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Jan 05, 2017, 05:40 PM
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Catalystmachine's Avatar
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The 4" FPV Racer Revolution is Coming! Are you ready?


As few as 3 years ago FPV racing was in it's infancy. The majority of people were flying racing machines around 250mm in size swinging 6" props. Then in summer 2015 everyone started to move over to 210"ish" sized machines designed to fit 5" props. Its seemed very sudden. All of the sudden... WHAM! 6 inch was out and 5 inch was "in". Now most racing quads you see on a track spin 5" props. Typically larger 6" props machines are used for Freestyle. Why did this happen? Why was there a shift to smaller size craft as the GO-TO race setup?

Answer: Advancement in power system technology

Summer of 2015 the Charpu QAV 210 led the way into the 5" craze. The designers realized as power system technology improved they could produce better performance for a race craft from a smaller package. 2205 and 2206 sized motors came out that could swing 5" props and make thrust values no one dreamed possible, back in "ancient 2014"! This ability to pack high thrust into a smaller package led the industry to progress to smaller craft. This means similar thrust/weight as a 6" machine but with less inertia. And as we all know inertia is the enemy of a racing craft. Higher inertia means it takes more power to change direction and directional changes are slower. It doesn't just stop there. There are other advantages to using smaller drone racers. Namely price and crash durability. In general price of smaller components is less than a comparable component intended for a larger craft pulling more amps. Look at 30 AMP ESC pricing compared to a 20 AMP ESC pricing, for instance. Then there is durability of parts. A larger craft has larger components that hold more mass. In a crash this means more force on parts which translates into higher stresses and more broken parts. The higher the mass the more broken parts. Its a simple equation.

At Catalyst Machineworks we believe there is an upcoming revolution on the horizon. This is a movement from 5" race craft down to 4" race craft as the "GO-TO" setup. There is a new breed of motor coming out now in the 1407 size which has the ability to produce unbelievable thrust for their weight swinging a 4" prop. Take the new Brother Hobby 1407-3600kv motor for instance. This cute little bastard only weighs 15 grams but yet can produce peak theoretical thrust (aka thrust test stand) of 750g on 4045 two blade props! Now you may say, "Yea but a 2205 can make 1400g thrust on 5 inch props". Well this is true, but a light weight 2205 motor also is around 27g - 30g, depending. So for both motors we have about the same thrust/weight ratio 50/1 but yet the 1407 motor has less INERTIA on the craft as you move it through the air. This means the craft as a whole has better maneuverability compared to a 5" machine, as long as you choose components on the rest of the craft with less weight in mind, ESC's, FC, PDB, Lipo, props, RX, etc, and most important the frame itself. All these items need to be selected to keep weight as low as possible. Designers of FPV electronics are making it easy too! With smaller and lighter gear coming out constantly. PDB/FC combos, 4in1 ESC's, smaller single ESC's, smaller lighter motors, smaller and lighter VTX. The list goes on and one.

Enter the Catalyst Machineworks SuperLight 4R. This is a project we currently have going on which is intended to lead the way into this brave new world of 4" racing craft. It is currently a prototype and we are actively flushing out the design to bring it to production. It builds on our popular SuperLight 5" machine we have been selling for a number of months now using the same design principles and elements. However, this one is designed around 4" props and the 1407"ish" sized motor as the ideal power plant to give this bird the ability to compete against and beat a comparable 5" craft. With the 4R we can produce similar thrust/weight but have MUCH LESS INERTIA than a 5" craft. All up weight (AUW) possible with this guy is around 165g before lipo. Its designed to be used with a 850mah - 1000mah 4s lipo. So AUW with 850mah of around 265g or so. The pictures below show my personal proto with an AUW of 175g before lipo. Mine is a fat ass since I don't have a proper FPV antenna on it and am using the optional arm braces. However, my team pilots are all receiving these prototypes soon for further testing and I can assure you theirs will be lighter than mine. Its sort of a competition between them lol.

So what does it feel like to fly this bird? Well, the top speed is similar to a very powerful 5" craft on 4s or 5s. However due to the massive reduction in mass it simply maneuvers better on the track than a 5". Acceleration out of a corner is faster. Deceleration into a corner is faster. Its easier to hold a line in the corner due to less momentum trying to pull you off line. When you make a mistake its much faster to correct. In three words. Its MIND BLOWING.

