RC Slope Soaring in Hong Kong

今日係飛鵝山見到阿 Kong﹐佢交左兩隻燒左既 Hitec 125MG servo 俾我. 相片中既 servo #2 同 #3 就係兩隻 servo 燒完之後個樣
http://yclui.rchomepage.com/Hitec_wing_ ... _burnt.htm

阿 Kong 話佢裝左呢兩隻 wing servo 係隻新機隻翼度﹐條尾就用 Hitec 81MG。 飛左一個 flight 無事﹐平安降落。再開接收時(發射熄左)就聽到個BB既響聲好快變細﹐跟著就聞到一陣囉味。兩隻 wing servo 就咁齊齊玩完。但係控條尾個兩隻 81MG 就無事﹐佢無好似 Stanley 咁用 5 舊接收電﹐只係用 4 舊。咁都燒servo, 你都咪話唔恐怖。

綜合 Stanley 同阿 Kong 既經驗﹐Hitec wing servo 肯定有質量控制問題。好彩有個共通點就係三隻有問題既 servo 都好早期就瓜﹐所以如果真係要用 Hitec wing servo﹐ 一定要裝落機前叫個 servo 玩舉重幾個鐘﹐如果個 servo 仲識郁﹐應該都會幾穩陣呱 .

剛剛收到挪威機手 Jojo 既電郵﹐話D Hitec wing servo 齒輪好唔掂。以下係佢同 Hitec 既對話﹕http://www.hitecrcd.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=3;t=000348

Y.C.,我燒個隻5125MG正是如Jojo所說，熱到飛起burned，回中位又大，一看裏面的齒輪間值不堪入目，真係唔明白點解美國咁贊Hitec好，仲話你係唔係JR既奸細，係網上唱衰Hitec，本來念注加把口，鬧返佢地，但最後都係忍注條氣。而家又有人挺身而出指証Hitec真是大快人心！我唔知以前Hitec 125 Servos怎麼樣，好明顯Hitec最近一批125或5125金屬牙係有好大問題。

YC，你D DS161 試未？OK嗎？

我個兩隻未試. CM 隻 Spider X 翼入面裝左 4 隻 JR DS161 wing servo. 上星期日飛個陣曾經試過對 flap 落左黎唔識返上去, 但降落後撿查又無事﹐跟著個問題就無再出現。依家都唔肯定關唔關隻 servo 事。

上星期我收到 JR 美國代理 Horizon Hobby 既電郵,確定 JR DS161 (或 168) 係用 Hitec 125MG / 5125MG 既外殼﹐servo 臂同齒輪組﹐但係摩打同控制線路就唔同。我估 JR 既電子部份會好D﹐但係D齒輪都會一樣咁唔掂。

YC, 咁D servo齒那處有得賣？最好可淨買膠隻啦，因為通常係隻膠齒出事多

我少玩滑翔機，但我想會玩多Ｄ，因在香港冇咩地方玩power機 n 直升機啦，玩滑翔機點都多D地方同方面Ｄ

話時話Ｄ servo 齒你會幾耐換一次？
我家通常每飛80次(直升機計)就換所有的膠齒，我都係以安全為上所以咁做，在滑翔機有同樣須要嗎？

Hitec wing servo D 齒輪網上好多度地方都可以買到﹐不過好似一買就要一套﹐仲好鬼貴﹐要近 HK$200! 即係一個新 servo 價既六成﹗

我由以前玩 power 機﹐直昇機到依家玩滑翔機都未試過因為 servo 齒輪自然損耗而更換 ﹐通常都係因為碰撞而導致 servo 掃牙﹐所以我都唔知滑翔機既 servo 齒輪可以頂 得幾耐。我隻 Shooting Star 已經飛左超過兩年﹐翼入面個兩隻 Hitec 125MG 都唔覺有也虛位。我估等D虛位較明顯至換都未遲。

尋晚我上 Hitec 個網頁舉報燒 servo 事件﹐好快已經得到廠方回覆 http://www.hitecrcd.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=3;t=000415 佢地都係賴話D servo 受力過大所致。但係佢地又話D servo 應該可以頂幾分鐘﹐唔會幾秒鐘就燒﹐我睇佢隻錶一定係快過正常既幾十倍。

The digital servo (MG5125) that was burned while I was setting up my Trinity wasn't stalled at all! I turned on the system with all the servos in the neutral positions. The servo started to develop vibration after about 20s when the system was on. Then, only one or two seconds later it died with smoke of hell!
The other digital servo on board the Trinity in Shek O was also developed some funny vibration only 20s in flight. After I have recovered the plane and gone back home, I checked the servo again (still powered by 5 cells battery), I found that it didn't move at all (looked like it was jammed but nothing was obstructing its movement anyway), and it produced a very strange loud mechanical voice. I immediately switched off the power. Few days later when I had free time, I modified the power system to 4 cells and switched on the system, then surprisingly the digital servo functioned again and it seemed back to normal. I carefully checked it again and again, and it looked completely ok! Anyway, I have no confident on this servo anymore and I decided to replace it with an analog one (MG125) - well, I have no other choice for ultra slim servo for the time being although I would say I am completely lack of confident on all Hitec servos!

