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jindoguy(at)gmail.com
Guest

Posted: Wed Oct 24, 2007 11:37 am Post subject: Ivo Props

Anyone running a two blade Ivo prop on a 447. Do you run it with or without the spacer blocks? I have a brand new prop. When I unpacked it, I could tell by finger calibration that the blades were thinner than the spacers. I thought they would squeeze down when the prop bolts were torqued to 200 in. lb. per instruction sheet. Did the torque and there is still a .015/.020" (calibrated eyeball) gap between the plates and the blades. The holes in the blades are loose enough that the blades move, both in the plane of prop rotation and fore and aft.  

When I called Ivo, the response was, "take out the spacers, they're just for looks". ??????

The only Ivo I have is a three blade that came on a 377 powered Minimax. Torques up just fine. I'm torn between following instructions from Ivo and putting them on the Bridgeport and milling them down. This aircraft is not mine, I'm just the delivery agent, and I'm not comfortable with either of these solutions. 



Rick

  [quote][b]

ElleryWeld(at)aol.com
Guest

Posted: Wed Oct 24, 2007 12:08 pm Post subject: Ivo Props

if it wer mine I would Mill the spacer blocks down  to match the blades thicknes 

 I had a 66" two blade IVO on a 447  for 600 hours with no problem and still going 

 But you can do what ever you want 

  

 Ellery in Maine Building MK3Xtra

  

  do not archive

  





  [quote][b]

jindoguy(at)gmail.com
Guest

Posted: Wed Oct 24, 2007 2:23 pm Post subject: Ivo Props

1. The prop is brand spanking new, shipped from Ivo within the last month.

2. I flycut .018 off one side of each spacer to fix it.



Rick



On 10/24/07,  ElleryWeld(at)aol.com (ElleryWeld(at)aol.com) <ElleryWeld(at)aol.com (ElleryWeld(at)aol.com)> wrote:[quote]     if it wer mine I would Mill the spacer blocks down  to match the blades thicknes 

 I had a 66" two blade IVO on a 447  for 600 hours with no problem and still going 

 But you can do what ever you want 

  

 Ellery in Maine Building MK3Xtra

  

  do not archive

  



    



[b]

ez(at)embarqmail.com
Guest

Posted: Wed Oct 24, 2007 2:28 pm Post subject: Ivo Props

Please call IVO.Something isn't  right. They probably sent you  the wrong block set. 

I surely would not run it that way.



Gene

On Oct 24, 2007, at 3:36 PM, Richard Girard wrote:

[quote]Anyone running a two blade Ivo prop on a 447. Do you run it with or without the spacer blocks? I have a brand new prop. When I unpacked it, I could tell by finger calibration that the blades were thinner than the spacers. I thought they would squeeze down when the prop bolts were torqued to 200 in. lb. per instruction sheet. Did the torque and there is still a .015/.020" (calibrated eyeball) gap between the plates and the blades. The holes in the blades are loose enough that the blades move, both in the plane of prop rotation and fore and aft. 

When I called Ivo, the response was, "take out the spacers, they're just for looks". ??????

The only Ivo I have is a three blade that came on a 377 powered Minimax. Torques up just fine. I'm torn between following instructions from Ivo and putting them on the Bridgeport and milling them down. This aircraft is not mine, I'm just the delivery agent, and I'm not comfortable with either of these solutions. 



Rick

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[b]

rowedenny(at)windstream.n
Guest

Posted: Wed Oct 24, 2007 4:20 pm Post subject: Ivo Props

Rick,

 This story has cured me of any chance of ever  buying another IVO prop, used to have one for the Loehle, but sold it before I  had very much time on it.

 Makes me wonder if your prop blades are the  right thickness.

 Their attitude is ridiculous.

  

 Denny Rowe

 [quote]   ---

beauford173(at)verizon.ne
Guest

Posted: Wed Oct 24, 2007 4:20 pm Post subject: Ivo Props

Richard:

  

 I have a 2 blade on a 447...

  

 The fact that IVO recommends (and sells) stainless  steel tape pieces to stick across between

 the blade base and the spacer block in order  to detect slight blade movement in the hub (if tape breaks, the  blade

 has moved) is what is known in the intel business  as an "indicator"....  It appears to 'ol Beauford that, based on this,  

 the IVO folks consider blade shifting in the  hub to be a significant and undesirable event.  If I were you, I'd want  

 100% of that 200 in/lb. directly on the blade  bases... 

