[modeleng] Re: Photobucket

Hi Al and listers,

I had put in a proper email header for the email to the list, but 
Photobucket deleted it somehow. Anyway I'm glad you liked the photos. Thanks 
for your kind comments. The parts are for a 1.5" scale Bill Harris 
steamroller I'm making.

A quick recap of the steps to get the cylinders to this point and the 
reasoning:

1. started with a 2x2" continuous cast iron bar. Nice homogenous material 
and inexpensive. I paid about $10 for a one foot piece of 2x2. It machines 
beautifully as you can see.(I did price Stuart castings but they would have 
been several hundred dollars, and I just can't afford that especially if 
there's a blowhole or I screw up.)

2. I faced one side of the block and bored both cylinders at the same setup 
so I know that the bores are square to the face. I marked this face next to 
each bore with an extra centredrill dimple, 1 for no.1 and 2 for no.2 so I 
know these are the master datum faces for future machining. The bores were 
drilled 11/16, bored to .745, then reamed to .750" and a nice finish.

3. drilled and tapped 3-48 for cyl cover screws while on same DRO setup as 
the boring, so the holes will be on location within a thou or so.

4. flipped the block over and faced the opposite side parallel to the first 
and at the right height. Since both cyls were milled at the same setting I 
know they are the same length. Also drilled and tapped this side's cyl cover 
holes.

4. separated the two cyls by sawing.

5. setup and machined the port face on each cylinder, and drilled and tapped 
steamchest mounting holes 3-48.

6. set up each cyl at 30 degrees with a setting gauge and milled a small 
counterbore at the bore to end face junction. This gives a flat face for a 
centredrill and the port drill to start on. Then it's a simple matter to 
drill to the port face opening. To make sure I didn't drill too deep and cut 
past the inlet port and thru to the exhausr port, I used a 'dancer'. These 
can take many forms but in this case I just cut a piece of shim stock wide 
enough to fit the milled port opening in the port face, and held it with a 
wood clothespin. When drilling downward, when the drill broke through and 
touched the shim stock the shim and clothespin started dancing around, I 
knew I was deep enough. Old trick but works good.

7. set up again and drilled, tapped 1/4"-40 and counterbored 3/8" dia for 
exhaust port.

8. set up again and drilled and tapped 5-40 for cylinder drain cocks. the 
drain holes thru to the bore were drilled 1/16".

I purposely left the blocks a cube shape to simplify holding and setups 
until all holes and working faces were machined. If I were starting with a 
Stuart casting this would be a lot more difficult to set up and hold.

Next step is to machine the outer shape to the Stuart semi round shape at 
one side tapering each side to the port face.

Hope this gives an idea of what I did and why.

Best regards, Jeff Dayman

>From: Allen Messer <al_messer@xxxxxxxxx>
>Reply-To: modeleng@xxxxxxxxxxxxx
>To: modeleng@xxxxxxxxxxxxx
>Subject: [modeleng] Re: Photobucket - Jeff Dayman wanted you to check out 
>this album
>Date: Sun, 17 Feb 2008 14:12:34 -0800 (PST)
>
>Jeff, Thanks for sharing the photos of building the
>traction engine's cylinders with us.  Looks to me as
>if you have done an outstanding job on it!
>
>Al
>--- jeffdayman@xxxxxxxxxxx wrote:
>
> > I created this album on Photobucket and wanted to
> > share it with you.
> > Check it out here!
> >
>http://s169.photobucket.com/albums/u214/roller-guy/roller-cyl-mach/?albumview=slideshow
> > To upload, link, publish, and share image and video
> > files, use Photobucket!
> >
> > ____________________________________________
> > Photobucket.com - http://photobucket.com
> > Join the biggest image and video sharing service in
> > the world.
> >
> > MODEL ENGINEERING DISCUSSION LIST.
> >
> > To UNSUBSCRIBE from this list, send a blank email
> > to,
> > modeleng-request@xxxxxxxxxxxxx with the word
> > "unsubscribe" in the subject line.
> >
>
>
>
>       
>____________________________________________________________________________________
>Be a better friend, newshound, and
>know-it-all with Yahoo! Mobile.  Try it now.  
>http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
>
>MODEL ENGINEERING DISCUSSION LIST.
>
>To UNSUBSCRIBE from this list, send a blank email to,
>modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject 
>line.


MODEL ENGINEERING DISCUSSION LIST.

To UNSUBSCRIBE from this list, send a blank email to, 
modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.

Other related posts: