C-box ratios

[herman pahls 9]

I currently fly a 500 pound Model 2 Kitfox with a 582 Bluehead, 2.62 C-box, HK clutch and a 3 blade 68" ultralite IVO prop.

My current combination climbs great but I am always looking for better short field, climb and cruise performance.

I called IVO today to order their inflight adjustable system for my current prop and they suggested that I go to a

IVO 3 blade medium IFA and a 3.47 C-box if I want the ultimate climb and cruise with a Kitfox powered by a 582 with their available props.

The IFA prop would cost $2700. and a 3.47 C-box $1500.

The medium prop would add 10 pounds over the ultralight just where I do not need to add weight.

The 3 blade medium prop exceeds the inertial rating of the C-box.

IVO says they are not aware of any C-box failures due to exceeding the inertia loading.

I need some fatherly advice before spending $4200.

Any other props besides IVO I should consider?

Is the IFA feature of much value on a 582 powered Kitfox?

Thanks Herman

[Av8r3400 1178]

Sounds like a waste of money to me. I'd say put the IFA control on your ultra-light and go.

But that's just me.

[akflyer 1427]

You can change the gears in your current C box. I played around between 2.62 and 3:1 on mine. You can also go to the 72" IFA ultralight. YES, IFA make a big difference to get the max performance.

[BryceKat 125]

Herman,

On my 582 Avid mkiv, I have used both fixed pitch and a GSC ifa. The ifa is definitely the way to go on a 2 stroke. GSC is about $2k new, and simple. Rick, the owner, is a good Guy to work with. Good luck, Bryce

[herman pahls 9]

Thanks for the replys.

I want to do my part to support the economy and you are advising me not to.

I did not realize GSC made an IFA. I am committed to IVO's for now.

I ordered the IVO IFA system today to use with the ultralight prop.

I also have a IVO 3 blade 72 inch ultralight high pitch prop that came with the Bluehead and was used as a 2 blade with the 2.62

I was told this prop was intended to be used as a 3 blade with 3 to 1 box but IVO discourages this combination due to harmonics.

Leni; do you have any 3:1 gears left over?

What was your experience going from 2.62 to 3:1 ?

Are 2 blade IVO's really that bad for not being smooth?

I would like to list my low cost options and have this forum tell me what prop combination you would choose for the high altitude Idaho backcountry flying Joey (CS5 engineer) does?

1. 68"-3 blade ultralight IVO 2.62 IFA?

2. 72"-2 blade ultralight high pitch Ivo 2.62 IFA?

3. 72"-3 blade ultralight high pitch IVO 3:1 IFA? Harmonics??

4. 72"-2 blade medium IVO 3-1 IFA? This option would not be low cost but Ivo suggested because it would not exceed the C-box inertia limit.

This prop sells for $2460. I would consider this if it would generate significant better performance.

Is it realistic to tie your tailwheel to a 400 pound fish scale to compare at least static performance?

Your opinions will be appreciated.

I finally got the HACman to work after 6 weeks of this forum wondering how I could screw up something so simple.

Joey wanted to ask me if I was losing it.

Turns out that the restrictor that is to be drilled to .062 was accidently not drilled at all as sent to me.

Therefore when the HAC valve was closed the carbs were no longer vented and when the HAC valve was opened it did not work as designed.

Mark Napier suggested that the restrictor was plugged and it sure was. Thanks for the help Mark

Thanks to all

Herman

Edited 10 Jan 2012 by herman pahls

[BryceKat 125]

Herman,

I found the hacman instructions to be very lacking. The installation is pretty easy. I couldn't write any better instructions. Gerry ought to do a YouTube video.

Bryce

[ChrisBolkan 130]

Thanks for the replys.

I want to do my part to support the economy and you are advising me not to.

I did not realize GSC made an IFA. I am committed to IVO's for now.

I ordered the IVO IFA system today to use with the ultralight prop.

I also have a IVO 3 blade 72 inch ultralight high pitch prop that came with the Bluehead and was used as a 2 blade with the 2.62

I was told this prop was intended to be used as a 3 blade with 3 to 1 box but IVO discourages this combination due to harmonics.

Leni; do you have any 3:1 gears left over?

What was your experience going from 2.62 to 3:1 ?

Are 2 blade IVO's really that bad for not being smooth?

I would like to list my low cost options and have this forum tell me what prop combination you would choose for the high altitude Idaho backcountry flying Joey (CS5 engineer) does?

1. 68"-3 blade ultralight IVO 2.62 IFA?

2. 72"-2 blade ultralight high pitch Ivo 2.62 IFA?

3. 72"-3 blade ultralight high pitch IVO 3:1 IFA? Harmonics??

4. 72"-2 blade medium IVO 3-1 IFA? This option would not be low cost but Ivo suggested because it would not exceed the C-box inertia limit.

This prop sells for $2460. I would consider this if it would generate significant better performance.

Is it realistic to tie your tailwheel to a 400 pound fish scale to compare at least static performance?

Your opinions will be appreciated.

I finally got the HACman to work after 6 weeks of this forum wondering how I could screw up something so simple.

Joey wanted to ask me if I was losing it.

Turns out that the restrictor that is to be drilled to .062 was accidently not drilled at all as sent to me.

Therefore when the HAC valve was closed the carbs were no longer vented and when the HAC valve was opened it did not work as designed.

Mark Napier suggested that the restrictor was plugged and it sure was. Thanks for the help Mark

Thanks to all

Herman

Since you already have it, try the 72 inch ultralight with 2 blades and the 2.62 box. I have run that combo and it works very well. It will also work well with the IFA mechanism. It will run very smooth, and 2 blades are more efficient than 3. Heck you have the stuff and it is free to try.

One very important thing to keep in mind when setting up an IVO IFA system is to choose blade numbers and lengths so the prop is almost perfect with no pitch adjustment to start with. By that I mean the prop runs perfectly on the plane with no pich adjustment as a all around prop BEFORE setting up the mechanism to twist one way for better cruise and the other for better climb.

Anyway taking the time to mess with blade length and number BEFORE you start setting up the IFA mechanism will result in a far better performing system. The motor and gears will last much longer and the mechanism will be adjusting back and forth around a neutral pitch rather than being cranked towards one end and drawing a lot more current and mechanically stressing the system.

You might also want to consider running polyswitch self resetting fuses in leiu of the brute force circuit breaker. I posted a bunch of files on the Yahoo Avid site about setting up the system using polyswitches.

Hope this helps.

Chris

[herman pahls 9]

Chris

I appreciate your info on Yahoo and like the Polyswitch idea

Digikey is still in business and how can a Polyswitch only cost 56 cents.

On Yahoo you listed polyswitches with several different hold amps and 2 voltages.

Do you mind telling me which polyswitches amp ratings you were successful with and I will order.

Are the indicator lights Radio Shack items?

I have been flying with an IVO prop for years and am curious how the IFA feature will work.

When ever I reduce pitch with the ground adjust feature I back off on the adjust screw say 4 complete turns and then add back 3 full turns to get 1 full turn pitch reduction.

If I just take one turn of pitch out there seems to be resistance or stickeon in the IVO adjustment rods so that I really do not get 1 full turn of pitch reduction.

Also there is slack in the adjustment cams when reversing direction.

Maybe that is due to my prop being 18 years old but it has always behaved this way and the newer IVO's may not do this.

Or do IFA Ivo's get flown at either the fine or course stops and seldom inbetween?

I understand the matching of the Ivo blades but do not follow your set-up procedure.

Do you mind elaborating.

I will try the 2 blade 72 inch IVO next.

Thanks for your time Herman

[ChrisBolkan 130]

Chris

I appreciate your info on Yahoo and like the Polyswitch idea

Digikey is still in business and how can a Polyswitch only cost 56 cents.

On Yahoo you listed polyswitches with several different hold amps and 2 voltages.

Do you mind telling me which polyswitches amp ratings you were successful with and I will order.

Are the indicator lights Radio Shack items?

I have been flying with an IVO prop for years and am curious how the IFA feature will work.

When ever I reduce pitch with the ground adjust feature I back off on the adjust screw say 4 complete turns and then add back 3 full turns to get 1 full turn pitch reduction.

If I just take one turn of pitch out there seems to be resistance or stickeon in the IVO adjustment rods so that I really do not get 1 full turn of pitch reduction.

Also there is slack in the adjustment cams when reversing direction.

