Author Topic: A Wallaby of my own.  (Read 252140 times)

Offline Don1966

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Re: A Wallaby of my own.
« Reply #1050 on: January 27, 2019, 04:26:59 AM »
Damn Dave you sure spit them out in good time. Looking good buddy!



 :cheers:
Don

Online Jo

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Re: A Wallaby of my own.
« Reply #1051 on: January 27, 2019, 12:02:33 PM »
Nice, the Aciera looked like it was enjoying itself as well  :)

Jo
Enjoyment is more important than achievement.

Offline gbritnell

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Re: A Wallaby of my own.
« Reply #1052 on: January 27, 2019, 12:06:35 PM »
Nice work on the rods Dave. Sometimes the simplest looking parts require the most work.
Still following along.
gbritnell
Talent unshared is talent wasted.

Offline steamer

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Re: A Wallaby of my own.
« Reply #1053 on: January 27, 2019, 12:14:41 PM »
Nice work on the rods Dave. Sometimes the simplest looking parts require the most work.
Still following along.
gbritnell

Thanks George, that fixture wasnt too bad to make, but it was worth it...the shell bearings are going to be a challenge.   
"Mister M'Andrew, don't you think steam spoils romance at sea?"
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Offline steamer

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Re: A Wallaby of my own.
« Reply #1054 on: January 27, 2019, 12:16:07 PM »
Nice, the Aciera looked like it was enjoying itself as well  :)

Jo


Happy  happy mill!  Im really impressed with the Sherline RT....its worthy to be mounted on the Aciera.
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline steamer

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Re: A Wallaby of my own.
« Reply #1055 on: January 27, 2019, 12:18:09 PM »
Damn Dave you sure spit them out in good time. Looking good buddy!



 :cheers:
Don

Lol   dont look at the start date!!   :lolb:...ah well    im getting there.  Thanks for looking in buddy.
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline b.lindsey

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Re: A Wallaby of my own.
« Reply #1056 on: January 27, 2019, 01:15:11 PM »
It is a nice little RT I agree Dave. Did you acquire it just for the Aciera or did you have it before?

Bill

Offline steamer

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Re: A Wallaby of my own.
« Reply #1057 on: January 27, 2019, 01:21:30 PM »
It is a nice little RT I agree Dave. Did you acquire it just for the Aciera or did you have it before?

Bill

I bought it from Rob Sussna.   I tweeked what he had to fit my machine.  It's great!

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline gbritnell

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Re: A Wallaby of my own.
« Reply #1058 on: January 27, 2019, 01:56:47 PM »
Hi Dave,
I have made shell bearings three ways. One is to turn the bearing I.D. and O.D. then cut it off. I then make up a mandrel that the bearing will slip onto. The mandrel has 2 diameters, one for the bearing and an enlarged area that I cut a flat on a couple of thousands higher than the bearing surface. Into the flat area I drill and tap a hole. I then make up a small clamp that holds the bearing in place. Using a thin (.005) slitting saw I just cut the bearing in half. This method leaves a small gap between the bearing halves but I have never had any trouble running the engine with the small gap. If you don't want the gap then you do the same procedure only you split the bearing so it's exactly 1/2 diameter. You then discard the small half. You have to make twice as many bearings because of the discard but it doesn't use up much material. I have also taken 2 pieces of rectangular stock and tinned and soft soldered them together, leaving on longer than the other so I can use the split surface for setup in the four jaw chuck. You drill and bore the I.D. first then the O.D. You then cut the bearing free from the stock. Now you heat it and unsolder the two halves. In practice it still leaves you a minute gap where the solder was. To keep the bearing from turning in the rod or main bearing I drill and press in a small brass pin then drill one half of the insert. This keeps the bearing from rotating.
gbritnell
Talent unshared is talent wasted.

Offline steamer

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Re: A Wallaby of my own.
« Reply #1059 on: January 27, 2019, 02:11:54 PM »
Hey George,

I did your"make two pieces cut twice as many bushes as you need" approach for the main bearings, with a tubular pin to allow for oil feed.  That worked really well.

I think I'll do the same for the big ends.    I think what I'm going to do is turn up the OD features on some short pieces of stock, and then cut to dead center.  I'll then cut two free, and make a clamp to hold them together and then bore them to size....at least that's what I'm thinking of right now.   I might even use a rod as the clamping fixture to hold the two halves together for boring....I'm still noodling it a bit.   The shell is pretty thin at about 0.031, which is why Im thinking of splitting it first, and then boring.   

The little ends are just bronze bushes and are obviously simple.

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline steamer

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Re: A Wallaby of my own.
« Reply #1060 on: January 27, 2019, 11:33:30 PM »
Making some progress on the con rod big end bearings.    I made 4 solid bushes.   I'll be cutting them into 4 half shells

Then I'll be boring the plate to accept the half shells as a pair.  From there, I'll face to width and then gently bore to size.


The reason I'm doing this is that the bores are 0.4375 and the con rod bores are 0.500.  So the shells are only 0.031 thick.

Now...do I do it in the mill? or the lathe?....hmmmmmmm

Dave
   
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Art K

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Re: A Wallaby of my own.
« Reply #1061 on: January 28, 2019, 02:38:39 AM »
Dave,
Those rods came out real good.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline 10KPete

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Re: A Wallaby of my own.
« Reply #1062 on: January 28, 2019, 04:12:45 AM »
Those are great looking rods, Dave! I'll be watching the process for thin-walled bearing shells carefully.

 :ThumbsUp:
 :popcorn: :popcorn:

Pete
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SB 10K lathe, Benchmaster mill. And stuff.

Offline b.lindsey

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Re: A Wallaby of my own.
« Reply #1063 on: January 28, 2019, 02:22:20 PM »
Dave, do you have a collet which would fit the major OD (flanged part) of the bearings? I would probably do it on the lathe but a 5C collet fixture on the mill would work too.

Bill

Offline steamer

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Re: A Wallaby of my own.
« Reply #1064 on: January 28, 2019, 02:28:56 PM »
Actually the fixture will be bored to the shell OD.   Its essentiall a bearing cap assembly.   But I suppose i could do it on the Logan with 5c

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

 

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