RECYCLED
RECUMBENT!!!! 
Guide to Long Wheel Base home built bike!!!
RECYCLED
Guide to Long Wheel Base home built bike!!!
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New and old BIKES BY OTHERS!!!!
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Drawing
"Sheets" 1-10 are the EZ Clone - use the button HERE
to go to the drawings
page. Go
here DRAWINGS
to download PDF versions of each drawing. SHEET
1 -
Donor bikes – Church rummages are my most frequent source.
Some people that have great luck roaming the streets on ‘Garbage Day
Eve’ every week. Police
Auctions seem to be getting less frequent, and the Salvation Army here doesn’t
seem to appreciate bicycle gift donations…..
If
you have choices you can make about what bikes to use, focus on three things.
One
– Steel tube bikes, or chromalloy.
Avoid (unless you have the welding skills) Aluminum frames, and oversized
tubings (anything over 1" and 1 1/8", which are typical for those old
road bikes). I generally like the
lugged, brazed frames over the welded ones.
If in doubt, check it with a kitchen magnet. Two
– hardware.
I look at the crank – you want a three piece cotter pinned or
cotterless crank bike – at least for the donor you use as the front end of the
bike. The cotterless crank
with the narrower (roughly 1 5/8” Dia) bottom bracket, offers you the most
choices later for upgrading hardware – different cranks, sealed cartridge
bearings, and so on. The other style
of crank is a one piece – the bottom bracket is much wider, you can usually
see that the crank arms sort of ‘curve’ into the center spindle with no
connecting hardware at all. I tend
to move on and not acquire these one piece crank bikes. Three
– weight.
Steel bikes come in an endless variety of tubing thicknesses, all of
which contribute to the overall weight of the bike.
If it’s a boat anchor, move on (the old Schwinn Varsity is a HEAVY
bike, for example). If the
prospective donor bike is a featherweight racer – well, the odds are that a
first time metalworker will have a hard time with such thin tubing – it is
your choice whether or not to try it (it would make a very light frame....).
Reference
for new mechanics.
Brad Graham's book, "ATOMIC ZOMBIE'S BICYCLE BUILDER'S BONANZA",
has a superb section early on about how to strip a bike down to it's bare frame.
His website (http://www.atomiczombie.com/)
is now about ordering the book - who can blame him, but your library might have
it by now - if not, ask them to get it.
ATOMIC ZOMBIE is worth a read for the new mechanic (and for
alternate building inspiration!). If
you read that and are following along here, DON'T chop the frames up the way
Brad does - it ain't wrong, but it is not the method detailed here. See the picture for cutting off
seat stays on Picture Page 1. Also note that the dimensions
given for cutting are rough guidelines. See the rough layout I
show in the third picture down on Picture
Page 1? This rough layout, for Assembly #1, is the key to a
great bike. When you decide on the final cuts for the front end,
make the front ‘triangle’ as small as practical. Use a stray
crank in the test layout, and a fork inserted in the head tube. Keys to
the layout - the crank arm and the front wheel shouldn't cross, and the 'up'
tube in the triangle needs enough room for a front deraileur to mount later. The
cuts in the drawing, giving you about a 12" 'downtube', are a layout
closely resembling a Tour Easy (commercial bike). I say make it as short
as the layout allows! Typical
for me on an EZ Clone now averages 9-10” – much depends on the actual length
of the head tube of your donor bike. Where possible I like to re-use
the fork and head cups/bearings from this first bike on the finished recumbent.
Matched parts and all that. It
isn’t critical, but it may be easier.. SHEET
2 -
Same notes on donor bikes, except you don’t need to worry about the
crank from this bike. It helps
if donor bike #2 is a really tall frame, we use all the length of the old
seat tube here.
I strip the paint off of all bike frame parts I salvage - after I make
the critical cuts. You don’t want
to weld/braze over paint, and you’ll burn existing paint beyond recovery
anyway. I use a torch in a well
ventilated area to toast the old paint on bike parts, then I wire brush them
clean. Please be careful, and do not
breathe toxins. Sandblasting
is safer, and nicer if you have access to it.
