Author Topic: Plastic Finger Engine  (Read 9093 times)

Offline rleete

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Plastic Finger Engine
« on: July 17, 2009, 11:32:10 AM »
Well, I finally finished one.  Actually, I did it the weekend of the 4th, but the camera has been busted, so no pics until now.  The camera has been fixed (loose wire), and I'm back in the pic business.

The majority of the engine is P.V.C.  Why? you ask.  Well, it's simple:
  • PVC is free as scraps from work - can't beat the price
  • It is very easy to machine - quick and forgiving
  • It requires no fasteners - glued together
  • No bling possible, so it gets done - sorry, Ralph!

I went down into the shop on the night of the 3rd, and started messing with parts from the many engines I have started.  I realized that the pursuit of polished perfection (Ralph syndrome?) was keeping me from finishing anything.  So, I resolved to make something (anything!), and finish it that weekend.  In order to make it fast, I used the PVC - gluing is faster and easier than drilling and tapping holes.  Also, in order to complete in a short time frame, it had to be fairly simple, hence the finger/treadle design.

The flywheel is 3.75" diameter, and the base plate is 2.5 x 4.0"  All the pins and shafts are brass rod, and pressed in.  I used my rotary table on the mill for the first time to round the end of the finger board and also to cut the round profile of the main bearing gusset.  The only parts I didn't make were the hardware.

After assembly, I discovered that the flywheel didn't have enough mass to keep it going smoothly, so I bolted a brass worm gear (also salvaged from the scrap bin at work) to the face.  It was too heavy, so I cut out the center section, again using the rotary table.  It's hard to see, but it's not quite centered on the flywheel.  Alas, It was Saturday night before the fireworks display, and I was out of time.

So, without further ado, I present the plastic pig:





Fortunately, the flywheel runs straight and true.  Strangely, it seems to run in one direction much better than the other.
Creating scrap, one part at a time

Offline sbwhart

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Re: Plastic Finger Engine
« Reply #1 on: July 17, 2009, 11:54:18 AM »
Way to go that man great job  :clap: :clap: :clap: :clap:

I like the use of plastic and the lack of Bling it makes a very different engine :- what sort of glue did you use ?.

I know its a personal thing but I'm not to keen on bling, sorry Ralph.

Bling free

Stew
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Offline Stilldrillin

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Re: Plastic Finger Engine
« Reply #2 on: July 17, 2009, 12:23:51 PM »
Hey! That`s lovely!  :thumbup:

Beautifully understated.....  :clap:

David D
David.

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Still modifying bits of metal... Occasionally, making an improvement!

Offline Brass_Machine

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Re: Plastic Finger Engine
« Reply #3 on: July 17, 2009, 12:57:28 PM »
That's pretty cool! I didn't expect it to look like that. Nicely done!   :headbang:

Eric
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Offline rleete

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Re: Plastic Finger Engine
« Reply #4 on: July 17, 2009, 01:15:57 PM »
what sort of glue did you use ?

Standard pipe cement.  Solvent based stuff.


Quote
Bling free...Beautifully understated...

It's downright ugly!  Yes, it works, but even the pictures don't show all the messy glue seams and machining marks.  The goal was to get it done in a short timeframe (less than 8 hours), not to make it pretty.  It is rather satisfying to finish one, though.

Thanks for the kind comments.
Creating scrap, one part at a time

Offline usn ret

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Re: Plastic Finger Engine
« Reply #5 on: July 17, 2009, 02:10:02 PM »
 :D FINISHED, IT WORKS!!! NUFF SAID! :beer: I haven't started my 1st engine yet.  Keep up the good work. more :beer:
Cliff
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Re: Plastic Finger Engine
« Reply #6 on: July 17, 2009, 02:11:33 PM »
And now for something completely different, a wonderful finger engine.

It doesn't need bling, and besides, it is rather difficult to do with such material.

I love that PVC, I have made all sorts of small tooling out of it, shame it is rather expensive over here, and my source has dried up, so I have to ration myself in it's use out of what I have left.

If you think yours is ugly, have a look at one of mine.

Bogs


Offline Darren

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Re: Plastic Finger Engine
« Reply #7 on: July 17, 2009, 03:15:39 PM »
Plastic Pig, what an insult.... :ddb:

I think that is wonderful, such ingenuity to think of using PVC..... :clap:
You will find it a distinct help… if you know and look as if you know what you are doing. (IRS training manual)

Offline DavesWimshurst

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Re: Plastic Finger Engine
« Reply #8 on: July 17, 2009, 11:05:58 PM »
Wonderful plastic engine,  it looks much better than much of my PVC constructions.
"Strangely, it seems to run in one direction much better than the other."  A lot of the PVC plumbing in my house runs better in one direction too, downhill! :lol:

Dave

Offline Bernd

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Re: Plastic Finger Engine
« Reply #9 on: July 19, 2009, 07:29:02 PM »
Hey Roger,

Nice job. So is the next wobbler going to be total plastics. Never thought about using plastic to make a "steam like engine".

Bogs,

That looks like a Fred Flinstone design you got there.

Bernd
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Offline Divided he ad

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Re: Plastic Finger Engine
« Reply #10 on: July 19, 2009, 07:54:10 PM »
Nice one Roger  :thumbup:


Contrary to popular belief I do not only like "bling"..... I happen to mostly like shiny stuff   :ddb:


And that ring of brass is crying out for a rag and some brasso!!  :lol:   (Can't you polish plastics too?.....  :doh:   :)  )





Mine prefers one direction as well..... Must be something in the geometry? (Don't drag me through the numbers.... Life's too short!!)


How's about a little vid' Roger?

You don't ask, you don't get I've heard  :thumbup:






Ralph.
I know what I know and need to know more!!!

Offline rleete

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Re: Plastic Finger Engine
« Reply #11 on: July 20, 2009, 08:58:37 AM »
Hey, I hit it with the wire wheel to take the grunge off, that's all ya get!

No video of it yet (HMEM people are clamoring for it, too), but maybe I'll attempt one.  My camera is supposed to be able to take vids, but I don't think I've ever tried it.
Creating scrap, one part at a time

Offline Divided he ad

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Re: Plastic Finger Engine
« Reply #12 on: July 21, 2009, 02:46:35 AM »
Quote
Hey, I hit it with the wire wheel to take the grunge off, that's all ya get!
    :lol:


Thought you might say something similar   :thumbup:



Get that camera figured out too   :poke:    :)





Ralph.
I know what I know and need to know more!!!

Offline NickG

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Re: Plastic Finger Engine
« Reply #13 on: July 21, 2009, 07:29:49 AM »
That's fantastic and I like your theory behind doing it in plastic!

Can't you give plastic a highly polished finish too??!

But what is this, some sort of competition to make the ugliest model?!!!!  :lol:

Well done though, it just shows what can be done .... if you like ugly things!
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