Videos coming soon... Here are some pics and specs of my proto.

http://www.catalystmachineworks.com/.../superlight-4r

Frame: Catalyst Machineworks SuperLight 4R
Size: 167mm
Bare Frame Weight: 38g (fully dressed with all fasteners and 3D parts)
AUW Possible: 265g "ish"
Frame Config: XL
Props: 4 Inch
Bottom plate: 2.5mm carbon finish (with option for 3.5 for fattys)
Top plate: 1.5mm carbon matte finish
Camera: Accepts 1/4" mini cam or HS1177
Ideal motor: 1407
Ideal lipo: 850mah 4s





















Last edited by Catalystmachine; Jan 18, 2017 at 04:54 PM.
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Jan 06, 2017, 03:52 AM
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danlatu's Avatar
hglrc pbf3?
Jan 06, 2017, 04:39 AM
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Catalystmachine's Avatar
Quote:
Originally Posted by danlatu
hglrc pbf3?
Yup.

http://www.helipal.com/hglrc-pbf3-ev...ontroller.html

That fits. So does a regular sized FC. However this type is ideal since its saves a ton of weight.
Jan 06, 2017, 04:46 AM
Fan of just about anything RC
SoloProFan's Avatar
Looks nice. Will there also be some protection for the camera? When it's tilted, it protrudes above the top deck, and could be hit in a crash.
Jan 06, 2017, 04:58 AM
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Catalystmachine's Avatar
Quote:
Originally Posted by SoloProFan
Looks nice. Will there also be some protection for the camera? When it's tilted, it protrudes above the top deck, and could be hit in a crash.
Yes sir...funny you point that out. This is actually one of the items on our list I plan to adjust for the production version. I am going to reduce the height of the post the camera swivels on. This will draw it down farther into the frame. Keep in mind that since the camera mount slides up and down on the two front standoffs you can adjust it's placement on the Z axis to your liking, in addition to camera tilt. However it doesn't really matter if that little camera gets hit. The red mount its attached to is TPU. It simply flexes. In a crash the camera just flexes out of the way and pops right back. Also, this frame fits the popular HS1177 sized camera by using a different (included) top plate and additional (included) hardware. I'll be taking pics of that setup soon and posting here.
Jan 06, 2017, 05:03 AM
Registered User
Did you really miss the opportunity to make holes for HS1177 style cameras in the side plates?
Im a little bit sceptical about the 2.5mm bottom plate. Even on 3 inch the high power setups have 3mm.
That aside, you are totally right: Lightweight 4 inch frames are really lacking, most are shrunk down 5 inch frames. My BH1407 3 inch setup is my favorite at the moment. With 3mm, HS1177 and 850mah 4S its about 290g though (~8 T:W). 4 inch with a similar weight should be even better.
Jan 06, 2017, 05:14 AM
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Catalystmachine's Avatar
Quote:
Originally Posted by Enurian
Did you really miss the opportunity to make holes for HS1177 style cameras in the side plates?
Im a little bit sceptical about the 2.5mm bottom plate. Even on 3 inch the high power setups have 3mm.
That aside, you are totally right: Lightweight 4 inch frames are really lacking, most are shrunk down 5 inch frames. My BH1407 3 inch setup is my favorite at the moment. With 3mm, HS1177 and 850mah 4S its about 290g though (~8 T:W). 4 inch with a similar weight should be even better.
No. We didn't. The frame comes with two top plates. One for the mini cams and one for the HS1177 sized heavy beast monster cams. It also comes with two sets of side plates. The ones in the pic and also some I have yet to take a picture of. Here is the CAD. We wouldn't leave the HS1177 guys out of the party. Can you imagine the fall out from that?!

With regard to the bottom plate thickness I know its hard to imagine running a 2.5mm plate and it being enough for general thrashing. However you need to keep in mind that the required thickness of your frame structure scales directly to size and weight. This craft is only 167mm in size (compared to typical 180mm 4" frames). Also, it only weighs 260g - 270g AUW WITH lipo. This is a massive reduction in mass. Less mass means you have less forces on the parts when you crash, meaning you don't need as thick a material on the bottom plate.

With that said. the production version will come in two flavors. 2.5mm for the serious racers looking to shave as much fat as possible and also a 3.5mm option.

Hey man! 290g isn't bad at all. Well done.
Last edited by Catalystmachine; Jan 06, 2017 at 05:31 AM.
Jan 06, 2017, 01:19 PM
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flydynamics's Avatar
Quote:
Originally Posted by Enurian
Im a little bit sceptical about the 2.5mm bottom plate. Even on 3 inch the high power setups have 3mm.
I'm flying a similar setup since September, different frame, tons of flights, tons of crash, still have to break a 2.5mm arm and a 1mm plate on it.
Like mentioned earlier, inertia is so low compare to a 500g machine that you literally use almost half of the power to complete a 180deg reversal (my quad is 268g with 850mA 4S pack)!
Inertia is also helping in crash with less damage etc ...
Very, Very few people have had to opportunity to fly a set-up like this at the moment since none are available in the North american market and I think only one available in Europe, with a different design that is way less simple and way less effective than the SL 4R imo.

