Woody?

Joined
Jun 5, 2022
Messages
14
I am seriously considering building a wood frame recumbent of some sort. I’ve joined several fora (forums?), bumped into Stormbird (who pointed me here), read a few posts on veloforum.de through Google Translate and even put together a Pinterest board. I need a commuter and one option is a Python tadpole (no prizes for guessing where that suggestion comes from) and I do enjoy riding a trike. I currently have invested in a 2nd hand mismatched pair of 20” wheels and have a garage full of timber as I used to be a carving instructor. I am very short of leg with a 28” inseam and am thinking of something similar to a Toxy SV with a steam bent laminated and hollowed frame with a conventional rear fork, not single sided, and no suspension . Preliminary measurements suggest a 48” wheelbase. I have never ridden a recumbent and part of me wants to do this as everyone in my family thinks the idea ranges from stupid to death trap! Standard reply is, “get a folding city bike”. Anyway, I would very much be interested in your thoughts, advice, links to threads, whatever. I especially could do with suggestions for frame “tube” shape cross-sections and dimensions. Thanks in advance.
Andrew
 
Joined
Oct 19, 2012
Messages
2,384
Location
Wakefield, UK
I think you mean a python delta, not tadpole. Googling toxy sv brings up some weird results. Could you supply a link?
 
Joined
Oct 19, 2012
Messages
2,384
Location
Wakefield, UK
For someone good with wood it would make sense to build the seat in wood too and use it as a part of the stressed frame rather than a separate item.
 
Joined
Feb 7, 2008
Messages
4,575
Location
Nottinghamshire England
Hi all



I think initially yes it would matter as you have no idead what you find comfortable and @ what angle you need for the road to see well.

Also initially you need to consider that the angle between the seat back and the base is dependent on the seat back angle you settle on ?

I had a bike similar to that with for me a to laid back seat , I build a fancy mount to move the upper rear of the seat forwards only to find the base moved far enough for me to slip off the front of it !

YMMV

Paul
 
Joined
Oct 19, 2012
Messages
2,384
Location
Wakefield, UK
I'd offer a different perspective in that I've always set the seat at somewhere around 45 degrees just by eye and never felt the need to move it on any machine I've built. If you can build in wood sufficiently strongly to take all the stress on the one member then a moveable seat is not an issue. Perhaps it's my own inability to work in wood that suggests to me that a single wooden member won't do. I readily concede my woodwork is crap.
 
Joined
May 31, 2013
Messages
3,980
Location
South Benfleet, Essex, England, UK
I too am "inseam challenged" so a Python Delta is not at all a bad option.
I built one and it is a decent machine with many advantages.
 
Joined
Jun 5, 2022
Messages
14
Regarding seat angle, it would be possible to bolt/screw everything together and glue it all down after a few test rides. A Python trike is certainly the better option but I am pig headed and stubborn and the bike is just something I need to get out of my system,
 
Joined
Feb 7, 2008
Messages
4,575
Location
Nottinghamshire England
Regarding seat angle, it would be possible to bolt/screw everything together and glue it all down after a few test rides.
Your first bike won't be perfect , if you try to make it perfect it will never get finished
Also whilst building it you will have better ideas how to tackle something already created !
So aim for it it be ridable and expect to build a second that will be better.

A Python trike is certainly the better option but I am pig headed and stubborn and the bike is just something I need to get out of my system,
Start simple with the bike it will be easier to build !



I have one of these a Flevobike OK-JA a excellent beginner/shopping recumbent notice that the seat is just a bit lower than a normal bike however the pedals are quite a bit higher.
That is where the challenge is for a beginner to get on and ride of , early rides wobbly a little however no one falls off and it is soon mastered.

As the seat gets closer to the floor and more laid back it becomes harder , your legs move from vertical to horizontal and so are little use for balance , the pedals can be come higher than the seat base all compounding the problems



This is about as bad as it gets !

Paul
 
Joined
Jun 5, 2022
Messages
14
I think the reason I am drawn to a Toxy sized frame is because the seat and pedals are a similar height and when I tried a mock-up involving a garden reclining chair set about 40 degrees, everything seemed quite comfortable and I could put a foot flat on the floor with a foot at pedal height without being too laid back

re keeping my first project simple, I do get that, but I need an element of challenge, aim for the stars, hit the moon kind of thing. Read lots, talk lots, aim high. In my ignorance I think a bendy frame is relatively straightforward compared to the Python trike that might be my second project
 
Last edited:
Joined
Feb 7, 2008
Messages
4,575
Location
Nottinghamshire England
I think the reason I am drawn to a Toxy sized frame is because the seat and pedals are a similar height and when I tried a mock-up involving a garden reclining chair set about 40 degrees, everything seemed quite comfortable and I could put a foot flat on the floor with a foot at pedal height without being too laid back
That's the way I started and it helps me as I prefer full size parts in 3D than drawing stuff , just the way my mind works.
I am now lucky in having built something successful and has been comfortable over many miles I can measure directly from that.

re keeping my first project simple, I do get that, but I need an element of challenge, aim for the stars, hit the moon kind of thing. Read lots, talk lots, aim high. In my ignorance I think a bendy frame is relatively straightforward compared to the Python trike that might be my second project
I agree and wish you luck.

Paul
 
Joined
Oct 19, 2012
Messages
2,384
Location
Wakefield, UK
Glad I dont have to ride it would be my first thought. Flevo style engineering looks like an easy way to an injury to me. The bars are going to move quite oddly given the pivot. If Flevo geometry is the way you are going I would think having your body more upright would help in trying to stay on it.
 
Joined
Jun 5, 2022
Messages
14
I’m planning on using conventional fwd, probably with a modified 2nd hand fork. Any comments on the construction?
 
Joined
Jun 5, 2022
Messages
14
I was thinking of going with something along these lines. I’d be grateful for your thoughts, especially about the triangulation of the rear forks. I was thinking of a hollow boom and upright with twin rear fork beams joined by 2 or 3 struts
 
Last edited:
Top