Maybe that is due to my prop being 18 years old but it has always behaved this way and the newer IVO's may not do this.

Or do IFA Ivo's get flown at either the fine or course stops and seldom inbetween?

I understand the matching of the Ivo blades but do not follow your set-up procedure.

Do you mind elaborating.

I will try the 2 blade 72 inch IVO next.

Thanks for your time Herman

Hi Herman,

When you went to the Yahoo Groups Avid site did you notice that there are two folders on the subject? One folder has the polyswitch info (where to buy etc) and another folder has the circuit diagrams and copies of some emails talking about the process of setting it up and so forth including info on the polyswitch I would start with. The fact that you asked which one to start with leads me to believe you did not see both folders. Just want to make sure you have everything before we try to go any further.

Chris

[herman pahls 9]

Chris

I missed the part number of the poly switch you suggested because I did not scroll down to the end of the post.

I called Digi key and the part number RHE 450 has been replaced with RHEF 450 ND.

Only difference is the trip amps is slightly reduced to 7.8 from 8 amps.

Digi key also sells LED's.

Did I miss the part number for your reccommended LED?

I have a IVO IFA on the way and want to incorporate your changes to the system.

Thanks for the help.

Herman Pahls 541 404 6464 Oregon

[ChrisBolkan 130]

Chris

I missed the part number of the poly switch you suggested because I did not scroll down to the end of the post.

I called Digi key and the part number RHE 450 has been replaced with RHEF 450 ND.

Only difference is the trip amps is slightly reduced to 7.8 from 8 amps.

Digi key also sells LED's.

Did I miss the part number for your reccommended LED?

I have a IVO IFA on the way and want to incorporate your changes to the system.

Thanks for the help.

Herman Pahls 541 404 6464 Oregon

Hi Herman,

Great! I would recommend also ordering a few of the higher amperage versions of the polyswitch too. It's been several years now since I did all of this, but it seems I got nuisance tripping once in a while on hot days with the 4.5 amp version I originally used. Heck they are so cheap it just makes sense to have some of these around. Some people use them as their primary fuses for sub circuits in their planes. Trip time is also something to play with.

The amperage the motor draws becomes greater and greater the further off center it is operated, because it has to work harder and harder to twist the blades further and further each direction from center. IVO uses that huge breaker as the limit "switch" and a spool of wire to limit the maximum current passing through the motor while it is stopped waiting for the breaker to trip. This helps lengthen the life of the motor.

It is cheap and brute force, but not elegant. You just hold the direction switch until the motor stops and trips the breaker. Maximum current is limited by the coil of wire while the breaker heats up to trip.

Their setup works for users who have not done the work up front to optimise performance without any pitch change. I've seen where users are doing their entire pitch change range on one side of the neutral blade setting and you can see how that would be hard on the motor. It also would require a larger polyswitch. The idea is to start out so all adjustment is on either side of neutral then choose a polyswitch that does not trip the big breaker. The closer to neutral setting your blades adjust, the smaller polyswitch you will require and the longer the notor will last.

For LED's, it doesn't matter what you use. Some have built in resistors so you don't need to supply your own. Some do not. If the LED has a built in resistor, you want it to be setup for 12 V. If not the resistor value I put on the drawing will work for LED's with no resistor.

As for the hystresis you encounterd when using the manual hub, I really don't know. However, it shouldn't make much difference with the IFA hub because you will just set it to what you want within the limits, or drive it to the limits till the light comes on. IF you do end up wit hystresis you just need to set the limit a bit further out so you can go past and come back just like doing it manually.

Hope this makes sense!

Chris

[ChrisBolkan 130]

Chris

I missed the part number of the poly switch you suggested because I did not scroll down to the end of the post.

I called Digi key and the part number RHE 450 has been replaced with RHEF 450 ND.

Only difference is the trip amps is slightly reduced to 7.8 from 8 amps.

Digi key also sells LED's.

Did I miss the part number for your reccommended LED?

I have a IVO IFA on the way and want to incorporate your changes to the system.

Thanks for the help.

