NAMC Mig-35B motor mount modification

Hi Everyone -

I have experimented with moving the motor around on several park jets over the years to help with better balance and performance in my planes.  I wrote this article awhile back about some of my thoughts and experiences at that time about motor location in a prop and slot park jet.

I also recently shot this video as part of my intermediate park jet video series.

In this article, I will cover how I go about moving the motor mount forward in the Mig-35B, I have done this a few times now, primarily to account for the extra weight of keeping the paper on the Dollar Tree foam in the rear part of the plane.  The Mig-35B is a bit more tricky than a lot of park jets to move the motor forward, but hopefully you will get the idea if you want to experiment with other planes.  Also, I will hopefully demonstrate how I modify the prop slot and other aspects of the plane to accommodate a smaller, shorter quad motor which I use pretty much exclusively in my park jets now with some excellent results.

So some of the modifications that need to be made to this or any other park jet are a function of just moving the motor forward and some are a function of using the shorter quad motor.  In this write up I will try to identify which is which depending on what motor you want to put in your park jet.  You might want to do it all so that if you want to experiment later with a shorter quad motor, your jet is all ready to go😎

I should also mention at this point that the plans I am using for all these measurements in this article are for a plane that will be built at 95% of scale, so I will end up with a 25.5"/648mm wingspan.  Depending on the size you build your Mig-35B or any other park jet, your measurements will more than likely be different.

On most previous Mig-35B builds where I have moved the motor forward, even those not made of DTF, I has moved the motor forward by about 1".  For most of the DTF planes, I found this was not quite enough to really tighten things up the way that I like them, so I am going to experiment with moving the motor and servos forward a bit more😉

One of the first things you want to is identify where the trailing edge of your KF airfoil is going to be.  Even if you are not going to use them, this area is probably a good limit to set for moving the motor forward.  You can move the motor too far forward and then the plane can have almost "gyroscopic torque roll" which can make launching a real challenge.  I simply trace a line where the trailing edge of the KF will be so that I know the maximum I can move the prop slot forward which needs to be modified for using a shorter quad motor. 

I normally start off making all the measurements and mods to the wing plate so I know where things can go, this has a domino affect on other parts of the plane, so I do everything in pencil.  I have marked many of the lines in highlighter simply for this article so that they might be easier to see.

In the picture below I have marked the trailing edge of my KF and also moved the leading edge of the prop slot forward so that it will only be about 5 mm deep to allow best clearance for the quad motor.  Now I know how much room I have to play with for moving my motor forward.  In this picture, I have currently moved the prop slot leading edge forward about 14 mm which is how far I would move it forward if I was using a quad motor in this park jet.

I find using clear plastic rulers is easiest for this type of work as I can see through it to help measure from existing lines to the new lines.  This ruler happens to be metric, so I make all measurements in mm.  I have about 35 mm with which to play here after marking the leading edge of the prop slot (this is without moving the motor just yet, but since I will be moving the prop slot forward also, this is key to ensuring I don't move things too far forward).

In order to give myself a little "leeway", I decided to go with 30 mm for the motor mount.  I know that I have already moved my prop slot forward by 14 mm to accommodate the shorter quad motor, so that will factor in when I look at moving servos and other air frame parts forward.  So as you can see in the picture below, I essentially move everything to do with the motor mount forward by 30 mm.

Also, there are two slots which will accept tabs from the bottom part of the fuselage when it is "mated" to the wing plate, so those also need to be moved forward 30 mm as well.  These are affected by the new motor mount placement, but not the new prop slot placement.

Since the leading edge of the prop slot will be moving forward 44 mm from original position, I move the rudder servo slot forward that amount also.  Moving the servos forward also helps shift some weight forward to keep things tighter around the CG.  This will also affect the aileron and elevon servo locations which we will move later when we get to that part.

On the Mig-35B and many other park jets for that matter, when you move the motor mount forward, it will affect a wing spar, so you will want to remeasure this to see what size the new wing spar will be.  I like to leave at least 1 cm or maybe a little bit more between the end of the spar in this location and the leading edge of the wing as I will be angling/trimming the wing leading edge back after the KF airfoils are installed.

