Nothing to lose really.

You sometimes see bolty things on horizontal slots to stop that happening ?
If the slots were long enough could they also be used to take up the slack between the SA8 speed and the 2WD unit ?

Paul
 
In a departure from our advertised program today saw the universe flipped by 90-degrees.

Well, OK just a Sturmey Archer 8-Speed flipped by 90 Degrees. :)
I found that if I turned the proposed dropout tabs to face the rear of the trike then the 8-Spd could sit inside the rear triangle.

IMG-20230803-134429-528.jpg


It does create an issue in that the power-side of the chain will want to saw its way through the cross-rails of the seat (unless either the seat is raised, or a diverter pulley is employed).

thinking ?
do we really need a triple on the front ? looks as though with the 2 smaller rings there would be no seat interference ?
also could the BB go below the frame ?

paul
 
thinking ?
do we really need a triple on the front ? looks as though with the 2 smaller rings there would be no seat interference ?
also could the BB go below the frame ?
No triple really required it is just conveniently on a bolt-up mount for testing purposes. BB could go below the frame but then any option for having a double/triple up front is taken away completely.
It may be that I chain it up for testing with it under the frame and only on one chainring(no front-mech) to see how it all works and then alter it later.
The dropouts are now fully welded on where you see them here. I need to get a seat mount (with backrest stays) sorted so that I can determine the BB position and the front forks.
This is a long journey it seems. :)
 
Another little diversion....
I bought some acetal/Delrin slugs on evil-bay and I am trying to make a diverter pulley (or two).
Now, I admit I have got my order of operations all wrong and have boxed myself in a bit, but I think I will be able to recover.

Here is what it looks like so far. Gosh the Delrin swarf/flakes go everywhere. It is nice to work with though. :)
This will go on the drive side of the chain and will have dual-bearings and a 12mm axle.

Aluminium side-plates may be required.

IMG-20231003-153008-271.jpg
 
If making ones from scratch wouldn't it be better to design the sides in rather than bolt on something extra?
Yes indeed. The available/affordable delrin blanks I got are only 60mm diameter so a little on the small side (76-100mm would be better).
I am hoping to provide a wide-enough valley for a chain to run on and to accommodate any lateral movement (e.g. a dual/triple chainring up front).
The walls of the pulley are mainly there to encourage the chain to keep clear of the side-plates which will be the ultimate/final defence. :)
 
This was the first ever attempt to make a pulley, so I am not too disappointed, I made many errors, but it will work.

Here's the MK1.
IMG-20231004-205228-575.jpg
 
Dan

Excellent do you need 1 or 2 ?

I am in favour of bolt on side plates , can be replaced should they get damaged or worn etc.

If you don't believe they may get damaged ask DannyC about the ' seat incidence ' !

Paul
 
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Paul,

It probably only needs the one, but I may make another one to eradicate all the mistakes I made the first time and to perfect the technique.
I possibly have enough delrin for 5 or 6 pulleys.
 
Danny, is the bore a through hole or is it shouldered in the middle?
(Guess you have a middle spacer in there)
There are many ways to machine them.
With an end shoulder for one bearing, middle shoulder for 2 bearings.
You may need an undercut for a circlip to prevent the pulley walking off the bearings.

I've made 5 pulleys so far this year. Three different designs. Bought a 75mm dia black nylon bar 1 metre long, should keep me busy.
If making in 2's you can machine one gripping one end, turn round to machine other one. Then part off, with a long blade.
Use tailstock support.
Second load, bore operation for the other bearing.
Or if making singles cut the blank with a 10mm(ish) grip length.
Machine off excess.
Hope that helps.
I will making some with the centre sprocketed teeth next, such fun.

Martin.
 
I got an already made pulley and merely turned that so it was flat on the bottom. It seemed easier than reinventing the wheel.
 
I got an already made pulley and merely turned that so it was flat on the bottom. It seemed easier than reinventing the wheel.
Popshot

Was this for drive side or return side ?

If drive side has it lasted ?

If so where did it come from ?

Paul
 
I made another one today (just for S&G's) and I have the option to make it a veritable chain-trap with thicker sides and narrower groove/valley of 8 - 9mm.
I think this might be a good compromise.
 
Danny, is the bore a through hole or is it shouldered in the middle?
(Guess you have a middle spacer in there)
There are many ways to machine them.
With an end shoulder for one bearing, middle shoulder for 2 bearings.
You may need an undercut for a circlip to prevent the pulley walking off the bearings.

I've made 5 pulleys so far this year. Three different designs. Bought a 75mm dia black nylon bar 1 metre long, should keep me busy.
If making in 2's you can machine one gripping one end, turn round to machine other one. Then part off, with a long blade.
Use tailstock support.
Second load, bore operation for the other bearing.
Or if making singles cut the blank with a 10mm(ish) grip length.
Machine off excess.
Hope that helps.
I will making some with the centre sprocketed teeth next, such fun.

Martin.
Hi Martin,
I am sure Nylon is fine but I had heard that over time is absorbs moisture and swells a bit, so I went with Delrin which doesn't.
I have made them so that there are 2 pockets (one on either side of the pulley) to hold the bearings in.
An 8..10mm central section is to act as a separator between the bearings. I guess this is your "middle-shoulder" option.
As there is a "nut" on either side of the pulley it cannot "walk" anywhere (inwards or outwards) I think/hope. :)
 
And here is another one, it came out a bit better, may not need any side-plates.
I tried it with a length of chain for "fit" and it seems good.
image.png
 
Popshot

Was this for drive side or return side ?

If drive side has it lasted ?

If so where did it come from ?

Paul

Both and yes no issues. The drive side was / is a very mild deflection of the chain path though and that is likely the biggest factor in any wear rate. Got them from ebay. They were U shaped for a rope initially and I spun them in a drill in a vice and used a wood chisel to turn them flat. This was before I got the lathe.
 
And here is another one, it came out a bit better, may not need any side-plates.
I tried it with a length of chain for "fit" and it seems good.
image.png

That looks like it could survive any worst case scenario yet is probably not overly heavy. Looks great.
 
That looks like it could survive any worst case scenario yet is probably not overly heavy. Looks great.
Thanks, it is 60mm Dia by about 25mm overall width, with a 9mm channel in the middle and the bearings are standard 28x12x8 so it should be able to survive a bit of punishment. 🙃
 
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