Author Topic: Elmer's Grasshopper  (Read 6086 times)

Offline RReid

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Re: Elmer's Grasshopper
« Reply #30 on: May 09, 2021, 12:53:58 AM »
Hi Joe. Thank you for the encouraging words.

Today I started by making an oil cup for the other crankshaft journal to match the one made yesterday.


Then I moved on to the “valve crank”.


After I reduced the bar I started with to size and drilled the two holes, I tried something different to round over one end. In an order for some odd and ends, Taig mistakenly sent me their radius turning tool rather than one of the things I actually ordered. OK, similar value, so rather than make a fuss I kept it and ordered the bit I really wanted later. I clamped the radius tool in the little mill vise and a small diameter Dremel sanding drum in the spindle. With a pin through the part into the swivel of the tool, it was simple to swing the stock against the sanding drum, advancing the table a bit each time. It did help that the stock wasn't cut to final length, so it was easy to hold. And less frightening than an end mill.


Next, I mounted a piece of Al in the 4 jaw, drilled and tapped the center 3-48, then moved the chuck over to the mill to drill a 1/16” hole 7/16” away from center. Back on the lathe, the now cut to length part was screwed and pinned to those two holes.


This allowed me to thin it down to 1/16” for most of the length while leaving a 3/16” boss at the end with the larger hole. I used a brass pin (happened to be brass tubing), so it just got turned down as I went. You can't see it, but it actually is still there in the photo.



Regards,
Ron

Online Kim

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Re: Elmer's Grasshopper
« Reply #31 on: May 09, 2021, 05:36:19 AM »
Nice series of ops for the valve crank.  One more part down!   :popcorn:
Kim

Offline RReid

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Re: Elmer's Grasshopper
« Reply #32 on: May 10, 2021, 08:52:47 PM »
Thanks Kim. Yep, one part at a time.

Here's one way to kluge a follow rest:
Regards,
Ron

Offline RReid

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Re: Elmer's Grasshopper
« Reply #33 on: May 15, 2021, 01:06:10 AM »
Shop time has been a bit disrupted this week by roofers doing their thing and causing a rain of dust and bits of OSB sheathing in the garage. Been chunking away on valve gear parts when it's not too bad though. The steam chest just needs to be drilled for the mounting studs, and the valve rod still needs a bit of work at the outer end to mate up with the fork shown next to it. Guess I should make the valve next.
Regards,
Ron

Offline EricB

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Re: Elmer's Grasshopper
« Reply #34 on: May 15, 2021, 02:29:55 AM »
Looking good! Clever use of the radius tool too. I wonder if that tool will fit my Sherline.  :thinking:

Eric
« Last Edit: May 20, 2021, 08:42:08 PM by EricB »

Offline RReid

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Re: Elmer's Grasshopper
« Reply #35 on: May 15, 2021, 03:16:09 AM »
Thank you Eric. As for the radius turner, I don't know, but if it doesn't fit the Sherline as is I'm sure it could be adapted, we being machinists after all!  I was using it upside down, with the tool holder clamped in the mill vice. Here's a catalog picture. In general, as much as I really like the Taig machines, their accessories aren't as nice as those offered by Sherline in my opinion, of which I have a couple.
Regards,
Ron

Offline EricB

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Re: Elmer's Grasshopper
« Reply #36 on: May 15, 2021, 05:21:27 AM »
Sherline's radius tool cost 5 times as much, is much more complex, takes two hands to operate, and puts you dangerously close to the chuck. I can't justify Sherline's cost but I want a radius tool of some type.

I've been thinking of getting a Taig ER-16 adapter so I might get their radius tool too.

I also see in your kluge follower rest photo that you have a Sherline motor on your lathe. The spacer blocks for the mounting screws look much better than the washers they come with. I'm going to have to make that mod too.

Eric

Offline RReid

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Re: Elmer's Grasshopper
« Reply #37 on: May 15, 2021, 02:58:16 PM »
Quote
Sherline's radius tool cost 5 times as much, ...

Yes, that is the trade-off, isn't it. Just know that as designed that tool will do a good 180 degree radius, but not much more than that. It is not a full on ball turner.

I do like the ER-16 adapter and use that all the time. Adding the Sherline motor was a bit spendy, but a nice upgrade from a single speed AC motor and well worth it to me.
Regards,
Ron

Offline RReid

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Re: Elmer's Grasshopper
« Reply #38 on: May 20, 2021, 08:37:40 PM »
The Grasshopper is almost complete. I want to paint the steel base, but before taking it apart I wanted to make sure it runs OK. I think I'll leave all the other parts “natural”.

Here's a few photos and a short video. I need to make up a throttle valve for the air line, the trigger on my air nozzle is too sensitive, even at only 10psi. I'm holding it just barely cracked.






<a href="https://www.youtube.com/watch?v=B8qBQvoKT6Q" target="_blank">http://www.youtube.com/watch?v=B8qBQvoKT6Q</a>
Regards,
Ron

Offline EricB

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Re: Elmer's Grasshopper
« Reply #39 on: May 20, 2021, 08:44:46 PM »
 That's a good looking engine!  :ThumbsUp:

You should throw a size reference in the pictures so we can see how tiny it is.

Eric
« Last Edit: May 20, 2021, 08:48:45 PM by EricB »

Online Kim

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Re: Elmer's Grasshopper
« Reply #40 on: May 20, 2021, 11:09:34 PM »
Congratulations on a runner!  That's always fun to see it working for the first time!  :ThumbsUp: ;D

Now you can go a d paint it knowing that it works!
Kim

Offline RReid

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Re: Elmer's Grasshopper
« Reply #41 on: May 20, 2021, 11:18:43 PM »
Thanks Eric! Thanks Kim!

Quote
You should throw a size reference in the pictures so we can see how tiny it is.
I can do that. It's not all that tiny, especially compared to Elmer's "Tiny", the one on a wood base.


Regards,
Ron

Offline Flyboy Jim

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Re: Elmer's Grasshopper
« Reply #42 on: May 21, 2021, 03:19:21 AM »
Congratulations on a fine looking and running engine.  :ThumbsUp:

Jim
Sherline 4400 Lathe
Sherline 5400 Mill
"You can do small things on big machines, but you can do small things on small machines".

Offline joe d

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Re: Elmer's Grasshopper
« Reply #43 on: May 21, 2021, 12:09:33 PM »
Congrats Ron!  Good looking, and a runner too :ThumbsUp: :ThumbsUp:

Cheers, Joe

Offline MJM460

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Re: Elmer's Grasshopper
« Reply #44 on: May 21, 2021, 01:16:23 PM »
Well done Ron.  Always very satisfying to see your creation run.  And it’s an interesting looking engine too.

MJM460

The more I learn, the more I find that I still have to learn!

 

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