Recumbents and all feet forward machines
Thought I'd say hello and show off my home-built recumbent trike, built using almost entirely scrapped, found or donated materials. This project had 3 main goals:
1. Teach myself to weld. I did some basic welding in a tafe course many years ago, but I was pretty terrible at it, so even now my welds are solid, but ugly as sin. That said, I'm in the process of building a smaller trike for my 8yo son, and they are slowly getting better.
2. Give myself some low-zero impact exercise for my hips and knees, while keeping my weight off my shoulders. I have an auto-immune condition that makes even light impact (such as walking for more than about 1/2 hour) pretty painful, coupled with arthritis in my shoulders. A recumbent trike seemed an ideal solution, but due to disposable income considerations, saving to buy one would take much longer than building one, even if the result looks like it should be in a Mad Max movie.
3. Give myself a project for mental health. Before my joints fouled up on me, I was a chippie, and I love building things (especially things a little outside the box). I now work very part-time, and the lack of things to occupy my mind/time was depressing me.
The only items (other than some new tools) I had to buy new were the chain and gear/brake cables, and I also had to buy two second hand (ancient) bikes to find almost matching kingpins, though I later bought some lights and a flag for visibility. Once my boy's frame is completed, this one will get stripped back for painting.
So anyhoo, without further adieu, here is my prototype, the "Grizzly" (so named after the design issues I encountered during the build process)...
... and what first post would be complete without a question or 2?
The idlers were sourced from an old, incomplete trike built by the students at a high-school, and I have no idea where I could find some for my son's (or future) trikes. I'm currently planning on putting some chain-grooves into nice fat skateboard wheels, but I'd prefer proper idlers, if anyone can provide a source?
Also, I'm planning a third build with rear suspension for day-trips or possibly camping, and am considering a larger rear wheel, but I prefer the look of like-sized wheels. Does the larger rear wheel add substantial comfort, given that this one would have rear suspension anyway?
Comments and suggestions would be welcomed
You have a very wide front profile, in other words the crossmembers that you've used between the two front wheels are long. I'd be tempted to look for ways to use this space to stow things but I would normally prefer a narrower profile for our bikepaths. What you've gained in stability you've about lost in handling.
I've bought idlers from Greenspeed, other trike makers or shops should have them so Trisled and others. The last lot I made myself, a bit like you are now doing with skateboard wheels except that I found raw materials as well as the usual bearings at a bearing shop plus had access to a lathe.
I prefer also the same sized wheels on all, for handling and maintenance as well as not having to carry different sizes in spares. A larger rear might give comfort but alters the handling, doesn't respond as well to having a cargo on top when cornering. Lots of things would work better if we all just went in straight lines. The other thing I noted with your trike is that you have a knobby rear tyre, surely you feel that through your seat?
Yeah, the track is just over 40" if memory serves. During construction I'd left them oversize, and planned to cut them down for a 32" track once I knew the angles the kingpins would sit at, but it took me a while to find (near) matching kingpins, and when I did, I got all excited to continue building, and forgot There are a few tight spots on the local paths, but I can get through most places. My future builds will be narrower, with my sons planned at 32" track, and the tourer at probably 30" or a tad less.
I looked for idlers on Greenspeed's site last night, but couldn't find them. I might give them a ring, as my "search-fu" is weak. Trisled I'd not heard of till I browsed here a bit, so I'll check them out too.
I'd also not considered how a heavy load would affect a larger wheel. Now that I do, I wonder what effect it would have on suspension too. It might need stiffening to the point of near uselessness.
As for the rear tyre, I've noticed a fine vibration at low speeds on a sealed surface, but most of the bike-paths nearby are pretty rough anyway, and with only the rear brake, I'm reluctant to do too much "on-road" riding at this stage. If I find some "budget suitable" disc calipers, I may swap out the knobbly tyre for something smoother. In the meantime, locking up the rear wheel and spinning out amuses my boy no end (and me, to be honest), and that kinda makes it worth sticking with till it's worn out
A pretty god effort there. I've built several different ones. One was from AtomicZombie. It is a delta. They have some tadpole designs too. Might be worth a look. The builders forum there is very helpful.
Three same size wheels is good because only need one size in tubes etc.
Here's another good site for info. Tim lives in Devonport Tasmania.
This is good for working out your steering.
Idlers: I have used rollerblade wheels satisfactorily. I have also built them from scratch with ball races and some nylon rod turned on a makeshift lathe. Both work fine. If you Google Dutch Bike Bits and find David Hembrowe's site he has idlers for sale at a reasonable price.