大約半年前﹐Hitec 將D wing servo 劈價近 20%, 唔通佢地係將貨就價 ?

Stanley, 今個星期六去唔去石澳呀﹖如果去就記住帶個隻識跳舞既 5125MG 同掃左牙既 125MG 出黎俾我。話時話隻 Trinity 個日只係慢速 spin 落去呢樹叢度﹐隻 125MG 點會掃牙架 ?

如果得就最好帶埋你隻識唱歌既 banana 出黎﹐拍番段 video 擺上網應該幾得意。

剛剛係 Glider King
http://www.gliderking.com/modules.php?op=modload&name=XForum&file=viewthread&tid=886 睇到呢個報告。睇黎同 Stanley﹐阿 Kong 有一樣遭遇既仲有好多人。共通點都係隻 servo 好早期就瓜,唔會捱得超過一個 flight.


I bought four digital 5125's for my new Opus W and had a problem(s). As soon as I plugged one servo into the receiver for testing the servo was very jittery and would not center. I was able to return the servo with out any problem to my local hobby shop for an exchange (lucky for me I didn't' glue them in yet). However, I noticed after I glued all four servos in (including the replacement servo) one was very noisy as if it was having difficulty finding a position without any tension on the arm. It was always making a humming sound no matter what.

First flight went smooth with out any apparent problems. All servos were trimmed and operating normal.

Second flight: Big Problem, My plane started flying very weird, so I brought it around for a hard landing that was beyond my control. The noisy servo, which was in my flap bay had malfunctioned. It was so toasted that the servo motor sticker and housing where bubbling from the heat caused by the malfunction. It damaged my top wing skin with an ugly burn mark where it was glued (which looks like a cigar burn mark). Other damages occurred to the wing as a result from the hard landing.

Although these are first set of Digital's I owned, I don't want to sound like I am criticizing 5125 servos but for what it's worth I like the performance and toque these little servos have for the money. They have no gear slop that I can see and center every time I turn my radio on.

I sent Hitec a letter in detail explaining the situation along with the servo back for inspection. It took almost four weeks to get a verdict but here it is:

12/15/03

Dear Orlando,

I am sorry that we have had your servo so long. After looking at it with the technician and reading your description, I can only assume the motor went out. How this happened is very difficult to determine. I told the tech to replace the servo and I am sending you another one as compensation. Though I don't normally do this, I felt it was required this time. The 5125 servos have been very successful for us and are gaining acceptance in the soaring community due to slim packaging and strength. I think the one you had was a fluke and the rest should serve you well.

Regards,
Tony Ohm
Service Manager
Hitec RCD USA, Inc.
Ph: 858-748-8440
Fax: 858-859-2618


If anyone has had similar problems please post it for our fellow flying buddies who might be in the market. I hope it was a streak of bad luck with the servos because I just put the new servo back in and I am going flying today.

Regards

Orlando
12/21/03

In fact, I had similar jitter and failure to centre problems in one of my 81MG servo after the initial setup. It produced very loud mechanical sound and become very hot. I had no alternative but to removed it with extreme difficulty.

Kong[color=yellow][/color][color=yellow][/color]

I think Hitec knew about the problem as there are so many complains recently. From what I see is they just deny it for the sake of corporate image. Even though they know it is their fault probably in the design or in the manufacturing process, they just hope that that problem will fade away. I am sure if the return rate is getting higher, there will be more damage to their image rather then admitting it now. I think they should admit the fault and recall all the unreliable servos. You know flying a sailplane is just like driving a car, if an item on board is malfunction, the consequence can be VERY serious!

It seem to have a lot complains about Hitec servos. What happen to their new design? In the pervious decay, their servos were cheap & strong. Almost all servos in my F3F sailplanes are HS-85MG. In recent 2 years, I start to fly F3D, I also use HS-85MG in the wing. I crash more than 10 F3D planes. At 2-3 times, the speed during crash were over 200Km/h. These 2 wing servos still survive without damage a single gear (total 10 F3D). I think Hitec should play more attention to thier new products.