  

 The rubber spacers may or may not be real players in this matter and I have often wondered  about their role....

 While assembling my prop, and noting the casual way  they fit against the blade bases, it doesn't 

 surprise me that IVO  says they are only ornamental.... just looking at  my assembly, I personally don't 

 see how they do much to fix the blade base into the hub with any precision--  it looks  to me like a blade

 would really have to shift a lot before they would  become a factor in restraining it.

  

 I'd be inclined to go along with IVO advice and put  all of the hub pressure (torque) on the blade bases... they

 are structural...(I don't think the rubber spacers  are).... and then mebbe try some torque seal between the hub and the  

 blade base to see what is moving and what is  not...

  

 Worth what ye paid fer it...

 Beauford

 FF076

 Brandon FL

 [quote]   ---

jindoguy(at)gmail.com
Guest

Posted: Wed Oct 24, 2007 5:34 pm Post subject: Ivo Props

Gene, As I said, "When I called Ivo, the response was, "take out the spacers, they're just for looks"." So much for calling Ivo.   

Once the Minimax is sold, I'll never have to deal with them again. I did go back and read the warning on the web site, apparently it's only applicable to engines with 3:1 gearboxes, so I probably could have gotten away with running without them, but now they're fixed. 



Rick



 



[quote]On Oct 24, 2007, at 3:36 PM, Richard Girard wrote: 



[quote]Anyone running a two blade Ivo prop on a 447. Do you run it with or without the spacer blocks? I have a brand new prop. When I unpacked it, I could tell by finger calibration that the blades were thinner than the spacers. I thought they would squeeze down when the prop bolts were torqued to 200 in. lb. per instruction sheet. Did the torque and there is still a .015/.020" (calibrated eyeball) gap between the plates and the blades. The holes in the blades are loose enough that the blades move, both in the plane of prop rotation and fore and aft.  

When I called Ivo, the response was, "take out the spacers, they're just for looks". ??????

The only Ivo I have is a three blade that came on a 377 powered Minimax. Torques up just fine. I'm torn between following instructions from Ivo and putting them on the Bridgeport and milling them down. This aircraft is not mine, I'm just the delivery agent, and I'm not comfortable with either of these solutions.  



Rick

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jindoguy(at)gmail.com
Guest

Posted: Wed Oct 24, 2007 5:42 pm Post subject: Ivo Props

Denny, The blades are pressed in mold, the spacers are cast in a mold, too. So I doubt anything has changed, unless their plastic molding guy has let the mold go to hell. There's no evidence of that, the parting line looks clean, so I guess that's the way they've always been. Makes me appreciate the Warp Drive and the Powerfin all the more. 



Rick



On 10/24/07, Richard Girard <jindoguy(at)gmail.com (jindoguy(at)gmail.com)> wrote:[quote] 



Gene, As I said, "When I called Ivo, the response was, "take out the spacers, they're just for looks"." So much for calling Ivo.   

Once the Minimax is sold, I'll never have to deal with them again. I did go back and read the warning on the web site, apparently it's only applicable to engines with 3:1 gearboxes, so I probably could have gotten away with running without them, but now they're fixed. 



Rick



 



[quote] On Oct 24, 2007, at 3:36 PM, Richard Girard wrote: 



[quote]Anyone running a two blade Ivo prop on a 447. Do you run it with or without the spacer blocks? I have a brand new prop. When I unpacked it, I could tell by finger calibration that the blades were thinner than the spacers. I thought they would squeeze down when the prop bolts were torqued to 200 in. lb. per instruction sheet. Did the torque and there is still a .015/.020" (calibrated eyeball) gap between the plates and the blades. The holes in the blades are loose enough that the blades move, both in the plane of prop rotation and fore and aft.  

When I called Ivo, the response was, "take out the spacers, they're just for looks". ??????

The only Ivo I have is a three blade that came on a 377 powered Minimax. Torques up just fine. I'm torn between following instructions from Ivo and putting them on the Bridgeport and milling them down. This aircraft is not mine, I'm just the delivery agent, and I'm not comfortable with either of these solutions.  



