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babelloyd
10-22-2010, 12:46 AM
With the help of a pro welder and a $4000 Millmatic 200, I welded the basic frame!

Today I called a bike shop looking for three 20-inch 48-spoke wheels. The guy said that if I'm custom building the hub flanges, then I'd need to get each spoke custom-cut for about $2 per spoke. Then he said I could instead make my custom flanges the same size as the hubs they're replacing. I presume option #2 is what most Zombies go for. Of course, if the hubs I get are not 2.5 inches in diameter, then I'd need to custom-make the hole punching template. I have no idea how to do that, but I have a machiney-type acquaintance who owns a CNC, and he might be able to help me.

However, how hard is it to precisely measure the diameter of a wheel hub? Doesn't the axle or the nut get in the way of the ruler? I suppose a flexy sewing tape measure and an geometrical equation could do the trick.

Anyway, once I get the three wheels I need, I may be asking here if anyone has a hole-punching template for a hub diameter that is something other than 2.5 inches.

ken will
10-22-2010, 01:13 AM
However, how hard is it to precisely measure the diameter of a wheel hub? Doesn't the axle or the nut get in the way of the ruler? I suppose a flexy sewing tape measure and an geometrical equation could do the trick..

Calipers work the best. If you don't have calipers you can use a large adjustable wrench or a pair of needle nose pliers or a pair of sissors.

babelloyd
10-22-2010, 01:16 AM
Yeah, wow, that seems so simple. Man, this is why I talk to people about this stuff! Thanks tons!

Odd Man Out
10-22-2010, 01:41 AM
Anyway, once I get the three wheels I need, I may be asking here if anyone has a hole-punching template for a hub diameter that is something other than 2.5 inches.


No problem -- shoot me a email once you get the dimensions and I will get a CAD drawing out to you within 10 minutes after I read your message -- easy peasy.

John Lewis
10-22-2010, 03:38 AM
If you make the flanges bigger then you can space them further apart and still use the same spokes. On the Wolf for example this was done to make the wheel stronger. An on line spoke calculator can help you work out the diameter and spacing needed. Darn I can't recall which one i used but it's on the forum somewhere anyway I think.

John Lewis

babelloyd
10-22-2010, 12:06 PM
John Lewis: Thanks for the tip! I found three online calculators:

http://www.bikeschool.com/spokes/index.cgi
http://www.wheelpro.co.uk/spokecalc/
http://www.machinehead-software.co.uk/bike/spokes/spoke_length_calculator.html

Unfortunately, they're too complicated for me to use, I think. I may just go to a bike shop for help, like Brad did on page 55 of the DeltaWolf plans.

Cheers!

vrooom3440
10-22-2010, 12:22 PM
I would recommend spending the time to understand the spoke calculators personally. Not all bike shops will have the expertise to do anything custom as for many the wheel is a replaceable unit unto itself.

I use a calculator from DT spokes and the biggest problem I have with it is converting back and forth between metric and the inches I am accustomed to.

babelloyd
10-22-2010, 06:41 PM
Thanks for the tip! I'd love to spend the time to understand a spoke calculator. Maybe Sheldon Brown's site can help me. But I really am not very smart at this stuff. I truly want to learn, but I feel a bit like a math-challenged student in a calculus course sometimes. And sadly, I find the ESL "help" for the DT calculator bewildering.

But I'll keep trying! :-D

babelloyd
10-22-2010, 06:42 PM
I've sourced some 48-spoke, 20-inch chrome rims that have been marked down to $10 CDN each because "The chrome isn't very good". Is that a good deal? Of course, I'd have to buy the spokes then too. And that means I'd have to figure out spoke length.