銅燒焊車！？會是時空錯置嗎？/mhc
銅燒焊車之所以美，很重要的一項要素是套管部分(Lug)的做工；英文叫她為vintage lugged frame其來有至。比較有名的Lug如Hetchins (England), Nervex (France)或是Prugnat (France)。不過這些都是歐洲貨，不知道早期台灣有沒有比較能代表台灣的handcut lug，如果有我建議採用；不過我想機會不大，因為如此耗工的事應該早已不再商業化了，要找1組都難，何況要10幾組ㄋ；
另外還有個人角度問題需要考慮；頭管坐管上管長度更因人而異。
如果沒有現成的，那能否考慮選用『素lug』 (blank lug，原胚Lug未做任何切割)，然後我們想辦法把山羊頭刻弄上去(這可要問這方面的專家阿鎰有沒有辦法做到了 )，也把個人姓名及山羊編號刻印上去，這樣比較有個人風格，畢竟單車喜好是非常個人話的東東，如此這樣那才能將『她』供奉在客廳牆上每日朝拜。
至於彩裝是不是請0027及ak比較具藝術氣息的設計一下，來個ArtDeco彩裝。
如何切割屬於自己的套管(Lug) /mhc
第一我中打很慢，第二國學底子差，可能會失焦，所以我就不強加翻譯了；就我看到的簡單敘述如下；
(1)先取得素胚(blank lug)，作者自述於1967自英國帶回一組管材(Reynolds tubing)及素胚(Nervex blank lug)(這裡我想必須說明一下什麼是素胚，一般我們在學生車看到的有尖尖的伸向後方，這已經加工過不是素胚；剛出廠的齊口才是素胚)。完整的一組Lug包含：頭管上下、座館、五通、前叉冠座及前後叉勾爪共七件，前三項有角度的考量。
(2)設計圖樣，簡單的圖樣較容易切割，一般市面較喜歡採用撲克牌牌上的一些圖樣去做變化；較複雜的圖樣則較耗時，有可能碰上無法進行下去的窘境而必須加以修正；有些人會利用焊接來加長Lug的作業面積以設計較美觀的圖樣，這純粹是為了美觀，對增加強度無補。
(3)開始切割，作者採用電鑽及鑚石鋸子(jeweler’s saw，是銼刀嗎？)來切割；盡可能先將不要的部位用電鑽去除，然後再利用鋸子完成其他部分。
後話：以現在雷射雕刻的技術，也許不會那麼難切割了吧；不過好像少了什麼來的。
最後我想以作者的一段話來結束(還是豆芽)
I liken a well-designed lugged frame to a good engraved English shotgun. It doesn't shoot any better than a plain shotgun, but it is pretty and shows the builder's care in making it.
也許會花三年五年來完成一件自己的vantage lugged frame吧！也許十年吧！也許『她』只是一場夢ㄚ！但『她』維繫著我的熱情不滅，這樣就好了。（原文置於本章最後）
說到LUG /小帽
好的 LUG 帶你上天堂
不好的 LUG 帶你住套房(騎到腰酸背痛住醫院套房)
角度確實是個大問題，也請參考鳥教練的兩篇筆記
鋼管車拉格筆記--上
鋼管車拉格筆記--下
那個 853 銅鑼燒什麼的，也會這樣迷人嗎？
re:LUG /ak
你沒講我都不知...，真是大學問，Old school is real school !