Now it is time to move on to adjusting the fuselage, this is a bit tricky, but taking your time and ensuring you measure everything correctly will pay off later in the build.  In the centre part of the fuselage, I move this forward 30 mm as it is affected by moving the motor forward, but not the leading edge of the prop slot.

I then adjust the slot which will slide onto the wing plate and move that forward by 30 mm also.

This is one area where it gets a little tricky, normally the area where it says "cut out and save" would still be attached as part of the fuselage if built stock, however now it is not after moving some lines for the modification.  I cut this out and save it as it is critical to support the bottom of the fuselage after "mating" it to the wing plate.

Next, it is time to adjust the top parts of the fuselage that will be on the top of the wing plate after "mating" the fuselage and wing plate.  These are primarily affected by moving the leading edge of the prop slot forward to accept a shorter quad racing motor, so 44 mm is the key measurement here. 

This also affects the tab and slot to align the electronics bay door.  I measured it to 30 mm, you can measure to whatever size you want.  In the picture immediately below, I measured the "slot" on the side piece of the fuselage to accept the tab from the electronics bay door.

Here I moved the back of the electronics bay door forward by 44 mm to accept the new leading edge of the prop slot. 

Then I adjusted the tab to 30 mm to fit into the slot on the side of the fuselage. 

Since I moved the leading edge of the motor mount forward so much, I also added some to the back plate/trailing edge of the motor mount to maintain some structure.  I like to keep my prop slots a little larger to allow for best airflow to and from the prop, so I split the difference between 30 and 44 mm and moved the trailing edge of the prop slot forward by 37 mm.

Next, time to move on to the nacelles which need to be shortened for both the motor mount mod and the quad motor in this situation.  First I normally move the servos forward as shown in the pictures below.  Since I have already moved the rudder servo slot forward 44 mm in the wing plate, I do the same for the aileron and elevon servos.

You will note below that moving the aileron servo forward interferes with a tab that goes into the wing plate, so I simply measured off 15 mm in this situation, remembering to carry this over to the tab on the wing plate as you can see in the second picture.

In these following pictures, I modified the inside part of the nacelle so that the tab is moved forward to fit into the slot I moved forward by 30 mm when moving the motor mount forward.

Then I moved the trailing edge of the nacelle forward by 44 mm to allow for the fact the leading edge of the prop slot is also moved forward by 44 mm.  This is something to check after the motor is installed by turning the motor by hand with the prop installed first to ensure it does not contact anything before giving it power and chopping up your plane😮

One last thing to check is to remove a bit from the top of the motor mount (I start with about 5 mm and then adjust as needed).  If the top of the motor mount is left the way it is, the electronics bay door won't lay flush.

Hopefully this has been somewhat helpful.  Moving the motor forward on the Mig-35B is a little trickier than with some other park jets, but I have done it on three Mig-35Bs thus far and it has worked out well.  I have moved the motor forward on several different park jets, the principles are basically the same, just remember it can create a bit of a "domino affect", so always best to figure things out and double check before cutting out the foam.

#ParkJetnoise

#ParkJetpilot

Cheers,

Scott

Quad motors in park jets - summary after over a year of testing - 13 Sep 2018

Hi Everyone -

This summary has been a long time coming and if you already follow this blog and my You Tube channel, much of what you are about to read or watch has already been covered.  However, I wanted to do a bit of a wrap up to review some of the more important points and some of the items I may not have discussed to this point.😊

I have certainly become a convert to using quad motors in my single motor, prop in slot park jets.  Their light weight and incredible power certainly fits the way I like to fly.  Of course this power does come with a cost in both money and amp draw and requires some consideration about which plane to choose and how to build it, but for me it has been worth it.

Here is a video I shot that this blog supports.

I mentioned three major sources of information that I found very helpful making the correct choices to achieve the power setups I was looking for.  Here they are.

• rcplanepirate's You Tube channel;
• EngineerX's You Tube channel; and
• miniquadtestbench.com. 

