PM Dynamo Kit

[IronHorse]

I bought a Dynamo kit this summer at the Cookstown Steam Show. It was a fairly basic build without much drama ( did not break any tools or castings).

I posted this picture a while ago in responce to a fellow modeler on holding the casting on the mill. Looks a bit complicated, but I could not get it to fit right in my small vice.

Next is to bore the cylinder out. I picked up this boring bar at BusyBee and ground my own cutter. What an improvement over the cheap carbide tipped ones I had used before. I have a sacrificial piece of aluminum so I don't hit the chuck.

A little bit off the sides.

Drilling the end plates. I found it hard to locate the center of a cast boss. They are not perfectly round and the sides taper, so I did it by eye.

Here I am drilling the holes for the end plates. I prefer to drill thru both pieces to make sure they align at assembly time.

I made a form tool for this operation and it made it easy to make this small part.

I roughed the basic shape on the grinder then I use some cheap ($4 this set) diamond bits to grind down the final shape.

Here is another form tool I made. One day I will have to make a ball turner attachment!

Testing the fit of all the parts. I replaced the screws with some nice stainless bolts.

All the parts waiting for assembly. I like to leave the painted parts on the heating/airconditioning vent for a week before I do the final assembly. Just to make sure the paint is really hard. I used one of those vibrating engraving tools to "erase" the parting line on the main body.

The end plates with the pre-made brushs installed.

And another view showing the binding posts.

This coming weekend I will do the final assembly and post some more pics and video.


IronHorse

 

[zeeprogrammer]

I'd like to build a dynamo myself sometime.
Looking forward to your pics and vids!

 

[Kermit]

Hey Ironhorse. I love a good dynamo build. Never get tired of them.

One suggestion on your screwed down sheet brass connections and areas immediately surrounding them. Apply a coat of some clear nail polish(thin it with acetone if too thick) after you have made that connection. The look of the model is preserved by using a clear, but a dark red sometimes looks real good. They have coatings that are a little better than nail polish of course, but not for two bucks!! ;D

I've used the nail polish trick for some decades now, in alot of my electronics bench work as well as model building. Now that I've started messing with metal, I can see it will come in handy in this arena also.

Good close ups too, 8)
Kermit

 

[joe d]

Ironhorse

This is coming along really nicely. You have reinforced my desire to build this kit!

Joe

 

[Deanofid]

I'm liking it too, and thinking I want one. It looks like a pretty nice kit.
Didn't know it was CI.
Good work, IronHorse.

 

[gbritnell]

Nice work Ironhorse. Actually for doing small radiused parts like the lifting eye your way is better. I have a ball turning attachment for my lathe and it works fine except you can't get into a tight corner on the chuck side of the part. The only thing that's important when using a forming tool is to watch the speed as there is so much surface area that you can develop a chatter quite easily.
gbritnell

 

[steamer]

Nice Work IronHorse!

Been looking for a good job for my "Not so little Workhorse"


Think I found it! ;D

Dave

 

[NickG]

Nice Iron horse,

I like that, it's really good and would give our engines something useful to do whilst still looking the part.

NIck

 

[IronHorse]

Well as promised; final pictures and video of the Dynamo.



Pulley end view

Communicator end view

End View

Here is a video of the Dynamo running in "Motor" mode. I have not tried to run it of any of my engines yet, I am sure the PM2A or my big Jensen would run it. I am also sure none of my hot-air engines would run it.


Maybe I will build a large "Mill Engine" to power it in the future. Any suggestions on a engine that would look "scale" to this Dynamo?

IronHorse

 

[ChooChooMike]

Wow ! That came out pretty dern nice !! :bow:

 

[zeeprogrammer]

Okay...I've added that to my list of projects.
Thank you so much. ;D

You mentioned a couple of forming tools you made. Could you describe a little how you made them? I'm especially interested in the one that looks like a half-circle? How did you make it so 'perfect'?

Also, you mentioned a vibrating engraving tool. Got a pic? How did you use it to 'erase' the parting line?

I was real happy to see this thread.

Thanks.

 

[IronHorse]

Zee

I just roughed out the basic shape with the big grinding wheel and then put one of those diamond bit tools (shown earlier) in a dremmel and grinded the final shape.

For the casting seam, I filed down the ridge so it was level and used the tool shown to "Peek" little indentations to match the surrounding texture. These tools are used to engrave ID onto metal objects. This one is real old, I found it in my dads old toolbox. It vibrates like crazy and sounds like a mad bumble-bee ;D

IronHorse

 

[zeeprogrammer]

Ah. Thanks IronHorse.
Funny...I just bought an engraving tool today. Impulse item. Wonder if it works on wrinkles.

Thanks.