Scale RC Helicopter Build - Fitting Mechanics Into A Scale Fuselage 

@majorsmackdown - Glad you found the foam mounting works well too. 👍

Thanks for watching

good tip i am in the process of building this fuse using a stretched 550E V2 as well! 1st build so i am getting over the shock of this daunting task i have taken on....lol

Thanks 👍

Glad you like it

Very welcome

Glad you liked it

Great to hear - good success with your 222 build.

Thanks 👍

F Balb, I took a completely different approach to mounting my stretched 550E. For those who wish to build something similar, here it is and why I did this. The Funkey Bell 222 has a large area of unbraced 'flat bottom', and placing the narrow mechanics (typically 50mm or so in the centre and with all its weight, this automatically gives rise to the chance of undue flexing and both parts wanting to go in opposite directions during spool-up and other times. Even with extended 'arms' at the front and rear mounting points, this still doesn't address the issue. I cut a piece of thin ply 365mm x 140mm, chamfered and shaped at the rear and front sides a small amount to fit the fuselage shape there. This size takes the ply right to where the fuselage begins to curve and give natural rigidity. I calculated where the mounting bolts for the mechanics would be (183mm long/96mm wide for mine), drilled the four holes and fitted blind 'T' nuts from underneath the ply, then glued the ply down ensuring almost full ply to fibreglass contact using JR WELD. Johns goop will probably be as effective but we don't seem to have it here in New Zealand. There are NO holes through the fuselage using this approach. The result is a strong and rigid support for the mechanics with absolutely no bend or twist issues, and the extra weight is negligible. The overall height of the mechanics can then easily be attained by shims/ply etc. In mine, the 6s battery sits across the fuselage in a low-profile ply mount glued to the floor ply and is directly behind the front-most bulkhead. CG is almost dead centre to the mainshaft. The mainshaft should have about 5 degrees of forward tilt, similar to the Bell 206, but sometimes this is difficult to achieve. I kept the mechanics quite low and used a longer mainshaft to get this, plus the 87mm odd height from the top of the doghouse to the centre of the bladegrips. I also made ply bracing sections further back in the fuselage where it is necessary to cut the bulkhead supplied by Funkey, plus a 'horse-shoe' shape ply brace behind the doghouse open section where more flexing can occur. Two extra metal straps are bolted between the CF frames and the fuselage some 60mm behind the mainshaft to give extra lateral support.

The Jet & Long Rangers are a much easier fit, primarily because you can slide them in over having to drop them in. Same fitting principles apply for sizing and making your spacer mounting blocks. Upper frame bracing will require some thought. I've never done a 600EPro /Jet - Long ranger, I have done a couple 600ESP ones however. Really easy compared to the 222's. The 600E Pro will work fine, but you'll have to cant the battery tray fairly far forward to get the CG on the mark (lots of room in the long ranger for that). The one draw back with the Pro version (other than the head sitting lower and looking kinda funny on a Long/Jet ranger), is the pitch and aileron swash ears are facing forward with the elevator swash ear at the rear. This will necessitate grinding out two holes in the front of the dog house that extent below the forward leading lip so it doesn't look the best, and compromises strength a little bit, but it works. This again is why the 600ESP version is one of the best set of 600 electric mechanics for scale projects like these since the aileron and pitch ears are at the rear where there is always more room in the dog house :-)

Many thanks John for your excellent advice. I see what you mean regarding the 600 pro not being ideal for fitting into the fuse. I'll probably try to get hold of a used ESP and hopefully convert it to flybarless setup. Alternatively, I could try to convert one of my Hirobo Sceadu's to EP. Regards, Marcus

"Having trouble finding one that will work?" Really? I just did a Google image search for "low profile servo" and every brand under the sun showing their different models of low profile servos popped up on the screen. Must have been over a hundred of the them. I have Hitec HS-77BB's in one and Blue Bird BMS 705's in the other. I wanted to use analog servos with plastic gears to keep weight down and current draw (if/when they stall) low. Had to cut the hole in the plywood servo tray slightly larger of course to fit a standard size servo.