You can also find all the my bench test data on my motor test spreadsheet.  Each motor I tested has it's own page, so if you scroll along the bottom you can navigate to whatever motor you want to view.  Also on this spread sheet is test data from the 2212/6 2200 kv and 2212/5T 2700 kv motors which are the two most popular park jet motors around and what I replaced in all my planes.  I put this data there for info and to compare.  Also, rather than providing links to every motor, prop, ESC and battery I used in testing in this blog post, you will find links to all of these on the motor test spreadsheet.  Where applicable, I also put what custom settings I selected on certain ESCs to maximize performance.  All these setups have been thoroughly tested at the field also.

I also started a thread on the RC Powers forum which may also cover some items missed in this blog post or videos.

From the first post of the RC Powers forum thread, here are the advantages and disadvantages of using quad motors over the more conventional 2212 motors in 2200 and 2700 kv.

Advantages

• quad racing motors tend to be much lighter, saving anywhere from 15-25 grams just in motor weight alone;
• paired with the right prop and ESC, they can produce equal to or often far more power than the standard 2212 2200 kv or 2212/5T 2700 kv motors, so very high thrust to motor weight ratios;
• with so much time and effort being put into the development of lighter, more powerful quad racing motors all the time, the performance is increasing in leaps and bounds whereas the 2212 2200 kv motors other than perhaps becoming cheaper, have not changed much in the last several years from a standpoint of weight and power output;
• although quad motors are often more expensive, because there are so many different companies making them, the competition is fierce and you can often find them for a very reasonable price. For example, I have only paid full price on about 25% of the motors I have purchased in the last year, the rest were all picked up on sale (although one could say I might have gone broke saving money😏);
• many quad motors are designed to be run on batteries from 2-6S, so a wide choice of battery options;
• if you find a motor you really like, they are often sold in bunches of four at a more reasonable price.

Disadvantages

• due to their smaller physical size, they often might not have the torque of a 2212 2200 kv motor. Even though the test bench numbers might show incredible performance, sometimes because they are about half the physical size of a 2212 size motor, they just don't have the "muscle" to push a larger, "draggier" plane around or deal with windier conditions. Therefore airplane size and weight becomes very critical. I have found that planes with about 27" wingspan or less and under about 21 oz AUW work the best, as always, the lighter the better;
• when you build your "prop in slot" plane, you do need to adjust the front of the prop slot quite a bit to compensate for the much shorter "bell/can", otherwise the prop will run far too close to the leading edge of the prop slot causing a lot of noise and causing the prop to run much less effectively/efficiently;
• with a couple of exceptions, I have found that motors with a stator size of 2306 or better (2406, 2307, 2207, 2208 for example) and greater than 2600 kv seem to give the best power when looking for equal or better power than produced by the 2212 2200 kv motor setups;
• they are often considerably more expensive than 2212 2200 kv motors which can often be found on Ebay for $5 USD, but there are some fairly reasonable options available that are pretty peppy and much lighter than a 2212 2200 kv motor setup; and
• they are considerably more "amp hungry" than the 2212 2200 kv motor, normally requiring a 40A ESC on 3S whereas you can often run the 2212 2200 kv motor with a 30A ESC.

As mentioned in the first video, here are the final reviews I did organizing the motors into "budget", "middle of the pack" and "serious power where cost doesn't matter"😉

Budget/value

Middle of the pack (includes a couple of motors to avoid)

My top five choices where cost and efficiency isn't an issue😎

I have also created several playlists to organize other "table talks" about motors, ESCs, batteries that I tested during this process.  As time goes on and I have evaluated these components more thoroughly, these play lists will be updated.  Also is a playlist of all the flying tests at the field.

Thorough reviews of individual quad motors can be found here.  

ESC reviews can be found here.

Battery reviews can be found here.

Field testing play list can be found here. 

One thing I should mention that I did not mention in the video, if you don't want to spend money on new ESCs, experiment with higher timing and different PWM settings if you can.  Even if you don't have a thrust stand to evaluate, normally the quad motors I tested all seemed to like a pretty high timing setting for max performance.  Having said that, monitor the heat build up carefully in your ESC as often most ESCs will run warmer with a higher timing setting.

So certainly none of this information is exhaustive and I will continue to evaluate and learn as my park jet journey continues.  I may still test the odd motor that comes along but for now I am pretty satisfied with the setups I have discovered and will continue to use quad motors in my park jets for the foreseeable future😊

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

Initial impressions and bench testing of the Brother Hobby EngineerX 2307 2700 kv motor

Hi Everyone -

I recently completed a bench test session of another quad racing motor I picked up to evaluate, the BrotherHobby EngineerX 2307 2700 kv that I picked up from Banggood.  I picked mine up for $23.99 USD, I notice the regular price from Banggood is $30.67, although at the time of writing this blog post it is on sale for the same price I paid.

I discovered this motor watching EngineerX's YouTube channel, here is his test video of this motor before it was released to the public.

I was very pleased to be able to exchange a few words with him about this new motor.  He mentioned that it might not be for all out speed, but perhaps very good torque.  If you want more details about the "guts" of the motor, please watch his video as he takes it apart and shows the details of the motor.

Mine weighed 34 gr/1.2 oz out of the box, it comes with the standard bolts and a prop nut, the finish is very nice and it spins very smoothly.

With the prop and other hardware attached ready to go in the plane, it weighs 48 gr/1.7 oz which I think is very good for a 2307 motor, it is right there with all the 2306 size motors I have tested thus far.

I started off the bench testing with the 6x4 APC gas prop, you can read all the test numbers on the motor test spreadsheet which also has links to all the components used in the testing.  The thrust numbers were not that great, but the amps numbers were noticeably low, so I tested with the 6x4 KMP props and finally the Gemfan 6045 carbon nylon prop which is what I will field test it with initially on 3S.

Here are the test numbers for this motor on 3S using the GF 6045 prop and the Turnigy AE-45A ESC with custom settings of 22.5 degrees timing and 24 KHz PWM frequency.

50% throttle - 15.7A/192.3W producing 635 gr/22.4 oz of thrust;

100% throttle - 39.4A/451.3W producing 1200 gr/42.3 oz of thrust.

So I am excited to get to the field and test it, my experience has been that with the GF 6045 CN prop, the bench numbers normally carry over well to the field😊

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

Tattu R-Line 1550 4S 75C batteries initial impressions and testing

Hi Everyone -

I received a couple of Tattu R-Line 1550 4S 75C batteries in the mail a couple days ago to experiment with some serious speed in my park jets😀

These batteries have a very good reputation from what I have read and watched on YouTube, they were not cheap, but I only bought a couple for some experimentation and serious speed fun!

I went with this small size as I didn't want to pay a big weight penalty, so even though my flights will be short, they should be fast😉  The batteries weigh 186 gr/6.6 oz.  The normal 2200 3S batteries I use weigh 192 gr/6.8 oz, so my planes should still be pretty light to help them be fast. 

I already did some quick testing for a modified RC Powers Su-30 V4 I am building specifically for speed.  Here is a short video I shot discussing this testing.  You can watch more about this special build by going to this playlist on my YouTube channel.

As discussed in the video, the only successful test was with the EMAX RS2306 2750 kv motor using the 6x3 EMP prop and the HobbyWing Platinum PRO 40A ESC with custom settings of 26.25 degrees timing and 8 KHz PWM frequency.  You can see the full details on my motor test spreadsheet, but here are the numbers for the combo I mentioned with this new Tattu 4S battery.

50% throttle - 21.8A/346.5W producing 940 gr/33.2 oz of thrust;

100% throttle - 54.8A/860.2W producing 1630 gr/57.5 oz of thrust.

WOW!  That is a 45% increase in thrust over the best mid range power on 3S and 36% increase at full throttle!😲

Until my 5" props that I have ordered show up, this is the setup I will experiment with.

Here are the 5" props I have ordered based on watching rcplanepirate's video on his testing of the EMAX RS2306 2750 kv motor and his personal recommendations. I pasted this list in from the comments of this video.