Re：LUG /牆頭草
為什麼我騎了這麼多年的LUG車架都沒人注意呢！
我在猜啦，原提議者應該不是要訂製MHC講的HANGCUT LUG車架啦，而且是素LUG固定車架角度的車架，當然我是樂觀其成啦！
以前跟朋友在講LUG車架時，也曾提到HANGCUT LUG這話題，當時不成熟的結論是：先跟台灣車架廠商溝通好並且確認各部位端口接口管徑規格後(或直接能拿素LUG)，到印尼或泰國等手工技藝先進的國家找位工藝家設計製造。
但我有疑問啦，前題是有辦法拿到 & 切割出我們要的LUG形狀及角度，且有廠商願意幫我們燒銲 ：
1.越薄的LUG燒銲出來的車架會越水，不論厚與薄強度要怎麼確認呢？
2.LUG角度有人會訂嗎？車架製造圖怎麼繪製？
3.成品試車結果可能會超出您的期望！
4.要匹配這車架的零組件要到那買？
5.Money啦！
要是真能生產出HANGCUT LUG車架，不管其車架是否符合騎乘條件，AK請注意這是一不錯商機！
小弟無知不成熟的想法，請各位大大指教！也請原提議者朝著大家所需努力吧！
Re：LUG /阿謚
最近我問了我客戶,他是這個產業老前輩,曾經幹過上市公司的總經理,我問他lug是如何製造,他告訴我的答案,是比我想像中工程浩大多了,如bb五通那個lug,是先拿一塊鑽好五個洞碳鋼加熱用沖床慢慢鍛造出來,當然不是用一台沖床就造的出來,不像外國那些阿ㄉㄛ用管材接一接那些lug,至於車架製造圖怎麼繪製,我想對於學過機械製圖的人,應該不是很困難,.LUG角度我想可以參考現成車架,或如美利達它都會出一本它現有車架的角度圖,至於商機我想這個市場太小,不然外國那些手工車的工廠好像都是小小規模不大,最後我想有時間的話可以自己做一台車架玩玩,至於強度應該比是售車強,不過重量我想一定比較重而且重多了.
無聊看看 LUG/ PPT
之一
之二
罪惡淵藪/ 黑羊
LUG 啊 LUG
多少罪惡以汝之名行之!
接續HANDCUT LUGS
How Do You Build an Ultimate Collector's Bicycle?
The Man Who Should Know—Framebuilder Art Stump—Shares His Insights by A.D. Stump
The following article appeasilver in the August 1980 issue of Bicycling! magazine. Reprinted without permission.
As one who specializes in collector's bicycles, I keep an eye out for signs of public interest in the kind of work I do.
Thus, it was with great interest that I read some time back an article about the then-new Reynolds 753 tubing. The author said that since an even section frame joint is especially necessary with that tubing, we may see a revival of handcut lugs.
The need for uniform thickness at the frame joint is important because overheating of the thing section tubing can occur if the lugs are on the heavy side.
Thinning the lug and cutting it to make an attractive design has two technical benefits.
First, it lightens the lug and allows brazing or silver soldering of the joint to be done at a lower temperature, with less danger of overheating the thin-walled tube.
Second, the flow of the silver solder can be seen more easily with a design in the lug that gives a few "windows" to see into the joint.
I believe a lugged frame is stronger than a lugless frame. The lug offers a joint that in effect grabs another handful of tubing and spreads the stress on the frame over a greater area. The lugless frame, made with thin-walled tubes, can present a risk with the need for a heavy fillet radius to make a strong joint. And the low temperature solders I prefer do not build up a fillet or heavy radius at the joint.
Brass or bronze rod can be built up into a fillet joint, depending on the skill of the builder, but it takes quite a bit more heat. And it needs to be filed into a uniform-radius bend for pleasing appearance.
Filing Difficult
Brass or bronze is hard to file, and it takes a good sharp file to cut it. The problem of thinning the tube wall is ever present. The tendency to "guide" off the tube at the start of the fillet is difficult to avoid, as the sharp file will bite into the tube to get the appearance of a continuous joint. I don't condemn all lugless frames. With heavy-walled tubing, they are fine. The heavy wall gives a needed safety margin. I have seen lugless tandem frames that were noticeably undercut or thinned when the fillet had been filed, either by hand or with power-driven rotary-file or polishing tools.
Like a Shotgun
I have always been partial to well-built bicycles with handcut lugs. I liken a well-designed lugged frame to a good engraved English shotgun. It doesn't shoot any better than a plain shotgun, but it is pretty and shows the builder's care in making it.
Because of high labor costs, few builders now make frames with handcut lugs. A decade ago, I asked Bill Hurlow to build such a frame for me. Even back then, he said the cost of his time would make it impossible. How much time? He told me he could cut a set of lugs in a day. Bill must work very quickly or have extra long days.
My personal interest in handcut lugs goes back many years. On my first bicycling trip to England in 1937, I looked over the frames built by the classic builders of that time: Claude Butler, Bates, and Hetchins, to name a few. I also admisilver the Thanet on display in London's South Kensington Museum; that bike had been sectioned to show the joining of the Reynolds tubes.