Change always scares the masses until the masses see the potential of the change in the hands of the guys making the change happening
Last edited by flydynamics; Jan 06, 2017 at 01:45 PM.
Jan 06, 2017, 01:56 PM
Registered User
I don't see any "revolution" here . . . I was flying 1306s and 4045s with a lightweight camera and 4s 850mah on an Armattan Morphite a long time ago

Frame looks nice though!
Jan 06, 2017, 02:03 PM
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Catalystmachine's Avatar
Quote:
Originally Posted by TemjinStrife
I don't see any "revolution" here . . . I was flying 1306s and 4045s with a lightweight camera and 4s 850mah on an Armattan Morphite a long time ago

Frame looks nice though!
The Morphite frame is nearly twice the weight of the 4R, and weight is everything for this design and theory.
Last edited by Catalystmachine; Jan 06, 2017 at 03:18 PM.
Jan 06, 2017, 04:03 PM
Registered User
flydynamics's Avatar
Quote:
Originally Posted by TemjinStrife
I don't see any "revolution" here . . . I was flying 1306s and 4045s with a lightweight camera and 4s 850mah on an Armattan Morphite a long time ago

Frame looks nice though!
I did too in Spring 2015. and it was fun. Now imagine WAY more powerful motors; a 1407 on king kong 4045 is pulling 750g, a 1306-3100 on the same prop is pulling 450g !!!!!! Add the weight of the machine with battery being WAY WAY lighter than the frame with battery on 1306 (the difference in my set-ups between 1306 and 1407 was 70g !!!!!! See what's the deal is about ? Not mentioning that 1306 motors were not initally designed to handle 4S in the long term at that period of time.
Like I said, very very few people have flown these set-ups, yet; some will just say it's all hype, and some who will try it will understand that's there is no hype here, just facts, pure performance and fun !
Without trying it, it's impossible to know what's the feeling is in flight. Don't ask me how I know, I have a French kit that is in that range of weight and is just fantastic to fly.
Last edited by flydynamics; Jan 06, 2017 at 05:45 PM.
Jan 06, 2017, 04:28 PM
Registered User
Theibault's Avatar
Quote:
Originally Posted by flydynamics
I did too in Spring 2015. and it was fun. Now imagine WAY more powerful motors; a 1407 on king kong 4045 is pulling 750g, a 1306-3100 on the same prop is pulling 450g !!!!!! Add the weight of the machine with battery being WAY WAY lighter than the frame with battery on 1306 (the difference in my set-ups between 1306 and 1407 was 70g !!!!!! See what's the deal is about ?
Like I said, very very few people have flown these set-ups, yet; some will just say it's all hype, and some who will try it will understand that's there is no hype here, just facts, pure performance and fun !
Without trying it, it's impossible to know what's the feeling is in flight. Don't ask me how I know, I have a French kit that is in that range of weight and is just fantastic to fly.
I'm surprised you don't have a 4R. As a Catalystmachine team pilot, I would have thought they would have you testing it.
Jan 06, 2017, 05:24 PM
Registered User
danlatu's Avatar
My first build was a diatone 160 grasshopper on 4" props. Arms were weak on 4s and had crazy oscillations with dys 1306.
Could not carry a gopro and decided to move on.
1407 4 INCH?!? LOS flight (2 min 27 sec)

Reports of this setup are motors hot when coming down, curious to see your findings.
This is still sparking my interest.
Jan 06, 2017, 05:43 PM
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flydynamics's Avatar
Quote:
Originally Posted by Theibault
I'm surprised you don't have a 4R. As a Catalystmachine team pilot, I would have thought they would have you testing it.
As mentioned in the first post, the frames are on their way to team pilots, so I am waiting for mine to be delivered; should be flying it next week intensively knowing exactly what will make it perfect since I'm flying something similar but yet different in geometry since September. Since September I have been testing the concept and I can not tell you how good it is.
Hope that clarify your question, lots of testing before having a frame out of production.

Like someone posted it, Brain Drain has also been walking that path recently as same objective often lead you to the same conclusions.
Jan 06, 2017, 05:50 PM
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Theibault's Avatar
Quote:
Originally Posted by flydynamics
As mentioned in the first post, the frames are on their way to team pilots, so I am waiting for mine to be delivered; should be flying it next week intensively knowing exactly what will make it perfect since I'm flying something similar but yet different in geometry since September. Since September I have been testing the concept and I can not tell you how good it is.
Hope that clarify your question, lots of testing before having a frame out of production.

Like someone posted it, Brain Drain has also been walking that path recently as same objective often lead you to the same conclusions.
Excited to hear your thoughts on it. I'm intrigued by this frame.


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