small holes drilled in prop

[Don Ferrette]

Rodney were just asking questions here anything else is imagined. Dan simply shared his experience with props. What you speak of with MS is an issue between he and I and has zero to do with this thread. Andy Brown likewise has zero to do with this thread or my source of information. If we need to open a seperate thread on pitch gauges feel free to do so but the issue between Mark Sholund and I is best left between Mark Sholund and I. I would have asked the same question of any other prop man that threw this guage in the mix. Its absolutely un-personal and the AB thing is imagined. Ive only talked to Andy through email corresondence in months in reference to purchased propellers - not that its anyones business.I will leave up to others to explain how the pitch guage made it on this thread and why???? :huh: I just figured since it went there lets talk about them....... Please pm me this kinda stuff coz it really has no place here and is a perfect way to kill a good thread where I an others are looking for answers.

thanks,

Hugh

- On Andy Brown - Andy Brown is a pioneer,teacher, and mentor of rc boats. He has perfected many props(abc h & s) and boats before some of us were born and likely while we jabber here is doing more of the same. When it comes to him comparison is stupid and ill advised. He is a "one of a kind" propeller guy whos stats speak for themselves.Andy is a well respected rc boater in my book. No matter what differences he may have had with this or that one when it comes to rc boats the man is the tops... and likely a Hall of Famer. He is also one willing to still learn and that in my opinion is his strongest asset -

with that said lets let it go coz theres nothing to argue unless you can find 10 people to disagree which I doubt you can. Enuf about Andy Brown, guys ears gotta be on fire by now dang.

FYI record books show there are other people that do not sell propellers that do excellent prop work. Kenny Stone,Terry Kelly,Don "Hackmaster" Ferette,Doug Smock, just to mention a few. Lets stay away from the prop guy competition and learn about the various pitch gauges strenghts and weaknesses.If thats what were gonna do.

I saw the gauge Keven just sold on IW. This is the type you speak of? Tell me what are its strenghts and weaknesses if there are any????? Were going to need a pitch gauge thread. Im not the only one here that has never used one. Im just not ashamed to admit it...... <_<

Hugh

Hugh,

Just read this for first time. Interesting reading. Note, Don ferrette is not the Hackmaster. He doesn't do props at all. He hates working on props. The Hackmaster is Steve Sutton. Just wanted to get that one straight.

I also just read this 1st time and yes I definitely do not like working on props. Swimming in wood chips, metal shavings and paint fumes are more my style, just ask Finch. Steve "Hackmaster" Sutton (now retired from prop work) helped me lay down some nasty numbers with the props he worked up for me. B)

 

[hugh hargett]

Thank you for correcting me Mr Finch. Next question how do you get in touch with Steve lol. Does he do work for the masses?

Hugh

 

[hugh hargett]

Rodney were just asking questions here anything else is imagined. Dan simply shared his experience with props. What you speak of with MS is an issue between he and I and has zero to do with this thread. Andy Brown likewise has zero to do with this thread or my source of information. If we need to open a seperate thread on pitch gauges feel free to do so but the issue between Mark Sholund and I is best left between Mark Sholund and I. I would have asked the same question of any other prop man that threw this guage in the mix. Its absolutely un-personal and the AB thing is imagined. Ive only talked to Andy through email corresondence in months in reference to purchased propellers - not that its anyones business.I will leave up to others to explain how the pitch guage made it on this thread and why???? :huh: I just figured since it went there lets talk about them....... Please pm me this kinda stuff coz it really has no place here and is a perfect way to kill a good thread where I an others are looking for answers.

thanks,

Hugh

- On Andy Brown - Andy Brown is a pioneer,teacher, and mentor of rc boats. He has perfected many props(abc h & s) and boats before some of us were born and likely while we jabber here is doing more of the same. When it comes to him comparison is stupid and ill advised. He is a "one of a kind" propeller guy whos stats speak for themselves.Andy is a well respected rc boater in my book. No matter what differences he may have had with this or that one when it comes to rc boats the man is the tops... and likely a Hall of Famer. He is also one willing to still learn and that in my opinion is his strongest asset -

with that said lets let it go coz theres nothing to argue unless you can find 10 people to disagree which I doubt you can. Enuf about Andy Brown, guys ears gotta be on fire by now dang.