Eventually, you can safely sand or wire brush all the paint off.
You could choose to strip paint about 3” past each of the joints we
make on the bike, leaving the old paint in place.
Painting and matching to those old colors (of the TWO donor bikes) will
lead to some interesting challenges, I think. SHEET
3 - The
first assembly is the easiest – no alignment to do.
Do that rough layout before making the final cuts and the fishmouth
mitre, etc. The most difficult cut is the fit for the old seat
tube under the top tube. Pre-assemble
the sleeve joint with the top tube offset slightly over the old seat tube, and
mark the angle of the intersection.
Cut carefully at this angle, but 3/8” longer than you need it (there is
a picture reference for this cut on Picture
Page 1). Then file a
‘fishmouth” onto this end, removing material towards and away from the head
tube in a curve to meet the underside of the top tube as closely as possible.
File and fit, file and fit, until you get it right.
The down tube is a spliced sleeve joint. Usually a small
piece of salvaged top-tube, smaller in diameter than the down tube, makes a
perfect inside sleeve for the joint. Braze
or weld these two joints. Be
sure to flux and heat the sleeve joint thoroughly so that braze material
penetrates deep into the joint.
The second assembly is easier to fit, and harder to align.
For most common donor bikes, the top tube of the front donor bike will
sleeve nicely into the old seat tube of the ‘rear’ donor bike.
Length factor? – you. I
am an average 6’-0” person, and about 39” long for a top tube is generous
for me. A frame for a truly
5’-0” and slightly smaller person might have a total top tube length of
30” - this is probably a minimum.
A tall person – 6’-4”, say, might want a 41” top bar.
There is now a rough chart on Sheet 3 for length of the top tube.
YOUR COMMON SENSE is your best guide.
Trim the old seat tube from bike #2 to adjust overall length and the
inserted overlap. For
really long frames I have even spliced in an extra length of 1 1/8” tubing
here.
Before welding/brazing, lay the unbrazed assembly flat on a table where
you can weld. Make sure the head
tube and bottom bracket aren’t on the table interfering with the tubes lying
flat, and use washers to shim the front (narrower) portion of the top tube and
the (Bike #2) cross bar so that everything is parallel on the table.
This really is your first critical alignment - take the time to jig and
shim this into shape. Walk away from
the table 6' to the rear of your bike on the table, squinch down and sight along
that top tube splice. Is it
straight along this foreshortened view (same way a carpenter looks at a board)?
Look at that rear 'downtube' in this view - sight over it to the 'first
assembly' front section of the bike - are they in plane together?
Small differences are visible in this 'away from the table’,
foreshortened view. Fix what you see
with shims (washers, automotive feeler gauges, matchsticks).
Over correct, come back, look again.
Take the time to get it right.
The down tube at the bottom bracket and the downtube at the rear of your
frame must be in plane with each other.
Now braze away! When
done brazing, check again to see if you kept it straight (the welding process
sometimes warps the tubes). If
it needs correcting - well, I usually put it on the floor and step on the weld
to straighten it out. I told
you – sophisticated tooling here. Watch
out for a hot foot. SHEET
4 - Try
bending the rear triangles salvaged from both bikes. I
guarantee you will like one of them more than the other one after bending (do
this before stripping the paint off the chosen part).
I use the torch to heat both top stays at the same point (on the
inside/underside of the seat stays), and then I press the bend in by hand down
to the height shown. Here is a
picture series on a jig I made to help on this bend.
Triangle Bending
Jig You don't have to make a
jig. Scrap one of your donor
rear wheels - cut out all the spokes and use the hub to bolt into the two
drop-outs of this separated rear triangle.
If you can find a bit of 4" steel pipe, use that to wrap the bend
around.... Apply heat, and
BEND the top stays. Once for
practice, try the other one with what you learned the first time.
Now look and choose the best one for your bike.
The top ends of the top stays are heat-bent as well.
Test how they might fit at the attachment point (where the old saddle
clamp was) first - you may or may not need this extra bend.
