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babelloyd
04-25-2010, 03:24 AM
Hi folks!

I'm super excited to have just chopped out and ground my first bottom bracket, using AZ's tutorial as my guide!

Now, the head tube is next. However, in the bike chopping tutorial, the photos show the severed head tube without the cups on either end (seen here: http://atomiczombie.com/home/headtube/figure-06.jpg). What happened to the cups? Should I cut them off of my chopped head tube? Or did that example bike just not have them?

Those cups seem like they would be useful/essential, so I'm a bit puzzled. They also seem like they would get in the way of grinding the paint off. Any comments on that?

Cheers and thanks,

Dave

PeterT
04-25-2010, 06:53 AM
The cups are a press fit, insert a drift from one end, and knock the cup out, then turn around and knock the other out, the bottom bearing cup is slightly longer than the upper one.

PeterT

savarin
04-25-2010, 09:43 PM
Hi Dave , as Peter said, just knock them out first with a drift.
A drift is any length of any metal (solid bar, tube, long nail etc) that will easily fit down the tube and cups.
Angle it so the bottom edge catches the lip on the inside where the cup is pressed into the tube. Start tapping around so as to loosen the cup and pop it out.
It may require a hefty whack at first as some cups are fit very tight.
Dont just keep whacking in one spot move it round the bottom of the cup to evenly force it out.
The last whack will often send it spinning across the workshop so be prepared to catch it.

babelloyd
04-25-2010, 10:00 PM
Thanks guys!

So I keep those cups and reuse them when I'm creating my custom bike later then?

Dave

babelloyd
04-26-2010, 02:25 AM
Ah, I see that the answers to all my questions in this thread are in the "Head Tube Basics" tutorial. I have done just what Kool Kat warns against: asked questions when the answers are here on the site. In retrospect, maybe the "Bike Hacking" tutorial could use a cross-reference to the "Head Tube" tutorial? Or maybe I'm the only newb who would ask the questions that I asked.

Anyway, thanks for your patience!

Dave

Cheezy Rider
04-27-2010, 12:48 AM
Nope. Ask away. That's how we all learn from each other. Keep the cups and bearings. There are various size cups, so keep em all. You'll use them somewhere on another project.
Happy building!!!

TheKid
04-27-2010, 01:11 AM
That subject comes up from time to time. Next, you'll probably want to know how to reinstall the cups. If you install the cups before welding the head tube in place, you may fing the cups are in a bad position. My method is to weld the head tube in place, then start each cup by gently tapping until they just catch. The place a block of wood over the cup and whack it with a hammer until the cups are fully seated. You'll find the method differs between our members. Just thought I'd get the installation ball rolling.

savarin
04-27-2010, 02:27 AM
No2, I use the vice to squeeze them in

Dont let the RSPCA know but theres usually mare than one way to skin a cat:rolleyes4:

John Lewis
04-27-2010, 08:45 AM
I use a piece of all threaded rod, two big washers and two nuts.

To make a useful tool for removing the headsets.

Get a piece of tubing that just fits through the head tube. Cut some slits with a hacksaw ot disk. Spread the resulting tongues a bit. All you do is pull it up into the head tube. The tongues spring out a bit. Give the top of the tube a whack and out pops the cup. Second one the same way. Very easy. Save the slotted tube for next time.

John Lewis

TheKid
04-27-2010, 10:32 AM
No2, I use the vice to squeeze them in


I use the vise whenever possible. But if the head tube has to be installed while on the vehicle to get the correct angle, sometimes the cups may become damaged. Next time, I'll use John's method. In reality, it's also a vise, the washers being the jaws.

babelloyd
04-28-2010, 09:42 AM
Great ideas! Thanks!