Hobby King

HobbyKing 5040 GRP/nylon prop https://hobbyking.com/en_us/glass-fib... Dalprops "Indestructible" Bull Nose 5045 V2 https://hobbyking.com/en_us/dalprop-5... Diatone Bull Nose Plastic Propellers 5 x 4.5 https://hobbyking.com/en_us/diatone-b... Banggood DALPROP 5045 Bullnose PC Propeller https://www.banggood.com/2-Pairs-DALP... Gemfan 5045 5 Inch Propeller Bullnose https://www.banggood.com/4PCS-Bullnos... KINGKONG/LDARC 5040 Propellers https://www.banggood.com/10-Pairs-KIN...

So I am excited to get to the field and start experimenting with these new batteries and this setup in a plane, it is going to be scary fast!😳

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

Initial post flight report GepRC GR2306 2750 kv motor

Hi Everyone -

Just back from the field blasting 12 flights through my new GepRC GR2306 2750 Kv motor😀  You can read more about my initial impressions and bench testing of this motor at this blog post.

From what I saw today, this motor paired with the 6x3 EMP prop using the Turnigy AE-45A ESC with custom settings of 22.5 degrees on the timing and 24 KHz PWM frequency is the new "king" of the quad racing motors I have tested thus far in my park jets.👍

Here is some video of one of today's flights.  It definitely has much more power mid range, I had to be careful with how much I advanced the throttle when launching or it would want to rip it out of my hand!😲  Normally with most motor setups I launch at around 60% throttle, with this motor I had to back that off to about 50% throttle to feel like I could still hang on to the plane.

I also flew the EMAX RS2306 2750 kv motor with the 6x3 EMP prop today and overall, the GepRC has more mid range power and top end speed.  Not as noticeable an increase in top end speed, but definitely at mid range between about 50-75% throttle.  In fact, I would estimate I would be able to reduce the throws down a bit more the plane moves along so fast at mid range, just so I could keep up with the plane.😊

I pushed it hard for 12 flights and it ran smooth and strong the whole time, no hesitation no matter how hard I slammed the throttle around.  Although it was a cool day, temps got up to about 12 C/54 F, the motor and ESC ran very cool, barely any noticeable heat build up at all, so I think even in warmer weather, this setup would run just fine.

Very impressed with this motor and it's performance today, I may have to order another one to have a couple of serious speed setups😉

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

Initial impressions and bench testing of the GepRC GR2306 2750 kv motor

Hi Everyone -

I received this GepRC GR2306 2750 kv motor in the mail yesterday and managed to get some bench testing done today😀

As you can see above, it comes with one prop nut and two sets of M3 screws, one set 7mm long and the other 8mm long.  Without any hardware, the motor weighs 32 gr/1.1 oz.  The motor wires are 150mm/5.9" long.

It has a hollow shaft and fairly minimal metal on the top.  According to the Banggood write up in the link above, it is made with 7075 aluminum.  The shaft is hollow all the way through.

It has curved N52 grade magnets which are one of the best grades of magnets used in brushless motors, it has a nice cut out as you can see in the bottom for the wires to be protected.  It is a "naked bottom" motor with no full base plate as you find on a lot of motors.  The gap between the stator and the magnets is very tight and when the motor is spun by hand, it spins smoothly, but the magnets feel very strong.  The shaft is held on with a small hex bolt, however it does not come with a spare like some other motors I have tested.

The bolt pattern is 16x16 mm, so I will only be able to use two screws to hold the "X" mount to the motor, but I think that will be sufficient.

With the prop and all the other hardware needed to put in a park jet, the motor weighs 48 gr/1.7 oz.

I tested the motor with both the 6x4 APC gas prop and the 6x3 EMP prop with the Turnigy Plush, Turnigy AE-45A ESC and Hobby Wing Platinum PRO 40A ESCs.  You can read the complete details as well as find links to all the components on the motor test spreadsheet.  The numbers are all on 3S.  Again, this motor preferred the Turnigy AE-45A ESC with custom settings of 22.5 degrees timing and 24 KHz for both props.  According to the Banggood specs, this is a 45A motor.

