Very cool
Nice wheel! Looks like a good Goldilocks amount of tread.
Went for a ride this morning and braking was smooth. Success!
Gave my trusty old UDC cf base the third major overhaul.
Originally I build it with the oldschool bolts sticking out the seat approach (almost 7 years ago) and alongside the usual problems with it like hitting your fingers on those damn nuts constantly, I was 14 or 15, so my drilling and filing wasn’t all that accurate.
Then I used M5 T-Nuts everywhere except the back bumper and custom M5 allen bolts that use a 4mm allen key (did those by grinding the threads of M6 bolts using a bench grinder, and cutting new M5 threads, and no I don’t know why I thought that was a good idea either, but it held up surprisingly well, I think I wanted to keep the holes in the base as small as possible, and still use the bigger allen key).
I realized how stupid that was a bit later, and used M6 T-Nuts, still had the bolts sticking out method for the back though.
Now, recently I got fed up with my inaccurate holes, and T nuts spinning because the bolts never went in without fiddling a lot and so on, and since I obtained a KH Street saddle, I used parts of the steel reinforcement plates with the middle cut out, and speedholes added for extra lightness, to replace the T nuts, and in the back I welded two sleeve nuts to a strip of Volvo fender, to make sure they won’t spin.
I also ground down the front of the base to finally make the handle fit right, and sed a strip of edge protection stuff from a hardwarestore, and some clearcoat to make it pretty. Some stuff I am not happy with includes how much I had to elongate and enlarge some of the holes to get everything in the right place this time around, but I believe it will still be plenty strong.
I originally wanted to do a little step by step post, but forgot to take pictures…anyway, here is the final product:
Good job Finn carbon bases are a bitch. I did mine with tnuts and while they work ok I had to shorten my bolts which was done witha hack saw and it makes it impossible to get them as the threads arent smooth. I need to buy new bolts that are shorter. Also One bolt went in at a random angle and im fairly sure screwed the thread in a tnut. Basically I have just avoided taking my base apart for a good 9 months. Not looking forward to the day when I have to fix it all up…
In this tread we have a little collection of these “Hugo-Struts” as we call them (as Hugo was the first one who built such a thing).
Ah, thanks. I’d seen those pictures before but couldn’t remember the thread they were from. That’s where I got my inspiration from :).
Nice job!! 
I need to learn to weld!
Is brazing easier to start with? And cheaper?
I could add a brake to my nimbus 11 frame…
Stick welding is the cheapest, but less versatile than other processes. I did that brake mount with an old stick welder, because it’s what I had available, but it’s not really the best option for welding thin-walled tubing like using in bicycle and unicycle frames.
Lugged brazing can be very strong. This is how a lot of older bike frames were built. The lug is basically a socket that the tubing fits into, and then the brazing filler metal gets sucked into the very small gap between the tube and the lug via capillary action. Very strong but requires lugs and so not really suitable for hacking. Example:
Lugless brazing is also done sometimes. In this case the filler metal forms a fillet similar to a weld bead. The base metal is still not molten. You need a very tight fitup for a strong joint, and I understand there is some science to the fillet radius in terms of managing strength. Not as strong as welding at first glance, but there is less heat going into the base metal so it can be stronger sometimes. Example:
Fillet brazing can be done with a TIG welder, but usually it’s done with a gas torch. With an oxy/acetylene rig you can heat, cut, weld, braze (both fillet and traditional) and silver solder. It’s very versatile and a lot cheaper than a TIG setup with all the bells and whistles. TIG can be cheap if you have a more basic setup (scratch start or lift arc), but once you want to use a foot pedal, use AC with high frequency start (for welding aluminium) and have good adjustability it can get pricey.
My “new” $40 Craigslister!
This was a one-off, aluminum 29er built by local shop with Alex rim. I replaced the bearings, then added handle bar, Schwalbe Big One, and rattle-can finish. Now it’s a fast, light road machine.
Sweet! Really nice work there. You’ll have some fun on that.
That looks very nice and fast!
I’ve almost finished my 27.5er. Won an old Nimbus castle top 29 frame off ebay for £10.49 so got to work, Nimbus steel disc hub, KH freeride rim, Maxxis Aggressor 2.3 tyre, Nimbus alu post, seat clamp and Stadium seat and KH plastic pedals on 125/150 moment cranks.
Can’t wait to get a ride on it!
Carbon Seat!
Recently made a carbon seatbase compatible with regular KH hardware.
Seeing how almost everybody with the NNC flatfish uses the heavy KH adjustable seatpost and no one angles it down, I made the adjustment angle higher (to a maximum pictured), and a minimum of flat (as opposed to down).
The layup is 5 layers of 200gsm 3k, with reinforcements where I expect will have more stress. The final weight of this trimmed seatbase (before drilling and installing the nuts) is slightly under 115g.
Which brings me to wonder, what was the weight of the NNC, and with the existance of the flat KH bases, is anyone still interested in buying these things?
HI Wenn,
great job. This base looks great !
I cannot comment on the NNC weight as I never had one.
However, I can say that you will find people interested in buying some if you plan on making them available for purchase. Keep in mind that the few carbon base available seems to be from either private handmade runs or limited test runs.
Depending on the price, I can be part of the people liming up for one 
Hi Wenn,
Nice job on that seat base. I’ve often thought that saddle design in unicycling could learn a lot from bikes. Currently we try to attain comfort almost purely in the padding. The biking industry knows that you actually don’t need much padding at all if the shape is right. I would love to one day see a uni saddle that has the relief channel built into the CF seat base itself, instead of purely in the foam that is slapped on top of it. This channel would also help strengthen the seat base too. You could then use much thinner profile foam, only on the top and sides.
Good work,
Mark
Yes, I come from a bicycling background too, and although i do not care too much about weight there, I simply cannot accept how heavy things are in the unicycling world. For reference, my saddle is a Dash Strike weighing something like 95g including the saddle rails. No offence to Roger or Kris Holm it you happen to read this, I understand why things are this way, and I probably will not be unicycling if saddles cost as much as bike saddles or broke on the tenth drop!
I do understand the want for the perfect saddle shape, and am working towards that too. This is an integrated saddle i previously worked on, its length is as long as a KH saddle with a Muni bar, ridiculously stiff but at a more reasonable weight. Sadly, the front grab handle was not too comfortable and I could not think of a better way or attaching the rear bumper so I am reverting to mounting the plastic handles.
Edit: Mark, I believe unicycle seats need a certain depth of padding for optimal performance. I actually did ride this pictured seat for 15km without padding (and simple thin unpadded shorts) and while it was not especially uncomfortable, it required full hands-on riding as any little bump would throw me otf the surface of the seat and allow it to shift behind me. Perhaps it would be ideal to have a perfectly shaped carbon base then a deep (1.5cm?) layer of soft foam to keep our butts planted on the saddle when not holding the handlebar
I might be.