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Neat work.

You realise that you now have to upgrade the rest of the fork to match its pretty crown?
 

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Discussion Starter · #87 ·
I have been pretty busy with other projects lately so I have not had time to update this thread. There has been slow but steady progress on the fork. In this pic I have bored a few random holes in the bottom of the crown to reduce the weight a little bit.
 

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Discussion Starter · #89 ·
The main problem that had been holding up finishing the crown was a slitting saw to cut the slots so that the stantions can be clamped in the crown. We didn't have the right width of saw at work so I had to track down one that was the right thickness. A coworker found one that is 3/32" (.094") cutting width. I was hoping to find a 1/16" (.062") like the original crown but I decided not to be too picky and went with the thicker saw. The setup in the milling machine took a little extra work. I had to convert the mill from vertical operation to horizontal and turn the vice sideways on the mill table. That's not hard to do but it is time consuming when you are in a rush during a lunch break.
 

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Discussion Starter · #90 ·
The slots are now cut and the next step is to press in the steerer tube. I machined a scrap piece of steel plate for the crown to sit flat on and machined a scrap of aluminum to sit on the steerer tube so that I was not pushing directly on the tube. I have pushed a few steerer tubes in and out of old marzocchi forks and it's surprisingly easy. My crown steerer assembly has an interference fit of .003" which is quite a bit for a bore that is only 1.185" diameter. The standard fit on most machinery that we want to be permanent is .001" per inch of diameter.
 

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Discussion Starter · #94 ·
DUde - awesome progress! For those of us not from a machining background - how much force is required to press that crown in?
To be honest, I didn't even look at the gauge on the machine to see how much pressure there was. I too busy staring at steerer tube to make sure it was going in nice and straight and smoothly. I do know that when I pressed the steerer out of the stock marzocchi crown the gauge did not even move. Steerer tubes go in and out pretty easily.
 

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Discussion Starter · #98 ·
I am currently waiting for a new set of fork seals that are on order and I also need to make some internal spacers to limit the travel but I could not resist test fitting the fork together. So far everything lined up nicely and bolted together without any trouble. Now that I know it goes together I just need to worry about how much it will alter the geometry of the bike.
 

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Discussion Starter · #100 ·
Looking great. Do you have drawings and numbers of what you've done? Might be worth something.
I had no plans on making any more after this one so I didn't keep track of all the numbers. It wouldn't be too hard to make up a drawing and get some dimensions now that I have a sample piece to measure.
 
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