hammering out headset cups?
 

I want to replace/swap around a couple of headsets on my bikes. When I was a kid we used to just hammer the cups out with a big punch and hammer. Can I abuse modern CaneCreek or Aheadset aluminum cups the same way or do I have to fork out the $25 bucks for the fourpronged Park cup remover? I haven't seen alternate methods mentioned by Zinn or any other books i've read.

Does anyone have a good way to do it on the cheap? Thanks.

When I replaced mine, I used copper pipe-figuring copper would give before the harder metal in the cup. But I was replacing the headset anyway, so didn't matter. I have heard of using a piece of pvc (plastic plumbing pipe), cutting 4 slits lengthwise in it, then spreading out the ends with a cork or large bolt.

I used a punch and hammer on my Trek 6000 which is aluminum, and my wifes Trek 920 which is cro moly,just don't use a lot of force and they should come out without damage.

When I replaced the 20 year old JIS no-name headset on my World Sport a few weeks ago (I ran it for a year with loose bearings before it was no longer useful) I didn't know that I could still get a decent Tange steel JIS headset. In hindsight, that's exactly what I would have done.

I bought the cheap nashbar threaded headset, punched off the cups and races with a long piece of all-thread rod (gently, but it didn't really matter because I was throwing away the old hs) or a punch. I don't think I'd ever do it with flimsy aluminum cups.

I also gingerly filed down the JIS fork crown race to ISO size with several grades of files and emory cloth until I got an absolutely perfect (feeling) fit, but maybe that's fodder for another thread. Honestly, to do it all again, I'd either replace the rather crummy bike or just get the proper sized headset. It does work like a charm, but it was an awful lot of trouble for a mediocre (at best) headset on a low end bike.
[note: I only added this because I didn't find, either searching here or the internet, any chronicles, either successful or otherwise, of a DIY low-budget fork crown machining and I thought this might be of interest to others.]

If you have an old steel fork, you can cut it off to the proper length (it needs to be longer than the head tube), cut 4 slots in it and flare the ends with the slots a little. Then you can pull it into the head tube (which is why it has to be a bit longer than the tube) and the flare will snap into the tube as soon as it clears the head set. Then you just drive the headset out with a mallet. All you are doing is making the same tool as Park sells (although the Park tool is really sweeeet ;) ). I did this for a long time before I bought my Park headset remover.

[edit] The punch thing works too but it's not nearly as elegant.

Holy crap, I did the exact same thing 2 weeks ago: I used a 1/2" threaded rod (the same one that I was going to use as a component in a homemade press) as the punch.

Anyway, the secret is to simply tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap ... slowly but surely, it'll come out no problem.

A neat trick I learned for tapping a new crown race in place: Use the OLD crown race as an in-between layer, so that while you're directly tapping on the old race, it is in turn using it's matching rounded edge to push down the ring beneath it. The tight fit on the steering shaft prevents the old race from angling too harshly, making sure that the point of impact is fairly wide. Still, as above, tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap tap, slowly but surely.

With the punch/threaded-rod/screwdriver technique to remove the cups, be sure to alternate back and forth to opposite sides so you don't angle the cup.

Good trick to get the crown-race back on is to use an adjustable crescent-wrench. Put the jaws on both sides of the steerer, tighten the wrench so it's snug, slide down onto the crown-race. Tap with hammer on the sliding mechanism that joins the two jaws and you'll be able to apply force on opposite sides of the race evenly. :)

I use the Park Tool. Easy to use, and it was $20 something on ebay.