I added it in the description (got the question before), but it's just normal closed cell EVA foam. You know, the type of foam most blade holders are made from, kids flip-flops, or those 2x2' interlocking foam floor mats. No idea however if or how long it holds up to nitro oil. I've never tried it in a nitro environment, only electric.

Sorry, other than finding a used set of ESP mechanics if you can't find any Phoenixtech 600ESP ones in stock at Motion RC or direct from Phonextech RC, I don't know of anything else that works with little in the way of modification.

Like most scale builds, yes, the Wolf was tail heavy as well. I don't like adding extra nose weight to an already heavy scaler unless it has a useful purpose and as many know, I use separate RX batteries on all my larger machines. If you notice, there is a fairly large 2S 3000mah RX pack mounted to the front bulkhead. The weight of that pack brings the CG back into a usable range. There was still a little rear drift but not excessive and was correctly mechanically with a tad bit of mechanical swash forward tilt adjustment. Not an ideal "text book" solution since when inverted the tail drift is then twice as bad, but since it's a scale build, I'm rarely inverted with it, and when I do throw it around a little bit, it's just simple loops, flips, and rolls; nothing where inverted drift is noticed. The good old game of compromise in this hobby - add unwanted weight, or add unwanted inverted drift :-)

Soft mounting works regardless of size. As for upper side bracing also benefiting from dampening... To fully explore that, we would have to dive into the deep hole of vibration analysis which is a massive and complicated topic. Energy, frequency, harmonics, natural resonances, changing stiffness levels of the fiberglass and dampening media that are both constantly changing at different temperatures, etc. - so many variables. Those soft and small aluminum braces are not that rigid so already have a degree of energy absorption/dampening that seem to do the job. I have however played with dampened side mounts to see how much they further help, and they do seem to help a little bit on smaller scale models running at higher head speeds. Using dampened side mounts on larger scale models over the years, I've noticed little to no change so it comes down to effort in relation to benefit. Of course, every scale build is different so if you notice excess vibration energy migrating into the dog house or upper half of the fuselage, then having dampened side mounts is one method (of several) to try.

@@Rchelicopterfun I have an air Wolf 600 size just looking now for the complete internals far as the frame everything to complete a billing the helicopter I just emailed you just like to know how much the pricing will be everything everything is no

As far as I know, they are not available separately, they only come as part of the retract set. Best to check with a FunKey distributor of course. They may even have some odds & ends kicking about.

See description. I also say in the video at 16:21

@djpj54321, on my Funkey fuselage page on my web site ( www.rchelicopterfun.com/funkey-fuselages.html ), I show all the internal dimensions of each Funkey fuselage in their 3 size ranges. You would have compare those critical internal dimensions of the FK 550 Bell222/AW against the outside physical dimensions of various 550 size mechanics. Without looking closely, I would think the Align T-Rex 550X might fit, but that is just an educated guess without researching the exact sizing of that helicopter. Even if sizing works out, battery placement is another major consideration to look into, especially in the FK Bell 222/AW because the front canopy is not removable. Ie. sliding lower battery trays won't work since they won't be accessible.

@@Rchelicopterfun Thanks for you answer, really appreciated! I started reading your articles, very interesting and informative. I might go for the 600 size Airwolf after all. Didn't decide it yet.

Nitro Install Recommendations... Just one - convert to electric ;-) Seriously, nitro in scale is a royal PIA! I flew nitro for years in scale and I can't say there is one single redeeming quality (for scale anyways) other than the smell of the exhaust. Nitro will require an expensive (perhaps even custom) exhaust system, overheating issues of the engine in scale are common, engine tuning is always changing, flameout's are common so you better be very proficient at auto-rotations (much harder with scale since there is more weight and energy control during the auto is unforgiving) , you will need to cut at least one large hole in the belly for the fan cooling of the engine, the inside of the fuse will constantly be saturated in nitro oil, the high frequency vibrations from the engine eventually start cracking the fiberglass, and the starting shaft will eventually chew the doghouse all up. If you are just getting started in RC helis, my advice is to first and foremost get 100% proficient flying your 50 nitro in pod & boom format first (if you can't already), before even entertaining the idea of scale. You don't have to be able to fly aerobatics, but you should be totally comfortable flying and hovering in all upright orientations, including nose in. At that time, you can revisit the virtues of electric power vs nitro in scale applications and decide if you still want to stay with nitro or convert/get an electric heli for the scale build. My scale heli page on my website may help you further: www.rchelicopterfun.com/scale-rc-helicopters.html Good success Karla and glad to hear you are taking up the hobby.

Thank you for your reply, it is very helpful, I have found a conversion kit for the Century Raven, if you don't mind me asking, what size of motor would you recommend and what other components would I need to finish a confersion ? Thank you again for your help, have no one close to me to help so I'm in a sense winging it on my own here.

Sorry No Idea - Never done one and too many variables to consider. Suggest posting the question in one of the better heli forums such as HeliFreak or RC Groups.

Every build's spacer blocks will be slightly different. As I mention in the video starting at 15:35, mounting block height is a process of trial fitting the mechanics with the boom doughnut in place. You then add spacers under the mechanics to determine the best overall height for your application and what tilt angle you want for adequate clearances. You would then measure the space between the front and rear mounting locations and build up your spacers. As I mention, it's best to error on the side of the spacers being a little too thin since you can then add spacers to bring the height up if needed.

Sorry, don't know.

@Bobby McKay - I made them by modifying and turning them on my hobby lathe from an off the shelf set of scale jet retracts. Sorry I can't remember where I got them from (likely flea-bay since I'm a tight ass). I just did lots of Google image searching for scale retracts that were similar to Bell 222's. Once I had some possible ones narrowed down, I got the exact dimensions from the product pages and made some crude cardboard mockups to see if they might fit/work before ordering. Yes, it was lots of work and I'm still using the Funkey mechanical retract hubs. Just replaced the sprung wire with the aluminum struts. By the way, the Funkey sprung wire gear works better (better impact and energy absorption), but as long as your landings are gentle, these re-purposed inexpensive jet aluminum strut type ones are holding up. Have fun with your scale build - 🙂

@Bobby McKay - I think I found them: www.turbines-rc.com/en/struts-sets-and-full-sets/682-class-25-prodesign-v2-scale-metal-wheels-landing-gear.html Mine came direct from China I recall, so I'm sure this is not the place I got them from but I'm certain these are the same ones. You have to be prepared for a fair amount of modification to them to get them to work (at least on the FunKey fuse using their mechanical retract system). No idea with the Vario fuse? I had to use different size wheels as well.

@@Rchelicopterfun Thanks so much John!! You helped me out big time! I bought the gear from that link and will modify to fit my set up!!

Hi Fabien, The set of tri landing gear struts I'm using also came from hobby king so I assume they are likely the same ones you have? I had to modify them substantially however to make them fit. I had to shorten the aluminium struts on the two rear winglet ones. Drill out the plastic pivot blocks in the Funkey mechanical retract mechanisms so the struts would fit a little ways up into the pivot blocks. Metal epoxied them into the blocks. I also had to shorten the wheel arms on the rears and use smaller diameter wheels on all 3. Much of that modification work I did on my little hobby lathe, but I'm sure a Dremel tool or file and a standard drill would also work if you take your time. I botched the first set I had so it was largely a frustrating trial and error modding process. The rear ones in the winglets still hang down a little low when retracted (you can see the wheels slightly when retracted). They are not nearly as good as the stock wire ones when it comes to robustness and hard landing protection, but no question, they look way better than those ugly stock wire ones.