Herman Pahls 541 404 6464 Oregon

Oh and a couple of other things. I see you live in Oregon. I live in Tri Cities Wa. Where are you located? We may not be far apart. Also when you get the IFA mechanism there will be some plastic washers in the assembly. Use them! They compress at the end of travel each direction to absorb force rather than metal on metal impact. They help the jackscrew last longer, prevent mechanical binding and gradually increase current as the thing grinds to a stop. They are important to the operation. I think the instructions discuss this, but just so you know, they are important to the thing lasting a long time!

Chris

[SuberAvid 617]

Well I am very glad to see this discussion since it has come at the most oppourtune time. I played with my Warp Drive prop some more last weekend and flattened it out to 12 degrees. The thrust and climb was significantly better but the cruise sucked; plus I started to push my EGT and CHT limits, but that will require some richer jetting and probably a Hacman for the Bing 64's on my Subaru.

What it did convince me of was the value of having an IFA prop so I bit the big one and ordered an IVO medium 72" IFA. I have not looked at the postings Chris did on the Yahoo Avid site yet but will do that. I am totally unfamiliar with the IVO prop since I have only had Warp Drive props. From what Chris is saying to set the prop up at the best compromise between climb and cruis with the IFA in the middle of the travel sounds very good. What I am not familiar with is how do you do this? This is probably a stupid question but can you adjust the prop like it is a ground adjustable prop independent of the IFA and that setting can then be set at the middle of the IFA adjustment range?

I hope I like this thing; they sure are not cheap!

[herman pahls 9]

Chris

I live near Coos Bay on the southern Oregon coast.

I am familiar with the Tri Cities area since I went to college in Walla Walla.

Can you tell me more about the elevator rod end safety back-up you designed.

Is the rod end failure common because the Kitfox has a very similar push rod for the elevator?

Randy

Did you go with the 2 or 3 blade medium?

Does your Subaru make similar power to a 912S?

I have been surprized when I hear of 912 owners using the IVO ultralight seris.

My be those were the 80 HP 912's.

I cannot answer your IFA questions because I also just ordered the IFA system for my current IVO prop.

Chris has posted great info on Yahoo.

I hope you will report your IFA results.

Thanks Herman

[ChrisBolkan 130]

Well I am very glad to see this discussion since it has come at the most oppourtune time. I played with my Warp Drive prop some more last weekend and flattened it out to 12 degrees. The thrust and climb was significantly better but the cruise sucked; plus I started to push my EGT and CHT limits, but that will require some richer jetting and probably a Hacman for the Bing 64's on my Subaru.

What it did convince me of was the value of having an IFA prop so I bit the big one and ordered an IVO medium 72" IFA. I have not looked at the postings Chris did on the Yahoo Avid site yet but will do that. I am totally unfamiliar with the IVO prop since I have only had Warp Drive props. From what Chris is saying to set the prop up at the best compromise between climb and cruis with the IFA in the middle of the travel sounds very good. What I am not familiar with is how do you do this? This is probably a stupid question but can you adjust the prop like it is a ground adjustable prop independent of the IFA and that setting can then be set at the middle of the IFA adjustment range?

I hope I like this thing; they sure are not cheap!

Hi Randy,

The way you determine the best starting point is to mess with blade number and blade lenghth. There is one other parameter too, and that is the base pitch the prop comes from the factory with. I seem to remember IVO makes flat and coarse balde sets for at least some of the models, but but they should be sending you the right base pitch for your HP and RPM. Blade number is the coarse setting and hopefully will get you in the ballpark. Blade length is done by shortening the blades (hard to do when you spend that much money!) So let's say you start out with three blades. You assemble the prop and make sure that the mechanism is not twisting the blades at all. Pretty easy to do, you just rotate the blade adjuster on the jackscrew when you are assembling it. Then try it out. If it is a bog fest try two blades the same way with neutral setting. If one of those combos works or is reasonably close, go with it. If three blades is a bog fest and two blades is a rev fest you will need to go back to three blades and start cutting off the tips in small increments like an inch or so till you get it right. I personally never had to cut blades because I had two blade sizes to play with as someone had already cut one set down to 68 inches. You only need to be close. Obviously if you are anywhere even in the ballpark you probably won't want to cut your blades even though it is recommended practice by IVO. It should be pretty obvious if you need to cut the blades down or if you can get by with just two or three blades. If neither is even remotely close you may have to cut. Just cut the minimum off because you or the next owner of the prop can always cut more off, but you can't add!

Obviously cutting is the last resort. Hopefully 2 or three will get you in the ballpark. You only need to be in the ballpark.

Chris

[ChrisBolkan 130]

Chris

I live near Coos Bay on the southern Oregon coast.

I am familiar with the Tri Cities area since I went to college in Walla Walla.

Can you tell me more about the elevator rod end safety back-up you designed.

Is the rod end failure common because the Kitfox has a very similar push rod for the elevator?

Randy

Did you go with the 2 or 3 blade medium?

Does your Subaru make similar power to a 912S?

I have been surprized when I hear of 912 owners using the IVO ultralight seris.

My be those were the 80 HP 912's.

I cannot answer your IFA questions because I also just ordered the IFA system for my current IVO prop.

Chris has posted great info on Yahoo.

I hope you will report your IFA results.

Thanks Herman

Hi Herman,

It must be another Chris that messed with the Rod end stop, because thiat doesn't ring any bells.

Chris

Chris

[SuberAvid 617]

Hi Randy,

The way you determine the best starting point is to mess with blade number and blade lenghth. There is one other parameter too, and that is the base pitch the prop comes from the factory with. I seem to remember IVO makes flat and coarse balde sets for at least some of the models, but but they should be sending you the right base pitch for your HP and RPM. Blade number is the coarse setting and hopefully will get you in the ballpark. Blade length is done by shortening the blades (hard to do when you spend that much money!) So let's say you start out with three blades. You assemble the prop and make sure that the mechanism is not twisting the blades at all. Pretty easy to do, you just rotate the blade adjuster on the jackscrew when you are assembling it. Then try it out. If it is a bog fest try two blades the same way with neutral setting. If one of those combos works or is reasonably close, go with it. If three blades is a bog fest and two blades is a rev fest you will need to go back to three blades and start cutting off the tips in small increments like an inch or so till you get it right. I personally never had to cut blades because I had two blade sizes to play with as someone had already cut one set down to 68 inches. You only need to be close. Obviously if you are anywhere even in the ballpark you probably won't want to cut your blades even though it is recommended practice by IVO. It should be pretty obvious if you need to cut the blades down or if you can get by with just two or three blades. If neither is even remotely close you may have to cut. Just cut the minimum off because you or the next owner of the prop can always cut more off, but you can't add!

Obviously cutting is the last resort. Hopefully 2 or three will get you in the ballpark. You only need to be in the ballpark.

Chris

Thanks Chris, that is good info. I expect that IVO will provide assembly instructions. I didn't tell them what base pitch I wanted but I did tell them the HP and redrive ratio so I expect they will send the blades that should work best with my setup. I ordered a 3 blade 72" prop. I wasn't planning to cut the blades down because I want to maximize the takoff and I am not so hard on the cruise if I can get 80+ mph. I have the 72" warp drive on my plane now and it gives good performance on takeoff when at 12 degrees and about 82 mph at 3800 rpm cruise when set at 14 degrees. I am hoping I can duplicate at lease these ends of the range with the IVO with the luxury of having both at once. If the blades they send dont seem to get me in the range, I hope they would trade them for a different pitch rather than just cutting them down.

Thank you for the infrmation on the switch circuit and prop setup you posted on the Yahoo site. I printed it out yesterday. I asked IVO if the prop had a position indicator and was a little stunned that they said no. Your circuit does exactly what I wanted so I will order those parts and build it that way. Much appreciated.

I am sure I will have other questions as I go along; such as how to explain the $2800 bill on the credit card to the wife.

Trying it as a 2 blade will be interesting too.

[SuberAvid 617]

Chris

I live near Coos Bay on the southern Oregon coast.

I am familiar with the Tri Cities area since I went to college in Walla Walla.

Can you tell me more about the elevator rod end safety back-up you designed.

Is the rod end failure common because the Kitfox has a very similar push rod for the elevator?

Randy

Did you go with the 2 or 3 blade medium?

Does your Subaru make similar power to a 912S?

I have been surprized when I hear of 912 owners using the IVO ultralight seris.

My be those were the 80 HP 912's.

I cannot answer your IFA questions because I also just ordered the IFA system for my current IVO prop.

Chris has posted great info on Yahoo.

I hope you will report your IFA results.

Thanks Herman

Hi Herman, It sounds like you are enjoying your plane with the 582 and like all of us; never quite satisfied with it the way it is.

I ordered the 3 blade medium 72" Ivo based on Ron's advice at Ivo. I was considering the 74" but he thought the 72" would be best. I do plan to try it as a 2 blade per Chris's suggestion just to see how it performs. It is all a little hocus pocus to me on what is the best for performance so I guess I will only know for sure if I try different combinations. The subaru is supposed to be turning out right at 100 hp according to Stratus. They plane the heads to get 9:1 compression, regrind the cam to a different profile and replace the intake and carb with a dual intakes and Bing 64's set up like the Rotax 912. I built my own exhaust for it out of mandrel bent tubing into a 1 1/2" FMP muffler and used a RAM dual ignition distributor.

I suppose you could get good perfoprmance out of the IVO Ultralight props on a 100 hp motor right up until something broke. IVO says to use the Medium prop and that is what Ron said when I was talking to him also. I am not sure how smart it is to go against their recommendation on that.

I look forward to your reports on your prop as well.

Randy

[ChrisBolkan 130]

Hi Herman, It sounds like you are enjoying your plane with the 582 and like all of us; never quite satisfied with it the way it is.

I ordered the 3 blade medium 72" Ivo based on Ron's advice at Ivo. I was considering the 74" but he thought the 72" would be best. I do plan to try it as a 2 blade per Chris's suggestion just to see how it performs. It is all a little hocus pocus to me on what is the best for performance so I guess I will only know for sure if I try different combinations. The subaru is supposed to be turning out right at 100 hp according to Stratus. They plane the heads to get 9:1 compression, regrind the cam to a different profile and replace the intake and carb with a dual intakes and Bing 64's set up like the Rotax 912. I built my own exhaust for it out of mandrel bent tubing into a 1 1/2" FMP muffler and used a RAM dual ignition distributor.

I suppose you could get good perfoprmance out of the IVO Ultralight props on a 100 hp motor right up until something broke. IVO says to use the Medium prop and that is what Ron said when I was talking to him also. I am not sure how smart it is to go against their recommendation on that.

I look forward to your reports on your prop as well.

Randy

I think 80 HP is the dividing line for UL to MED IVO props. For 65 HP I hear UL is right, for 80 HP either works and for 100 HP MED becomes mandatory.

Interestingy, we set up a friends 80HP Kitfox Vixen with the UL IVO, and on startup and shutdown, the prop blades looked like spaghetti as they flexed around from the compression impulses. Those UL blades looked like a whip cracking. I think if it were me personally, I'd run the UL on the two stroke Rotax and leave the medium for the four strokes even 80 hp.

[ChrisBolkan 130]

Hi Herman,

When I logged on today a message popped up from you about the polyswitches. I hit reply, but the message text went away. I thought I was posting, but aparently not. So I lost your questions other than what I remember. Since I am not very good at this forum, how about if you post rather than message me on the board, because I don't know how to do that?

From what I remember, soldering extensions onto the polyswitches is fine, and maybe desirable since they are solid wirer and subject to vibration. little multi wire extension leads would allow vibration without fatiguing the leadwirers. You probably got the PC mount version of the polyswitch instead of the leaded version. No big deal.

The long coil of wire that come with the prop is to limit current flowwhen the motor is stopped waiting for the breaker to blow. Losing an inch or even a foot of the 10 or 20 feet won't make any real difference. I do not even thing the coil of wire is necessary once using the polyswitches, but I figure the least you mess with the original it is easier to go back to original if you want to.

Chris

[herman pahls 9]

Hi Herman,

When I logged on today a message popped up from you about the polyswitches. I hit reply, but the message text went away. I thought I was posting, but aparently not. So I lost your questions other than what I remember. Since I am not very good at this forum, how about if you post rather than message me on the board, because I don't know how to do that?

From what I remember, soldering extensions onto the polyswitches is fine, and maybe desirable since they are solid wirer and subject to vibration. little multi wire extension leads would allow vibration without fatiguing the leadwirers. You probably got the PC mount version of the polyswitch instead of the leaded version. No big deal.

The long coil of wire that come with the prop is to limit current flowwhen the motor is stopped waiting for the breaker to blow. Losing an inch or even a foot of the 10 or 20 feet won't make any real difference. I do not even thing the coil of wire is necessary once using the polyswitches, but I figure the least you mess with the original it is easier to go back to original if you want to.

Chris

Chris

Thanks for the reply.

I was considering using "piggy back" crimp on spade connectors so it would be easy to experiment with different rated poly switches.

Do you have any idea why the threaded pitch adjusting rod broke immediately after installing with the rubber washers in place and unmodified wire length?

Herman

[ChrisBolkan 130]

Chris

Thanks for the reply.

I was considering using "piggy back" crimp on spade connectors so it would be easy to experiment with different rated poly switches.

Do you have any idea why the threaded pitch adjusting rod broke immediately after installing with the rubber washers in place and unmodified wire length?

Herman

Hi Herman, I'm not sure what you mean. Do you mean the jack screw broke? It shouldn't have. If you are using the circuit breaker IVO supplies and the coil of wire they supply, there is nothig the polyswitches can do to cause anything to break. Still I'm not sure I understand what you are asking.

Chris

[herman pahls 9]

Chris

I just noticed that you replyed to my question 8 days ago.Sorry.

Yes the jack screw broke within minutes of installing and everything was wired exactly as IVO sent the switch and breaker.

I should be getting the repaired IFA motor and jack screw back any day.

Today I started to wire in the poly switches and noticed that your switch wiring diagram differs from how IVO sends the prewired switch

as to where on the switch the power and ground and slipring connections are.

IVO sent the switch with power from the breaker and ground going to the middle pair of terminals of the 6 terminal switch.

You have the slipring wires to the motor originating from the middle pair.

I am trying to figure out why I had a jack screw failure so soon.

Hopefully the polyswitches will offer better protection and faster reset than the IVO breaker.

Do you have a Lycoming powered Magnum?

Does it have an IVO IFA prop that you developed the polyswitches on?

Thanks Herman

[SuberAvid 617]

Chris

I just noticed that you replyed to my question 8 days ago.Sorry.

Yes the jack screw broke within minutes of installing and everything was wired exactly as IVO sent the switch and breaker.

I should be getting the repaired IFA motor and jack screw back any day.

Today I started to wire in the poly switches and noticed that your switch wiring diagram differs from how IVO sends the prewired switch

as to where on the switch the power and ground and slipring connections are.

IVO sent the switch with power from the breaker and ground going to the middle pair of terminals of the 6 terminal switch.

You have the slipring wires to the motor originating from the middle pair.

I am trying to figure out why I had a jack screw failure so soon.

Hopefully the polyswitches will offer better protection and faster reset than the IVO breaker.

Do you have a Lycoming powered Magnum?

Does it have an IVO IFA prop that you developed the polyswitches on?

Thanks Herman

Hi Herman,

I am still working on my IVO set up and have not completed the mount for the brushes yet so I haven't run it yet. I am a bit concerned that you had a jack screw failure. I am hoping that was just an odd fluke. Fortunately I don't think it is catastrophic as long as you still are pitched where you have some climb capability if there is a failure in flight. One thing I was not clear on from the instructions was if the plastic washers are to be placed on the spool side of the shaft or the backing plate side with the spacer washers on the oposite. It seems like it would not matter since the plastic washer should provide a cushion on either side.

I was able to wire up my prop adjustment control to the unused extra buttons on my stick so I have the trim, prop and PTT all on the stick. I prewired it all on a plate I had in a blank instrument hole so I have the circuit breaker and the two LED lights for the fine and course pitch limits mounted through the plate and on the shelf behind it I mounted two relays and the poly switches. The dual relay switches and wiring circuit take the place of the manual switch supplied by IVO to change the polarity to the prop brushes. It's pretty cool having it all controlled on the stick.

[herman pahls 9]

Randy

Where do you get a stick grip with so many switch options?

IVO repaired the motor jack screw at no charge and I will re install tommorrow.

The jack screw failure happened without the poly switches installed.

I feel the poly switches will reduce the load on the mechanism.

What amperage of poly switch are you using?

Can you post how you are wiring them with your stick controled switch and relays?

Thanks Herman