On my next trip in 1964, I ordesilver a Gillott frame with fleur-de-lis lugs. Ron Cooper, who was learning his trade at the Gillott shop then, built my bike.
I decided to try building my own handcut lugged frame. In 1967, I came back from a third trip to England armed with a set of tubing and Nervex blank lugs.
That first frame took me a long time; during my spare time I built tooling and jigs to construct it. I adapted my lug design from the Gillott and Hetchins designs, and my initials in the bottom of the head lug.
The variety of patterns that can be worked into the lugs, fork crown and bottom bracket is limited only by the metal in the lug and the builder's resources. You can even heli-arc weld extensions to the lugs, easily overcoming one of these limitations. (But the welding must be done with a mild steel rod; the stainless steel rods which welders prefer to use leave hard spots, which dull my files and jeweler's saw blades.)
Rare Nervex Lugs
The Nervex lugs, which adapt themselves to detailing, are now very rare. My personal supply of a few sets comes from my visits to England.
Prugnat long-point lugs can be made more interesting with drilling, counter-sinking and thinning the edges. They don't give much area to work with, and the common playing card designs (spades, hearts, clubs, and diamonds) have been, for lack of a better word, overworked.
I often use library books on monograms and heraldry as sources for interesting designs. Also, an intriguing design can be found simply by following the outside contours of the lug and adding a few leaves or scrolls in the corners.
Added Strength
Some builders, in quest of more ornate lugwork, overlay a sleeve that is brazed on for decoration only. I prefer to weld the sleeve to the lug or fork crown; this makes it a structural part of the frame, not just a decorative add-on. Most fork crowns don't have enough metal to make a design, so I prefer to weld the extension to the crown. This forms a socket for the fork blade and adds to the strength of the joint.
I encourage my customers to design their own lugs. This gives them an added interest in the frame, and their imaginations have produced some fine designs.
Once I executed a very simple frame for a Chinese lad who produced the design himself. His name was Yale Yee, and his initials blended beautifully with the Prugnat lugs used.
When I discussed a frame with another customer, I jokingly offesilver to do a Biblical scene. He took me up on it, and we ended up with various types of crosses, the dove of peace, alpha and omega, and Jesus in the shape of the fish in sterling silver.
Another customer, artist Vivian Nickas, supplied a neat design including her name in the bottom of the head lug and her initials in sever of the other lugs.
The finish of such a frame is critical; if it is less than excellent, the work in the lugs will be lost. Hence I polish all the tubes and lugs before brazing. Power tools generally do more harm than good, and I have to do most of this work by hand. I outline the lugs with gold leaf. It looks rich and takes more work than bronze base paint, but I think it is worth the extra cost and effort.
The finish I used on my first frame was black chrome, and it has an unexpected result. Plating detracts from, rather than enhances, the surface appearance. It magnifies the scratches and rough surfaces, so the frame must be especially scratch-free and brightly polished prior to plating.
Lug Cutting
I begin my lugwork by silverucing the thickness of the lug to around one millimeter. Many lugs vary in thickness, and a too-thick lug is difficult to work with a jeweler's saw. After thinning, I rough polish to get an even surface on which to lay out the design with a layout dye such as Dykem or a thin coat of lacquer. Another method is to draw the design on tracing paper and cement it on the lug. I also scribe centerlines and guidelines that help keep the design symmetrical and balanced.
I drill as much of the metal to be removed as possible, since it's easier to use the drill than the jeweler's saw. And when I use the saw, I use a big a blade as possible. Bigger blades last longer and break less easily. (My favorite ones are made by Hurkeles of Germany.) It takes a lot of care to cut radii, since it's all too easy to undercut the design — especially as the thickness and width of the cut varies as you work around the lug section. I often have trouble finding room to pass the saw blade through the lug, cut the design I want, and avoid having the blade cut or nick other parts of the lug. I use small files to blend the design, smooth and thin the edges.
Cutting fancy lugs is neither easy nor difficult; much depends on how far you want to go with them. Simple designs can be quite effective.
Builders who make high-quality frames do it because they like good bikes and enjoy the work. The financial reward is certainly modest. Framebuilders young and old, here and in England, agree that it is a difficult way to make a living. Most of us could earn much more money applying our metalworking skills to other trades.
Most framebuilders, whether they use handcut lugs or not, make a good product and don't mind charging high prices for it. That's how it should be.
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