Rick

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herbgh

Joined: 10 Jan 2006
Posts: 145

Posted: Wed Oct 24, 2007 6:31 pm Post subject: Ivo Props

Rick and all

  

    Brings to mind my little bout with Ivo props... Eveyone said  that a three blade 60 inch ground adj IVO would work on my Firefly with the  447.. They were correct...A call to IVO cleared the matter up.. My blades were  labeled 10+ at the base..Meaning that they were made with a minimum pitch below  which I could not adjust for the 447.. I switched to blades that did not have  the + and all was well.. 

  

    IMHO---IVO blades are good for certain applications and likely  bad for others.. I have never had a problem flying in front of them.. with and  without the filler blocks..I use a three inch spacer..     As IVO said ...the spacers are just for looks... Herb  

  

 On Wed, 24 Oct 2007 20:42:23 -0500 "Richard Girard" <jindoguy(at)gmail.com (jindoguy(at)gmail.com)> writes:

 [quote]   Denny, The blades are pressed in mold, the spacers are cast in a mold,    too. So I doubt anything has changed, unless their plastic molding guy has let    the mold go to hell. There's no evidence of that, the parting line looks    clean, so I guess that's the way they've always been. Makes me appreciate the    Warp Drive and the Powerfin all the more. 



Rick

       	  Quote: 	
		                  	  Quote: 	
		                        

	




	


[b]

rowedenny(at)windstream.n
Guest

Posted: Wed Oct 24, 2007 6:33 pm Post subject: Ivo Props

[quote] ---

jb92563

Joined: 23 Mar 2007
Posts: 314
Location: Southern California

Posted: Thu Oct 25, 2007 7:13 am Post subject: Re: Ivo Props

Since we are talking about props, does anyone have experience with Power-Fin props?



I just wanted to hear some pro's and con's before I make a buying decision.



I'm looking for a 42" 2 blade prop with about 26 pitch ground adjustable.



Comments? Opinions?

_________________
Ray

Kolb UltraStar (Cuyuna UL-202)
Moni MotorGlider
Schreder HP-11 Glider
Grob 109 Motorglider

Do Not Archive

NeilsenRM(at)comcast.net
Guest

Posted: Thu Oct 25, 2007 8:22 am Post subject: Ivo Props

I have a 72" three bladed F model Powerfin. Between the IVO, Powerfin and 

Warp Drive. Powerfin has the lowest mass, the highest thrust, but less 

damage resistance than the Warp Drive. I don't how the IVO compares in 

damage resistance. I had a 9/16 x 2.5 inch bolt go thru my Powerfin with 

damage but it got me home from three hundred miles out. If a exhaust system 

goes thru the prop only the Warp Drive will get you home. Anything larger 

than an exhaust system will likely put an end to you flight but Powerfin 

will break off before causing redrive/engine damage.



Note! Props are like religion, people defend their props very aggressively. 

Putting on my flame retardant clothing.



Rick Neilsen

Redrive VW powered MKIIIC

---

d-m-hague(at)comcast.net
Guest

Posted: Thu Oct 25, 2007 8:47 am Post subject: Ivo Props

At 11:13 AM 10/25/2007, jb92563 wrote:

 	  Quote: 	
		  



Since we are talking about props, does anyone have experience with 

Power-Fin props?



I just wanted to hear some pro's and con's before I make a buying decision.



I'm looking for a 42" 2 blade prop with about 26 pitch ground adjustable.



Comments? Opinions?


	


As Rick Neilsen said, ditto on the damage resistance.  You pay for the 

lightweight construction.  I knew a guy who had a Powerfin on his 

MKIII.  He was constantly getting damage from small stones thrown up by the 

wheels.  He would repair the damage and keep on flying... until one day the 

prop exploded on takeoff at about 50' altitude.  From where I was watching, 

it looked like he made the classic mistake of not flying the plane first, 

instead concentrating on shutting down the engine... and stalled and 

pancaked it in from 50'.  The plane was a total loss, he had serious back 

injuries requiring lengthy hospitalization, and luckily his passenger (a 

paying customer on his first "introductory lesson", he was a BFI and the 

plane was an "ultralight trainer") wasn't hurt.



We picked up pieces of the prop all over the airport.  It appeared that 

there must have been some internal damage / delamination that was only 

masked by the surface repairs and filling he did



Not the prop's fault, perhaps, I blame the repair, but still a delicate 

prop for a pusher with the wheels in front.



I'm kinda glad I have a wooden prop on my Ultrastar.



