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Experiments in hope of extreme power...
Page 1 of 1
Experiments in hope of extreme power...
Hi Guys,
Some of you know that I have been using a Shuriken engine to power my 1/2A profile protospeed model. The Shuriken is a quite old, out of production engine that has not been made or supported for many years now. I figured that until I broke it, it was still useful to play around with. I accidentally acquired aluminum and a ceramic coated cylinder liners in an Ebay acquisition of (mostly no good) parts.
The originally designed cylinder/liner assembly started out being made from Iron (piston) & steel ( cyl. liner). I don't know if many of these were made, but I have one.
Although it's WAY better than it's TeeDee rival, with a wrist pin rather than a ball-socket joint, it was not at all optimal for the time.
The next step was to go to a much lighter aluminum piston and run it in a chromed brass cylinder. Known as ABC. The next advance was to run an aluminum piston in a chromed Aluminum liner, that if nothing else yielded a lighter engine. Known as AAC (and boy the sturdy Shuriken is relatively heavy). The final stage of design yielded a Ceramic coated aluminum liner using an aluminum piston. This was known as AAO. Ceramic feels kind of slick, not quite that of teflon. Teflon coated pistons and parts have been used successfully in high performance model engines, but were not ever featured on any 1/2A production engine (other than Norvel) that I'm aware of. Engine modifiers generally sent out parts to a shop for coating, which would then require a re-fit in order to get them back into the engine. If fitted incorrectly, they worked poorly. I never came across published data on this coating procedure, so those that tried these things were truly pioneers, going out on a limb & often ruining parts and engines...
Nonetheless, in the quest for the holy grail of speed, failures are often expected along the journey. If not expected, they'll happen anyways!
I personally never tried the Iron/Steel combo because I knew the ABC was superior. That being said there was a great variance in the performance of my ABC piston/cylinder units. The reason being is that several cylinders had different porting (my parts were experiments by somebody). But, more importantly the fit and profile of the cylinders were different. With the tolerances in the tenth of a thou. (or less) I didn't have the instruments (+ knowledge of use) to do consistent measurements.
So I reverted to the tried and true "cut and try" method. Essentially meaning run the combo's & see what works best. In the end, I had my friend from California & master modeller John McCollum custom build me a few (one off) ABC piston / cylinder sets. Because John KNOWS the proper tapers + used a superior German Mahle ( high silicon alloy) aluminum for his pistons, his sets turned out to be the very best performers, even with MUCH less radical porting. The difference between best & worst being about 4,000 RPM!! ( 29,000 -> 33,000). It's hard to call a 29,000 RPM .049 a failure, but it really is when compared to a 33,000+ RPM engine. The inflight difference being ~ 20 MPH!!
At the end of the bench testing day, the promising Ceramic cylinder was a failure ( at 31,000 RPM), but it could very well be because the critical "fit" is off, not necessarily because of the Ceramic itself. Or maybe it is the Ceramic...?? I don't really know much anything other than what my trusty tach tells me. There are other maddening issues like bad / semi-failed bearings that have interfered with what might have been a superior result. Sadly, with no spares or spares with quality...my research is stopped for the time being. BTW, DO NOT tell me to use Boca Bearings, because that's a route to very bad results....ask me how I know?
I'll add photos later when I return from an appointment...
Cheer,
Paul
Some of you know that I have been using a Shuriken engine to power my 1/2A profile protospeed model. The Shuriken is a quite old, out of production engine that has not been made or supported for many years now. I figured that until I broke it, it was still useful to play around with. I accidentally acquired aluminum and a ceramic coated cylinder liners in an Ebay acquisition of (mostly no good) parts.
The originally designed cylinder/liner assembly started out being made from Iron (piston) & steel ( cyl. liner). I don't know if many of these were made, but I have one.
Although it's WAY better than it's TeeDee rival, with a wrist pin rather than a ball-socket joint, it was not at all optimal for the time.
The next step was to go to a much lighter aluminum piston and run it in a chromed brass cylinder. Known as ABC. The next advance was to run an aluminum piston in a chromed Aluminum liner, that if nothing else yielded a lighter engine. Known as AAC (and boy the sturdy Shuriken is relatively heavy). The final stage of design yielded a Ceramic coated aluminum liner using an aluminum piston. This was known as AAO. Ceramic feels kind of slick, not quite that of teflon. Teflon coated pistons and parts have been used successfully in high performance model engines, but were not ever featured on any 1/2A production engine (other than Norvel) that I'm aware of. Engine modifiers generally sent out parts to a shop for coating, which would then require a re-fit in order to get them back into the engine. If fitted incorrectly, they worked poorly. I never came across published data on this coating procedure, so those that tried these things were truly pioneers, going out on a limb & often ruining parts and engines...
Nonetheless, in the quest for the holy grail of speed, failures are often expected along the journey. If not expected, they'll happen anyways!
I personally never tried the Iron/Steel combo because I knew the ABC was superior. That being said there was a great variance in the performance of my ABC piston/cylinder units. The reason being is that several cylinders had different porting (my parts were experiments by somebody). But, more importantly the fit and profile of the cylinders were different. With the tolerances in the tenth of a thou. (or less) I didn't have the instruments (+ knowledge of use) to do consistent measurements.
So I reverted to the tried and true "cut and try" method. Essentially meaning run the combo's & see what works best. In the end, I had my friend from California & master modeller John McCollum custom build me a few (one off) ABC piston / cylinder sets. Because John KNOWS the proper tapers + used a superior German Mahle ( high silicon alloy) aluminum for his pistons, his sets turned out to be the very best performers, even with MUCH less radical porting. The difference between best & worst being about 4,000 RPM!! ( 29,000 -> 33,000). It's hard to call a 29,000 RPM .049 a failure, but it really is when compared to a 33,000+ RPM engine. The inflight difference being ~ 20 MPH!!
At the end of the bench testing day, the promising Ceramic cylinder was a failure ( at 31,000 RPM), but it could very well be because the critical "fit" is off, not necessarily because of the Ceramic itself. Or maybe it is the Ceramic...?? I don't really know much anything other than what my trusty tach tells me. There are other maddening issues like bad / semi-failed bearings that have interfered with what might have been a superior result. Sadly, with no spares or spares with quality...my research is stopped for the time being. BTW, DO NOT tell me to use Boca Bearings, because that's a route to very bad results....ask me how I know?
I'll add photos later when I return from an appointment...
Cheer,
Paul
Last edited by Paulgibeault on Wed Jun 27, 2018 2:27 pm; edited 4 times in total (Reason for editing : Grammar)
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
Re: Experiments in hope of extreme power...
Paul I hope they have your medical issues sorted out.... I follow your musing on Flying lines
I often wonder in your testing how much credence you give to various fuels more to the point the oils
I often wonder in your testing how much credence you give to various fuels more to the point the oils
fredvon4- Top Poster
-
Posts : 4010
Join date : 2011-08-26
Age : 69
Location : Lampasas Texas
Re: Experiments in hope of extreme power...
What prop used for the tests?
Here is my Picco with a Profi .8cc tuned pipe for reference:
Published on Feb 25, 2017
Custom Crank / Picco .0519 ci / .85 cc / APC 4.2x4 / 29,473 rpm
Custom crank for improved longevity and performance.
165 deg exhaust over stock @ 160 / 4oz break in time results:
Static: 12 oz thrust / 111.3 mph / .227 hp / 170 W
Brief peak needle 30,564 rpm
Static: 13.4 oz thrust / 116 mph / .255 hp / 190.2W
34W improvement over stock crank. Thank you Mel!
165 deg timing / 9in MRP
30% nitro / 20% oil / AP .09 carb / Profi .8cc Tuned Pipe
My CS RC with a Profi pipe (bit loaded down) it's the flight prop not so good
for bench testing really needs the 4.2x4 for that.
Published on Nov 24, 2017
CS .061 / Nelson Plug Med. / Profi .8cc Tuned Pipe / APC 4.5x4
Best Peak 25,193 rpm / .188hp / 140.3w / 12oz thrust / 96 mph
Hold peak 25,052 rpm / 25% nitro / 20% oil blend
8.75" Mean Reflective Point / "center of piston to 2" from end of stinger.
Needle Valve 3.75 turns out due to no pressure taps.
105.7g as shown with pipe
Here is my Picco with a Profi .8cc tuned pipe for reference:
Published on Feb 25, 2017
Custom Crank / Picco .0519 ci / .85 cc / APC 4.2x4 / 29,473 rpm
Custom crank for improved longevity and performance.
165 deg exhaust over stock @ 160 / 4oz break in time results:
Static: 12 oz thrust / 111.3 mph / .227 hp / 170 W
Brief peak needle 30,564 rpm
Static: 13.4 oz thrust / 116 mph / .255 hp / 190.2W
34W improvement over stock crank. Thank you Mel!
165 deg timing / 9in MRP
30% nitro / 20% oil / AP .09 carb / Profi .8cc Tuned Pipe
My CS RC with a Profi pipe (bit loaded down) it's the flight prop not so good
for bench testing really needs the 4.2x4 for that.
Published on Nov 24, 2017
CS .061 / Nelson Plug Med. / Profi .8cc Tuned Pipe / APC 4.5x4
Best Peak 25,193 rpm / .188hp / 140.3w / 12oz thrust / 96 mph
Hold peak 25,052 rpm / 25% nitro / 20% oil blend
8.75" Mean Reflective Point / "center of piston to 2" from end of stinger.
Needle Valve 3.75 turns out due to no pressure taps.
105.7g as shown with pipe
1/2A Nut- Top Poster
- Posts : 3509
Join date : 2013-10-20
Age : 61
Location : Brad in Texas
Re: Experiments in hope of extreme power...