Hello, thank you for your answers. yes I have the same trains that you have mounted. Now, I know how to make the trains change;) I will also get your ideas for the connection of the chassis given the lack of space. This will help a lot of people who want to make a little more model this fuselage. good continuity and thank you again

Full size yes, but almost all RC helicopters have their tail rotors on the right side, including the Align T-Rex 600ESP which are the donner mechanics used in both these scale fuselages. FunKey (the fuselage manufacturer) also knows this, so they make the fuselage with right tail rotor exit position on all their 550 & 600 size fuselages.

I have links on my FunKey Fuselage Review Page: www.rchelicopterfun.com/funkey-fuselages.html I only do custom scale builds for local pilots I know.

Nope. Too small.

@@Rchelicopterfun Can you tell me what size fuselage I can use THANKS

No Idea whatsoever other than looking for 450 size ones and modifying as required.

@@Rchelicopterfun Ok THANKS

It's EVA foam - details are in the description. BTW, Phoenixtech (now carried at Motion RC) still makes the 600ESP clone mechanics and they to this day remain the single best electric 600 size mechanics for 50/600 size scale projects due to lower motor location, integrated elevator A-arm anti-rotation, and having the pitch and roll quadrants of the swashplate on the rear instead of the front. Nothing wrong of course with the 550X, just more fitment compromises as you've already surmised. Happy building.

@@Rchelicopterfun Oh wow, thanks for replying!! Yes, I am looking at the Phoenixtech for awhile, over an year it is out of stock at Motion RC. Enjoy a lot all your videos!

As stated in the video, you size and make them yourself.

thanks!!

I cover collective pitch setup for all flying styles including scale in my setup & tips eBook: www.rchelicopterfun.com/rc-helicopter-tips.html

Since almost all collective pitch helicopters on the market today are capable of aerobatic flight (if one wants to set them up & fly them in that envelope), the choice is cut and dry. High performance mechanics are about the only things we can use in scale projects just as with these two 600ESP scale examples in this video. And yes, they have more than ample power to lift the added mass of a fuselage. I even perform light aerobatics with the airwolf model; so even with all the extra weight, you can still toss them around if you so chose. I'm obviously not referencing the really big scale helis from Vario or Roban which are a completely different ball game. One thing for sure, you will likely never wear out a set of high performance mechanics when flown gently regardless if you keep them pod or boom or skin them with a fuse 🙂

The 600 size Funkey Airwolf fuselage is around $500-550 USD depending where you source it. You would need some sort of mechanics to install in them unless you want to custom make it all which would likely cost more than just getting a bare bones heli kit. Assuming just normal bare bones mechanics, another $400 USD or so. We all build & put these things together ourselves, so no idea what someone would charge to build it for you? You would have to ask around in the RC helicopter community or local hobby shop/s in your area. I used to do one or two custom scale builds a year when I had the time and my usual labor rate ranged from $1000 USD to $2000 USD depending on the model and electronic systems on board. That was of course for a working and flying helicopter, fully flight tested so anywhere from 40 to 100 hours of work involved over the course of a month or two. Without all the setup, programming, and flight testing, a skilled & experienced builder could likely put a non flying one together in 10 to 15 hours if it wasn't anything too fancy or involved.

I cover this info on my FunKey fuselage page: www.rchelicopterfun.com/funkey-fuselages.html All kit form. Apx finished flying cost $2K to $3K USD component selection dependent.

Shape it? I don't understand as there is no shaping required. It comes from FunKey as a fully molded and painted fiberglass fuselage all ready to accept the mechanics. I cover this in detail on my FunKey fuselage page if you are unsure of how scale heli fuselages are generally configured: www.rchelicopterfun.com/funkey-fuselages.html

Problem is I'm in SA n no one sells this helicopter this side

So seems like I'm gonna have to build it myself

Hi Martin, I'm running both of these 100% stock (600mm symmetrical main and 95 mm tail). No issues at all with tail rotor authority, but that's also never running much lower than 1500 RPM head speed (1450 would be the slowest I would recommend). If you want to drop the head speed lower, then you do have to think about different blades, but you then also have to think about a lower KV motor.

@@Rchelicopterfun Thanks John for the info !

You may want to check out my scale RC helicopter page on my website which answers most of these questions: www.rchelicopterfun.com/scale-rc-helicopters.html As that page states, you must be an experienced & proficient collective pitch RC helicopter pilot before even considering scale and models like these. They are not for beginners. Before I even consider taking on "custom scale" builds for others, I screen thoroughly to ensure they are already good & experienced RC helicopter pilots with at least some time flying larger & heavier models. These thing behave very differently from a tiny micro CP heli after all and require a strong understanding of the mechanical and electrical systems within a larger collective RC heli. If that describes you, you can contact me through my website and we can discuss further what a custom scale project would be worth as much depends on the specific model.

Just enough for the front frame edges to fit under the dog house.

@@Rchelicopterfun thank you so much for the quick response,you definitely answered my question What I should have asked is how much do the mechanics need to be tilted forward in order to achieve level flight to keep the look of scale,or is that not necessary,any input would be greatly appropriated,your video was very helpful and gave my a bunch of confidence :)

You actually want the mechanics as level in the heli as possible. The more they are tilted (forward in this case), the more the fuse will be tilted (backward in this case) while in a hover, and that certainly doesn't look correct or scale. So level as you can possibly get them and if you have to tilt for clearance, tilt as little as possible.

@@Rchelicopterfun you are too kind sir thank you much for clearing that up for me

Most welcome - have fun with your build 👍

Glue... Just regular Household Goop. Very strong stuff - same basic adhesive as Shoe Goo, and that is used in bonding shoe soles. That said, we are only lifting the weight of the fuselage, perhaps a pound or two? The rest of the weight including battery weight is totally carried by the mechanics; so actually, very little weight is being carried through the mounts. As for type of foam, whatever lightweight, soft, vibration absorbing closed cell stuff I can find. EVA (Ethylene-vinyl acetate), is the most common, and what the boom doughnuts are made from. My two sources are those common interlocking foam floor tiles that you can get pretty much at any hardware or home center, or cheap yet soft kid's flip-flops which I've have to use in a bind.

Airwuof

@Christian Harm - Almost as sad as your comment. That's the ONLY side of the boom it can be located due to the fact the FunKey 550 & 600 size Bell222/Wolf/206/206L/109A & AS350 fuselages only allow for right side tail rotor placement because the horizontal tail fin mounting plate is on the left side of the boom. The fin mounting plate is molded right into the fiberglass, and I'm certainly not about to go to the massive amounts of work required to cut off the end of the fiberglass boom, rotate it 180 degrees, redo a bunch of fiberglass & fill work (adding extra boom weight on an already tail heavy fuse), and then have to repaint it; which would look terrible given my limited air brushing and paint matching skills, just to have the tail rotor on the left side. Life is too short, time is too limited, and I honestly don't care which side the tail rotor is on... I'm more concerned with how well they fly. Why does FunKey do this? Because right side tail rotor placement is the standard on almost all off the shelf RC helicopter mechanics, including the 600ESP; so that is how FunKey's fiberglass fuselage molds are also configured - for right tail rotor placement. This way, their fuselages will work with the majority of RC helicopter mechanics on the market.

@Christian Harm 'ever heard the term "rivet counter"?

@@ChickenHawk841 Once again, I didn't want top blame anyone. I am also not a rivet fetishist. But the side of the tail rotor you can even see inflight. For me e.g. I am sad that my Vario "Airwolf" in fact ist not an Airwolf, as the base of the model is a Bell 230, and not 222, as the original. You can see it immediately when looking at the tail. The Hull in this video is a correct 222 hull, which gives her an impressive inflight look. If the tail rotor would be at the correct side, it would be a perfect inflight look.

Scale fuselages are almost always sold as the fuselage only, you get the mechanics separately. There are a few exceptions. I cover this topic in detail on my scale RC helicopter page: www.rchelicopterfun.com/scale-rc-helicopters.html