Not sure Powerfin makes a 2 blade anyway.  I have a 48" 2 blade wooden 

adjustable from GSC on one of my PPG's, and that's definitely what I'd go 

for again if I was in the market for an adjustable.  Lighter than anything 

but a Powerfin, and less cost than any other adjustable.



                                 -Dana

--

--

But do you trust the _government_ with semi-automatic assault rifles?

jindoguy(at)gmail.com
Guest

Posted: Thu Oct 25, 2007 10:02 am Post subject: Ivo Props

Ray, I have a four blade 70" Powerfin on my HKS powered trike. Ditto to all on the lack of damage resistance. I screwed up and left my bifocals hanging on the neck or my T-shirt. They slipped off and went through the prop. They were cheapy $5 Dollar General bifocals at that. Put a 1/4" divot in one blade and an 1/8" nick in another. Mighty expensive 2nd hour in the trike. I did a field repair to keep flying that evening, then grounded the ship until I got two new blades. I like it, but if you have a robust enough gearbox,  i.e. "C" or  "E", if we're talking Rotax, I'd go with a Warp Drive for damage resistance.



Rick



On 10/25/07, Dana Hague  <d-m-hague(at)comcast.net (d-m-hague(at)comcast.net)> wrote:[quote]--> Kolb-List message posted by: Dana Hague < d-m-hague(at)comcast.net (d-m-hague(at)comcast.net)>



At 11:13 AM 10/25/2007, jb92563 wrote:

 	  Quote: 	
		  --> Kolb-List message posted by: "jb92563" <jb92563(at)yahoo.com  (jb92563(at)yahoo.com)>



Since we are talking about props, does anyone have experience with

Power-Fin props?



I just wanted to hear some pro's and con's before I make a buying decision.

 

I'm looking for a 42" 2 blade prop with about 26 pitch ground adjustable.



Comments? Opinions?


	


As Rick Neilsen said, ditto on the damage resistance.  You pay for the

lightweight construction.  I knew a guy who had a Powerfin on his 

MKIII.  He was constantly getting damage from small stones thrown up by the

wheels.  He would repair the damage and keep on flying... until one day the

prop exploded on takeoff at about 50' altitude.  From where I was watching, 

it looked like he made the classic mistake of not flying the plane first,

instead concentrating on shutting down the engine... and stalled and

pancaked it in from 50'.  The plane was a total loss, he had serious back 

injuries requiring lengthy hospitalization, and luckily his passenger (a

paying customer on his first "introductory lesson", he was a BFI and the

plane was an "ultralight trainer") wasn't hurt. 



We picked up pieces of the prop all over the airport.  It appeared that

there must have been some internal damage / delamination that was only

masked by the surface repairs and filling he did



Not the prop's fault, perhaps, I blame the repair, but still a delicate 

prop for a pusher with the wheels in front.



I'm kinda glad I have a wooden prop on my Ultrastar.



Not sure Powerfin makes a 2 blade anyway.  I have a 48" 2 blade wooden

adjustable from GSC on one of my PPG's, and that's definitely what I'd go 

for again if I was in the market for an adjustable.  Lighter than anything

but a Powerfin, and less cost than any other adjustable.



                                 -Dana

--

--

But do you trust the _government_ with semi-automatic assault rifles?  [quote][b]

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Thu Oct 25, 2007 10:01 pm Post subject: Re: Ivo Props

On a trike we have a Rotax 447 and a 2 bladed powerfin.  This prop is really nice on the 447, very quiet and smooth and lots of thrust.  We considered a warp drive, but it is just to heavy for the B box on the 447.   The hub assembly and the way it goes together is very nice, very simple and foolproof.    A 447 does not have many parts to come off, so I'm not to worried about putting stuff through the prop.  We do keep an extra blade just in case though, it was only a little extra, and if we pick up a rock we can have it flying again within half an hour  



I have a 3 blade Warp Drive on my MK III with a 912 S.   The 912-S has a is a lot more complicated, harder to catch everything in a preflight, and has a lot of stuff that can come off, and I would only want a strong warp drive on this engine. 



As far as damage to the engine, consider this.  If you have a weak prop on a plane, and you put something big through it, the prop will probably explode and OVERSPEED your engine like crazy.  So to think you are protecting your engine from damage by having a weak prop that will break is just foolish.  Chances are you will do far more damage to your engine from the overspeed than from an impact with a muffler or something similar if you have the strong warp drive prop.  If the 447 could handle the weight of the warp, we would have put a warp drive prop on that engine..