Based on the numbers alone, I think this motor might push the EMAX RS2306 2750 Kv motor out of the top spot for motors I have tested thus far.  

Here are the best numbers for the GepRC GR2306 2750 kv motor with the 6x4 APC gas prop.

50% throttle - 19.9A/238.0W producing 685 gr/24.2 oz of thrust;

100% throttle - 45.0A/506.3 producing 1115 gr/39.3 oz of thrust.

These are the best numbers I have seen for any of the motors I have tested thus far with the 6x4 APC gas prop, although it is a bit amp hungry.  Based on experience, I would fly this motor with the 6x4 APC gas prop and the Turnigy AE-45A ESC, although it would be pushing the ESC especially hard.

Here are the best numbers for the GepRC GR2306 2750 kv motor with the 6x3 EMP prop and Turnigy AE-45A ESC.

50% throttle - 18.9A/225.8W producing 730 gr/25.7 oz of thrust;

100% throttle - 41.7A/478.2W producing 1290 gr/45.5 oz of thrust.

Wow😁😲  This is the first motor I have seen that produced over 700 gr of thrust at mid throttle, incredible!  I won't bother fooling around, the flight test will be with the 6x3 EMP prop and the Turnigy AE-45A ESC😉  Excited to get it out for a spin very soon😁

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

Bench test session with 2700 Kv plus motors and 6x3 EMP/TGS/KMP prop

Hi Everyone -

I recently completed a fairly significant test session going back through all the quad racing motors I have been testing that are 2700 Kv or higher and testing them with the 6x3 EMP prop.  If you click on this previous link, it will take you to the RC Timer site, these props are also available under different names TGS from Hobby King and KMP from Banggood.  I normally buy mine from RC Timer as although you have to buy them in bundles of five, they are much cheaper.

I had wanted to do this for awhile, and was finally pushed to get it done after recently bench and field testing the Hawksky AT2306 II 2750 kv motor.  You can read more about this motor, my initial impressions and bench testing at this blog post.  Here is some flight video I shot with this prop and motor.

Here is the list of 2700 and over Kv motors I tested on the bench recently.

• EMAX RS 2306 2750 Kv;
• Foxeer DATURA X2206 2700 Kv;
• BeeRotor Z2207 2780 Kv;
• Brother Hobby Returner R2 2205 2800 Kv;
• Racerstar BR2306S 2700 Kv; and
• SunnySky Edge R2305 2800 Kv. 

All of the motors except the Brother Hobby 2800 showed marked improvement in thrust while doing so more efficiently compared to the 6x4 APC gas prop.  The Brother Hobby motor performed worse with the 6x3 prop.  I suspect due to it's smaller size stator, it needs the 6x4 prop to really push the motor to better levels of performance.  You can read the full details of all the test numbers on the motor test spreadsheet.  

The EMAX RS2306 2750 Kv motor continues to be a very good performer and actually with this prop preferred the Turnigy AE-45A ESC with custom settings of 22.5 degrees and 24 KHz PWM frequency over the more expensive HobbyWing Platinum PRO 40A ESC that it preferred with the 6x4 APC gas prop.  All of these results are on 3S.  The EMAX motor still has the best 50% throttle performance although it did not increase significantly over the 6x4 APC gas prop.  It had a significant increase of 125 gr of thrust at full throttle with the 6x3 prop.

EMAX RS2306 2750 Kv motor with 6x3 EMP prop, Turnigy AE-45A ESC on 3S

50% throttle - 16.4A/197.5W producing 650 gr/22.9 oz of thrust;

100% throttle - 36.5A/416.3W producing 1200 gr/42.3 oz of thrust.

The pleasant surprise is the very inexpensive Racerstar BR2306S 2700 Kv motor.  It showed a 20 gr improvement in mid range thrust and 115 gr at full throttle.  I will keep an eye on it as it is pulling 37.1A at full throttle which might be a bit more than it is designed to handle, but anytime I see anything close to 1100 gr of thrust it makes me take notice😀

Racerstar BR2306S 2700 Kv motor with 6x3 EMP prop, Turnigy AE-45A ESC on 3S

50% throttle - 12.3A/153.8W producing 525 gr/18.5 oz of thrust;

100% throttle - 37.1A/459.8W producing 1080 gr/38.1 oz of thrust.