今期的 March Q&EFI page 62 至 64 頁，講到有關 Hitec 同 Volz servo 用 5 粒電既時候出現唔正常現像。話原因係 D 大容量差電蕊、係差完之後，電壓可以高至 7.5V。超出 D servo 既 6V 極限。 要等電壓回落之後， D servo 先回復正常。
Stanley 同其他師兄既 servo 問題， 亦有可能同電壓有關！

Stanley, 上星期六你隻 Trinity 個兩隻 Hitec 125MG flap servo 開完 butterfly 後就齊齊罷工﹐搵到原因未呀 ? 我都仲係懷疑你個發射或接收俾去 flap channel 既 pulse width 過大或過細﹐普通 servo 只會去到極限就停﹐ Hitec 有可能會黐線。但我係屋企試過用 JR 發射將 travel adjust 較到最大150% 就無事﹐所以好似又唔關事。真古怪。

講你都唔信 Hitec 啲屎野又嚟!
唉!我星期六個日降落隻大蕉時用 Butterfly 收放自如,落地時隻機非常漫和平穩,睇落隻機會無事,點知原來两隻flap嘅servos都掃咗牙!喺金屬呀喎!
你自己睇睇 Hitec 死屎牙!

Hitec 定喺同我有仇,真喺比佢玩死。
各位機除咗 Hitec 啲 Wing servo 外仲有什麼其他選擇呢?

Stanley, 我都定你肉赤﹐又有D心寒﹐呢 Hitec servo 好似紙紮咁弱﹐我都唔係好敢再用。其它牌子既 10mm servo 只有一個選擇﹐就係 Volz Wing Maxx http://www.volz-servos.com/english/servos/wingmaxx_eng.html 我曾經買過兩隻 Volz ﹐不過唔係 Wing Maxx﹐而係 Micro Maxx ﹐發覺D虛位大到得人驚﹐同D美國佬講﹐竟然俾佢地話我小題大做﹐仲 email 左呢張相俾我

警告我唔好中傷 Volz,如果唔係 Volz 老闆隻狗就會對付我﹐真誇張﹗所以我對 Volz 既印象係麻嘛。Volz servo 仲非常貴﹐所以真係要唸過。

好可惜，我地最大果隻都只係"芝麻" . . .

Volz 唔掂，咁 JR 牙掂唔掂？
睇落 JR 牙同 Hitec 一樣喎。

Just check Hitec site to see whether I can buy the 125MG metal gear. They call their gear
"unbreakable". What's a joke! I think they should be liable for their claim!!!
http://www.hitecrcd.com/Servos/hs125.htm
Anyway, the gear is too expansive, cost at least US$26 each - stupid money sucker!!

I guess I will give them up all and never touch Hitec product again.

Stanley, 老實說我都有些不能相信，HiTec 真的是這麼差劣? 我還有四隻 5125MG 未用，難道真的只可用來推 rudder?

記得早些時 JR 有隻新出的 digital servo 在直昇機上有 lock up 現像，Horizon (JR 在美國的 distributor) 立即宣佈回收修改，並建議不應用在直昇機上，相對於 Hitec 回避問題，JR 就顯得負責任得多。

5125MG 的 servo 牙灰灰色的，像是鋁合金之類，若然則應不能承受太大衝力，但都不應該這麼易就掃 (加上它有膠牙保護 )，我有點懷疑質量控制有問題，Stanley, servo 上應有生產日子，壞 servo 是否同期生產?

我想 10mm servo 中應以 Volz 的 Wing Maxx HP (servo 殼鍍 chorm 那隻)最好，它的輸出牙是鋼造，我裝了四隻在 NewSting 上，有點虛位，但應可接受。

我上次由 Tun 買左4隻 Hitec HS125，打算裝入隻 Spider-X 度用。 但係睇左好多 Hitec 壞 servo 既報告之後，決定幫呢幾隻 servo 做舉重測試。
我將 2粒 Shooting Star 既 ballast 掛左係支 servo-arm 最出面既洞。一開始己經發覺佢行得唔順、行程短、又冇力。 唔知係唔係／一總重7安士既 ballast 係過多？但係減少到1粒 ballast 都係一樣

重有3隻舉1粒 ballast 就舉左拾幾分鐘都冇事。

到底係我用兩粒 ballast 係過重，定係個 servo 原本就係壞既呢

我地係用家﹐依家好似變左廠家﹐唔知可唔可以同 Hitec claim 番人工呢 ? 用 4 舊電時, Hitec 125MG 既扭力係 3.0 kgcm, 即係話﹐如果舊重量掛係距離 servo 臂軸心 1cm 個窿既話﹐隻 servo 可以吊得起 3 kg (仲重過你隻 New Sting), 如果掛出多 1cm, 可以吊起既重量就減半 (1.5 kg), 如此類推。我試過搵 Stanley 隻曾經有問題既 5125MG 玩舉重﹐我用 Elita 個條 1kg ballast, 掛係最入個窿同第二入個窿都無問題。用手出力扭隻 servo﹐扭到手指痛隻 servo 都係扯 0.7A 電﹐睇落好正常。如果有問題既話﹐建議寄返 Hitec, 要求更換。辦法見 http://www.hitecrcd.com/Support/ServiceAndRepairSFS.htm