Danny's Daily Delta

Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
Please excuse this placeholder, I am just testing things on the new forum.

The delta is alive and well, but on the back burner while I address some other issues and get ready for Holland 2019.



I made a non-tilting rear section as well as the tilting one and the two are interchangeable.
The change just requires the removal/replacement of the pivot bolt and some spacing washers.
My plan is to learn the foibles and pitfalls of MBB cycling before I add the complexity of the tilting feature.
To this end, I have 2 sets of drum hub backplates and one set of drums with rims and road-tyres.
 
Last edited:
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
Dan

At last something the right way around .....

I'll get my coat :)

regards Paul

ps first picture broke !

Oops! We ran into some problems.
The requested page could not be found.
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
Dan

At last something the right way around .....

I'll get my coat :)

regards Paul

ps first picture broke !

Oops! We ran into some problems.
The requested page could not be found.
Fixed now?
 
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
Dan

Spot on ;)
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
The Delta is alive and well but it undergoing a transformation from MBB to another style of MBB. The serpent-based variety.
Yes, the Delta is being Pythonised.
The PPP (perfect Python Pivot) as documented in another thread is in the process of being put into practical use on this suspension equipped delta.
The mesh seat from the Wonky-Donkey Mk2 will be used in place of the hard shell seat I had previously fitted to the MBB version.



The track of this delta is a little bit wider than I had initially intended, but before I start hacking it about I shall see how it "feels" when in use.
I suppose it is true that a wider tracks provides for more opportunities to carry shopping/tools etc. in something attached across that rear section.



I need to do some drawing-board layout work to see where best to mount the seat and the pivot location.
Then I can establish how the front triangle should be made and where the Bottom Bracket will be placed/positioned.
I will transfer the Sturmey Archer 8 Speed IGH across from the MBB forks to this trike in due course.

That is all.
 
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
I know this is a personal question ?

Did we ever try to ride the MBB with your non-tilting rear ?
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
I know this is a personal question ?

Did we ever try to ride the MBB with your non-tilting rear ?
Yes. Clearly "No One expects...THE SPANISH INQUISITION" :ROFLMAO: But I found it to be alien and uncomfortable to the point of "NO". Far too much pedal-steer and just felt "wrong" from a steering perspective.
However, the front frame & forks remain unaltered should I want to try again.
I suspect a Python will be similarly "gifted" in the pedal-steer department, but I am willing to give it a go before claiming the concept is flawed and not for me.
I am attracted to the self-centering of the steering which ought to mitigate the yawing a little. We shall see.
Even if it is another "Not for me" experience, so what? It will have been a good build experience where I have learnt new things and had some fun in the making thereof. :)
 
Last edited:
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
Don't forget all these delta rear ends could be used with twisting chain FWD...

Of course it won't have any steering foibles , however the chain will always try to shave the inside of your right thigh ? other people pay good money for this in some quarters - so I have been told :LOL:
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
Please excuse the poor quality of the picture, the lines are feint and probably NOT too visible.

The wheelbase is 112cm (as drawn by the 2 circles (front one in BOLD FELT-TIP).
That is the main frame from the MBB. The current "new" frame consists only of the horizontal section and the pivot assembly.
If I want to keep the wheelbase as is, then the Python Pivot will have to come quite a way back (as shown) in order to clear the wheel and then have the drop-outs on outrigger triangle(s) maybe.
The thing that looks like an enlarged "£" symbol in curled up paper is the side profile of my mesh seat.
Alternatively... I could extend the wheelbase by about 20cm (8").

Nor is there anything stopping me from just putting a plate on the front of the keel and bolting the PPP to that and having the front triangle built to suit.
Placing the keel at such a high altitude relative to the axles may make a difference to the Pythonising characteristics, I don't know. We shall see in due course I guess.

 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
When is a 406 sized 20" wheel NOT a 20" wheel?
I was surprised today when I actually measured a 406 rim with a 20" x 2.15" BIG APPLE+ tyre on it.
Instead of the overall diameter/height being 20" it was closer to 21½".
It is a good job that I checked because I am making a front triangle to wrap around the outside of the wheel.
Well I have made a start at least. Some 4mm plate has succumbed to machinery to form some dropouts.
I think I had better be very careful about clearance hadn't I Clarence? I don't want to use the wrong vector, do I Victor?
Did you say "roger", Roger?
 
Joined
Oct 19, 2012
Messages
898
Location
Wakefield, UK
When is a 406 sized 20" wheel NOT a 20" wheel?
Yep - Both nominally 20" wheels here. One is 22.5" and the other 18". If you are having tight clearance issues in a design you really need to know the actual size beforehand. I accept that these are probably at the extreme ends of the scale.
 
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
The wheelbase is 112cm (as drawn by the 2 circles (front one in BOLD FELT-TIP).
That is the main frame from the MBB. The current "new" frame consists only of the horizontal section and the pivot assembly.
If I want to keep the wheelbase as is, then the Python Pivot will have to come quite a way back (as shown) in order to clear the wheel and then have the drop-outs on outrigger triangle(s) maybe.
The thing that looks like an enlarged "£" symbol in curled up paper is the side profile of my mesh seat.
Alternatively... I could extend the wheelbase by about 20cm (8").
Mk1 was 36" Mk2 is 45" ish so you are in the ball park ?

Nor is there anything stopping me from just putting a plate on the front of the keel and bolting the PPP to that and having the front triangle built to suit.
Placing the keel at such a high altitude relative to the axles may make a difference to the Pythonising characteristics, I don't know. We shall see in due course I guess.

Not really the granddaddy of the Python recumbent was the Staiger Airbike ?


All you are doing is building a tricycle version of it on 20" wheels instead of 26" wheels ?



regards Paul
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
Mk1 was 36" Mk2 is 45" ish so you are in the ball park ?


Not really the granddaddy of the Python recumbent was the Staiger Airbike ?


All you are doing is building a tricycle version of it on 20" wheels instead of 26" wheels ?



regards Paul
Thanks Paul, it is reassuring to know it is not going to make it ineffective.
 
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
Thanks Paul, it is reassuring to know it is not going to make it ineffective.
hey don't put words into my mouth :whistle:

Just cos someone made it does not make it good/right ?

everyone raved about the Sinclair C5 ? would you have bought one ? ;)
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
hey don't put words into my mouth :whistle:

Just cos someone made it does not make it good/right ?

everyone raved about the Sinclair C5 ? would you have bought one ? ;)
Safe as houses ......

 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
Today I began making the front triangle/wheel surround/frame.
The 4mm plate I cut into dropouts yesterday was welded to the centre sections of the frame.
I found it easier to melt the bevel edges of the plate into the underlying box section than to try and fillet-weld a 4mm high internal corner.

Here are some pictures of the welds and the final result of the 2 dropouts mounted onto a threaded stud at the correct OLND for my hub.
These centre sections of the framing are oversize and will be trimmed appropriately.













This last shot (above) shows a section (c.10mm) that has not been fully welded together on the right-hand side. I will fix that tomorrow.
 
Last edited:
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
Dan

A nice trick you can do with TIG but not with MIG ;):whistle:

Are you lying a weld on the outside of the rails ? hard to tell.

The left hand weld in the fourth picture down I think shows 2 things ?

Can you see on the left of the weld there is a smooth transition from the box onto the weld dimes ? I think that shows you had a good weld pool on the box section and the 4mm edge sort of slumped into it.
Of the right of the same weld there is a line of fine scallops to the right of the weld dimes ? I think this is an undercut caused by the above slump and no additional filler being used in the joint

If you then look at the right weld in the first picture both these features are missing ? so it looks like there was no pool in the box section to start with ? and maybe you had less current or went faster and there are no slump scallops either ?

I am NO weld expert , that is just how it looks to me from stuff I have gleaned etc etc

Maybe someone who knows what he is talking about will be along soon ?

It is a method I have used in the past and don't think the method is suspect ?

regards Paul
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
Thanks Paul, yes there was some variability. It took me a little while to get my eye/hand "in" as it were.
I started out trying to use filler as well. Then, when I wasn't happy, I looked up at the welder to see that "full-pedal" was giving me about 20A less than I had the dial set to.
I accordingly upped the "indicated" Amps by 20 more and the results were a lot better and in fact little to no filler was required. Despite the variation, all of the welds look really solid to me (in most respects - saving that 10 mm section on the last RH one). I will be having another play tomorrow if the weather isn't too blowy or rainy.

The box section is 38 x 19mm @1.5mm so is rather heavy and should be fairly strong. :)
 
Joined
Feb 7, 2008
Messages
2,652
Location
Nottinghamshire England
Dan

Can you see in the last picture there is a sharp black shadow on the left hand weld where it meets the box ? absent on the right hand weld ?

I would just run the tungsten down that shadow and get a smooth transition between the box and the rather lumpy weld edge ?
 
Joined
May 31, 2013
Messages
2,785
Location
South Benfleet, Essex, England, UK
I have been playing "triangle building" today. What fun it is trying to get everything symmetrical. :ROFLMAO:

It has gone fairly well to be honest, although a veil of polite discretion must be drawn over the first piece of steel that was welded to the central section with the central section round the wrong way completely.
The rectumangrier tube is a bit industrial and heavy-duty for the purpose but the thing wont fall apart easily (I hope).

I cheated and made the first side of the triangle, attached the wheel and was able to see where "correction" was required.
I made the second one with the correction, and then revisited the first and revised it to match. Because I wanted things as straight & true as possible I did grind down some of the welds so that they would lay flat on the table and/or the second side could be clamped to it to be a mirror-image copy.

Here are some pictures of the "fun" that was had.

Checking against the "plan".... Ooops.



Welds are basically OK.


Honest they are!



Having made one side and seen a problem, the second side is made so as to avoid the problem.



By removing any protruding weld material the two sides could be clamped together and the second side could have a correction made on order to avoid the problem found in the first side.



Here I am adjusting the angle of the second side to prevent tyre contact.




Note to self.... corners do not like the lingering heat.



Slit, cut, and shut the offending joint on the first side so as to mirror the perfect second side.




Here they are all nice and even at both ends.




I was pleased to have remedied the initial mistake and get what looks to be two evenly matched sides for the triangle.

Here it is with the wheel mounted in it and it looks OK (I think, at least) ;)
 
Last edited:
Top