I have melted a few stems out. It's not as bad as it sounds. The melting point of Al is lower than the heat-treat temp of steel so it's relatively safe. Except on small frames, I've been able to do it without even hurting the paint, by wrapping the crown in wet rags and getting the job done quickly. And it's a tiny fraction of the work involved with Dale's surgical method - most people would rather put a carbon fork on a Confente before resorting to that!
You'll need an oxy-acetylene, oxy-mapp, oxy-propane rig or the like - air torches may get hot enough (I'm not sure) but it'll take forever. The trick is to soak as much heat in as fast as you can; use your biggest torch tip (a "rosebud" is great) and crank it up. Hold the fork right side up so convection takes the heat away from the crown, until right before the Al melts, then turn it upside down so the melt runs out the top of the steerer. Bang on it a coupla times to knock the last droplets out.
I always had a 7/8" reamer handy so I always ran that through after. I don't remember how necessary it is. If you don't have one, here's a cool tool everyone should have: I call it a "windup". It's like a sanding drum but infinitely adjustable for diameter, so you can make an accurately-sized drum for cleaning the insides of steerers, seat tubes and the like. I used to clean the inside of lugs with this too.
You'll need a vise, an 8" piece of round steel, 1/4" would be OK but 3/8" is better, a variable-speed hand drill, a hacksaw, and a roll of cloth abrasive strip 1" or 1-1/2" wide, fairly coarse (60 to 120 grit).
Clamp the steel rod in the vise and hacksaw down from one end, right down the middle until you have a slot an inch or 1-1/2" long (depending on how wide your cloth strip roll is). Chuck the unslotted end in your variable-speed hand drill. Take your 1" or 1-1/2" wide emery cloth strip and anchor one end in the slot, and run the drill motor slowly to wind up abrasive strip onto the tool until it's a tad bigger than the diameter you want, then tear off the strip from the roll you're feeding it from.
Straighten the windup into a straight cylinder, and tighten it to make it as small a diameter as you can, then make it smaller as necessary by ripping some cloth strip off until it'll just barely fit into the hole you're trying to clean up. It tightens further in use, and abrasive wears off, so you want to really try to have it be as large as possible at first.
Only the outermost wind of the cloth does any sanding of course, but after its abrasive is worn off you can unwind two or more winds, rip that piece off, flip it around and overlap the worn end under the remaining cloth end, and wind it back up, so the good end of the piece you ripped off is now the outside. When that's worn, throw the torn-off piece away, rip a new piece off the supply roll the same length or a little longer, and tuck that under the end of the windup - you can repeat this last step as many times as you want, replacing only that last little bit that gets worn out, with the "hub" you built up staying on the tool.
Mark Bulgier
Seattle, Wa
USA
> -----Original Message-----
> From: OROBOYZ@aol.com [mailto:OROBOYZ@aol.com]
> Sent: Wednesday, August 29, 2001 5:50 AM
> To: Roadgiant@cs.com; twrawson@worldnet.att.net
> Cc: Classicrendezvous@bikelist.org
> Subject: Re: [CR]stuck handlebar stem
>
>
> In a message dated 8/29/01 1:53:37 AM Eastern Daylight Time,
> Roadgiant@cs.com
> writes:
>
> << I've soaked the space between headset and stem with liquid
> wrench but how
> to turn the bars without torqueing the fork? >>
>
> I'll give a shot at this as it comes up once or twice a year
> in the shop.
> You need:
> - a substantial vice mounted securely on
> - a substantial work bench
> - a two by 4 at least 5-6' long
> - a big supply of rags
> - help mate or two...
>
> Remove everything you can from the frame and fork maybe leave
> cranks & bb in
> but as much as possible.
>
> Turn the frame upside down and insert the stem, (h. bars
> removed) in the vise
> with the vise jaws heavily pad so that it won't mar the stem
> (!) The fork
> blades should be pointing up.
>
> Insert the 2 x 4 between the fork blades as far as it will go
> up towards the
> crown.
>
> Now it is a slow process of twisting, using the huge
> mechanical advantage of
> the two x four, and pulling upwards with the frame and fork
> to pull out the
> stuck stem. Care has to be taken that the fork blades are not twisted
> instead, and that nothing gets "chewed" in the process.
>
> If this doesn't work, you are in BIG trouble! I have had to
> cut off the stem
> even with the top of the headset and then section the
> internal stem remnants
> out with a hack saw blade to remove it in pieces... That is a
> hateful job
> that takes forever and I won't do again unless absolutely desperate!
>
> I have heard every kind of external treatment to free these
> parts.. Liquid
> Wrench, heat and cold, soaking in Ammonia.... None of those
> methods really
> seem to work reliably!
>
> Good luck!
>
> Dale Brown
> cycles de ORO, Inc.
> 1410 Mill Street
> Greensboro, North Carolina
> USA 27408
> 336-274-5959
> Fax 336-274-6360
> <A HREF="http://www.cyclesdeoro.com">cyclesdeORO.com</A>
> <A HREF="http://www.classicrendezvous.com/main.htm">Classic
> Rendezvous</A>