VERY interesting stuff Paul! Thanks for sharing your experience with us here.
Re: Experiments in hope of extreme power...
What size are the bearings that they are difficult to source? Developing piston and liner is a lot of work, and certainly many things need to be measured very accurately to prove a design. Did you make the AAO sets? It's truly amazing that you can see a 4kRPM difference between liners sets if the porting is otherwise the same. This represents 45% more power at 33k, vs 29k. Are people running Fora or similar?
gkamysz- Gold Member
- Posts : 407
Join date : 2018-02-22
Location : Chicagoland
Re: Experiments in hope of extreme power...
Wow. Kind of reminds me of a pack of crotch rockets at 2 AM on the Interstate that sometimes wake me up when there are no leaves on the trees and its warm enough for that crowd to get out for a little highway to hell ridin'.
Question about these demons:
If, say for example, a typical Black Widow will run 3.5 minutes on its 8ccs of 15% nitro fuel, about how long will one of these demons run on 8ccs of whatever it is they're burning?
Question about these demons:
If, say for example, a typical Black Widow will run 3.5 minutes on its 8ccs of 15% nitro fuel, about how long will one of these demons run on 8ccs of whatever it is they're burning?
ticomareado- Account Under Review
- Posts : 1089
Join date : 2013-10-03
Location : NC
Re: Experiments in hope of extreme power...
HI Fred, and thanks for the nice wishes, much appreciated!
In AMA 1/2A speed & 1/2A Profile Proto events, I give NO credence to the fuels because they are mandated 10% nitro, 20% oil (50% castor - 50% synthetic often Klotz), the rest is methanol. The fuel is always supplied by the contest management, case closed.
In the old days before the mandated fuel came into effect, THAT was a whole different story! People (including me) used extreme (72-78% nitro) no alcohol & sometimes turbine oil (Mobil Jet II) was blended in. THAT was very potent fuel & gave enormous power over the standard. It ate glow plugs. Fortunately, we haven't had to play "chemist" in C/L speed for many years now & I don't mind that part one single bit.
Cheers, Paul
p.s. My Shuriken was indeed designed to handle all the nitro you could possibly use in it...
In AMA 1/2A speed & 1/2A Profile Proto events, I give NO credence to the fuels because they are mandated 10% nitro, 20% oil (50% castor - 50% synthetic often Klotz), the rest is methanol. The fuel is always supplied by the contest management, case closed.
In the old days before the mandated fuel came into effect, THAT was a whole different story! People (including me) used extreme (72-78% nitro) no alcohol & sometimes turbine oil (Mobil Jet II) was blended in. THAT was very potent fuel & gave enormous power over the standard. It ate glow plugs. Fortunately, we haven't had to play "chemist" in C/L speed for many years now & I don't mind that part one single bit.
Cheers, Paul
p.s. My Shuriken was indeed designed to handle all the nitro you could possibly use in it...
fredvon4 wrote:Paul I hope they have your medical issues sorted out.... I follow your musing on Flying lines
I often wonder in your testing how much credence you give to various fuels more to the point the oils
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
Re: Experiments in hope of extreme power...
HI Brad,
My reference standard prop for AMA 1/2A Proto is the: APC 4.2D X 4P nylon. Far too small for Cox engines, but excellent for Protospeed & Class II mouse race.
This prop I believe is too big for a piped engine on the ground. Perhaps trimming the diameter somewhat or using the APC 4.2 X 2P is better for that purpose.
Thank you for posting your Picco stuff....very interesting. Do you use a Galbreath de-stroked Picco or do you leave it the normal .061 (1cc) size?? The 1cc
size certainly has more power hands down. That being said, so far only Jerry Rocha of Napa has been able to extract the power necessary from a Picco to exceed the normal 85 mph. Jerry's best is 111mph & I flew that model for him. Wowza! At 4.4 ounces it takes off like a rocket & is too fast for all but the most experienced pilots! What a blast it is flying for Jerry!
Cheers, Paul
My reference standard prop for AMA 1/2A Proto is the: APC 4.2D X 4P nylon. Far too small for Cox engines, but excellent for Protospeed & Class II mouse race.
This prop I believe is too big for a piped engine on the ground. Perhaps trimming the diameter somewhat or using the APC 4.2 X 2P is better for that purpose.
Thank you for posting your Picco stuff....very interesting. Do you use a Galbreath de-stroked Picco or do you leave it the normal .061 (1cc) size?? The 1cc
size certainly has more power hands down. That being said, so far only Jerry Rocha of Napa has been able to extract the power necessary from a Picco to exceed the normal 85 mph. Jerry's best is 111mph & I flew that model for him. Wowza! At 4.4 ounces it takes off like a rocket & is too fast for all but the most experienced pilots! What a blast it is flying for Jerry!
Cheers, Paul
1/2A Nut wrote:What prop used for the tests?
