LDM

My Feedback: (15)

Your going to find that with etracts the accuracy of the eletric board is key to the lack of slop in the gear. I have found no association in cost to the quality of the board used. The second factor is the drive screw, on the smaller units this is the first thing to go because its easily bent under pressure if the strrutt does not do its job. The third factor is the motor and its ability to lift the wheels you choose to use.
In my earlier purchases I was useing a barnd called changesun, and they would not lift the wheels needed for the planes they were specked for use.
Now other issues exist in the USA brands, Robarts being the most disappointing of the bunch ,,,why ? Because most of the componants are being made for them. The reports in threads in RCU and RCG are that the eletronic drive shaft is not attached to the frame in any manner suitable for durability. While the drive shafts used are powerful the biggest complaint is the assembly and that is a result of robart having to use parts outside there own facility and then not testing constant use or simply failing to test normal use under load.
Horison has the best record for planes 60 size and under /12lbs and under . BUt most of the Horizon retracts can be found in knock offs similar in performance without the warranty at 1/2 the cost.
For models under 15 lbs , the FMS brand sold speficially for FMS EPO warbirds in 1400 and 1700mm sizes are very very reliable and cost effective especially if you need gear for Top Flight similar size warbirds.
Theres another brand ( name escapes me ) but there sold by Park RC website and also at retail in Orlando at Graves RC Hobbies, they state they are rated for birds at 24 lbs and higher. I know for a fact they are not field proven and some of the original distributors stopped selling them because the componants are not consistant in operation.
You may say with all the unknowns why bother ?? well with the exception of Sierra , swithing to eletric for me was a no bariner , super easy plug and play and with careful selection you can achieve problem free set up with your retracts

chistech

I've found with a lot of retracts, especially the electric and mechanical, a fair amount of problems are because of improper installation. I know that the retract mounting rails have to be perfect with the electric retracts or operational issues arise and people blame it on the retract. For years guys could never get the proper amount of throw on the pushrods for the mechanicals and they would complain that the retracts didn't lock up. A fair amount of time it's the people factor that causes issues.

raptureboy

Yep, same with air gear. If your not willing to do the work needed for proper setup and maintenance you are going to have issues. I am thinking of getting a corsair next so all these leads on the electrics will help. Thanks.

ululi1970

A little cautionary note on the HK retracts: Make SURE you apply thread lock to the grub screws that hold the 5mm pin to the trunnion. The grub screws are located inside the metal hinges of the trunnions. I did not do that and almost lost both wheels and struts on the first flight...
So typical of HK...

Tony Iannucelli

My Feedback: (193)

I respectfully disagree about using thread lock on the grub screws. The inserts are brass, and even blue Loctite will bond to them. Not a good idea if you happen to tweak the strut and can't get it out. Instead of Loctite use TWO grub screws on each side. The second one, 3x3, will lock the first one in good enough. I have five sets flying, none came loose. Just an alternative.

ululi1970

Did not think about that. Well, the deed is done. I guess they are cheap enough that replacing the whole thing is not too expensive.

spaceworm

I don't know what other materials are involved, but heat from a soldering iron will usually soften the hold Loctitie has on screws and/or nuts. But, take care if plastics or other parts are in the thermal loop.

Sincerely, Richard

chistech

This is exactly what I've been doing for a couple years now with all brands that have those trunnion grub screws. I learned by using Blue loctite and finding that the one time I needed to remove the screws, the brass came out with them. Heat didn't help much on the other either. I have over 11 sets of gear done this way without one lost or loose strut. I put many hours into my Tangiku Shinden Kai and I'm using HK units with modified VQ struts. I even have the gear closing the inner doors mechanically without issue. I have used and tested the HK units enough to trust them to this plane and my hours spent. One modification to the original design was to cut the outer door and have the lower section move with the tire as per the full scale. No bent gear doors as I experienced with my P47 built similar to this plane.

raptureboy

Nice looking plane. I used these hinges on my P-47 main gear and adapted the set for a nose gear to use on the tail wheel. very simple to use. http://www.sonictronics.com/xcart/pr...cat=378&page=1

LDM

My Feedback: (15)

Nice link , great stuff on that site ! I am working on an ESM corsair and need some flap hindges and may use those new Carbon Fiber Hindges !!