FYI record books show there are other people that do not sell propellers that do excellent prop work. Kenny Stone,Terry Kelly,Don "Hackmaster" Ferette,Doug Smock, just to mention a few. Lets stay away from the prop guy competition and learn about the various pitch gauges strenghts and weaknesses.If thats what were gonna do.

I saw the gauge Keven just sold on IW. This is the type you speak of? Tell me what are its strenghts and weaknesses if there are any????? Were going to need a pitch gauge thread. Im not the only one here that has never used one. Im just not ashamed to admit it...... <_<

Hugh

Hugh,

Just read this for first time. Interesting reading. Note, Don ferrette is not the Hackmaster. He doesn't do props at all. He hates working on props. The Hackmaster is Steve Sutton. Just wanted to get that one straight.

I also just read this 1st time and yes I definitely do not like working on props. Swimming in wood chips, metal shavings and paint fumes are more my style, just ask Finch. Steve "Hackmaster" Sutton (now retired from prop work) helped me lay down some nasty numbers with the props he worked up for me. B)

See thats what I get from listening to someone who didnt know. I was told by a mutual pal that you were hackmaster guess they were wrong. Back to Terrys question what s the answer? I think based on Andys scenario the answer would be no. Yay or Nay?

Hugh

 

[John Finch]

The Hackmaster is retired. Got to be too much work and not enough fun. Many of us have been there done that when our hobbies have turned into a business. Then the hobbie goes away! Then what do you do to get away from it all....golf? No can do. Like the fast stuff! Good prop stuff here!

John

 

[dwilfong]

Andy, Jim, John, anyone. Here are the numbers I came up with when measuring LE pitch as David described a couple pages back. If any of you guys can confirm numbers or let me know if they are close or correct that would be awesome.

These are numbers from 3 props that I have here that I just pulled from my prop box.

ABC 1914 - 2.375 LE pitch

ABC 1816 - 2.74 LE pitch

Octura 1450 - 2.59 LE pitch

Just curious if these are even close to the advertised or actual??? Thanks in advance!!!

Rod, measuring at 50% radius with an Orlic gauge, 5 degrees, I get one blade of my 1816 as 2.66 LE pitch, the other blade 3.02. My 1450 has 2.59 LE pitch on one blade, 2.66 on the other, I checked two 1450's and they were the same. I don't have a 1914.

So at 30k rpm that give you approx 80mph for the 1816 (2.84 ave) and 74 mph for the 1450 (2.625 ave) at 0 slip

That's right on, but you will still find yourself using the Slip/fudge factor because you are not using the true leading edge pitch number.

Try putting you prop on the gage upside down and see what kind of L.E. pitch you find. Different huh?

When you find the True L.E. pitch and you adjust the progression to match the drag of the hull, you will find ZERO slip at the L.E. and XX,XXX RPM times X.XX" L.E. pitch equates to the exact speed your boat is running.

OK so you teased us with the back side scenario.

I have always spent more time on the back side than the front.

SOOOO give up a little more please.

David

 

[hugh hargett]

Well Terry im not sure if thats what Andy meant but I think his scenario means that slip isnt the same at different rpm levels. Hopefully he will clear it up coz the answer and the scenario dont work together if you look at how the question was worded.Assuming that water and air agitation is considered slip in his scenario.

 

[hugh hargett]

The Hackmaster is retired. Got to be too much work and not enough fun. Many of us have been there done that when our hobbies have turned into a business. Then the hobbie goes away! Then what do you do to get away from it all....golf? No can do. Like the fast stuff! Good prop stuff here!

