Bicycle Dynamo powered by model I.C. engine

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I have been reading this thread with interest. Amongst several projects I have on the go at the moment is one of the 1/4 scale hopper cooled horizontal open crank Red Wing engines.

I year or two ago I rescued a dynamo from the front wheel hub of an old bike thrown in the big skip at work, with the intention of driving it with the Red Wing engine, when I finally finish it.

This dynamo is also a Sturmey Archer and although in good external condition it is in need of a strip and rebuild. I think it dates from the late 1950's or early 60's, it's stamped on it somewhere. A special keep plate is required when dismantling to prevent loss of magnetism.

When I was a teenager I had a speedometer on my bike and this, like your dynamo, was also driven off the front tyre. So while eagerly seeing how fast I was going it was actually slowing me down. I remember crashing into the front of a parked car while concentrating on the speedo as I frantically tried to break the 15 MPH barrier! Spectacularly bent front forks were the result.

I also remember fitting a small mileometer, this was mounted on the front wheel spindle and was driven off a small lug clamped to one of the spokes. I am sure I also crashed into another stationary solid object while squinting to make out the vast distance I was sure I had travelled, bloody hell!

Anyway, this thread has renewed my interest so I will take a closer look at that old dynamo. I suspect the hub type do not need to rotate as fast as the tyre driven type.


LMAO...,

Those are indeed memories that will always return and make one laugh.

I flipped when you mentioned the "mileometer" it was one of those "status" things at school, it was a prized possession back then in Holland when I was a kid.
A nice solid and compact chrome little thing with the tiny window on top. it read off miles (kilometers in my case.)
A wonderful little ticker that went all the way to 9000 klicks.
Totally useless mind you, but fun. J.
 
I bought a lot of five bicycle dynamo from Ebay. I have four to give away as Christmas Presents. Any taker??. DHL from Singapore will be expensive.

Gus...,

If you can give a price and possible shipping I am interested.

I believe that mailing it here might be cheaper, or better than DHL.

Thanks, J.
 
Brian,

I follow your neat little projects with interest as they are just right up my alley.

This dynamo thingy has got me thinking on (again) making another wind powered bulb lighter lol.

I don't know where you get the energy and time to do these little things, but I sure get persuaded to have a go myself.

I think your engine is a gem, and should possibly come close to one Horsepower.

I'm having a blast just reading, thanks for posting these interesting projects,
Regards J.
 
I am always pleased when whatever I build looks like the 3D model. The only change I made is that I didn't but the large radius on the bracket holding the dynamo, because I may need it to have a flat top for mounting the bulb. I haven't totally worked that out yet, but I will tomorrow. So far--So good!!!

 
jj-smith--I'm glad you enjoy my posts. It's amazing what old men do to keep from going crazy!!! The engine wouldn't have anything remotely close to 1 HP. The piston is only 1" diameter. The Briggs and Stratton washing machine engines I used to mess with when I was a kid had a 2" piston and only put out about 5/8 Horsepower.---Brian
 
Gus...,

If you can give a price and possible shipping I am interested.

I believe that mailing it here might be cheaper, or better than DHL.

Thanks, J.

Will be passing by GPO aka General Post Office nearby to get a quote.

Hang on. There.
 
jj-smith--I'm glad you enjoy my posts. It's amazing what old men do to keep from going crazy!!! The engine wouldn't have anything remotely close to 1 HP. The piston is only 1" diameter. The Briggs and Stratton washing machine engines I used to mess with when I was a kid had a 2" piston and only put out about 5/8 Horsepower.---Brian

You made me think Brian,

You're right of course, I have a few stationary engines, and the International 2-1/2 - 3-1/2 has a piston way bigger than the one you made, I surprise myself again.., I was thinking on the little mopeds we had in Holland and they only put out 3 hp I think the pistons on those were fair size too though, they could be souped up to go faster but still only 50 or 60 km/hr. Just got it mixed up.

I really like the stand you made for that dynamo, it looks fantastically like it belongs! Well done.

Regards, J.
 
Of course there is more to this than just mounting the dynamo itself. The squeeze bolt is going to morph into a handle, and I have added a bulb, bulb socket, and bulb socket support. The only remaining unknown is the release handle for the sprag.
 
The bulb holder is just a bit tricky. It has to contact the outer shell of the bulb, but not the center contact. Since I don't have any Corian, I will fall back on the "hillbilly" insulator and turn one from a piece of hardwood. The insulator will epoxy into the end opposite to the bulb and have a 3/32" hole through the center for the contactor wire which gets the electricity from the dynamo up to the end of the bulb.

 
The engine has a throttle on it so I can run it at a reasonably low rpm. The bulb I have is out of a flashlight with two D cells in it, so is basically a 3 volt bulb. The dynamo probably puts out 6 volts at peak rpm. Now in a perfect world, I would be able to get a 6 volt bulb with the same diameter base as the 3 volt bulb, but the world is seldom perfect. There is a blizzard going on outside at the moment, but I think perhaps I will mush my Huskies down to Ideal Supply and see what sizes (if any) their 6 volt bulbs are before I go any farther.---Brian
 
Well I'll be----Sometimes ya just get lucky. The hardware store had 6 volt bulbs with the same sized base as the 3 volt flashlight bulb I based my bulb holder on. I must have done something right in a previous life----I have absolutely no idea why the package says 6 volt lanterns at the top of the package and 4.8 volts at the bottom of the package.
 
So---If I just had a handle to disengage the sprag when I want to loosen the belt, I think I would almost be done. I have spent the day playing and have grandchildren coming to visit overnight, so I won't get back to this today. I also got a "good news" phone call from a customer who wants me to design a packaging machine for one of his products, so I will be gainfully employed for a week or so.
 
I have absolutely no idea why the package says 6 volt lanterns at the top of the package and 4.8 volts at the bottom of the package.
At some point people wanted brighter torches(flashlights ;) ) so the torch manufacturers started using lower voltage rated globes. They run hotter and brighter but the obvious tradeoff is reduced lifetime of the globe. 'Dolphin' brand torches usually have a spare globe inside for this reason. I always forget to replace the spare :rolleyes:

Edit:
Just made a liar of myself.... opened up my Dolphin and.... the spare is there! Hahaha

IMG_20141129_141351.jpg
 
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Yes!!! We have a sprag release handle. Nothing too scientific here--just something to disengage the sprag from the rack so I can loosen the belt off when I want to.
 
How about 70 pounds lighter and 30 years younger----

I'm with you on that one Brian lol, don't look for a minute and prrrt, you've gone fat!

I'm still at Jack Benny's age though! (in my mind!):rolleyes:

Cheers, J.
 
Tape is a good idea but how about a lobster rubber band around the pulley. You know the ones that keep the lobster claws closed? Small-ish diameter / wide and really strong and lots of friction.
Too big??

Sage
 

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