I always thought this was pretty cool.

[DougC]

I got the last of the metal I needed today to build three hubs.

I need to cut the hubs, which are 2" wide, have a 3.5" ID and a 5.375" OD. I had planned on cutting them out myself from some 2" thick plate, but I lucked out at the metals place and they had a few feet of some mild steel tube that was 3.5" ID and 5.5" OD, so I bought 8 inches of it. I still need to slice it into 2" wide rings and to the rest of the machining, but that still saves me a TON of work.

The blocks and square plates on the table (and the rusty tube) are the metal for the hubs; the sprockets and chain are for something else.
~

 

[DougC]

Still in progress.

The all-silver ring is cut to its starting size. The other two near it are faced off on one end but nothing else done yet. The thin big rusty ring in back is the leftover.
The square 1/2" thick plates are now cut into circles (the tapered center hole was just to spin them on the lathe, they'll have square holes in the centers when they're done).
The small blocks are cut down "squared" to the starting sizes they need to be; the three long "axle" blocks are still untouched....
~

 

[DougC]

I ordered a set of bearings to test-fit with.
BIG bearings....

The big bearings I was kinda worried about side-to-side play, since they are only just radial bearings and there's no method for snugging them up sideways--but they really feel pretty tight as they are. It might be apparent when they're built into a wheel, but right now there's no perceptible sideways play in them.

The smaller ones are the steering bearings which are slightly smaller than 1" head tube bearings, but these are still rated for 600 lbs and they only cost about $7 each. Even if they "only" last a year of casual riding use, that's still not too bad an expense.
~

 

[deorman]

Really cool that you're giving this a shot. 8) I wouldn't mind this turning into your project thread, but you might want to start your own. :wink:

 

[DougC]

Really cool that you're giving this a shot. 8) I wouldn't mind this turning into your project thread, but you might want to start your own. :wink:

If I did that, they'd just look at it and be like "you're making a what?,,,,, and,,,,, why do you want one now?"

-----

The lathe started making squeaky noises lately, so I've been chasing that off and on. It only squeaks when I'm USING it. When I take the cover off, take the drive belts of and start spinning the motor and pulleys by hand to find where the squeaking is coming from, everything is silent. :|

I got one hub and two side plates cut for the big bearings. The side plates have rectangle holes in them, but still aren't finished.
one pic, bearings sitting on plates next to hub-

another pic, one plate + bearing sitting in the side of the hub

 

[DougC]

What is the thread size of a typical front axle now? Sheldon Brown site gives 9x1mm ....... if I read it correct.

The only wheel I've got on hand is the Worksman with a front drum, and I know that it uses an extra-thick axle.

 

[DougC]

Okay, one axle is mostly done. It still needs holes drilled in each end and threaded for studs.

The reason for using studs is that if the studs strip where the nut holds the wheel on, they would be easier to replace than if you stripped out the holes in the axle itself. I may just end up using 3/8-16, since that's the common hardware store size of threaded rod available in the US.

This part has a bunch of little mistakes, but my ancient camera hardly picks them up. It's still useable tho', and they won't be visible when the hub is together since they're near the center. The next couple will work out better.

It is also kinda possible to get an idea of how this will work now.
The axle has pockets on the top and bottom of it for the steering bearings. There's going to be a couple more blocks (I have not made yet) that fit inside the hub, above and below the axle, and in-between the side plates. There will be bolts running through both side plates and the blocks to hold them together, but those holes are not drilled yet.

There's also going to be a steering arm on one (or both) sides, also held on by the same bolts. Aint done that yet either.

------

Making complex stuff like this axle is a LOT harder than I thought.
I dreamed about owning a mill and lathe for years but hadn't used any since high school (~20 years ago). And didn't try to make anything complicated in shop class. I had assumed if I had enough time making anything would be pretty easy, but errors creep in a bunch of different ways and they tend to compound themselves as you make more and more cuts on a part. Its a lot of fun but can be frustrating because if there is even one tiny metal chip in the vise jaws or lathe chuck jaws when you clamp the part, or if you forget to tighten one tooling bolt it will flex,,, and then that throws everything else off.

 

[gowjobs]

What is the thread size of a typical front axle now? Sheldon Brown site gives 9x1mm ....... if I read it correct.

The only wheel I've got on hand is the Worksman with a front drum, and I know that it uses an extra-thick axle.

Standard bicycle axles are 3/8" dia., though some older lightweight bikes have slightly smaller dia. axles in front. BMX and downhill bikes use 14mm and even 20mm axles.

 

[DougC]

What is the thread size of a typical front axle now? Sheldon Brown site gives 9x1mm ....... if I read it correct.

The only wheel I've got on hand is the Worksman with a front drum, and I know that it uses an extra-thick axle.

Standard bicycle axles are 3/8" dia., though some older lightweight bikes have slightly smaller dia. axles in front. BMX and downhill bikes use 14mm and even 20mm axles.

The problem is the threading.
The English size that Sheldon gives is 3/8-26, and there's no standard tap in that size. The closest is 3/8-24, which is a National Standard Fine size. I was wondering if the 3/8-26 was an error or not. Even if it's not, there's no way I'd use it, since there's no easy source of studs in that size.

The common size of 3/8" threaded rod sold in hardware stores is 16TPI, which I think may be too coarse to hold very well. I may just cut some grade-5 bolts off to make some 24TPI studs.

 

[gowjobs]

There have been 24tpi and 26 tpi 3/8 axles, though 26 is more often the standard for bicycles.

 

[deorman]

Some auto part stores carry generic automotive or ARP studs in little plastic drawers.

 

[DougC]

I still haven't decided what I'll do for the axle studs. I haven't gotten to any auto parts stores yet.
It turns out that M9x1 isn't a real common size either; local hardware stores only carry the even-mm sizes of bolts and nuts. So they had 8mm and 10mm, but no 9mm at all.

------

Still not finished but a couple more steps today...

It's not obvious, but the side plate hole edges are now cut to 25º angles, so the axle can actually turn as far left-and-right as it should. The steering range is 50º total.

All the inside parts fit inside right now, but the corners of the top & bottom blocks need to be trimmed off to make sure they don't rub the hub.

What the middle pieces look like un-stacked.

 

[Skipton]

Just found this pic

 

[DougC]

I haven't gotten to the axles yet but have gotten the hub mostly cut.

First most of it was cut away on a lathe,,,

Then the rest was milled out.
The way I tried to mill left some tool marks, but the next two won't look nearly this bad. Even this one doesn't really look that bad in person, the camera flash just makes them show up more. If it was painted with a couple coats of flat paint, they'd be much less noticeable.

The spoke holes still need to be drilled. Also the hub is a lot lighter now too, but the rest of the parts are still heavy.

Did anyone ever find any bicycles with this kind of front hub? I kept looking for a long time and didn't find any. Pretty much I found that weren't the usual kind of forks, were the single-sided kingpin-type front end, or negative-trail forks that stick out way forward like on the lowrider bikes.