Another FWD Delta trike.

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Not sure why you need to do this ?

You already show pictures of the rear frame where you can sit on it ?
So why not just build simple wooden frame that can support the front end in the desired position ?



This one is useful as it can hold up a pivoting front end should you nee to work on it ?

or
Even simpler




Saves having to measure and draw most of an already existing frame ?

Paul
The problem is a lack of timber Paul. All the timber I had amassed for such things has been stolen used by my children on their DIY projects. :(
 
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And so by popular request...
I cobbled together some paint-cans, a set of wheel chocks and an axle-stand and I managed to get the various things to stay still long enough to take a picture of it in a simulated "together" formation.
The BB shell axle is 68cm from the seat mount (as per the other Python). The BB-shell is "just" the other side of the wheel's axle.
I could not move the wheel closer to the seat as the main-keel was touching the tyre; but if I chop some of that off the wheel can come closer and the BB further forwards around the wheel to a more 1:30 PM position.
You can see that the front frame members I have made will be able to be secured under the main keel on a Pivot that will be mounted to a downward & forward pointing spar welded on the underside of the main keel.
A fold-down set of 3 "mounting steps" will be required in order to get on the seat....Of Course! ;)
As you can probably see, the seat height is at or just below the 24" wheel height.
That's all for now, I'm a bit tired today for some reason. :(

 
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Just a thought but given the BB is now largely above the axle it will move more left and right as a function of wheel tip compared to how much it'd move if out front on a 20" wheel. Your hips and legs will have to articulate more to cope.
 
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Just a thought but given the BB is now largely above the axle it will move more left and right as a function of wheel tip compared to how much it'd move if out front on a 20" wheel. Your hips and legs will have to articulate more to cope.
That's a good call Popshot, It may be an unrideable setup for me (like all my other trikes it seems). :(
 
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So it was with my heart in my mouth that I ruined a perfectly good rear suspension frame by cutting off its dropouts.
Welding the stubs that were left to my home made "frame" was an exercise in frustration and anglo-saxon invective.
But I think we got there for this first part (I can mount a wheel in it and it appears to sit "reasonably-true" to all the other bits.
Here is a video to prove it.







 
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Very brave that man ....



You need a medal ?

Several here would fit the bill ?

Paul
 
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Very brave that man ....



You need a medal ?

Several here would fit the bill ?

Paul
Gee thanks. I'd like to thank... My Mum & Dad, my welder, my grinder, my flap discs.
 
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In an absolute travesty of the metalworkers art I put the first of the two strengthening braces on the front frame.
The tube is 12mm square @ 1.5mm so should be plenty strong enough for the task.
I managed to blow a big hole in the wall of the tube, that I then had to fill in.

I may attempt to put the other side's brace in tomorrow.





 
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Gee thanks. I'd like to thank... My Mum & Dad, my welder, my grinder, my flap discs.
Sheesh ..



It's a medal not an Oscar..

Paul
 
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Today I put the other brace on the front triangle.


When rotated around to put the pivot end higher and the BB further forward and a bit lower it looks like this.


That yardstick is there for me to see where my required 68cm from BB to seat mount cup will be.
Yup, smack in the ball park (better than smack in the balls too! ) :)
 
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Dan

that's a crazy angle , will it be at that angle when attached to the rear end ?

nice to see a usable wheel in it.

Paul
 
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Dan

that's a crazy angle , will it be at that angle when attached to the rear end ?

nice to see a usable wheel in it.

Paul
Hi Paul,

I hope it won't be because that is indeed a bit crazy, I was just rotating it to see where the BB went (around the clock-face) and the end was a convenient place to stick the ruler against.
On the plus side is the fact that it is an extremely sturdy frame & triangle and there will be no chain-line issues as far as I can see. :)
 
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of course if you squeezed a horizontal pivot in brushing the tyre and connected the spring to the Python pivot you could have front suspension ........

I'll get my coat , shall I put the milk bottles out when I go ?

Paul
 
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of course if you squeezed a horizontal pivot in brushing the tyre and connected the spring to the Python pivot you could have front suspension ........

I'll get my coat , shall I put the milk bottles out when I go ?

Paul
TBH, I think I have enough to contend with already. ;)
 
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Yesterday and today in my "free" time I made this carrier for a Python-pivot.
It is all 4mm plate steel, reinforced at each end with buttresses.

The pivot itself is 3.5mm walled tube with 2 Tapered Roller bearings and a separator tube inside.
The current "axle" is just bit of M12 all-thread to hold all the bits together for welding.
Yes, it is OTT and definitely a little heavy, but I know it will not break; and with old bones getting more brittle by the day, that is my main criteria.
I should be able to weld whatever I want to the pivot outer sleeve.




 
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Dan

You will get more than brittle bones if that rolls off the bench onto your foot !

Paul
 
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Dan

You will get more than brittle bones if that rolls off the bench onto your foot !

Paul
You may be right. ;)

I am hoping it will be usable, if not, I can make another pivot to go in the carrier.
 
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The picture below is my little mockery mock-up of what it might look like when the major bits are stuck together with hot-metal glue and some nuts and bolts.


I can clearly afford to lose some inches round my waist here in the rearmost edge of the front frame. There's a good couple or three inches I can trim off here.
Everything was made over-length on purpose and the existing frame cross-piece here was placed there to keep the frame side-rails aligned and parallel while the frame strengthening was carried out.

One other major concern is where on earth to put the handlebars (and how?). That is a L-O-N-G way from the root of the front frame up to the riders hands.
It may not indeed be possible. Time will tell.

One obvious option is to mess with the rear swing-arm and remove the bend in it and make it flat. That would drop the main keel lower and towards the level of the front-frames attachment area.

Lots to think about.

 
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