The real star of the show is the SunnySky Edge R2305 2800 kv motor showing a 50 gr increase in thrust at mid range and a whopping 185 gr increase in thrust at full throttle while drawing 5 less amps than it did with the 6x4 APC gas prop😲  It produces the most thrust at full throttle by 50 gr compared to the EMAX motor.

SunnySky Edge R2305 2800 Kv motor with 6x3 EMP prop, Turnigy AE-45A ESC on 3S

50% throttle - 14.2A/172.5W producing 615 gr/21.7 oz of thrust;

100% throttle - 40A/456.8W producing 1250 gr/44.1 oz of thrust.

So I am excited now to do some more field testing, first up will be the SunnySky Edge motor, it ripped with the 6x4 APC gas prop, so if the thrust is that much better with the 6x3 EMP, it should move along pretty smartly😉

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

Gemfan 6045 carbon nylon props initial impressions and testing

Hi Everyone -

I received a couple of packs of Gemfan 6045 carbon nylon props in the mail in the last couple days😀  I tested them today on the 2212/6 2200 kv, Racerstar BR2406 2600 kv and RC Timer FR2306 2650 kv motors.  If you want to skip straight to the test numbers, you can go to my motor test spreadsheet.

As these props were designed for quads, they come four to a pack, two of each rotation.  Lots of prop rings including ones that fit on most park jet motor shafts.  Not a bad deal for $3.79 USD.

The props are quite light, it was hard for my less than accurate kitchen scale to get a good result, but I'm sure they weigh about 4 gr each, the same as a 6x4 APC gas prop, so pretty light.  rcplanepirate has already tested some of these on the bench with very good results.  After watching his tests and having a couple discussions with him, I thought I would pick some up to help boost some more power out of the lower Kv (less than 2700) motors I am currently using.  I figured the little bit of extra pitch with a stiff prop should hopefully give more power at lower RPM and hopefully not drive the amp draw up too high.

Please check out RCPP's YouTube channel, tons of great test and educational info.😀

These props are very stiff, even stiffer than the 6x4 APC gas props, but I am a bit concerned they might be a bit brittle, or perhaps this was just one prop.  As I was trying to get a grip on one of the quad racing motors I tested today to tighten the prop nut, I must have pushed against the prop blade a bit too firmly and it broke cleanly almost right at the hub as you can see below.😒

I compared it's length to the 6x4 APC gas prop and it is 3/16" longer as you can see in this picture below.

There is also a bit more prop blade surface area as you can probably see in the picture above and below.

I know it might be hard to see in these following pictures, the blade thickness seems to be a bit thinner on the Gemfan prop and the pitch is not as aggressive at the hub compared to the 6x4 APC.

The prop blade also seems to have a bit more of a curve or "under camber"(?) compared to the 6x4 APC.  Due to the blade shape and it's stiffness, it is certainly as quiet as the 6x4 APC and again while difficult perhaps to see in this pictures, I can definitely see the increase in pitch down the length of the blade.

Test results discussion

The biggest improvement in power with this prop showed up in the 2212/6 2200 kv motor which is the most popular park jet motor around currently and the Racerstar BR2406 2600 kv.  There was a noticeable increase of mid range power with the RC Timer FR2306 2650 kv motor, but not a big increase in top end, although it did break 1000 gr of thrust on the bench with all three motors which always gets my attention😉  I will focus mostly on the 2212 2200  and Racerstar motors for the rest of the discussion.  I have found in field testing that the RC Timer motor doesn't quite have the torque to continue pushing good power to the top of the throttle range compared to the other two.