When I built the Tadpole trike I used ordinary rim brakes. They are quite satisfactory. Independent levers and one on each wheel. A rear brake on a tadpole can be dangerous. You should be able to see how I did it in the thread below.
Hope the above helps with your builds And look forward to seeing your son's build.
Thanks John. Yours certainly puts mine to shame, though other than my poor welding skills, the "Cub" is looking pretty good, and I assume as my experience and collection of tools improves, so will my build quality. Uba Tracker's comments in your thread regarding Arc Welding and the black arts made me feel better though. Glad it's not just me that finds it hard to get the hang off.
The steering geometry I have a sound knowledge of, (I've build R/C aircraft for many years, and the travel on servo arms is the same theory as the ackermann arms, so it came pretty easily to me, but the effects of caster, camber and toe-in were new to me) and I visited both those sites during the research phase of the build, so it's just the precise construction that eludes me at the moment. That said, the Grizzly steers well, (though I really have nothing other than the carts at the local go-cart centre to compare it too). However, due to a minor mishap during a stress test resulting in a slight bend in the right crossbar the right wheel has more camber than the left. This doesn't seem to have any ill effect on the steering though, and after re-aligning the steering there's no (detectable) scrubbing. The reinforcing struts running from the front of the seat to the kingpins were a result of this mishap, and it's since seen some very rough treatment with no further defects found
The Cub follows the same design, if more refined, and it will have a few modifications to improve safety, given the age of the intended rider and his lack off riding experience. I think I'll steal your front brake design for a start, though I'd like to run them both from a single brake lever so he can have rear brakes as well
I may add a seat belt of some sort too, as I can easily see him tipping it forward, and going over the front in an emergency stop...
For the rollerblade wheels, did you remove the "tyre" or groove it to take the chain? Seems these would be the cheapest option given the number of kids toys I see them on at places like K-Mart. I still have no access to a lathe though, so buying ready made ones is the most likely solution at the moment, unless the removal of the tyre part of a rollerblade wheel does the trick. You "makeshift" lathe intrigues me though. How did you "makeshift" a lathe?
I'll add some WIP pics of the cub on Monday, as I had to pack a bunch of stuff up. Seems we're heading down to Geelong tomorrow for the HPV gathering (with front wheels and the steering linkage removed to allow the handlebars to move independently, the Grizzly fits in the back of the wagon! Yay!!!)
EDIT: I borrowed my wifes iPhone for a couple quick WIP shots of the Cub...
The frame in its current, naked state.
The boom holding the BB is not fitted yet, as I only got the seat frame attached yesterday, and want to get the boy seated in it to check the length to allow for as much growth as I can.
One of my off-siders, clearly unimpressed with being photographed...
And a random shot of the inaccuratly named garage (it's not had a car in it since we moved in). It's not as cramped as it seems here (I'm standing in the main work-space), with my tools put away, I can easily park 2 or 3 trikes in here.
Last edited by DentedHead on Sat Oct 27, 2012 10:19 pm, edited 1 time in total.
My arc welding skills require me to weld, grind, weld and so on until it looks good enough. I do much better with the brazing. I learned by trial and error and much practice. The best thing I bought was an auto darkening helmet. The next was the little DC welder to replace the Bunnings Buzz Box.
You can get a 2 into one brake lever from Trisled or cobble one up. I think Tim Smith shows how to make one on his site.
When you make an idler from a skate wheel you keep the tyre on and groove the tyre. It can be done by putting it on a bolt, fitting the bolt in a drill press or even a hand drill held some way or another. You can use the sharpened tang of an old file or a small chisel and with care it grooves out nicely. You need some kind of rest. If using a drill press you can clamp something or use a bolt through the table.
Heres a way that a "lathe" can be cobbled. probably not suitable for idler though.
http://forum.atomiczombie.com/showthrea ... an-s-lathe
Here is how I did a toothed idler. I show my Gingery Lathe that I built and it was used for this one. Prior to that I had a cobbled together job and I resurrected it to show what it looked like. Where there is a will there's a way.
http://forum.atomiczombie.com/showthrea ... r-in-Nylon
The nice thing about DIY is you can chop and change and modify by trial and error to your hearts content.
Have a great day down at Geelong. I'm way to far away to join you.
