Pondering DIY Saddle and Seatpost

So I’m a beginner currently enjoying the luxurious comfort of a Torker CX stock saddle… but I’m also an engineer who has ended up in a machine shop customizing gear for every hobby I had in the past. As a result, when I’m not able to be actually practicing, my mind is in overdrive planning, for example:

Say I got a nice saddle or two (worth more than my current uni, but that will change), that had a pivotal mount. I can’t get a 22.4mm pivotal post from UDC at all, and the 22.4mm ones available for the BMX market are way shorter than the 350-400mm I’d need. Could I get a larger diameter post, and bolt or silver-braze it over a piece of 22.4mm OD steel DOM tubing?

What’s the typical wall thickness on a steel seat post anyway? (I’d have to saw off the chamfer on mine to be able to measure it)

If I were going to build a saddle from scratch, say on a multilayer aircraft plywood or aluminum bar base, what would be a good way to attach it to a seat post and make the angle adjustable? I know where there’s a buzz-box stick welder I could beg access too, but just duplicating the traditional four-bolts-on-a-curve mount by (very) amateurishly welding a piece of flat stock to tubing seems limited. What about turning a piece of steel or aluminum to fit inside the end of the seatpost and cross drilling it for a pivot bolt? This could then perhaps fit into a sawn-open piece of steel or aluminum square tubing or channel on the bottom of the saddle. Or perhaps I could use a T shaped piece on the saddle and mill a notch for it in the post insert?

Or what about bike style mounts with a clamp and rails mechanism?

Anyone ever tried something like this? I’ve seen the threads on reworking saddles, but am kind of curious about crafting something from scratch. Or should I just order a long 22.4 mm traditional seatpost and something like an impact naomi and find other ways to occupy my mind when I’m not actually practicing?

You could start making your own version of something like this:

Seems like there are a bunch of folks waiting to throw hundred dollar bills at whoever does.

The ones I’ve got here are all 60 thou / 1/16" / 16 ga / 1.5 mm-ish.

I wouldn’t spend another cent on your current uni. You have confirmed you can do it so it served its purpose. Time to upgrade to a more suitable uni.

Instead of thinking about what you could do to uni, think about riding. For most of us ordinary guys it takes a lot of time to get good at it. You seem just crazy enough to take this on seriously so do the fun bit on the pedals.

BTW I changed from my learner which had a crappy seat, a 22 mm post and a skinny wheel to a half decent but nothing special Quax when I could ride up to 100 metres on the learner.

I immediately started riding hundreds of metres and climbing hills. Two weeks later I was riding the 8 km to town and back. Two months later I came to realise that it was also too small. I am now on a 26 inch wheel and it feels about right for where I ride.

Now when I try riding the little uni I started out on, I really wonder how I learnt at all. It must have been just sheer will to do it. Or riding the 20 inch to town for that matter.

I’m indeed pondering getting a second unicycle (perhaps a more rugged 26" for bike paths) - but but a big part of that would be so that I could leave the 20" CX at the office for to ride for 5 minutes at a time when I want a break and have something else at home (it will be a long time before I’m ready to brave the Manhattan street traffic in between, and carrying it in a shoulder bag gets old). It seems like learning to freemount, turn better, idle, maybe ride backwards, all should be possible on the cheap 20". I do think a better saddle and longer seatpost would be good, and as long as any serious-money components I buy would be portable to something else (a future 19 or 20 trials uni?) at the cost of a suitable diameter seatpost, I don’t have an objection in principle to putting a good saddle on a bad unicycle.

But in addition to the opportunity to tinker, one of the things that would be attractive about figuring out an adjustable, DIY seatpost-saddle joint would be that if or when I come up with a configuration I like, I could easily and cheaply outfit multiple unicycles with it.

I started last year on a 24" Sun Classic which is a very basic unicycle. I couldn’t stand the seat so I purchased a KH seat which cost 3/4 of what I paid for the unicycle. When I started to learn to free mount I picked up a 20" CX Torker thinking it would be easier. It wasn’t easier. Just too squirrelly with that 1 inch tire width. Also the seat and seat post clamp are terrible. I ended up learning to free mount on the Sun but later picked up a 20" LX Torker for learning to idle. The LX is much better. I still have the CX but plan to give it to a local elementary school that teaches kids to unicycle. That’s great if the CX works for you and/or it’s your only option but it’s not a unicycle that’s recommended for adults.

I’ve since purchased other unicycles but will hang onto the Sun as a loaner. It’s better than the CX.

Thanks! That’s the info I was looking for.

Ultimately, I’ve ended up ordering a better unicycle to keep at home for outdoor use, so instead of the DOM tube while I was at it picked up a 700mm basic post for the “office toy” CX - figuring even after I cut it down to the ~400mm length I need, I’ll have some tubing left over for experiments like seeing if it would fit inside a larger one, etc.

Hmm, turns out the Kris Holm adjustable seatpost won’t fit a Nimbus or Impact saddle as the curved saddle interface piece gets much wider on the back than in the front, while those both have molded indentations for an interface piece about rectangular in width. It’s potentially still usable as-is with a scratchbuilt saddle, but I have to decide if I want to saw off the wings, try to make a new rectangular top part for it, or just put it on the shelf until I decide if I’d rather modify or resell it…

and the goal had been to avoid spending time in the machine shop…

I don’t think I understand why the KH post won’t fit a saddle with a KH base (Nimbus/Impact). Could you explain this better. There are plenty of people using these combinations without issue. There are two KH bases, and most Uni saddle are built on the more curved pre-2009 base, while a couple Nimbus, and all current KH saddles are built on the 2009 base.

That used to be the case but the newer nimbus and impact saddles now use different bases if I’m not mistaken. The saddle I got on my new nimbus II last year was a base that I had never seen before, I’m guessing it’s the same base that EOAU has.

The (brand new, just received) Nimbus Gel and Impact Naomi saddles have molded-in depressions for a basically rectangular seat post interface plate around 35-36mm wide. I thought that was what pretty much everyone was using.

In contrast, the one on the KH adjustable seatpost is about that width at the front but expands to 50mm at the rear. The hole positions remain the same - it’s just that the piece of metal gets wider as it goes back.