WHATIS THE BEST BLEND OF STRENGTH 7 LIGHT WIEGHT. I HAVE SEEN THE ROCKET CITY TYPES WHICH ARE STRONG BUT SEEM TOO HEAVY? ALSO OTHER HARDWARE SUGGESTIONS SUCH AS LINGAGES & RODS.
THANKS!

MK ... see www.probuild-uk.co.uk ... also try looking for the kevlar ones many people are making now.

I really like the MK Alum. Horns. At about 3.5 grams each, weight is not an issue. Strong and look really good.

On my Diablo 2000, which is almost ready, I used some of the 2-56 carbon fiber rods from Central with the HD 2-56 ball joints on the servos and the surfaces. For the elevators, I used the Hanger 9, titanium rods. They are heavier, however I needed the weight in the tail. Not that it added much.

I have tried to find the CF control horns here in the US, but with no luck. Ansano makes some, but Quique doesn't import them. ZN Line, makes some too, can't find them either.

I use the MK horns...They are sexy looking and light....I also use the MK ball bearing clevis connectors and the MK ball link connectors....They are not the cheapest setup but they are in my opinion the best horn's out there....

Tettra or IM products makes a horn that is a bolt with the Aluminum threaded nut that captures the bolt...Also has a finish washer for the bolt head side of the horn....These look decent and are a touch cheaper....

These are available from Central Hobbies.


For control rods The Central CF rods are the tops....Use the Titanium ends and you have lots of choices for which thread and the diameter of the rods.....They are super light weight.....If $$$ is more of an issue than weight they also sell stainless steel fittings rather than the Titanium ones....These rods are the best available period......


If going to the giant scale stuff like 30%+ The Hangar 9 Titanium links are great too...they have a right hand and a left hand thread on opposite ends....so you can use a little wrench and tighten up the linkage like a turnbuckle.....This works good on the Big stuff but is not as light as the CF stuff....Even though I would venture to say its close to the stiffness of the CF ones just heavier.


Rocket City stuff is great on the big planes but pattern style models I like the MK clevis and ball links....


Troy Newman

I would like to know who makes these red ball bearing clevis and connector and where can I purchase them at?


Don

IM USING MK HORNS ON MY NEW MATRIX THE ALIMINIUMS ON ARL,ELV AND IM USING THE MK OFFSET HORN ON RUDDER. LIKE TNEWMAN SAYED THERE SEXY AND LIGHT
CHEERS
MICHAEL

You can purchase them at

www.centralhobbies.com

The red ones are actually almost bright pink in color...They are color coded by size....2mm, 2.5mm, and 3mm....The 2mm ones are black the 2.5mm are the hot pink and I have never purchased the 3mm ones so I don't know.....

I use the 2mm version with 2-56 and will drill them out for 4-40 and I have used the 2.5mm for 4-40 thread.

In my opinion they are the best you buy...They have a small ball bearing race that provides smooth action and is slop free the clevis is held together using a 2mm screw...I use a nut on the back side for a little safety factor but have never had one of the bolts unscrew even when not using the jam nut. I also replace the 2mm bolts with socket head versions. Dubro makes them for RC car applications.


That pattern model in the picture also uses the Mk bellcrank for elevator control...Thats the red arms coming out of the fuse....These are also available through Central Hobbies....Its good stuff....Not the least expensive way to go but I have been flying the MK stuff since about 97' and never had a clevis or ball link fail or get slop...In fact They are as tight today as they were when installed new.

They work great on the MK aluminum control horns.....but if you are using just a 6-32 bolt as a control horn they will work there also.


Hope this helps


Troy Newman

I use 6-32 bolts not sure of size and Rocket City type ball links. Light, solid and cheap!

WHAT IS YOUR TECHNIQUE IN GETTING TO THE BELL CRANK TO ATTACH THE PUCH ROD INSIDE THE FUSE?

The Rocket city stuff is a close second as for reliability.....Its heavier on average and will get sloppy over time. Especially on the big planes....But it does beat the MK stuff on price.....Like I said before the MK stuff is not the cheapest on the market but it is the best.

I have a couple planes with well over the 1500 flights mark and the MK stuff and Central CF rods are still as good as day 1.....This says a lot for the quality and performance of the stuff....


I know that spending money is not always a solution to the problem....In my opinion these clevises and ball links are worth it....They can go a 6-32 bolt and get the same functionality as the MK aluminum horns but for the same length the Horns I think are stronger...I have broken 6-32 bolts over time as the metal fatigues and weakens never had a MK aluminum horn fail.....


Over the years I have learned that a good pattern model is one you don't have to perform maintenance on.....and linkages are the key to the way it flies



Troy

I have to agree, the MK stuff is the BEST, bar none. It's light, strong, tight and smooth.

It also costs a fortune. But you can pretty much rest assured it won't loosen up or become sloppy over time, and i have not seen one break yet. I HAVE seen a titanium end pull out of a C/F rod on a bellcrank assy, sending the plane to it's death. But it was glued in with regular epoxy, and the rod wasn't treated or prepped. (roughen the inside and clean with a pipe cleaner and alcohol).

But I've yet to see the MK stuff break, although I have heard of quite a few of the MK bellcranks broken when used on a Typhoon 2000. Not sure why, but I think it has to do with the width of the fuse and engagement of the link.

-Mike

#1 the linkage needs to be strong. Also needs to be maitencance free as you won't want to take it out and look at it every week. If I used a MK unit I would use the Central Hobbies 3/16" CF pushrod with a 4-40 Titanium fitting...Then use the MK MKD0891 BB rod adjuster 2.5mm


This BB rod adjuster is a Ball link type device...I would lock tight the nut and screw securing the link to the MK center horn and use that.


Dave Brown arrow shafts will flex cause the 4-40 rods to weaken and fail. This is the place for a CF titanium fitting above all other places....Many people have lost planes not installing this MK device properly or using it properly.


It works very well and is a good product...but has to be used properly. I don't like cables but many people think that switching the MK to cable control inside the fuse is the way to go...


I have a better solution that is lighter and much more positive than the MK...It takes about 3 times the work to build and install. Its not really any cheaper but I feel its a better design.

The MK is probably next on my list of choices... It super simple to install has a bit of a $ tag but is defiantly superior in all other ways to the Dave Brown Arrow shaft. Just because they are black don't mean they are CF...they are fiberglass and flex a ton.....You need a good support system to keep them from moving.....

This is my opinion and other have theirs also....but it is worth exactly what you paid for it.....the advice that is!...LOL


Troy Newman

THANKS TROY, WHAT IS YOUR ALTERNATIVE TO THE MK BELL CRANK? PLEASE TELL US.

I have just started using RC model enterprizes control horns. They are anadized purple and are really nice and simple. Check 'em out

Andrew Jesky

I'm looking at the Central Hobbies web site and see three different sizes for the MK control horns:

http://www.centralhobbies.com/miscel...cntrlhrn2.html

Can anyone tell me which sizes are correct for ailerons, elevators, rudder, respectively? Thanks.
--Derek

Hi Troy,

Many thanks for that very informative reply!!

I too believe the MK ball-raced clevis's and connector's are the best money can buy. Some servos buzz even if there's the slightest bit of binding in the control linkage. Because MK features bearings, I would think this should eliminate servo buzzing.

>>I use the 2mm version with 2-56 and will drill them out for 4-40 and I have used the 2.5mm for 4-40 thread.<<

Sorry, but I lost you here. Why do you drill them?

Your other reply (post # 12) got my attention. What did these people do wrong to have lost their plane when they installed and/or used the MK bellcrank improperly? From reading your reply, I got the impression the MK bellcrank wouldn't be your first choice. You said you had a better solution than using a bellcrank; I too would like to hear what that better solution is?

Also, why don't you like pull-pull cables for the elevator?

I'm currently flying a Hanger 9 "Aresti 40" sport-pattern plane and have been practicing pattern maneuvers for about six months now. I swore when I was installing those flimsy wood dowels with 2-56 rods supplied in the kit I would install better control linkage in the next plane I build. I'm looking at buying the CA Models "Widebody 60" for my next plane and want to do the control linkage right this time!


Don

EDIT: Deleted......... Got Help in the 3D forum.

Servo buzzing can be caused by binding in the linkage....What you will notice as you get a totally slop free linkage sometimes it will still have some buzzing especially with digitals....It depends on the servo and the the size of the control surface....The weight of the Aileron can also be an issue...Since old Newton is acting on the control surface this force is creating a reaction force in the servo...hence the power usage....
This is only a issue on very large control surfaces...not the pattern ones usually have....Some slight buzzing can be possible...but this does't happen during flight there are many other forces at work up there.


Why do you drill them? on the 2mm links....the reason is these will work as they stand on 2-56 threads....the 2mm hole is a touch small to jam the 4-40 into and start cutting a thread...The clevis part is a strong nylon or plastic type material like most connectors....So I did them out slightly and run tap down them partway. The tap going down say 1/2 way allows for the start of the threads...and the rest to be cut by the threads so its a tight fit...If you tap the entire connector the clevis will turn on the rod like its a nut....When you take you servo out of clevis off to work on something the clevis will turn and loose its adjustment.


Cables......I'm not a fan of cables. They seem to have benefits but I just have not liked them on the elevator...In principle they have some advantages....Weight, and flexibility of adjusting all 4 travels....L-UP, Ldown, R-up, RDown all independently.....


My hang up is I guess the cable will stretch a little over time and you will have to adjust the tension....I use 30lb test nylon coated steel fishing line for cable....Don't have issues with the cables breaking....but it will stretch a touch...and if there gets any slop you will feel it. I just don't like to build setups that require maintenance in the future....Yes I use cables on the rudder....so whats my problem....just never really been sold on them for the elevator........Also they look crappy coming out of the fuse....again they are more functional than pretty...just not my cup of tea.


OK now for my Elevator pushrods.......I'm working on a comparison between the MK, Cables, and the CF pushrods I use....Its in a word document right now...and not edited....I will post it under a separate topic like Elevator control linkages....or something like that.....probably tonight.....got some stuff to do today....but should get it done.....\


Troy

All right Troy, you've got us all on pins and needles here waiting to hear about your new elevator control system.

Keith

what engine are you using on your diablo 2000?
is this a good plane for pattern and 3d??
want to put a gas engine on it? what size is best? a 3w24? or larger?