I tested all the motors with both the Turnigy Plush 40A and Turnigy AE-45A ESCs (links for these are on the spreadsheet linked in the first paragraph).  For the Plush, everything was left at factory default.  For the AE-45 I used different settings depending on the motor based on experience from my previous testing.  Below I am listing what I think would be the best setup for each motor.  Gens Ace 2200 3S 45C batteries were used for all the testing.

2212/6 2200 Kv motor

I found the mid range power to be best with the Plush ESC, not much difference (5 gr) at top end thrust, so I would probably choose the Plush unless I find another custom setting that would work best with the AE-45 and this motor/prop combo.

50% throttle - 11.9A/145.7W producing 540 gr/19 oz of thrust;

100% throttle - 32.3A/391.8W producing 1020 gr/36 oz of thrust.

Wow😲  The mid range thrust is about 60 gr more than the best I have seen with any other prop/ESC for about the same amp draw.  At full throttle, it is about 70 gr more than the previous best I have seen, with about 4 more amps drawn, but still under the 34A limit that these motors seem to have.  This is the first time I have seen more than 1000 gr of thrust out of this motor on a 2 blade prop!

Racerstar BR2406 2600 kv motor

I found that the Turnigy AE-45A ESC with custom settings of 22.5 degrees timing and 24 KHz on the PWM (pulse width modulation) frequency works best with this motor, so that is what I used.

50% throttle - 12.6A/154.2W producing 560 gr/19.8 oz of thrust;

100% throttle - 35.3A/426.1W producing 1070 gr/37.7 oz of thrust.

Again...WOW😲  Compared to the previous best results I have seen with this motor which is with this ESC with the settings listed above and the 6x4 APC gas prop, it is a 30 gr increase in mid range power for the same amp draw basically (.1A difference) and a 110 gr increase at full throttle for only 1.1 more amps drawn!  If this performance translates to the field with this inexpensive motor, it puts it right up there with the "big boy" quad racing motors I have tested thus far😀

I am very excited to test the GF 6045 prop on the Multistar Viking 2208 2600 kv motor which is the strongest of the sub 2700 kv motors I have tested thus far😉

Of course not to get too excited, but I have run the Racerstar BR2406 2600 kv motor and the Viking motor a lot, so I feel pretty sure they have the torque in the air to keep swinging this prop with authority throughout the throttle range.  But only one way to find out, strap it in a plane and get to the field.😀  I hope to get some initial field test results in the next week weather permitting.

Stay tuned for more bench and field testing with this prop😊

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

"Table Talk" - BeeRotor Z2207 2780 Kv motor review for use in park jets

Hi Everyone -

I just shot this video giving my thoughts and a review on the BeeRotor Z2207 2780 Kv motor from RC Timer😊

This motor when paired with the Turnigy AE-45A ESC with custom settings (22.5 degrees timing and 24 KHz PWM frequency) is one of the top performing quad racing motors using the 6x4 APC gas prop on 3S that I have tested thus far.  It is very close to the performance of the EMAX RS2306 2750 Kv motor that currently leads the pack of quad racing motors I have tested thus far.

You can read all the details of my bench testing with this BeeRotor and many other motors on my motor test spreadsheet.  Simply scroll along the bottom to find the motor that interests you.😊

Links to the props and ESCs discussed in this video.

• 6x3 KMP prop (Banggood); 
• 6x3 TGS prop (Hobby King);
• 6x4 APC gas prop; 
• 6x4 APC electric (knock off from Hobby King); 
• Turnigy Plush 40A ESC; and
• Turnigy AE-45A ESC.

I now have put 100 flights through the motor I am showing in the video and it is performing as well now as the first time I flew it.  Very smooth, strong and durable with very good torque and acceleration and top end speed almost equal to the EMAX motor.

As mentioned in the video, it is not as expensive as many of the other top end motors and paired with the fairly inexpensive Turnigy AE-45A ESC is the best value for top end motors I have tested thus far.

You can read Ryan Harrell's evaluation of this motor at his website following this link.

I would also encourage you to check out rcplanepirate's YouTube channel, he has been instrumental in helping me squeeze as much power as possible from these quad racing motor setups in my park jets.

Very pleased with how this motor performs, especially considering it's price😀

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott