lurkers are
jealous --
do not archive
On May 23, 2008, at 8:56 AM, Jim Kmet wrote:
> Congrats to 2 new Kolb Pilots/Owners in Tennessee!
> Bradley Stump of Harrison TN, Flew his newly completed MK-3X,
> (70HP Hirth) out of his home base of Cleveland TN last week. A
> successfull 1st Flight.
> David Meyer had his Newly aquired MK-3C (Rotax 582) airborne last
> weekend at his home Base of KSRB, (Same airport I`m based at).
> Both Pilots are lurkers to this list... CONGRATS GUYS!!
> Jim
>
>
Message 7
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| Subject: | Re: 4 stroke in a kolb |
The Cuyuna UL-202 weighs 58 lbs and the Cuyuna 430 weighs 65 lbs without the prop/redrive
I would be very interested in this conversion if it was in the under 100 lbs category
for my own UltraStar.
I think that puts it outside the Part 103 Ultralight category.
--------
Ray
Kolb UltraStar (Cuyuna UL-202)
Moni MotorGlider
Schreder HP-11 Glider
Riverside County, CA
Do Not Archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=184513#184513
Message 8
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| Subject: | UltraStar engine woes nearing a conclusion |
Recap:
My UL-202 was running to hot CHT's and EGT's and no amount of messing with jets
and carb needle settings could correct the problem.
Because the engine had been repaired after a seizure by the previous owner I feel
it is suspect but I got a spare Cuyuna 430 with the deal.
New:
I swapped out my Cuyuna UL-202 for a 50 hr Cuyuna 430 and it is behaving the same
way producing the same high CHT's and EGT's.
It also can not get more than 5900 rpm like the UL-202
The only conclusion I can draw is that I have to much prop loading.
Its a 50" Ritz prop, but there is no indication of pitch anywhere on it.
I figure that I will start cutting down the tips 1/2 inch at a time until I get
the RPM up to the recommended 6200-6400 range and see what CHT's and EGT temps
result.
Is there an easy way of measuring the prop pitch, or do I just get out the protractor
and a calculator and figure it out using trigonometry?
--------
Ray
Kolb UltraStar (Cuyuna UL-202)
Moni MotorGlider
Schreder HP-11 Glider
Riverside County, CA
Do Not Archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=184522#184522
Message 9
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| Subject: | Re: Just another idea...Vtwin firestar? |
Don
I agree 100% I just assumed that the engine package had been developed. Also
thought that the engine would have been balanced at the factory. Do they
fine tune the factory balance. Props also need to be balanced and redrives
sometimes need to be tuned for different props. My point is/was that with
out the prop you aren't seeing the interaction of the engine/redrive/prop.
The guy that was showing and flying the Buckeye at Sun N Fun talked about a
change in exhaust systems due to cracking. I assumed it was due to
vibrations but???? Sounds like it might be a smooth running package but?
Again this engine sounds like a potential option for a Firestar. At 2GPH the
fuel burn is super. It is hard to believe that the Genrac will perform as
well a Rotax 503 even with a redrive but with the thrust figures you are
reporting it sure would be interesting. The Buckeye at Sun N Fun was
swinging a two bladed wood 74? inch prop. One would need to configure the
installation of the engine to allow clearance for a prop that long to get
the thrust your talking about. Most of our members end up flying one of the
three bladed composite props for durability and would see less thrust with
the extra blade and shorter length.
I really like seeing computation for Rotax. Their prices have gotten way out
of hand . The HKS is widely talked about and a few of our members are flying
them but they are also very expensive.
Sure would like to see someone try it.
Rick Neilsen
Redrive VW Powered MKIIIC
----- Original Message -----
From: "Don G" <donghe@one-eleven.net>
Sent: Thursday, May 22, 2008 10:03 AM
Subject: Kolb-List: Re: Just another idea...Vtwin firestar?
>
> Rick, Yes you are right, induced vibration from a propeller will make any
> engine seem to vibrate more than with the prop off...BUT...what I am
> talking about here is engine vibration, generally measured in the X, Y,
> and Z axis on the engine only. These are much higher frequency vibes and
> can be very detrimental to an airframe. You simply cannot determine the
> vibration level of the engine with a prop...or anything attached to the
> pto. This has been a concern of anyone using a industrial V-twin with a
> redrive on it...the engine vibration.
> The progress of the development of any package like this must be first
> examined with nothing on the PTO/crank....then as you move on to attaching
> props and things, you discover which propmakers really know how to balance
> a prop...or a pulley or a shaft or a whatever the driveline consists of,
> and then address that separately. Then you deal with the "driveline
> induced vibrations"
> I know Buckeye has a whole pile of props from different manufacturers,
> they have been testing, including 2, 3 and 4 blade designs, and he did
> express some remorse with a particular mfgs props, saying that the
> differences in 6 in a row of theirs were more than the differences in all
> the mfgs put together! Since this tidbit is second hand information, I
> wont be naming names.
> I also know there are some really hard to track vibes that come from a
> prop/redrive/piston engine combination, as anyone who has fooled around
> with different combinations has experienced. This has to do with piston
> power pulses/ number of blades/ moments of inertia and prop length and
> reduction ratios. Some call it torsion resonance and I have heard it
> described a number of ways. Basically alot of fellas just lump all these
> things together, and call it engine vibration, but when you are trying to
> reduce these inertias, you must address them all separately.
>
> To speak to you wish about wishing to see it with a prop on it...I have
> seen it in a with only a couple of different props...some of them were
> smooth as silk...and some of them were just terrible! I didnt get to see
> the 4 blade powerfin run on it, but their description was "so shockingly
> smooth we couldnt believe it."
>
> BTW, for you guys thinking about the technicals of this...the redrive
> ratio is 2.25 to 1 and they are swinging a 2 blade 74 inch prop, among
> others..
>
> --------
> Don G.
> Central Illinois
> Kitfox IV Speedster
> Luscombe 8A
>
> http://www.geocities.com/dagger369th/my_firefly.htm
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=184353#184353
>
>
>
Message 10
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
Ray, pitch for "real" airplanes and us guys is two different worlds.
It would be nice to see a conversion chart (is there one out there?)
I have come to like the degree method because it is easily measurable
by the owner.
10 degrees is a fairly fine pitch, 14 and over is for the fast, high
HP guys.
I'm currently at about 11 1/2 with a 70" two blade which gives me
about 4900 on take off roll.
I'm going to squeeze it back to about (this ain't a precision deal
here folks) 10 1/2
so I can impress the runway turtles.
BB, managing to fly on 55 hp with a fat MkIII
looking nicer here now
do not archive
On 23, May 2008, at 11:41 AM, jb92563 wrote:
>
> Recap:
>
> My UL-202 was running to hot CHT's and EGT's and no amount of
> messing with jets and carb needle settings could correct the problem.
>
> Because the engine had been repaired after a seizure by the
> previous owner I feel it is suspect but I got a spare Cuyuna 430
> with the deal.
>
>
> New:
>
> I swapped out my Cuyuna UL-202 for a 50 hr Cuyuna 430 and it is
> behaving the same way producing the same high CHT's and EGT's.
>
> It also can not get more than 5900 rpm like the UL-202
>
> The only conclusion I can draw is that I have to much prop loading.
>
> Its a 50" Ritz prop, but there is no indication of pitch anywhere
> on it.
>
> I figure that I will start cutting down the tips 1/2 inch at a time
> until I get the RPM up to the recommended 6200-6400 range and see
> what CHT's and EGT temps result.
>
> Is there an easy way of measuring the prop pitch, or do I just get
> out the protractor and a calculator and figure it out using
> trigonometry?
>
> --------
> Ray
>
> Kolb UltraStar (Cuyuna UL-202)
> Moni MotorGlider
> Schreder HP-11 Glider
> Riverside County, CA
>
> Do Not Archive
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=184522#184522
>
>
Message 11
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
-------------- Original message ----------------------
From: "jb92563" <jb92563@yahoo.com>
>
> Is there an easy way of measuring the prop pitch, or do I just get out the
> protractor and a calculator and figure it out using trigonometry?
Measure the angle and do the trig.
-Dana
Message 12
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
-------------- Original message ----------------------
From: robert bean <slyck@frontiernet.net>
>
> 10 degrees is a fairly fine pitch, 14 and over is for the fast, high
> HP guys.
10 or 14 degrees... where? That doesn't tell much, as the angle varies along the
blade due to the twist. Near the root the angle is very large and near the
tip it's very small. You need to specify the radius where it's measured, from
which you can then calculate the pitch (in inches).
-Dana
Message 13
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| Subject: | Re: Kolb List re: wing problem |
That's a Mark III?>>
Xtra.
Pat
Message 14
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
The tip
On 23, May 2008, at 12:56 PM, d-m-hague@comcast.net wrote:
>
>
> -------------- Original message ----------------------
> From: robert bean <slyck@frontiernet.net>
>>
>> 10 degrees is a fairly fine pitch, 14 and over is for the fast, high
>> HP guys.
>
> 10 or 14 degrees... where? That doesn't tell much, as the angle
> varies along the blade due to the twist. Near the root the angle
> is very large and near the tip it's very small. You need to
> specify the radius where it's measured, from which you can then
> calculate the pitch (in inches).
>
> -Dana
>
>
Message 15
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
At 08:41 AM 5/23/08 -0700, you wrote:
>
>
>Is there an easy way of measuring the prop pitch, or do I just get out the
protractor and a calculator and figure it out using trigonometry?
>
Ray,
No trig is required. Using a bubble level, level the leading edge of the
blade that is being adjusted. Measure the angle to the vertical using an
incline meter across the blade tip. Adjust the blade to the new desired
change in angle. Then rotate each unchanged blade into the level position,
and repeat the change. If you have an IVO then you only have to do this
once.
To find the final pitch, repeat the blade leveling (up blade) and recorded
the tip angle to the vertical. Then rotate the blade 180 degrees, level
the same leading edge (down blade), and measure the same angle. Add the
two together and divide by two and you have the blade pitch.
Jack B. Hart FF004
Winchester, IN
Message 16
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
At 03:08 PM 5/23/2008, robert bean wrote:
>
>The tip
Still not enough... pitch is a function of blade angle and the radius where
it's measured.
Pitch (in inches) = tan(blade angle) * 2*pi*R
Many props don't have a constant pitch, so it's typically measured 75% of
the way out from the hub.
-Dana
--
Work is underway on drafting a new constitution for Iraq. Why don't we
send them ours? It worked for 200 years, and we don't use it any more.
Message 17
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
At 05:35 PM 5/23/2008, Jack B. Hart wrote:
>No trig is required. Using a bubble level, level the leading edge of the
>blade that is being adjusted. Measure the angle to the vertical using an
>incline meter across the blade tip. Adjust the blade to the new desired
>change in angle...
Jack, trig IS required to get the pitch. What you've described is getting
the blade _angle_, which is what you use for setting an adjustable prop...
what Ray needs is the pitch (in inches) of his fixed blade prop.
Ray: Measure the angle of the back side of the blade 75% of the way out
from the hub (for the standard 50" Ultrastar prop that's 18-3/4" out. Then:
Pitch (in inches) = tan(blade angle) * 2*pi*18.75
I've never measured mine, but I'm told the standard US prop is a 50X30 (30"
pitch).
-Dana
--
Work is underway on drafting a new constitution for Iraq. Why don't we
send them ours? It worked for 200 years, and we don't use it any more.
Message 18
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
At 05:15 PM 5/23/08 -0400, you wrote:
>
>Jack, trig IS required to get the pitch. What you've described is getting
>the blade _angle_, which is what you use for setting an adjustable prop...
>what Ray needs is the pitch (in inches) of his fixed blade prop.
>
Danad,
OOPS!
You are absolutely correct.
Jack B. Hart F004
Winchester, IN
Message 19
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
Thanks guys.
I sat down and crunched some numbers.
PI = circumference of circle in radians
Circumference = PI x Diameter
hence Circumference= 3.14159 x 50"
Pitch = distance advanced during 1 complete rotation not accounting for slippage
etc.
Pitch = Tan(Blade Angle @ 75% to tip) x (3.14159 x 50")
So for a 50x30 prop the angle at 75% out to the tip should be about 11 Degrees.
If I measure more than this then I know my prop pitch is definitely to high.
Being a fixed pitch wood prop the easiest solution is to cut the tips down.
The rpm should go up, and hopefully the CHT's and EGT will come down making my
engine and me happy again.
Then I can finally fly this thing and learn what flying a Kolb is all about.
--------
Ray
Kolb UltraStar (Cuyuna UL-202)
Moni MotorGlider
Schreder HP-11 Glider
Riverside County, CA
Do Not Archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=184584#184584
Message 20
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| Subject: | Re: Tansfer pump Ideas? |
Sorry if this posted twice, but I thinks I just clicked the 1st attempt int oblivion.
I'm not on the List much any more this last year or so, but here are some
thoughts on auxiliary tanks:
1) Always plumb so the aux tank drains 1st, as often you must take it to the fuel
source.
2) On my UltraStar I installed an aux tank above the engine. It fed the 2 carbs
by gravity after changing the float seat valves to gravity feed valves. I then
used the fuel pump to transfer fuel from my Ken Brock seat tank to the top
of the aux tank which had an overflow that drained back to the seat tank. I
modified the pump diaphragm with a neoprene gasket material so it would run dry
just fine. I had many trouble free hours with this system but it would have
been easier & portable if I had done what I did later with my SlingShot.
3)On the SlingShot the 2nd 5 gal tank was behind the front 5 gal, which put it
behind the cg so I modified the plumbing so it drained 1st. I drilled out the
vent holes in both tanks & installed a grommet fuel fitting. Both tanks had
a fuel pickup tube on it's top. The main tank (front) had it's pickup tube connected
to the input of the fuel pump. The vent of the front tank was connected
to the pickup of the rear aux. tank. The aux tank vent was plumbed to outside
the cockpit. With both tanks full, fuel would be 1st drawn from the aux
tank as it was feeding the vent of the main tank. When it was completely dry,
then the main tank would begin to go down. An added advantage is I only have
to top off one tank if I use less than 5 gal. If the aux tank was portable (
not so with SS) I would have put the female quick disconnect on the pickup of
the aux tank and the male coupler ( the always open kind) on the vent of the
main tank. This would preclude any way to block the vent & thus keep it fail safe.
This is a tried & tested method & it is also cheap! Email me off the List
if I did not explain this well enough. -Richard Swiderski
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=184594#184594
Message 21
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
Ray, not quite correct:
At 06:37 PM 5/23/2008, jb92563 wrote:
>I sat down and crunched some numbers.
>
>PI = circumference of circle in radians
No, radians are a measure of angles. 2pi radians = 360.
>Circumference = PI x Diameter
>
>hence Circumference= 3.14159 x 50"
Correct, but read on.
>Pitch = distance advanced during 1 complete rotation not accounting for
>slippage etc.
>
>Pitch = Tan(Blade Angle @ 75% to tip) x (3.14159 x 50")
>
>So for a 50x30 prop the angle at 75% out to the tip should be about 11
>Degrees.
No, you need to use 75% of the diameter too, you use Pi * 50 * .75 so the
angle at the 75% point (18-3/4" from the centerline) should be 14.3
(arctan(30/(pi*50*.75)).
>If I measure more than this then I know my prop pitch is definitely to high.
>
>Being a fixed pitch wood prop the easiest solution is to cut the tips down.
Be sure you balance it after you cut it!
One thing you might want to try if you're trimming the prop anyway... I'd
try it myself if I had to modify a prop ... is the tip mod described on
Jack Hart's website:
http://www.thirdshift.com/jack/firefly/firefly100.html
-Dana
--
Inflation is a result of legalized counterfeiting.
Message 22
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| Subject: | Re: UltraStar engine woes nearing a conclusion |
Thanks Dana for validating and correcting my formulas.
I'll check out those prop tips and measure my prop pitch in the morning.
--------
Ray
Kolb UltraStar (Cuyuna UL-202)
Moni MotorGlider
Schreder HP-11 Glider
Riverside County, CA
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