Sweet, I could rig that up easily. I'll need to buy a drill, but that was next on the tool list anyway (the Grizzly needed only a single hole to mount the rear brake, so I'd simply ridden it down to my inlaws, borrowed my father-in-laws, and did it there and then). I also have a plastics place down the road I'll bet would have Nylon rod... self-made is looking more likely
Why do all the drive side idlers have teeth? I assume its to ensure the idler moves with the chain, rather than the chain sliding over it? Return idlers don't seem to have them, so I'm pondering their worth...
They don't necessarily. The drive side one on my mango is just a groove. It has an O ring in it but I don't think that will last long.
The one on a friend's SWB bike is similar. His O ring cut out and I replaced it with a rubber ring from the irrigation place.
Great pics. That is coming on well. Looks like you can at least move in your garage/shed. mine is in need of a good clean out. Its a disaster.
The Greenspeed website isn't the greatest for finding parts, you need to either download or contact them to send to you their full catalogue. In that you'll find their idlers as well as 2-in-1 brake levers and other bits.
The WISIL website has lots of builders info including a couple on idlers http://www.recumbents.com/wisil/idler/idler.htm
And in my previous post I forgot to say 'well done'. My first recumbent eventually folded in half as I'd built in mild steel without adequate reinforcement, these are the learning times. Show us more.
I'm pretty set now on making my own idlers, seeing how easily it can be done (once you have an inkling how to go about it). For now, I'm going to go with Rollerblade wheels untill I can either knock up a makeshift lathe, or find a smallish "proper" one, but from then on, I'll turn them up from Nylon rod, a' la John's example. I'm lucky that I have an awesome tool shop 3 mins walk away, and plenty of industrial estate nearby to source stuff like nylon rod, bearings, etc (Cro-Mo seems to be the only thing that's near impossible to get, but there's always plenty of bike frames at the local tip).
Funny you say that, as that's the part I dislike the most, even though the simplicity was the reason I took that path. For the Cub, I managed to find a pair of kingpin/forks that have the inner part of the kingpin extend down and was able to cut and file the forks clean off, but the Cub also has a better axle arrangement to begin with, with the hubs coming from old wheelchair wheels(they're even quick release, though I think once I mount brakes, that might become redundant). That said, the Cub has had more effort put in to making it prettier from the start, as it's my Christmas present to my boy, and needs to look as nice as I can make it on my limited budget.
Cheers, after a bit of looking around, I found the 2-in1 levers, and given how nice they look, I think this is one part I'll have to buy. While I like the method on Tim Smiths site and will have a go at it for my touring trike, I have doubts on my ability to make one looking nice with my current tool set.
I discovered this morning that my mock-up of the BB boom will not work, as I've flipped the BB upside down, and would have had the chain ring on the left... Good thing I left it unattached to double check my boys "leg length" before I welded it on. Fortunately, all it means is the bracing post will be welded directly to the BB (once I right the BB boom), rather than slotting into the tube I'd removed earlier. I'm also considering putting a skid type arrangement under the BB to protect the chain ring in the likely event that he tip's it forward in an emergency stop.
Alas, no further work done today, as after our trip to Geelong, and the subsequent ride once we got home (he was itching to hit our "square lap" as we call it after the drive home) I'm too knackered to take to the remaining welds with the file, and even if I could reach the remaining welds with the grinder its too late in the evening for power tools.
I had my first long(ish) ride yesterday,about 40km's all told. My friendly local bike shop has a cafe, so tootling down there for a late morning coffee seemed a good excuse for a ride (10.1km). Once there, it seemed too nice a day to just ride back home, so I called a mate, and we agreed to meet at Lake Wendouree. He was going to be a while, so I cruised down to the main street and dawdled up to the lake (3.2km) and I rode 1/2 way round to our meeting place (approx 3km). Once my mate Dave arrived, we did 2 laps of the lake (approx 12km). By then I had to head vaguely homewards to collect my boy from school, so Dave packed his DF back into his car, and I headed 1/2 way back around the way I'd come (again, about 3km), then back up the main road to home (4.7km). Naturally, after hearing I'd been riding around for a couple hours, my boy wanted to go for a ride too, so we headed out and rode about 4km (ish... we sort of meandered a lot, so that's an estimation).
I know 40k is peanuts to anyone used to riding, but I was surprised at how well my legs handled it, although I totally forgot to put sunscreen on my legs (I almost never wear shorts) and today I have "lobster shins". I'll also admit, my hips are feeling a tad stiff today, but I reckon it's nothing a lap or two of the lake won't fix...