Wooden props suck, they are very weak, even weaker and more prone to damage than the powerfin.  We had a wood prop on the 447, it broke horribly with just a very slight impact by a strap bouncing off the tip, not catching, just bouncing off the tip    The wood prop was also much louder and had worse performance than the powerfin.  Wood comes loose at the hub, and changes balance with time.  The powerfin is far better in every way than a wood prop.  I would never ever buy any kind of wood prop.



Mike

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Fri Oct 26, 2007 5:08 am Post subject: Re: Ivo Props

My .02 on the IVO,



First off, Do NOT run the IVO in 2 blades without the bumper blocks... do NOT ask my why I know this is extremely hazardous even with the bolts torqued down properly..... I'm surprised that IVO said this was ok. are you sure you dialed the correct number? 



If you must run it without them, AT LEAST put the two bolts in and washer up the gap with large area AN washers. 



NO, the assembly is NOT strong enough with only the blade roots securing the works, the hub must squish on something all the way around with all 6 bolts installed....



As for the Powerfin, I've run several different sizes on various planes along with the warp drive, IVO's and a couple different woodies. Generally, the Powerfin gives the best thrust, especially the F model, due to the somewhat higher blade area than the other props. But, also because of the larger blade area, it usually runs at a lower AOA than other thinner bladed props like the IVO and warp drive, so it doesn't work as well on a faster plane unless you add more pitch or reduce diameter. 

On a slower plane like a trike with a single-surface wing, there's no better choice than the powerfin, IMO.



As for the warp drive, I'm now a complete warp drive believer. My FS II (or soon to be Bob's FS II) has a 68" warp drive on it and it's the best overall performer I've tried on the plane (I've tried the recommended 68" 3 blade F model powerfin on it and, while it had slightly better thrust than the warp, it unloads more at faster speeds than the warp does).



My titan has an IVO medium on it and it's ok. Not completely wonderful but not bad either.



As for the larger Kolbs running the 912, it sounds like the warp drive in at least 70" is the best compromise...



LS

_________________
LS
Titan II SS

jindoguy(at)gmail.com
Guest

Posted: Fri Oct 26, 2007 5:21 am Post subject: Ivo Props

Lucien, Unless someone at 1-800-367-7767 gets a charge out of answering the phone, "Ivo Prop", and somehow knew it was Ron I was going to be asking for, I'm pretty sure it was the right number. 



Rick

 

On 10/26/07, lucien <lstavenhagen(at)hotmail.com (lstavenhagen(at)hotmail.com)> wrote:[quote] --> Kolb-List message posted by: "lucien" <lstavenhagen(at)hotmail.com (lstavenhagen(at)hotmail.com)>



My .02 on the IVO,



First off, Do NOT run the IVO in 2 blades without the bumper blocks... do NOT ask my why I know this is extremely hazardous even with the bolts torqued down properly..... I'm surprised that IVO said this was ok. are you sure you dialed the correct number?  



If you must run it without them, AT LEAST put the two bolts in and washer up the gap with large area AN washers.



NO, the assembly is NOT strong enough with only the blade roots securing the works, the hub must squish on something all the way around with all 6 bolts installed.... 



As for the Powerfin, I've run several different sizes on various planes along with the warp drive, IVO's and a couple different woodies. Generally, the Powerfin gives the best thrust, especially the F model, due to the somewhat higher blade area than the other props. But, also because of the larger blade area, it usually runs at a lower AOA than other thinner bladed props like the IVO and warp drive, so it doesn't work as well on a faster plane unless you add more pitch or reduce diameter. 

On a slower plane like a trike with a single-surface wing, there's no better choice than the powerfin, IMO.



As for the warp drive, I'm now a complete warp drive believer. My FS II (or soon to be Bob's FS II) has a 68" warp drive on it and it's the best overall performer I've tried on the plane (I've tried the recommended 68" 3 blade F model powerfin on it and, while it had slightly better thrust than the warp, it unloads more at faster speeds than the warp does). 



My titan has an IVO medium on it and it's ok. Not completely wonderful but not bad either.



As for the larger Kolbs running the 912, it sounds like the warp drive in at least 70" is the best compromise... 