I hold the rear triangle in a vice with seat stay ends sticking up (Picture
Page 2). Heat the stay about
2” down on the outside, and then bend it out about 10 degrees (I use a
18” piece of conduit as a bending lever).
Do the same on the other stay.
Then heat the inside of the first stay at a point about 3” down from
the end, and reverse the bend 10 degrees back.
This brings the original bend back parallel to the center axis.
Do the same with the other stay –this should align both stays parallel
to the top tube you are about to attach them to, and just at the right width to
press tightly to either side of what was once a seat lug.
Have the cut-off seat tube end from bike #1 in hand (from your trash
pile) to test this as you heat and bend. You
may have to come back and fiddle with this bend again - as you mechanically
assemble the rear triangle to your bike and make judgements about alignment, you
will want to fiddle with this bend.
The THIRD assembly, adding the rear triangle to the bike, is the
trickest to align and the most telling on the finished bike.
This can be jigged and
measured for your assurance – there are very fancy alignment tables and
micrometers for just this purpose. Fortunately,
the EZ Clone geometry is very forgiving for rear triangle alignment – a
thorough set-up and visual inspection will do for alignment.
I set the existing partial frame perpendicular to my work table and
upside down. Then I set-up the
rear triangle on the table, shimmed up (on 3/8” spacers) and already in place
with the top stays pressed onto the bike’s top tube.
I’ll put that salvaged rear hub in the rear drop outs, to maintain the
spread of the rear triangle properly.
Then I stand off 6-8 feet and eyeball the resulting alignment from front
and back. In the drawings I
suggested leaving that rear ‘downtube’ long – this makes a great visual
sighting guage for seeing that the rear triangle is in correctly placed.
From 6’ away from the table in front of the bike – is that rear
triangle equally spaced on either side of the very apparent center line of the
bike? Be picky, adjust it.
Go back and look again. Over
correct. Look again.
Now go 6’ to the rear of the bike and make the same foreshortened
sighting of the rear triangle? Like
it? No?
Adjust. Go back to the
front and check it that way. Take
your time with it, and know that we will revisit alignment one more time before
we finish.
Now stand off to the side of the bike – hold the drawing upside down
and nearby – does it look like that?
Top tube and top stays parallel and aligned?
Check the other side.
The old world bike builders use string to check alignment on the bike.
Tie a string to one rear drop out.
thread it through or around the bottom bracket at the front of the bike,
then tie it at the other rear dropout, keeping the line taut.
At your rear downtube, measure the distance from the string to the tube -
one side, then the other. The
two measurements should be equal.
I'll spend an hour with a
bike at this point, moving between alignment techniques until I am happy with
it. It’s worth the trouble.
Weld/braze the top tube and the stay in this position on both sides,
along the 1” or more point of
contact between the two parts. Both
sides, then flip the bike over and weld/braze on top of the joints. Over
do it, fill the gaps - this is where the weight of the rider bears most.
After this assembly, prior to adding the bottom rails, I have taken to putting
the unfinished bike in a stand and mounting a wheel in the rear drop outs.
Check your alignment now - is the wheel in plane with the frame?
Tilted up to down? Hand bend the stays a little - you can do this cold
with the handle of a hammer for a lever. Out of plane front to back?
Leave the wheel in the frame, put it on the floor on it's tilt-to side, and
gently step on the newly brazed joint to adjust. It sounds weird and
crude, but it works. Get satisfied with alignment now, before we
lock it in by adding the bottom rails in the next step.
There is (for me) a ‘ SHEET
5 - Bottom Rails.
You can use something finer and lighter than EMT tubing if you want to.
I don’t mind. Before
doing the final assembly, check out Sheet 6 about bell-forming the ends to join
over the donor bike stubs. Those
stubs are often oblong and strangely shaped (sometimes crimped) depending on the
stays from the donor bikes used, and the bell shaping idea allows you to cope
with all those variations. Test
assemble one bottom rail. When
you like that, repeat it for the other one.
A well formed 'bell' joint IS, in fact, just like the lugged construction
of your donor bike - heap big strong joint for braze welding!
(NOTE – If you are welding electrically, you may want to redesign these
joints.)
The 5 degree bend is useful for spreading the rear triangle slightly.
As you assemble the frame with the ‘open’ bells, rotate the bend out
slightly and evenly to align the bottom rail with the bottom stay on the rear
triangle. When you have what
you like, clamp the two tubes tight against the downtube.
“5 degrees” is a rough number, bend your rails to a degree that looks
good to you.
Stand off to the side. Like
it? Look like the picture?
Adjust while you can. Stand to the rear. Remember
that wheel we put in the drop outs – leave it there while you do this.
Is alignment still OK? Fix it. Like it? I leave
that old wheel (no tire) on the frame throughout the process of adding these
bottom rails. Right up until the point where I braze the final joints,
I continue to stand off and check visual alignment.
Braze weld both rails to the downtube right now, without closing the
bells. This locks the rails in
position. Now heat and
bend/form the bell ends over the bike frame’s stubs.
Do this thoroughly and carefully on all four joints – leave no gaps
where the edges of the bells lap over the stubs of the donor bike.
After you have all the bells formed over the stubs, walk back and take
one more look at alignment – this is your last chance to adjust it.
Once your braze the bottom rails in, the frame is ‘born’ – you have
locked in it’s essential character for life.
Clean, wire brush, and flux everything.
Braze all joints thoroughly, from top and bottom.
YOU FINISHED THE HARD PART – THIS IS (almost) THE FINISHED
FRAME!!!!!!!!!
A note on EMT. You are
burning noxious chemicals off of the EMT as you heat it - zinc galvanizing to
say the least. Ventilate
thoroughly – do not work in an enclosed space.
Do not do this for a living – not a good idea at all!
It’s
a good time now to cut off the extended stub of the 'back' downtube flush below
the bottom rails. SHEET
7. Time
to admire. Does your frame look good
to you? Still like that rear end
alignment? What is right?
What is wrong? What can
be adjusted? Like it enough to
finish it? Sometimes there is an
alignment boner I can fix with cold bending, sometimes not.
Sometimes an error in proportion.
Is it fixable or not? Sometimes
a gap in a brazed joint – those you can fix by cleaning and reheating/brazing.
Now is a good time to decide whether this frame is worth taking through
the rest of the process of becoming a great bike.
Now and again one fails my inspection at this point, and becomes scrap.
Depending on the donor bike and the bend in the rear triangle, usually a
26” wheel is the easiest fit with the existing brake bridge on the top stay of
the rear triangle. Sometimes a
27” wheel will fit. If you
really want a 27" – cut this brake bridge loose now and add your own.
Or add direct pull studs, etc.
C. The chain idler is
not really necessary. It helps
carry the weight of the extra chain which is otherwise pulling on a deraileur
spring that wasn't designed to hold it, and it keeps the chain (potentially) out
of the dirt. I drill a piece
of ¼” threaded rod through both bottom rails of the bike in the position
shown, and mount an idler wheel salvaged from a rear derailleur on it between a
couple of 2 ½” plastic washers.
NOT SHOWN - I usually run the very long rear deraileur cable along the bottom,
right hand rail, much the way it is run on the typical 10 speed road bike.
I add one extra (usually salvaged) cable stop braze-on, just behind the rear
down tube and ahead of the 5 degree bend on the right rail. This acts as a
slight mule block for the rear deraileur cable and keeps it from fouling the
chain. SHEET
7A.
This is just pretty. To me,
anyway. Gives some
idea of how a human fits on the bike. SHEETS
8-10. Parts.
This is the sling seat I use. I
can and have put a Rans seat on this bike, and even an Easy Racers’ Cobra
seat. You can make a plywood
seat, put foam and fabric on it and
do just fine. I like
this one a lot – I rode 150 miles on it with a broken tailbone, no less!
But that's another story. The
secret of bending that really odd shape is to mount a conduit bender in a table
height bench vice. Then bring
the ½” EMT tubing, thoroughly marked, TO the bender.
½” EMT bends pretty easily by hand, yet is rigid enough to stand up to
this 270 lb. rider without deforming.
Bend the 45 degree end first, then bend the 90 degree "bucket"
for the seat. Take care in the
bender to visually align each bend on the same axis at the first bend.
See the green outline shapes on the drawing?
On the PDF sheet DRAWINGS
are the four pages to print that will give you this shape full sized.
Print the pattern and use it (or alter it) if you like.
Buy extra conduit, make extra tries at bending it just right.
Conduit is cheap (well, it used to be) – make four (4) side rails and
choose the best two for your seat. A
full sized pattern is a help.
Seat cross braces. I
make the bottom brace from ¾” EMT – this part bears the rider’s weight
over the bike's top bar. Do
draw a full scale pattern for this (more pdf files you can print – DRAWINGS).
Lay your finished, bent brace in this pattern before cutting to establish
exactly where to cut off the braces.
Have an extra 24” length of 1 1/8" bike tubing handy to use as an
extension on the EMT you are bending – you will want the leverage.
Seat covers. I use a
vinyl mesh fabric – Power On Cycling sells a very good mesh for seats in small
quantities. I hear there is a
great rip-stop nylon fabric for sale at REI that works too.
I stitch my covers on around the seat rails with nylon monofilament.
Looks great. Go to this
page SEATS
for a blow by blow on seat covering. It
is possible to stitch and grommet a separate cover and lace it onto the frame.
Or to do what Rans and others do in the way of a cover that wraps around
the the back of the frame and then is cinched with zipties. SHEET
9. Seat stays.
This item, bolted onto the extra holes in a rear drop-out, is a fairly
good, lightweight way to hold up a seat back.
There are other ways.
Like this: A 5/16” steel rod from
Home Despot sleeves very nicely into a 3/8” aluminum tube from the same
source. Flatten one end of the
tube and drill and bolt onto the drop out.
Weld a nut onto the end of the rod and invent a pivot bracket on the back
brace of the seat. At whatever
adjusted height you like for the seat, drill through the sleeved rod and tube
and set a cotter pin. Simple. My
seat stay works pretty well – you can screw the bracket up and down the
threaded rod (within limits – you don’t want it poking through the seat
cover). For a shorter riders
you can add threaded sections onto this stay assembly to extend it forward.
For riders that want to lean back farther - cut off some threads! Seat
bottom bracket – simple, effective,
easy to make. This and four
hose clamps and I have all the adjustability I need. Steering
Stem.
This is what I make, for two reasons.
One, I am cheap. Parts
are virtually all salvage, and a 1” handlebar stem sets very well inside
standard ¾” EMT tubing. Two
– this stem is infinitely adjustable.
I can make it very long for my comfort, or cut it off easily for a rider
with longer reach.
The bent-over flaired stem from an old racing handlebar crimps quite
badly when heat-bent this way (heat the inside of the bend, not the outside).
But when you heat the crimp up and fill with brazing rod, it gets quite
strong. SHEET
10. The bike uses the original fork,
which has a brake mount in the crown where you won't need it.
You are going to use a 20” wheel (You can use a 16" wheel instead
- try both and see what feels best to you for handling), so you need to set a
new bridge in this way. Fancier
alternatives? You could buy and set a manufactured bridge in the same
spot. You could buy parts for
cantilever brakes and mount those. I
haven’t broken an EMT bridge yet. ASSEMBLY
Notes
on parts. Again, I don’t
here go into the nuances of bike components and assembly of your finished bike.
You can salvage the 10 speed (or whatever) gear train components from
your donor bikes and apply them to your new bike.
I do this, with the best components at hand, for every 'new' bike I make.
Rely on your ingenuity to string cables and guides for the deraileurs and
brakes front and back. The
chain line takes roughly 2 1/2 standard length chains. You
should go all the way through your assembly and test-ride the bike before you go
on to finishing and painting. You
might want to braze on a cable stop, or file away a clearance, and so on.
Assembled?
Time to test it, see what you like, see what you want to adjust.
Deep breath, and push off! Get
happy for a week or so, be patient.
When you have it how you want it, now is the time to strip it all down
again and finish and paint!
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