John

well if you guys would just give me the props it wouldnt be business would it? So you could still enjoy the hobby and do a good deed for the day ^_^ . Who would have ever know than Dan posting holes in his props for me would have turned into such a lengthy informative thread.Anyway ....

later

Hugh

 

[John Beardslee]

The Hackmaster is retired. Got to be too much work and not enough fun. Many of us have been there done that when our hobbies have turned into a business. Then the hobbie goes away! Then what do you do to get away from it all....golf? No can do. Like the fast stuff! Good prop stuff here!

John

Hi John,

Glad to see a good number of us "Old Dogs" still kicking!!!! I've shared my experience of a hobby that turned into work and then messed up my "Hobby" Yup, no addiction like adrenlin!!!!!! You don't have to be in it to get the rush and I've walked away from ever crash since playing with toys!

John

 

[John Finch]

John,

A blast from the past! Still kicking. That is great! That's about all we can ask for now. The alternative isn't so good. Good to hear from you.

 

[John Finch]

The Hackmaster is retired. Got to be too much work and not enough fun. Many of us have been there done that when our hobbies have turned into a business. Then the hobbie goes away! Then what do you do to get away from it all....golf? No can do. Like the fast stuff! Good prop stuff here!

John

well if you guys would just give me the props it wouldnt be business would it? So you could still enjoy the hobby and do a good deed for the day ^_^ . Who would have ever know than Dan posting holes in his props for me would have turned into such a lengthy informative thread.Anyway ....

later

Hugh

Hugh,

That is how Steve got overwhelmed. He started just working on props for our little group that travels together for record trials. He saw some good results on some props and then started playing with the numbers. Being a technical guy, he started getting into props much deeper than I ever did and he was having fun with how the numbers worked out. Before long we all saw our speeds climbing and we were having a great time at the record trial events together. After a couple of years he was tweaking props for all the guys at the pond and it was more work than fun. He just gave it up this Spring. All the good prop guys have been mentioned here, so give one of them a call.

 

[Andy Brown]

Andy, Terrys question suggest that the slip stays constant your scenario suggest otherwise so is the answer to his question yes or no? Yes means that yes slip is the same at different rpm. I thought the same as you did with the lower rpm scenario but that would make the answer to his question "NO" slip is not the same at different rpm ranges right?

Hugh

Ahhh you are right Hugh, I read the question wrong. "No" would be the answer to Terry's question.

 

[Mike Rappold]

Andy, Jim, John, anyone. Here are the numbers I came up with when measuring LE pitch as David described a couple pages back. If any of you guys can confirm numbers or let me know if they are close or correct that would be awesome.

These are numbers from 3 props that I have here that I just pulled from my prop box.

ABC 1914 - 2.375 LE pitch

ABC 1816 - 2.74 LE pitch

Octura 1450 - 2.59 LE pitch

Just curious if these are even close to the advertised or actual??? Thanks in advance!!!

Rod, measuring at 50% radius with an Orlic gauge, 5 degrees, I get one blade of my 1816 as 2.66 LE pitch, the other blade 3.02. My 1450 has 2.59 LE pitch on one blade, 2.66 on the other, I checked two 1450's and they were the same. I don't have a 1914.

So at 30k rpm that give you approx 80mph for the 1816 (2.84 ave) and 74 mph for the 1450 (2.625 ave) at 0 slip

That's right on, but you will still find yourself using the Slip/fudge factor because you are not using the true leading edge pitch number.

Try putting you prop on the gage upside down and see what kind of L.E. pitch you find. Different huh?

When you find the True L.E. pitch and you adjust the progression to match the drag of the hull, you will find ZERO slip at the L.E. and XX,XXX RPM times X.XX" L.E. pitch equates to the exact speed your boat is running.

Andy,

i understand the part about measuring the leading edge pitch on the "front side' of the propeller. It will be less than the back side and thus more of the limiting factor or govenor. Can you further explain the comment about adjusting the pitch progression to match the drag of the hull?

Mike

 

[Andy Brown]

Andy, Jim, John, anyone. Here are the numbers I came up with when measuring LE pitch as David described a couple pages back. If any of you guys can confirm numbers or let me know if they are close or correct that would be awesome.

These are numbers from 3 props that I have here that I just pulled from my prop box.

ABC 1914 - 2.375 LE pitch

ABC 1816 - 2.74 LE pitch

Octura 1450 - 2.59 LE pitch

Just curious if these are even close to the advertised or actual??? Thanks in advance!!!

Rod, measuring at 50% radius with an Orlic gauge, 5 degrees, I get one blade of my 1816 as 2.66 LE pitch, the other blade 3.02. My 1450 has 2.59 LE pitch on one blade, 2.66 on the other, I checked two 1450's and they were the same. I don't have a 1914.

So at 30k rpm that give you approx 80mph for the 1816 (2.84 ave) and 74 mph for the 1450 (2.625 ave) at 0 slip

That's right on, but you will still find yourself using the Slip/fudge factor because you are not using the true leading edge pitch number.

Try putting you prop on the gage upside down and see what kind of L.E. pitch you find. Different huh?

When you find the True L.E. pitch and you adjust the progression to match the drag of the hull, you will find ZERO slip at the L.E. and XX,XXX RPM times X.XX" L.E. pitch equates to the exact speed your boat is running.

Andy,

i understand the part about measuring the leading edge pitch on the "front side' of the propeller. It will be less than the back side and thus more of the limiting factor or govenor. Can you further explain the comment about adjusting the pitch progression to match the drag of the hull?

Mike

Mike, click this link. http://www.intlwater...eedmaster&st=30

You will find a discussion from two years ago. About three pages into it you will begin to find posts I made concerning progression.

I will say that there is no perfect amount of progression for all conditions in the same boat. You could add more progression to the Top Fuel boat and it will load up the motor better along with getting quicker acceleration out of the hole, but your top end speed would suffer and you would probably hurt the motor going through the traps. Too little progression and your 60 foot times would suffer, but you'd go faster on the top end.

Anyway, that's pretty basic out comes. You will find details in the other thread. I will have to dig out the prop mapping that you sent me from the Top Fuel prop. I don't remember much about it.

 

[hugh hargett]

The Hackmaster is retired. Got to be too much work and not enough fun. Many of us have been there done that when our hobbies have turned into a business. Then the hobbie goes away! Then what do you do to get away from it all....golf? No can do. Like the fast stuff! Good prop stuff here!

John

well if you guys would just give me the props it wouldnt be business would it? So you could still enjoy the hobby and do a good deed for the day ^_^ . Who would have ever know than Dan posting holes in his props for me would have turned into such a lengthy informative thread.Anyway ....

later

Hugh

Hugh,

That is how Steve got overwhelmed. He started just working on props for our little group that travels together for record trials. He saw some good results on some props and then started playing with the numbers. Being a technical guy, he started getting into props much deeper than I ever did and he was having fun with how the numbers worked out. Before long we all saw our speeds climbing and we were having a great time at the record trial events together. After a couple of years he was tweaking props for all the guys at the pond and it was more work than fun. He just gave it up this Spring. All the good prop guys have been mentioned here, so give one of them a call.

I know what you mean. I was always curious about Dons scale props for obvious reasons - many records! :mellow: and scales are my first love . I have 3 new blades by Andy two by John Beardslee and two from Eric Canto that I havent even been able to try yet . I already know they are all going to perform well. Just a hunch I have -_- .

 

[John Finch]

The Hackmaster is retired. Got to be too much work and not enough fun. Many of us have been there done that when our hobbies have turned into a business. Then the hobbie goes away! Then what do you do to get away from it all....golf? No can do. Like the fast stuff! Good prop stuff here!

John

well if you guys would just give me the props it wouldnt be business would it? So you could still enjoy the hobby and do a good deed for the day ^_^ . Who would have ever know than Dan posting holes in his props for me would have turned into such a lengthy informative thread.Anyway ....

later

Hugh

Hugh,

That is how Steve got overwhelmed. He started just working on props for our little group that travels together for record trials. He saw some good results on some props and then started playing with the numbers. Being a technical guy, he started getting into props much deeper than I ever did and he was having fun with how the numbers worked out. Before long we all saw our speeds climbing and we were having a great time at the record trial events together. After a couple of years he was tweaking props for all the guys at the pond and it was more work than fun. He just gave it up this Spring. All the good prop guys have been mentioned here, so give one of them a call.

I know what you mean. I was always curious about Dons scale props for obvious reasons - many records! :mellow: and scales are my first love . I have 3 new blades by Andy two by John Beardslee and two from Eric Canto that I havent even been able to try yet . I already know they are all going to perform well. Just a hunch I have -_- .

Good thing about the electric setup is you can pretty much do the rpm and pitch calculations and get the expected results because of the tremendous instant horsepower of the electric setup. The motor specs seem to follow the ratings very well. Your hunch is correct.

 

[hugh hargett]

About progression . With the parabolic type shape I asked Jim based on all his real time data and measured numbers on the props did he think an optimum helical function and pitch could be derived we decided it was doubtful as he hadnt made any observations that pointed to that. I still think in outerspace somewhere there could be based on "E" or "Pi" the foci points of parabolic shapes or something. It seems similar in a cup/decup situation that you are somehow aiming how the water comes off the blade like changing the foci as you change the parabolic shape. I have zero formal knowledge of hydro dynamics so its just a thought thats probably wrong.It just seems intuitive to me.Does it matter if you did find one? probably not coz everything changes from boat to boat.People like to play with their struts and all to get the boat running a certain way so its gonna be different down the board.This is the one thing that made me understand Rod G. saying follow the JAE format of no adjustabilty - allowing you to just work on finding a good prop with the angle set at zero degrees. Make alot of sense if you want a boat thats quickly tunable, and want to know what the prop is doing to the boats attitude. The CNC and cad renderings would be the best way to get a great prop and know exactly whats going on with it.I sure hope Andy someday gets that going again with a hard material prop. People talked about the price of the process of doing the hard material cnc props but im sorry Id pay 100.00 or maybe more for a prop like that. Guess Im different about the persuit of speed coz im certainly not rich.

the only "optimum" that seems to be floating around is and aspect ratio of 1.4-1.6 with respect to efficiency . I dont know how this was derived????? anyone?

 

[dwilfong]

As far as progression in the prop what seams to be the best place to have it?

the props I have had the best results with have little or no progression till you get to the last 10deg.

All the progression is at the trailing edge cup.

I have bin using the lead in progression to tune the boat speed I want.

I have also bin tapering the trailing edge to a point and removing the flat.

This has removed some of the lift in the prop and made it easer to pull higher pitch.

On my hydro it makes it easer to tune the ride as the strut changes do not get as critical.

I know I do things ass back wards. But it works for me.

 

[hugh hargett]

David from what ive leaned you dont want to remove the flat from the trailing edge . I think you may think its working coz in effect youre likely back cutting and adding te rake angle which will do what you say but tapering the trailing edge introduces drag off the blades te. When its flat and sharp its acting like a thin wedge rudder. No proof just my understanding of these many prop threads, and articles on props. I play around with props alot coz in FE were still trying to find out what works and we can make more rpm just by adding some voltage. In nitro you have to get the right pipe and internal combo for more rpm so faster is harder for you. From some fe programs ive run it seems the vcut series of propellers will let you turn more rpms on an outrigger while keeping pitch the same as say an x if were talkin stock cuts. I do believe that zero strut angle produces the least amount of underwater drag with respect to the strut. That is truly just an opinion, coz I could see a few arguments especially when talking surface piercing, that suggest otherwise. I thought Andy said he started adding progression gradually at the halfway point.

 

[dwilfong]

Remember the blade is a supper caveatting hydrofoil. when you remove the flat on the back it will change the way it lifts.

It still needs to be sharp.

My buddy Dave has a few patents on hydro foils and spent lots of time with his son professional water skiing.

He mad many skeges for the skis. He is the one that turn me on to it.