I just received new retracts for a 60 to 90 size plane from HK , along with struts, great value for the cost

chistech

With the Shinden Kai I was trying to represent the actual hinging and closing system of the inner door. First picture is the full scale prototype, the second is my 55" model. With the smaller planes there sometimes isn't enough room for the available hinging systems also. Not sure how big the sonictronic units are. Like I posted earlier, the HK units are able to close a metal oleo strut, scale wheels, and inner gear doors without any issue. I have found no other similar type retracts to be any better than the HK ones I'm using. When they were first available I did have one or two ship DOA and one or two fail, but haven't had that happen now in a couple years.

raptureboy

Very cool, what model number on the retracts. I too have tried several brands and gave up as they all could not lift the gear with 4" wheels even on a 2 cell lipo. The sonic hinges are quite small and fit in my TF 60 size p-47 Did you scratch build the Kai or is it a kit?

LDM

My Feedback: (15)

Servoless Retract with Metal Trunion 44mm x 41mm Mount (2pcs) 2 US$15.25 IN STOCK
Alloy Oleo Strut 115mm Straight Mains for 40~60 Class 2pc 2 US$14.15 IN STOCK
these are the ones
These are the ones I just purchased for a 60 size model but I will be useing light weight wheels

chistech

I use the 44mmx 41mm mount, part #225000018. $16 for a pair right now in the US warehouse too. They are the metal trunnion with 5mm pin. Buy a 5mm drill for your oleos so there is no play when installing them on the pins.

The Kai is a Tettra sold kit marketed only in Japan. Super nice kit that is pretty much a hybrid of the old Marutaka/Royal kits. No where near all the extra wood to sand and updated with super nice heavy plastic parts. This plane flies incredibly well also. Plans look like duplicates of the Marutaka "blueprints" also. You can get them from a couple shops in Japan for about $210 shipped to your door. Some guys might find that expensive for a .50fs size plane kit, but I'm a builder and they are some of the best I've seen. They can be built quickly if you build to the plans with strip ailerons and open bay/film covering. Mine is highly kit bashed and all glass/paint finish. I am also in touch with the designer and owner of the manufacturing company, Tangiku, and he will correspond with me when I send him emails. I have another Japanese friend that I copy on those emails and he translates for both of us!

The HK units are perfect for these Tangiku kits.

chistech

Bingo!

raptureboy

Thanks guys. Good luck on that maiden.

radfordc

My Feedback: (14)

These are a little big for a 60 size model but work great for something in the 90-120 size.

http://www.hobbyking.com/hobbyking/s..._10mm_Pin.html

You can see me "testing" them here. This is the third time I've knocked them out of the wing and no damage yet.

Tluu

My Feedback: (85)

These retracts are great. I have 2 set in my 55cc mustang and they are still going strong with more then 50 flights on them.

rgburrill

Inexpensive electric retracts? How about mechanical retracts with a retract servo? Same thing.

radfordc

My Feedback: (14)

Yep...same thing, only 10 times harder to install and adjust.

stegl

Sort of a thing of the past. The plug and use electric retracts appear to be the way things are going. I recall couple of years ago on a jet forum that no , but definite no to electrics on turbine jets . When I suggested that electrics will happen ; I got" boiled in oil" on even suggesting that one. Well lo and behold one
of our very knowledgeable jet flyers converted one of his aircraft to electric and then you should have hear the naysayers change their tune. if it was ok for so and so then it must be ok... Change sometimes is slow but it happens.

irocbsa

My Feedback: (12)

Wow. How is it that entire airframe isn't in pieces after that one?

raptureboy

He didn't show the rest of the pictures

radfordc

My Feedback: (14)

Well, it is rebuildable at least.

raptureboy

Strong like Russian woman LOL