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
Re: Experiments in hope of extreme power...
Paul it would be a treat to see some vid of that action!
The engine is stock all but the crank / known to be brittle and snap in short order.
Not a Galbreath de-stroked Picco, Mel made two for me aka "Toad" on RCG / RCU.
The stock engine is .0519 ci / .85 cc.
Here is the Picco in action hits 50K ish on the bench prior to launch:
Published on Nov 22, 2016
Picco P-Zero .05 / .85cc engine 2nd Vid - Cut Octura to 1426 detongued
Static rpm on the bench hit tad over 50,000 rpm.
RPM higher than the stock X427 prop, best pass 36,902 rpm
Med lift prop. 30% nitro / 20% castor. Best pass 43 mph.
I cut down the dia. and backcut on the blades of APC props for the TD .05
so far this is the best results getting brief peak down wind passes by the cam.
NANO III / 9oz / 28" span / APC 4.22x5.5
Best pass 26,647 rpm / 139 mph prop speed
Static 20,370 rpm / 1oz fuel / 25% nitro / 20 castor
With speed, the sound follows behind the plane neat effect.
Checked all passes found the best per posted vid:
Per Audio RPM Gauge 26,647
Per Prop Calc 139 mph
Per Doppler Wav. Scope software 136 mph / 219 Kp/h
Another surprising engine was the Fuji .05 shown here:
Published on Jul 24, 2016
Best pass 36,747 rpm gives a theoretical prop pitch speed of 157mph potential from a HQ carbon / nylon 4x4.5 prop
per audio tach from brief bursts of rpm past camera. With the right size plane the prop speed can be used to it's full advantage.
Per Doppler wave analysis: 238 kmh / 147.89 mph best pass.
Down wind shallow dives gets the rpm / speed up, prop is too small into the wind or when pushed
in steady banking turns. Peak speed in front of the cam is brief average speeds much lower.
Wing is approx 130sq. in. meant for a TD .09 this was just a way to test the engine out
and observe plane is too big for the engine.
The engine is stock all but the crank / known to be brittle and snap in short order.
Not a Galbreath de-stroked Picco, Mel made two for me aka "Toad" on RCG / RCU.
The stock engine is .0519 ci / .85 cc.
Here is the Picco in action hits 50K ish on the bench prior to launch:
Published on Nov 22, 2016
Picco P-Zero .05 / .85cc engine 2nd Vid - Cut Octura to 1426 detongued
Static rpm on the bench hit tad over 50,000 rpm.
RPM higher than the stock X427 prop, best pass 36,902 rpm
Med lift prop. 30% nitro / 20% castor. Best pass 43 mph.
I cut down the dia. and backcut on the blades of APC props for the TD .05
so far this is the best results getting brief peak down wind passes by the cam.
NANO III / 9oz / 28" span / APC 4.22x5.5
Best pass 26,647 rpm / 139 mph prop speed
Static 20,370 rpm / 1oz fuel / 25% nitro / 20 castor
With speed, the sound follows behind the plane neat effect.
Checked all passes found the best per posted vid:
Per Audio RPM Gauge 26,647
Per Prop Calc 139 mph
Per Doppler Wav. Scope software 136 mph / 219 Kp/h
Another surprising engine was the Fuji .05 shown here:
Published on Jul 24, 2016
Best pass 36,747 rpm gives a theoretical prop pitch speed of 157mph potential from a HQ carbon / nylon 4x4.5 prop
per audio tach from brief bursts of rpm past camera. With the right size plane the prop speed can be used to it's full advantage.
Per Doppler wave analysis: 238 kmh / 147.89 mph best pass.
Down wind shallow dives gets the rpm / speed up, prop is too small into the wind or when pushed
in steady banking turns. Peak speed in front of the cam is brief average speeds much lower.
Wing is approx 130sq. in. meant for a TD .09 this was just a way to test the engine out
and observe plane is too big for the engine.
1/2A Nut- Top Poster
- Posts : 3509
Join date : 2013-10-20
Age : 61
Location : Brad in Texas
Re: Experiments in hope of extreme power...
Ti,
If you can get 3.5 minutes from a Black Widow you truly have one economical engine! With 25% nitro & stock vents 90 secs to 2:30 (flight time) is about the best I see with the stock .082 tank venturi. True, the small Silver Bee / Golden Bee ?? .062" venturi tanks can give slightly over 3 minutes of run time. I can't answer your question about exactly how long (time wise) my engines run. My range is from 90 seconds to 2:10 sec. on the test stand with engine sideways (pick up at bottom).
What I do know is my flight testing showed that the LAP RANGE on my mouse racer INCREASED the more nitro I added. So if I had an engine that was a bit short on range (say 32-34 laps) with 40% nitro, going to 65% nitro increased the range to 36-40 laps at a faster speed.
Cheers, Paul
If you can get 3.5 minutes from a Black Widow you truly have one economical engine! With 25% nitro & stock vents 90 secs to 2:30 (flight time) is about the best I see with the stock .082 tank venturi. True, the small Silver Bee / Golden Bee ?? .062" venturi tanks can give slightly over 3 minutes of run time. I can't answer your question about exactly how long (time wise) my engines run. My range is from 90 seconds to 2:10 sec. on the test stand with engine sideways (pick up at bottom).
What I do know is my flight testing showed that the LAP RANGE on my mouse racer INCREASED the more nitro I added. So if I had an engine that was a bit short on range (say 32-34 laps) with 40% nitro, going to 65% nitro increased the range to 36-40 laps at a faster speed.
Cheers, Paul
ticomareado wrote:
Question about these demons:
If, say for example, a typical Black Widow will run 3.5 minutes on its 8ccs of 15% nitro fuel, about how long will one of these demons run on 8ccs of whatever it is they're burning?
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
Re: Experiments in hope of extreme power...
Sounds about right, IIRC, back in the late 1970's I was getting around that with my stock Golden Bee on standard 25% nitro fuel. This was on a Q-Tee flown single channel (elevator was fix wired through an adjustable RC clevis allowing trim adjustments for flight), 5.25x4 to 6x3 props and Ace RC exhaust sleeve throttle.Paulgibeault wrote:True, the small Silver Bee / Golden Bee ?? .062" venturi tanks can give slightly over 3 minutes of run time.
GallopingGhostler- Top Poster
-
Posts : 5671
Join date : 2013-07-13
Age : 70
Location : Clovis NM or NFL KC Chiefs
In search of Extreme power...
Here are some photos that show the "evolution" of piston / cylinder technology experiments. It was most lucky that the piston from my best ABC assembly just happened to fit well (or as well as I think it should) right into the ceramic cyl liner. Sadly it was several thousand rpm short of best...even though if you see the photos, the cermanic liner cutouts are radical, and go completely through the cylinder as per original design. My custom ABC liners are not radically cut that way, because it's impossible to control cylinder roundness with a cylinder cut that way. I think roundness + correct taper in a cylinder, trumps porting every time...So far, that holds true.
Also of note is the late Chuck Schuette designed head with was designed to take the excellent Novarossi tapered seat glow plugs. It works well, but is just short of the one piece Norvel Spiralite speed plug, which although does not last very long (1 per flight), still gives the highest performance so far... This is acceptable for C/L speed, but lousy for most other applications.
Note: That pink tubing is actually bladder tubing that I use for my tests as my engine is pressure fed.
Also of note is the late Chuck Schuette designed head with was designed to take the excellent Novarossi tapered seat glow plugs. It works well, but is just short of the one piece Norvel Spiralite speed plug, which although does not last very long (1 per flight), still gives the highest performance so far... This is acceptable for C/L speed, but lousy for most other applications.
Note: That pink tubing is actually bladder tubing that I use for my tests as my engine is pressure fed.
Last edited by Paulgibeault on Mon Jun 04, 2018 3:27 pm; edited 5 times in total (Reason for editing : add'i info added)
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
In search of Speed
gkamysz wrote:What size are the bearings that they are difficult to source? Developing piston and liner is a lot of work, and certainly many things need to be measured very accurately to prove a design. Did you make the AAO sets? It's truly amazing that you can see a 4kRPM difference between liners sets if the porting is otherwise the same. This represents 45% more power at 33k, vs 29k. Are people running Fora or similar?
HI gkamysz,
I was MOST DISAPPOINTED to notice that my previous detailed reply sometime back somehow got lost in cyberspace & never did show up. I find sometimes that happens and I have no idea why...?
So I'll try again. The bearings I am trying to obtain are:
Rear bearing: .312" I.D. X .500" O.D.
Front bearing: .187" I.D. X .375" O.D.
The best original bearings seemed to have nylon ball separators. These are standard US sizes I think. I do not know what the internal clearance is, but I think it equates to a C-3 or possibly C-4.
The Boca R1810-ZZ 110207 C (rear) and SR166-ZZ #3 110207 C (front) replacements are a performance failure. (I believe their internal clearance is too tight for this application).
NO, I did not make the AAO cylinder. It came in an assorted bunch of parts acquired on Ebay, (I think from the auction sale of the company?)
One thing in my testing is that the porting was not the same. If anything the ceramic coated cylinder had larger & deeper ports. I would not have thought that that could be a negative, as my fastest brass (chromed) cylinders are mildly ported by comparison. However, there are many questions unanswered as to the accuracy of the AAO cylinder's internal profile dimensions. My measuring equipment does not have the accuracy needed, nor do I have the knowledge to make the changes required if they are not right. In fact, I don't really even know what RIGHT is supposed to be for these little motors. I do however know what accurate bench tach readings translate to in air performance.
I have not yet seen a Fora used in 1/2A proto. Cyclon's & Profi 1/2A combat engines have been used & work OK, but can't seem to fly over 90 mph, with ~ 85 mph being more common. They do however SOUND FABULOUS in the RPM range on the ground, but just don't seem to go fast, for some reason. ( Jerry Rocha's testing of the Cyclon found that although it turns up equally fast on the ground with the same prop, it does not unload in the air, like his other engines do) I have not spoken to the users to see what kind of prop they are using. My conjecture (& it's only conjecture) is that they have the RPM, but no torque to turn the necessary 4" of pitch required to go fast.
Regarding a 4,000 RPM difference. YES, you have not lived until you've seen the enormous power people such as Jerry Rocha from Napa can pull out of a given engine without radical modification. Jerry just makes sure the fits are "right" corrects any obvious errors & his engines are awesome, compared to the rest of the field (even at the AMA Nats). It also helps that Jerry builds a lighter/straighter model than anyone else! ( That's " FREE " speed right there).
Given my RPM at 33,000 is similar to Jerry's, I feel my building must improve to reach my magic milestone of 100 MPH which only 2-3 people in North America are capable of achieving. That would have easily won the AMA Nats last year (because Jerry wasn't there). Of course with my current bad bearings situation, progress has come to a stop for the time being. I'm hoping to talk to a Swiss watchmaker friend in Europe this summer to see if something there can be sourced...we'll see.
Cheers, Paul
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
Re: Experiments in hope of extreme power...
I have been using the Boca replacements in my engine for 2 seasons. I'm also using lighter pitched props. I use the APC 4.6x3 and the Russian yellow or blue. I keep the nitro at 35%-40%. Baldwin told me that I should be considering a minimum of 50%. To date, my bearings are holding up. I just don't think the originals can be sourced as Fred mentioned that they were custom in themselves. I've been in search of the stock spraybar which he told me to use the Cox 128. Well it's a smaller diameter and the length is also considerably shorter not allowing enough of the fuel barb protruding out the other side. He told me to send him a few $$$ and he would dig the stuff out. I passed on it. My buddy has bent his ear numerous times over the past 2 years for the spraybar. I really don't want to drill the case so my other option is to make a sleeve and try another.
Ken Cook- Top Poster
- Posts : 5623
Join date : 2012-03-27
Location : pennsylvania
Re: Experiments in hope of extreme power...
I did note that there's smaller and more balls in the stock vs the Boca units
Ken Cook- Top Poster
- Posts : 5623
Join date : 2012-03-27
Location : pennsylvania
Re: Experiments in hope of extreme power...
The guys that used to run nitro dragster R/C here said that there was someone on the mainland that would hand assemble bearings matching the inner and outer races to the ball size, going through many bearings to come up with the proper fit. Bearings are made by the thousands and then sorted according to what the tolerances end up. I think that would be the designating number like ABEC -5, ABEC-7 etc. Maybe someone on this forum knows of this person that blueprints bearings.
PS The nitro dragster guys normally run 60 percent and up nitro in their fuel
PS The nitro dragster guys normally run 60 percent and up nitro in their fuel
coxaddict- Gold Member
- Posts : 429
Join date : 2013-01-27
Location : north shore oahu, Hawaii
Re: Experiments in hope of extreme power...
That person I believe was the late Greg Settles from Colorado. Greg rebuilt my rear bearing for me saying it was the smallest bearing he had ever worked on!
Although Greg's re-build ran excellent, it was not long lived as it failed later on after a number of high speed runs. It was funny how Greg called me up on the phone & then ran up the motor. "Sound good enough for you Paul?" he said. Sounded great over the phone...! Greg did however build bearings that set AMA national speed records in the hands of Jerry Rocha (of Napa, CA) and others. Greg also built bearings for certain Novarossi car engines & dragster engines as well.
Sadly, Greg passed away from cancer last year and us performance modellers dearly miss him.
If however this person is not Greg Settles, then I would like to get in contact with him...
Cheers, Paul
Although Greg's re-build ran excellent, it was not long lived as it failed later on after a number of high speed runs. It was funny how Greg called me up on the phone & then ran up the motor. "Sound good enough for you Paul?" he said. Sounded great over the phone...! Greg did however build bearings that set AMA national speed records in the hands of Jerry Rocha (of Napa, CA) and others. Greg also built bearings for certain Novarossi car engines & dragster engines as well.
Sadly, Greg passed away from cancer last year and us performance modellers dearly miss him.
If however this person is not Greg Settles, then I would like to get in contact with him...
Cheers, Paul
coxaddict wrote:The guys that used to run nitro dragster R/C here said that there was someone on the mainland that would hand assemble bearings matching the inner and outer races to the ball size, going through many bearings to come up with the proper fit. Bearings are made by the thousands and then sorted according to what the tolerances end up. I think that would be the designating number like ABEC -5, ABEC-7 etc. Maybe someone on this forum knows of this person that blueprints bearings.
PS The nitro dragster guys normally run 60 percent and up nitro in their fuel
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
Re: Experiments in hope of extreme power...
I finally found the long lost photos hiding in my computer!
Top photo shows the four evolutions of the Shuriken cylinder materials.
Lf. to Rt. : Iron piston/ steel cylinder. Chromed brass cylinder/ alum. piston. Chromed alum. cylinder using alum piston.
Ceramic coated Alum. cylinder with alum piston. All engines use a steel rod and wrist pin.
Those with Shuriken engines will know that the cylinder ports are completely milled out leaving a cylinder with "finger" looking ports.
Such a cylinder likely has to be fully finished inside before the ports are cut away. If the ports are cut away first then the finishing hone
will have a hard time staying centered. This can produce an out of round cylinder which is very counterproductive to high performance.
Piston longevity may be less on the finger ported cylinders as well, but I've no hard supporting data on that. I do know on Carl Dodges FAI speed
2.5cc engine with similar fingered cylinder ports, his pistons sometimes only lasted for as little as one run! A blazing fast run, but only 1 run
between piston replacements. Carl made his own engine & parts so replacement pistons were plentiful...
My highest revving chromed brass cylinders to date do not have the "finger ports" rather the cylinder is thinned as much as is dared in
making the ports, but the wall remains intact all the way to the bottom. Looks much less 'radical', but my tach does not lie...
Note: The homemade head shown was designed & built by the late Chuck Schutte. Chuck came up with a head shape that worked easily
as well as anything at the time. It uses Novarossi taped seat glow plugs. One strong advantage is that, Novarossi plugs come in 6 or 7
different heat ranges, from Hot to Cold. This is VERY useful to a tuner to be able to easily change plugs to accommodate different atmospheres
as well as different fuels, without having to resort to head re-shimming.
p.s. The N.G on the brass cylinder with the "hat shaped section" exhaust port stands for no good. Nice try but no cigar...!
Top photo shows the four evolutions of the Shuriken cylinder materials.
Lf. to Rt. : Iron piston/ steel cylinder. Chromed brass cylinder/ alum. piston. Chromed alum. cylinder using alum piston.
Ceramic coated Alum. cylinder with alum piston. All engines use a steel rod and wrist pin.
Those with Shuriken engines will know that the cylinder ports are completely milled out leaving a cylinder with "finger" looking ports.
Such a cylinder likely has to be fully finished inside before the ports are cut away. If the ports are cut away first then the finishing hone
will have a hard time staying centered. This can produce an out of round cylinder which is very counterproductive to high performance.
Piston longevity may be less on the finger ported cylinders as well, but I've no hard supporting data on that. I do know on Carl Dodges FAI speed
2.5cc engine with similar fingered cylinder ports, his pistons sometimes only lasted for as little as one run! A blazing fast run, but only 1 run
between piston replacements. Carl made his own engine & parts so replacement pistons were plentiful...
My highest revving chromed brass cylinders to date do not have the "finger ports" rather the cylinder is thinned as much as is dared in
making the ports, but the wall remains intact all the way to the bottom. Looks much less 'radical', but my tach does not lie...
Note: The homemade head shown was designed & built by the late Chuck Schutte. Chuck came up with a head shape that worked easily
as well as anything at the time. It uses Novarossi taped seat glow plugs. One strong advantage is that, Novarossi plugs come in 6 or 7
different heat ranges, from Hot to Cold. This is VERY useful to a tuner to be able to easily change plugs to accommodate different atmospheres
as well as different fuels, without having to resort to head re-shimming.
p.s. The N.G on the brass cylinder with the "hat shaped section" exhaust port stands for no good. Nice try but no cigar...!
Paulgibeault- Gold Member
- Posts : 259
Join date : 2011-09-24
Location : Leduc, Alberta Canada
Re: Experiments in hope of extreme power...
Sounds like that was Greg. Most of the engines used for the dragsters were Nova Rossi. Sad to hear of his passing.
coxaddict- Gold Member
- Posts : 429
Join date : 2013-01-27
Location : north shore oahu, Hawaii
Re: Experiments in hope of extreme power...
Running vid of mine no mods.
First gen engine # 118 / 1991 Shuriken .05
VY 4.49 x 3.15 glass combat prop
Per 2017 prop calc: 32,380 rpm / .37hp
30oz thrust / 272w / 97 mph pitch speed
Needle valve around 3.5 turns out, very thirsty.
Engine is new with only 3 tanks of fuel.
15cc tank shown / 20% castor / 35% fresh nitro.
Brief run as the noise was outrageous! Won
this one on ebay $669.46 shipped. This is the only
YouTube vid of a running vintage Shuriken to date.
We are very lucky to have a great place to share vids!
Original owner bought it late 1990 from the maker
for $215. Took BV time to assemble, shipped early 1991
First gen engine # 118 / 1991 Shuriken .05
VY 4.49 x 3.15 glass combat prop
Per 2017 prop calc: 32,380 rpm / .37hp
30oz thrust / 272w / 97 mph pitch speed
Needle valve around 3.5 turns out, very thirsty.
Engine is new with only 3 tanks of fuel.
15cc tank shown / 20% castor / 35% fresh nitro.
Brief run as the noise was outrageous! Won
this one on ebay $669.46 shipped. This is the only
YouTube vid of a running vintage Shuriken to date.
We are very lucky to have a great place to share vids!
Original owner bought it late 1990 from the maker
for $215. Took BV time to assemble, shipped early 1991
1/2A Nut- Top Poster
- Posts : 3509
Join date : 2013-10-20
Age : 61
Location : Brad in Texas
Re: Experiments in hope of extreme power...
I know Larry Driskill had one at the NATS in the 90's. I don't believe he was present at the time and the engine was in the hands of Mike Wilcox. Roy Glenn another combat pilot was present and during one of my runs last year Roy told me to reduce my prop size. I was using the APC 4.6x3. My engine might also be the engine Larry had. I came across a post where they removed the anodizing on the case for the glow clip in which mine is identical. I do enjoy running mine. I ended up changing out the bearings as my originals were SHOT!! I ended up with the BOCA replacements. I did tach mine when I first received it but I don't recall the rpm's.
I know Fred Baldwin suggested using 70% nitro. I also have 3 styles of Glo Bees . If memory serves me correct, I was getting the best performance from the sport version plug vs the racing. It would be great to have a Nelson plug for this.
I know Fred Baldwin suggested using 70% nitro. I also have 3 styles of Glo Bees . If memory serves me correct, I was getting the best performance from the sport version plug vs the racing. It would be great to have a Nelson plug for this.
Ken Cook- Top Poster
- Posts : 5623
Join date : 2012-03-27
Location : pennsylvania
Re: Experiments in hope of extreme power...
Good to hear the glo bees work with these engines, have not found various temp inserts.
I have some GB that came with the adapters for the cox / NV / AP / VA engines. AP and
NV inserts will they work too?
Yes read high nitro is needed timing is low at 150 so the nitro is
for temp control of the liner to piston fit in the air was mentioned.
I have seen what appears to be a bored out stock adapter for the Nelson plug.
My engine came with no anodizing on the top, opened up the back end and top
to clean and oil - was mint inside.
The 4.6x3 is a good choice out of the APC line up. The VY prop will likely hit as RC 39k
The lower mass APC prop should bust 40k rpm with RC. Would rather fly with them
than break glass props considering protecting the stock bearings.
I have some GB that came with the adapters for the cox / NV / AP / VA engines. AP and
NV inserts will they work too?
Yes read high nitro is needed timing is low at 150 so the nitro is
for temp control of the liner to piston fit in the air was mentioned.
I have seen what appears to be a bored out stock adapter for the Nelson plug.
My engine came with no anodizing on the top, opened up the back end and top
to clean and oil - was mint inside.
The 4.6x3 is a good choice out of the APC line up. The VY prop will likely hit as RC 39k
The lower mass APC prop should bust 40k rpm with RC. Would rather fly with them
than break glass props considering protecting the stock bearings.
1/2A Nut- Top Poster
- Posts : 3509
Join date : 2013-10-20
Age : 61
Location : Brad in Texas
Re: Experiments in hope of extreme power...
I see looking at your video your head clamp ring is mill finish. All of mine are black anodized, looks cool but totally impractical. As for the Norvel and other head buttons. The Glo Bee is smaller in diameter, therefore you could possibly open up the head clamp on the Shuriken to accept the other head buttons. You do run the possibility of breaking into the holes of the clamp where the head wrench pins go. Without measuring, I don't know for certain how much larger a AP, Merlin, etc. head button is. What I will say is that the AP utilized a decent plug design that always yielded performance numbers that were very satisfactory. The lifespan however was a bit short.
I really need to pull out my runner and experiment more with it. The Cyclon and Fora make things so easy that I stick with them as they run all day long on 10% nitro without issue. The Shuriken needs a bit more attention. Your correct in regards to the noise as it does have a note unlike most others.
I really need to pull out my runner and experiment more with it. The Cyclon and Fora make things so easy that I stick with them as they run all day long on 10% nitro without issue. The Shuriken needs a bit more attention. Your correct in regards to the noise as it does have a note unlike most others.
Ken Cook- Top Poster
- Posts : 5623
Join date : 2012-03-27
Location : pennsylvania
Re: Experiments in hope of extreme power...
Yes I admit it i like its an interesting engine but is the price justified? I don't know maybe one day I'll try to build a similar one for me But building a complete engine is harder than making a single cylinder But to obtain such an engine speed .... i does not know if I could arrive at such result its a cool looking engine
davidll1984- Diamond Member
- Posts : 2327
Join date : 2020-02-12
Age : 39
Location : shawinigan
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