This got me pondering... it's rare to have more than about 50kms between towns here in Victoria, at least until you head further west. I'm considering a "weekend tour" some place. Ride to a nearby town (such as Daylesford), stay the night, and ride back the following day.
Yeah, the ride around the lake is particularly nice. I did 3 laps this morning to loosen my stiff-ish legs after yesterdays ride. I've not ventured onto the road a great deal, sticking mainly to bike paths, but when I have been out amongst the traffic I've found Ballarat drivers to be surprisingly courteous. I guess they had to have at least one good thing going for them
I also did a little tinkering this arvo, and went for a night-ride around the lake this evening too to test my modified seat set-up and check my gearing (always seems to work different in the garage than it does on the move). Fantastic ride! I did find that being lower down makes it seem like every car has it's high-beams on though (there is a road running right around the lake too). I need a brighter head-light for future night rides.
I have a 50km trip to Daylesford in the planning stage, just looking for the right time for it. Ideally, it would be a long weekend, so I can ride out there day one, meet the fambly (who would drive, its a bit far for an 8yo and Mrs Dent, who has yet to acquire pedal-power of any sort), hang out there for day two, and ride back on the third day. It would also mean I wouldn't need camping gear etc, as there are plenty of great places to stay for a couple nights out that way. Failing that, a two-day trip could be do-able.
In the mean time, I discovered today that Google maps will show me the bike paths that are out of the city, so a 50km "test-ride" will probably happen this Saturday, if the weather is favourable.
And you'll be in the good books if you surprise Mrs Dent with a side trip to one of the spas.
2007 Giant TCR A2 Aliance
1940s Bullock - nice and strong for the boss.
Cargo bike - soon.
I'd be surprised if she didn't already have it planned...
Looks like I'll be in the garage tomorrow (er, today, as its 1:15am now) as the weather looks to be nasty, and my joints do NOT like the cold, plus the rims and spokes for the Cub should've arrived today, so I can get to work lacing the wheels for it.
Good day in the workshop today. Got the axles attached to the kingpins, and the kingpins welded (almost) nicely to the crossbars. I'm sure my buzz-box is playing head games with me. I was all mentally prepared for difficulties and frustration, but all went well. Still not the prettiest welds around, but defiantly an improvement over my last lot. Pics to come once Mrs Dent is done with her phone and sticks them on the 'puter.
Work so far, with BB boom, head stems and handlebars dry fitted, and "place-holder" rear wheel.
And the Cub next to the Grizzly for size comparison. The rear wheel axles are roughly aligned, though the angle doesn't show it well.
Seems I'm not the only one to find recumbents comfortable...
The BB boom has been cut to the longest the boy can comfortably reach with padding on the backrest, as it'll not be adjustable once I weld it on and add strengthening braces, so I want as much room for him to grow as possible. As he grows, I can remove the padding to accommodate his longer legs somewhat, though this will only give another inch or 2. I plan on mimicking Johns rim brake method, (linked earlier in this thread), but both front wheels will be operated by a single lever, allowing him to have rear brakes as well, and steering limiters and linkage will mount off the same bars as the rim brakes.
This made me laugh There's a reason I don't take close-ups of my welds. While getting better, they are still not going to win any beauty pageants. I did find the tips in the tutorial section at AtomicZombie a help though.
The Cub is a little over 800mm wide, narrower than the Grizzly, but intentionally wider than most. I love the stability of the Grizzly, and wanted to ensure the Cub had similar stability, while being easier to navigate between bollards. I think the lack of tyres makes it look wider than it really is though.
Yeah, I like simple, mainly as I have a less than ideal work-shop. As my tool-set and experience grows, I'll begin making custom parts, and some things will no doubt get more complex (at least where more complex = more fun to build).
I'm looking to use some cut-down MTB forks as the brake/steering linkage mount, but I've not yet thought of a way to keep the quick release hubs "quick" once I've brakes mounted around the tyre. The quick release mechanism slides the wheel sideways out of the sleeve that's welded to the kingpin. Having calipers wrapped around the tyre will prevent this, so I'll need a way to easily get the brake calipers out of the way first. This will probably kill the plan to use front forks as the brake mounts. Either that, or live with semi-permanently mounted front wheels.
I pondered them, Baalzamon, but the hubs weren't fitted with them, and it's currently beyond my abilities to retro-fit the rotors. The Grizzly will soon be upgraded with discs, as it has the rotors already fitted, I just lack the calipers, and trike No. 3 will also have discs. The Cub is stuck with rim brakes of one sort or another.
Who is online
Users browsing this forum: No registered users