LS



--------

LS

FS II





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=141926#141926  [quote][b]

slyck(at)frontiernet.net
Guest

Posted: Fri Oct 26, 2007 5:32 am Post subject: Ivo Props

I have most of my Kolb time with a  3 blade 65" Powerfin.  The hub is  

very well designed

and repitching is easy.  Due to a suspected harmonic problem  

attributable to the 3 cyl suzuki

I have switched to a backup 2 blade 70" Warpdrive.  My impressions  

for comparison

are of the apples to oranges variety because of the different size  

and configuration.

The Powerfin has a wider high thrust blade but suffers with a drag  

penalty and a narrower

speed range per pitch setting.   The Warpdrive has less drag (free  

horsepower) and

longer legs.  I get more top end and still have great climb rpm.

Both are excellent props.

BTW, I stuck one of those Balance Masters contraptions behind the  

prop and it seems to

alleviate a lot of the "rum-rum".   Time will tell.

BB

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Fri Oct 26, 2007 6:05 am Post subject: Re: Ivo Props

 	  jindoguy(at)gmail.com wrote: 	
		  Lucien, Unless someone at 1-800-367-7767 gets a charge out of answering the phone, "Ivo Prop", and somehow knew it was Ron I was going to be asking for, I'm pretty sure it was the right number. 



Rick

	




Well regardless of what they told you, the hub if run with 2 blades and no other support in the gaps WILL dramatically increase the likelihood of a very expensive and possibly dangerous accident.



Again, the hub secured only with 2 blade roots is NOT strong enough to hold together reliably under the normal conditions of usage in flight. Do NOT try to fix this by torquing the remaining bolts down more than 200 in/lbs, or by installing and torquing the other two bolts with no support in the gap!



Again, do NOT ask me why I know this, tho I will merely say that I've verified this danger first-hand!



You can correct this partially, like I said, with stacks of wide AN washers as thick as the gap secured by the other two bolts to the specified torque (200 in/lbs) as a field repair. But the overall strength of the hub is still compromised somewhat and it really shouldn't be run like that all the time.



The bumbers, though, do result in a fully secured hub with no worries and the prop works great thus properly assembled...



Caveat Emptor!



LS

_________________
LS
Titan II SS

ez(at)embarqmail.com
Guest

Posted: Fri Oct 26, 2007 9:21 am Post subject: Ivo Props

IVO users,

In my opinion Lucien is right about the risks involved in running an  

IVO without the filler blocks installed.

Here is why I believe it is unsafe.

When the bolts are tightened the two bolts without the spacer blocks  

will cause the aluminum faceplate to warp. This distortion of the  

face plate compromises the "uniform" clamping pressure on the prop  

blade root.  As Lucien said this distortion can be prevented by  

stacking washers of the same thickness as the blade root.

If you do decide to run a two blade IVO without the spacer blocks or  

washers, do your lawyer a favor. Make certain you first get a signed  

approval document from IVO .

Gene

On Oct 26, 2007, at 10:05 AM, lucien wrote:

 	  Quote: 	

 jindoguy(at)gmail.com wrote:

> Lucien, Unless someone at 1-800-367-7767 gets a charge out of  

> answering the phone, "Ivo Prop", and somehow knew it was Ron I was  

> going to be asking for, I'm pretty sure it was the right number.

>

> Rick

>

 Well regardless of what they told you, the hub if run with 2 blades  

 and no other support in the gaps WILL dramatically increase the  

 likelihood of a very expensive and possibly dangerous accident.

 Again, the hub secured only with 2 blade roots is NOT strong enough  

 to hold together reliably under the normal conditions of usage in  

 flight. Do NOT try to fix this by torquing the remaining bolts down  

 more than 200 in/lbs, or by installing and torquing the other two  

 bolts with no support in the gap!

 Again, do NOT ask me why I know this, tho I will merely say that  

 I've verified this danger first-hand!

 You can correct this partially, like I said, with stacks of wide AN  

 washers as thick as the gap secured by the other two bolts to the  

 specified torque (200 in/lbs) as a field repair. But the overall  

 strength of the hub is still compromised somewhat and it really  

 shouldn't be run like that all the time.

 The bumbers, though, do result in a fully secured hub with no  

 worries and the prop works great thus properly assembled...

 Caveat Emptor!

 LS

 --------

 LS

 FS II

 Read this topic online here:

 http://forums.matronics.com/viewtopic.php?p=141935#141935

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