Uppy/downey posts, anyone built their own?

Just considering lashing one together… How hard can it be?

Anyone had a pop at making their own?

Thoughts?

How hard can it be?

who knows, but the penalties for failure are quite high.

The embarassment of presenting yourself at A&E with half a seatpost up the jacksie is also something to consider.

How hard can it be?

Judging by the seemingly high rate of failure, it’s not the easiest product to design and manufacture. That’s for several large-ish companies, not one person with a lathe…

There’s a lot to fit into a such a small space and there’s a lot that can go very wrong.

(very happy with my i900r – NOT bought from SSC)

I reckon you could knock one up from 2 old seatposts (where one can fit inside the other) and a small piece of steel bar secured with a split pin. Cut saddle clamp off the larger post, and cut the narrower one down to desired length. Drill holes through where you want full height to be, and the same for the dropped height. Then you could just slip a small piece of steel bar through the holes to support the post – you could drill the bar at either end and use a split pin to stop it going straight through. Or if you were feeling really brave, you could do away with the bar and just use a seatpost clamp to squeeze the 2 halves of the post together at whichever height you choose. Let me know how you get on.*

*You may not actually want to try any of this. 🙂

People used to use those titec 2-part seatposts and the spring out of a Boxxer IIRC?

For a DIY jobbie I was thinking it’s probably best to take a more basic approach:

Index plunger, a few holes in a shaft, some sort of guide pin/block to keep things straight, plenty of bushes and just use a boot or bit of neoprene to keep the shite out, more the gravity dropper school of thought than the Aesthetes choice Joplin/Speedball method of maximum complexity/part count and plenty of people complaining about failures…

“Agricultural Engineering” all the way…

By the time you have a working one you will have spent days and days in the garage bodging one up.

It will forever be a prototype / bodge, when you could have a working one for a few hundred quid.

Aren’t they based on a office chair anyway? Have a go.

By the time you have a working one you will have spent days and days in the garage bodging one up.

It will forever be a prototype / bodge, when you could have a working one for a few hundred quid.

Where’s the fun in that?

Your suggesting I substitute, fiddling with mechanisms and playing in the garage for a bit of practical retail therapy…

I’m not a girl…

Easy

In all honesty I fully expect building a working prototype will most likely cost far more than buying a brand new Gravity dropper, but I do like to make things…

Simply buying stuff from CRC, SSC and co all the time gets a bit dull after a time…

Just to reitterate my original question, Has anyone ever had a crack at this sort of thing before?

quick release clamp & two lines on your seatpost…

The only thing I’d pondered over was a seat clamp with a twisty ‘kn0b’ rather than a lever, making it possible to twist… drop…. tighten on the move, even if you have to get off or stop to pull it back up again.

joe breeze did it years ago (1991 advert), but too basic and minimalist to catch on? I’m sure if someone made the HR out of titanium/carbon fibre it could be made expensive enough to sell 🙄

Yep we’re all well aware of the hite right. a good solution but I reckon I can do better if I try…

I think you should go for it. All the previous offerings have been unambitious though. I want to see linear motors and wireless remote control.

Oh and an ejector seat . It MUST have an ejector seat.

colonel wax – I do hope that’s not your photoshop-ing, very poor 😀

No way, that’s my MS paint CAD design. Prototype’s nearly ready and then I’m going to market them to the Garly IT Freeride brigade, office chair comfort to the max.

You taking deposits? I’ll have one in red.

How hard can it be?

Dunno how hard, but there is a high pressure air one running around locally for about 6-7 years now (from a bloke called michel).
Not super air tight, but when it’s not going up any more you just use your pump and off you go ;).
Apparently michel struggles to sell the patent or get someone to build it for him.

Will accept deposits from potential suckers customers via Paypal 😉

Sounds like fun. I’d be tempted to base one on the gas strut from the tailgate of a car.

Yep that is one of a couple of thoughts I already had.

simple using proprietary parts has to be the way to go….

Me 🙂

Looks a goodun.

stroke?
spring type?
how does it “latch”?
what did you use to stop rotation?

Mulling the above points over before I start drawing…

5.3″ of travel (6 height options, not infinite adjustability)
Coil spring
Latches with a pin coming from the “pin holder” (big block on outside of post), through both posts, and into the back of the pin holder. Pin is sprung loaded, and withdrawn by the cable.
Rotation is stopped by (or more accurately, limited by) a semi circular piece inside the “inner post” which mates with another semi circular piece inside the “outer post”.

@ Duane…

You read my mind more or less…

I think just to try something a bit different from yours I might go down the Gas strut route, and I’ll start with a plain index pin, move on to a remote at a later date once I’ve got the basic post sorted…

I do like a good bodge… 😀

you may like a good bodge andy but in my experience you aren’t capable of producing one 😆

Your suggesting I substitute, fiddling with mechanisms and playing in the garage for a bit of practical retail therapy…

I’m not a girl… Quote of the week.

People used to use those titec 2-part seatposts and the spring out of a Boxxer IIRC?

I was thinking about something similar at weekend, nothing to stop rotation tho (AFAIK).

Surprised no one has considered reproducing the hiterite for minimalist tightwads….such as myself 🙂

you may like a good bodge andy but in my experience you aren’t capable of producing one

If it involves packaging tape then I’m the lord of the bodge!

surely you just blank off the open seatpost and a lob a boxxer spring in the frame rather than use a scoper post?

that said if you had a decent length outer post you could cut a slot in that then fix a pin in the bottom of the inner post to sit inside the slot. and that would sort the main rotation issues and allow you to fix a max height for the post. the spring does the height thing. then all you need is a locator pin at the top like the rase post (or duanes above)and a bucket full of grease to keep it all moving.

furhter to that if you can get a skinny gas strut to fit inside the inner post then you can blank off the base of the outer post and you have a single unit.

easy.

i also recon you could basterdise a shimano trigger shifter to pull enough cable to actuate the locator pin. you just need the thumby bit and you can remove the indexing inner to the shifter. gripshift would also work but would look a bit funny.

hmm however you would probably want the locator pin to go through both sides of the inner and outer posts as hte load is pretty high and that could be alot of cable to pull…

Oh and an ejector seat . It MUST have an ejector seat.

I think my trance came with one of those fitted for free…

Seems to me the easiest way to stop rotation would be to have the top part of the post oval rather than round, I can’t see any reason it has to be round.

I made mine for my A Level DT project. The main aims were to get larger travel range than most posts available at the time (2-3″), be cheap, and easy to maintain. Therefore, as few parts as possible, and no gas (so it can be taken to pieces easily to be cleaned).

akira – I’d Agree except you then need an Oval or other shaped bush to run it in, oval/eliptical profile is good in terms of no sharp edges Hex bar is a posibility or you simply mill a slot and use a pin or ket of some sort to guide it, but you’re still going to need some type of bush for this all to slide in… Round section is far easir to turn of course, so it’s the default, not unlike regular seatposts…

I heard of one of the Athertons using a Boxxer spring on the outside of the seatpost (Take off seatpost, slip on spring, re-insert) and the qr clamp, like a blingy Hite Rite. If you cut the spring to the extension you usually ride at, I reckon it’s a good un. Simple and should be cheap to try out.

Duane’s does look pretty badass, it must be said!