Lowered Mikado Head Setup

[BennyTRD]

A friend and I came up with an idea last winter on how to incorporate the swash driver and head block into a 1 piece design. This will aid in getting that perfect phasing setup, and also brings the weight of the heli closer to the disc. While this is hard to prove, it should make the heli roll more axially because of the heli's mass is closer to the main blades.

After a few prototypes and testing, we figured it out. Since the spring I have been flying this lowered head setup on my 600SE, and shortly after that my 6003D as well. I have had zero issues and both heli's continue to fly great. It also makes the heli a little more aesthetically pleasing without having all the excess height about the canopy.

What this consists of is a custom hand machined head block that includes mounting holes for the swash driver arms. Also, a stock Mikado main shaft that has been cut down, and a new hole drilled for the Jesus bolt. The grip links would have to shorter, which we easily made from rod stock.

We first started with 6061 T6 Alloy, which worked fine and polished very nicely. We have determined that Mikado uses a 2025 Alloy for their head block, which is pretty much the standard for most aviation companies. This is fine most application's out there. Here are a few specs about the different types of alloy out there.

Material----------Density-----Shear-------Yield------Ultimate
6061 T6 Alloy .095 lb/in3 30,000PSI 40,000PSI 45,000PSI
2025 T6 Alloy .098 lb/in3 37,000PSI 58,000PSI 72,000PSI
7075 T6 Alloy .102 lb/in3 48,000PSI 73,000PSI 83,000PSI

A fellow Logo pilot was having issues this year with head blocks shearing off in flight along the axis of the 4 bolts that secure the head block and upper yoke together. This was mostly caused due to the slight gap between the 2 parts from machining tolerances.

So what we decided to do was go with the 7075 Alloy and make the upper yoke and head block a precise fit, having to heat the upper yoke up then mating the 2 parts together. We made a few head block’s for him using this Alloy and tighter fit and things have been working out great for him with no issue's. Sorry to post these man!!






Some other things we decided to change were making the hole for the spindle smaller. This leaves a lot more material at the weakest point of the head block, improving its strength greatly. The stock head block has a 10mm hole for the spindle, and we made ours 9.6mm. This still provides ample room for the spindle under all conditions, even if your dampeners are shot. We also made the tolerances for the main shaft hole better with a much tighter fit. One other change from stock is the pinch bolts on the lower portion of the head block are on opposite sides for ease in cinching it down to the main shaft.

Here are a few pictures of this setup installed on my 600, and a few of the head block itself.














This setup will work for both the Logo 500 and 600. We also have a similar setup for the 400 in the works as well.

It's a slow going process making these as all the drilling, reaming, tapping, etc, as it's all done by hand. We use a Milling Machine with a Digital Read Out for making things as precise as possible. We also use a machining lathe in the process for shortening the main shafts and turning the head blocks themselves. Chris is a very talented machinist, and takes great care in making things as perfect as possible. Each piece takes about 2 hours to cut from stock, drill, tap, polish, verify fitment, etc.

We have about 20 NIP main shafts to cut down and re-drill, and have a few of the head blocks made up at the moment. So basically, we are offering these up to the Mikado community if anyone is interested.

What you'll get is a 7075 Alloy precision made head block, 2 shortened and re-drilled Mikado 4075 main shafts, and a set of 42mm links to replace the longer links. All the other parts and hardware is already on your existing head. You'll also need to heat the black upper portion of the head up to install it over this headblock as the machining tolerances are a lot tighter. Simply use a heat gun for 30 seconds or so, or do the oven method.

Because of the time envolved in making these up, we would be asking $100 for the complete setup. We had to purchase quite a few specialty reamers, and other tools to make these as precise as possible. Keep in mind your also getting 2 $10 Mikado shafts that are already cut and drilled to the appropriate lenght and size.

I will post a few pictures what you will get for the complete setup this evening, but again it consist of the head block, 2 main shafts, and a set of links.

So if your interested, send me a PM. Or if you have any questions, just post them in this thread and I'll be happy to reply. Thanks for looking guys!!

[vteknical]

Interesting. Perhaps you can shoot a video of someone giving that Heli a serious smack down. I think it will build credibility and trust if you intend on going to market.

[rcmarty]

interested in the thread : sub

martin

[Chris_M]

I like it! What about the distance between main and tail blades now...are they close? How much shorter are the shafts now?

[BennyTRD]

Here's a video of Dmitry flying the non lowered version of the head block we made for him. This is tame flight for him by all means. If it will withstand his abuse I'm sure it will work for anyone.

[ame]http://www.youtube.com/watch?v=ljsogx0GP6k&feature=youtube_gdata_player[/ame]

And yes Martin, that is the version Chris settled on for the 400. All of the other ones made will be exactly like that one.

[BennyTRD]

Originally Posted by cmar143

I like it! What about the distance between main and tail blades now...are they close? How much shorter are the shafts now?

It's closer yes but still lots of room. I have roughly 100 flights on these between the 2 heli's and never had an issue for blade clearance. I also have 623mm blades on the 600.

The shafts are 23mm shorter which using the stock link lengths for the servos from the manual lines that swash arms up perfectly 90 degrees.

[SFACV]

Hi Ben,

Been a while, looks like you have been busy. I have to do some measuring but I think this will work on my Camera Rig. If it does I will take 2.

For anyone else Looking at this option. If Ben is running this on his machine and making it available there is no question on quality or cost. You will get precision parts and he won't be ripping you off. For the time and expense required to do this for a few pieces I am surprised that they are only $100.00

[prototype3a]

Have you considered using 7475-T7351?

It is lower strength compared to 7075 but should have a much higher resistance to fatigue failure.

Material K_1C(ksi*sqrt(in)) Yield(ksi) UTS(ksi)
7075-T651 26 73 83
7475-T7351 47 63 73

[BennyTRD]

Originally Posted by prototype3a

Have you considered using 7475-T7351?

It is lower strength compared to 7075 but should have a much higher resistance to fatigue failure.

Material K_1C(ksi*sqrt(in)) Yield(ksi) UTS(ksi)
7075-T651 26 73 83
7475-T7351 47 63 73

To be honest, it's hard enough to find 6061 around here. We ordered the 7075 out of the US as we could not find it up here in Canada. The 7475 looks like a good alternative however, but for our model heli's, the 7075 alloy will be more than adequate.

Originally Posted by Wbird

Hi Ben,

Been a while, looks like you have been busy. I have to do some measuring but I think this will work on my Camera Rig. If it does I will take 2.

For anyone else Looking at this option. If Ben is running this on his machine and making it available there is no question on quality or cost. You will get precision parts and he won't be ripping you off. For the time and expense required to do this for a few pieces I am surprised that they are only $100.00

Hey Conway, long time for sure. Let me know how you measure, up and I'll get what you need out to you. You got to start making it out to FF's again!! Thanks man.

[Sean212]

This looks really good! Great work! Just curious on what you guys might charge for extra mainshafts and links? I would hate to get one, crash a couple times and not have any backups. Since you would be the ONLY person to get spares from.

[Twister773]

Boom strikes and tail blade strikes shouldnt be a problem using 693's and 105's on an se?

[BennyTRD]

Originally Posted by Sean212

This looks really good! Great work! Just curious on what you guys might charge for extra mainshafts and links? I would hate to get one, crash a couple times and not have any backups. Since you would be the ONLY person to get spares from.

Yes, got the market cornered here!! All joking aside it does take some time to cut the shafts down and re drill so I think $15 per shaft is pretty fair. And for an additIonal set of links, that will set you back a whole $2.

Originally Posted by Twister773

Boom strikes and tail blade strikes shouldnt be a problem using 693's and 105's on an se?

I've been flying my SE in that configuration all year and have not ran into an issue. There is still plenty of clearance for the main and tail blades.

[Twister773]

Originally Posted by BennyTRD

Yes, got the market cornered here!! All joking aside it does take some time to cut the shafts down and re drill so I think $15 per shaft is pretty fair. And for an additIonal set of links, that will set you back a whole $2.



I've been flying my SE in that configuration all year and have not ran into an issue. There is still plenty of clearance for the main and tail blades.

Even at 1-1100 rpm sport flying in normal mode? I think I may have to try one for my se

[BennyTRD]

I haven't tried It that low. But at 1500 there is no issue I ran into. As long as your dampeners are in good shape I can't see it being a problem.

[GimpyGolden]

Ben
Any chance they will be available through Ken like the Canopy mounts?(Which I love BTW)
I'm guessing the head can't be used with stock length shafts or could the swash raised to level the follower arms?

[Redlight11]

Looks great. Is there any perceivable performance increase?

[Cat1]

Hey Ben.... Thought I would throw in a few extra pics of the blocks and the Logo 400 version.... The 400 Version is slightly shorter and really makes the SE version look "right"

This "project" has been very rewarding as the visual effect of the lowered block really makes the machines look very good.... hope the Logo crowd enjoys the "look"

Chris

[BennyTRD]

Originally Posted by GimpyGolden

Ben
Any chance they will be available through Ken like the Canopy mounts?(Which I love BTW)
I'm guessing the head can't be used with stock length shafts or could the swash raised to level the follower arms?

Ken has a set right now that he is putting on his 600. I would imagine that he will take a few sets to have in stock, but not 100% at this point.

I doubt the swash would go up that high to get the arms so that they wouldn't bind on the negative side. You could make up some links I suppose to accomplish this though. Is your concern more that you have an abundance of mainshafts around?

Originally Posted by Redlight11

Looks great. Is there any perceivable performance increase?

It's one of those thigs that's hard to prove. You have to have a pro pilot (which I'm not), fly the stock setup, change the head parts out, and fly it again to see if there was a noticable difference or not. In theory however it does make sense that having more the weight of the closer to the disc would help with the pendulum effect (caused by the low slung battery packs), and possibly help the heli roll more axially. Having more weight to the higher up to the CG might possibly make the heli stop crisper. Again very hard to prove this correct though.

But what I can say is both my Logo's fly very well, and theres not a thing I would change at this point. Well, maybe 100C packs would be nice!!

[BennyTRD]

Here's a pic of the packaging, and what each kit contains. Again, you get the head block itself, 2 mainshafts (plus the snap rings), and a set of 42mm links.

[NovaCX12]

Are you guys planning on making standard height blocks? Looks very impressive