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WWhunter
09-25-2014, 07:26 AM
I have been looking at a couple of older uncompleted Kitfoxes and seem to be seeing these older models have a GSC propellor. I do remember them from years ago but to be honest, I haven't heard much about them in a long time.
So, my question is, are these a decent prop or are they pretty much regulated to hangar wall art?
One of the planes I am looking at is 20+ years old with 0 hours on the engine/prop. Being a wood prop and no maintaince done I am wondering if this prop is still good. Stored indoors I doubt it was hurt at all but one never knows.

Av8r_Sed
09-25-2014, 11:36 AM
Pretty much wall art. GSC recommends replacement blades at 5 years IIRC.

WWhunter
09-25-2014, 01:08 PM
WOW!!! Bummer. Even though it has never been used it is trash? I guess that is just another addition to the list of negatives I am accumulating on the purchase of this 'fox. :(

jrevens
09-25-2014, 02:15 PM
Pretty much wall art. GSC recommends replacement blades at 5 years IIRC.
Wouldn't that be 5 years of use, Paul? Surely the blades don't deteriorate like spoiled meat?

mr bill
09-25-2014, 02:18 PM
Can't help wondering if 5 years is the only factor. Other wood props have no such restrictions. I would not give up on it yet. I would give the factory a call and see what they say.

jrthomas
09-25-2014, 02:23 PM
Not so fast. A friend bought a model 2 that had never flown after it was finished and sat for about 20 years. It had a 582 with the GSC 3 blade. Between me and my buddy, we flew the pants off it for a couple of years with no problem. Another friend had a Kolb III with a 582/GSC. The blades started changing pitch, turning in the hub. I really couldn't blame the prop. The Kolb sat outside in the weather for several years. We figured the wood blades would swell and shrink with the weather. GSC props are not my 1st choice but there's a bunch of them flying that have given good service. They seem to pull pretty good and perform fairly well. They just need some extra care. James Thomas

Jono
09-25-2014, 03:17 PM
No problems with ours so far, admittedly always hangared and flown in good weather only. I vaguely remember Dad telling me that the GSC prop is good for 5 Years or 500 hrs (whichever is sooner).

I've read lots of comments about certain props being on the heavy side for Rotax gearbox limits, does anyone know how the 3 blade GSC prop stacks up, is it on the heavy / light side?

DesertFox4
09-25-2014, 03:40 PM
Mine became wall art after 300 hours of total time in use. One blade started to turn in the hub while in flight reducing my rpms to 4900 wide open throttle on the 912ul. We checked proper torque and it was spot on but if you do over torque the blades they are damaged and failure is possible.
When I went to removed my GSC prop, all three blades had black tape on the hub ends to make the aluminum hub grip the blades better. Indications of one of the previous owners having had problems with the blades staying put.:eek:


I gave up and bought an IVO and never looked back.

They are nice looking props though so attach an electric motor and hang it in your shop or hangar for a nice overhead fan.

Jono
09-25-2014, 03:49 PM
Ahh...yes.... I do remember that we had the hub machined down a few thou (or there abouts) during the build process to give a better clamp as per someones recommendation.

SkySteve
09-25-2014, 06:24 PM
I use my old GSC prop everyday ....... as exterior wall art for my shop:
http://i237.photobucket.com/albums/ff12/KitfoxSteve/66022410-A6E0-4109-87AB-7FC8E1E2DE26.jpg (http://s237.photobucket.com/user/KitfoxSteve/media/66022410-A6E0-4109-87AB-7FC8E1E2DE26.jpg.html)

Peteohms
09-26-2014, 07:41 AM
Here is how to mount your GSC propeller.

DesertFox4
09-26-2014, 10:37 AM
Steve and Pete, nice photos and as I said , they are great looking props.

Actually with proper care and following the manufacturer's recommendations , you can safely fly them. I just don't like to work that hard to change pitch on a prop then worry if I damaged the blades.

SkySteve
09-26-2014, 11:17 AM
Pete,
The clock idea is great, but one of us has the prop mounted upside down. It must be you!:D

jrevens
09-26-2014, 11:22 AM
Yeah, just like a horseshoe, Steve, yours is holding all the luck! ;)

JimS
09-27-2014, 10:55 AM
I would inspect it closely, ground run it for the one hour engine break-in period, check it over again, retorque and fly it if it still looks OK. Flew mine for 8 years and 500 hours and it worked great. Very smooth on the 582. Changed to a PowerFin not because of anything wrong with the wood prop but I wanted a prop that would handle a bit of rain better. My plane was garaged in a climate controlled environment but if yours was stored indoors I would think it would be OK.

Peteohms
09-27-2014, 06:23 PM
Pete,
The clock idea is great, but one of us has the prop mounted upside down. It must be you!:D


You see Steve, this prop was once on an Aussie Kitfox. So, that's why it's mounted upside down.

SkySteve
09-27-2014, 09:08 PM
Perez,
Yep. Got it. It all makes sense now.

Paul Z
09-28-2014, 09:07 AM
You see Steve, this prop was once on an Aussie Kitfox. So, that's why it's mounted upside down.

I thought the rotation was reversed when south of the equator!

mr bill
09-28-2014, 09:20 AM
That is only for sinks, bathtubs and toilets.

Greensuiter86
09-29-2014, 06:39 PM
If the prop was stored protected from the elements you shouldn't have any problem. Tell tail signs of potential issues are hazing of the clear coat, any visible cracking or delamination in the wood grain, or dark spots which may indicate mold or rot. If I were concerned, personally it would be worth it to me to send it in and have it inspected professionally. When you weigh the potential risk and costs from the damage that may occur if it failed in flight, the cost of shipping and inspection doesn't look that bad.... That being said, I know lots of guys who have been flying wood GSC props that are decades old with hundreds of hours on them without issue and am personally flying with a 3 blade 66" right now with confidence.

Good luck,

Dusty
10-22-2014, 11:08 AM
Gsc prop 1000+hrs 21 years old on a kf3 582 other than a sand back & rebalance been a good prop .
Recently fitted an airplast echo prop ,wouldn't go back,8kts faster for the same revs,
Now making73kts at5500 (pitched 5800 static)

WWhunter
10-22-2014, 07:51 PM
What is this Airplast proplellor you speak of? I tried my friend 'google search' and found next to nothing other than it is French. Could you please elaborate more on the prop.
Thanks

Paul Z
10-22-2014, 08:29 PM
And a nice shop it is, that prop looks like it had a rough landing! ;)


I use my old GSC prop everyday ....... as exterior wall art for my shop:
http://i237.photobucket.com/albums/ff12/KitfoxSteve/66022410-A6E0-4109-87AB-7FC8E1E2DE26.jpg (http://s237.photobucket.com/user/KitfoxSteve/media/66022410-A6E0-4109-87AB-7FC8E1E2DE26.jpg.html)

Dusty
10-22-2014, 09:50 PM
At the risk of getting off topic airplast helice is French ,limited info on line .
I believe mine was on a Foxconn terrier Subaru powered? Very well made!
The gsc prop if kept out of the weather should be no problem
The loose clamping referred to would be a reason for immediate retirement,machining the hub NO WAY!

WWhunter
10-23-2014, 05:01 AM
Dusty, I wanted to say welcome to the forum!! If you would, you could start another topic with info on your new prop. I am sure there are others besides me that would like to hear what you have to say about it.
Keith

SkySteve
10-24-2014, 08:25 AM
And a nice shop it is, that prop looks like it had a rough landing
Paul, Yes, the landing was a little rough, but very, very short.:eek:

P Morel
10-26-2014, 09:55 AM
Nice pic of the prop!

jonstark
08-10-2015, 10:34 AM
Gsc prop 1000+hrs 21 years old on a kf3 582 other than a sand back & rebalance been a good prop .
Recently fitted an airplast echo prop ,wouldn't go back,8kts faster for the same revs,
Now making73kts at5500 (pitched 5800 static)

I'm Just about to rig my GSC. Can you tell me what would be a good starting pitch for first run on my 582?

thx,
Jon

Paul Z
08-10-2015, 10:50 AM
I found this on the GSC Website that would be a good starting point. http://www.ultralightprops.com/gsc_systems/pitchset.htm

Dusty
08-10-2015, 01:24 PM
I don't have the pitch settings for my gsc but my airplast prop on a 3:1 gearbox
17.5degree at the tip=5200static (prop stalling?)

15.5 degree =5800static


14.5degree=6000static
I run slightly over pitched and the airplast is marginally smaller giving a better cruise at the expense of a little less initial acceleration.
Possibly try14degree initially and adjust from there(1degree is around 200rpm)
Don't rely on the original tachometer ,use a tiny tach or similar .
Pitch change is no big deal using the clamp on protracter.
Make a wooden tool that slides over the prop blades to get better leverage
(Like a crescent spanner with an airfoil cutout)this makes accurate movement easier
Don't attempt to fly under pitched as your egt's will go ballistic! If they are high on test flight, just pull them back using a little choke to get you back to base!

dholly
08-10-2015, 06:31 PM
My KF3 had a 582 mod 99 w/ 2.62:1 C-box and 68" GSC Tech III prop. Best set to 13.5* to 14* degrees, IIRC.

jonstark
08-11-2015, 01:16 PM
GSC talks about a fixture to slide up the prop blade to give the correct blade station for angle measurements. How far from the hub or tip do you folks measure the blade angle without this tool?

Jon

t j
08-11-2015, 08:41 PM
The 21 year old instructions I have for a GSC 3 blade prop say to place the protractor at 75 per cent of the distance from the hub center to the tip of the blade. Mine was a 68 inch prop so I set the protractor at 25.5 inches from center of the hub.

Olle1975
09-03-2015, 02:30 AM
582 Mod. 90 Greyhead with 68" GSC and C-Box (I think 3:1) with GSC-Tool at 75% 18 Degree Pitch. Round about 5800 rpm static.

Olaf

Monocock
10-01-2015, 09:17 PM
I've recently replaced my 66 inch GSC three blade on my 582 for an IVO.

The figures speak for themselves;

GSC
Static 6200
Climb 700 fpm
Cruise (5200 rpm) 68 mph.

IVO
Static 6200
Climb 900 fpm
Cruise (5200 rpm) 83 mph.

Mk 3 with C box. All figures quoted above are solo.

Dusty
10-02-2015, 12:44 PM
The GSC numbers are very similar to what I was getting
The IVO numbers are impressive,that's 72 kts! At 5200.
I need 5700 to get that with my draggy 3.
New tech v's old school perhaps?

ohlhausenr
10-03-2015, 07:32 AM
Monocock, do you have a ultralight or medium IVO prop for your 582 Rotax?
Thanks,

Monocock
10-03-2015, 07:48 AM
Ultralight.

There's two blade pitches to choose from in the Ultralight range; standard or coarse. Mine are standard blades. If you go for a shorter IVO you might need the coarser Ultralight blades.



http://s6.postimg.org/z38gzgrz1/image.jpg (http://postimg.org/image/z38gzgrz1/)

Monocock
10-03-2015, 08:56 AM
PS Sorry to hijack a GSC thread with IVO stuff, but if anyone is out there wondering whether to buy a GSC, I really wouldn't bother. They might look pretty, but they're so incredibly inefficient. My results aren't unique to me either. Both 582 powered Foxes I've had have had IVO's and they both completely woke up with them. Friends I have advised to buy one have found the same too.

jonstark
08-30-2016, 02:11 PM
What weight difference is there between the GSC and the different IVOs? My wt&bal says I could use some more weight up front.

Jon

LSaupe
08-31-2016, 02:09 AM
I have been trying to get that myself. I will be swapping my GSC with an IVO whenever it shows and will post some weights.

My understanding (unconfirmed) is that the GSC weighs around 3 lbs more than the Ivo in case that helps at all.

LSaupe
08-31-2016, 02:12 AM
Monocock:

What blade diameter did you choose and what is your gearbox ratio?

Olle1975
05-23-2017, 07:48 AM
Hi at all,

I had a chance to test my GSC 68" 3 blade and a Warp Drive 68" at my Kitfox III with 582 and 3:1 Ratio C-Box.
Both Propeller had 5900-6000 static - GSC 18 degree at 75% and Warp 13,5 degree on tip.

I like my GSC with about 180hrs and 4 years, it looks like the first day and performance well.

May be someone notice the same performance or could recommend a better prop than GSC? I'm looking for a
nice two blade or 3 blade prop if it works with my gearbox and gets a better Performance than this - any ideas?

https://www.youtube.com/watch?v=ilJzHAz7P_Y

Take care....

Olaf

LSaupe
05-25-2017, 05:18 PM
I have been quite happy going from my 3 blade 68" GSC to the 3 blade 68" Ivo. My gearbox ratio is 2.6x though. Much smoother and lighter than the GSC. Performance though similar (maybe 4 mph faster across the board with the IVO).

Olle1975
05-26-2017, 08:15 AM
Did you try to convert your 3 blade IVO in a 2 Blade Prop? I've read that's possible with an IVO-Prop?

Olaf