GDB Inline 4 Cylinder OHV I.C.

[Vixen]

Hello Bob

It's nice to see more, well executed, 'old school' milling. 

Mike

[Roger B]

Still following and enjoying     

[90LX_Notch]

Thank you Mike and Roger for your continued support.  I apologize for taking so long to reply.  Work has been crazy in preparation for the Summer Season.

-Bob


Oil Pan continued-

The outside sidewall was milled with a 5 degree tapered endmill.  (By luck the endmill was in a toolbox purchase that I had made years ago.)

Next a .125 radius cutter was used along the bottom edge of the Oil Pan.

The Pan was then clamped to an angle plate and a .660 gage block stack was inserted into the clearance pocket for the Rear Main Bearing Cap.  An edge finder was used to pickup the blocks in order to determine the centerline of the pocket. 

Next a .375 endmill, followed by a .500 endmill, was used to rough out the required .275 radius for the Rear Main Bearing Cap.

-Bob

[gldavison]

Hi Bob,
 I like the way you figure out how to set things up. Makes me think you were a professional machinist in another life. 

 Excellent job on the documentation  and the machining.  Keep it coming.

Gary

[90LX_Notch]

Gary thank you so much for that compliment. 

I was never a professional machinist.  I was an inspector for a few years checking complex machined parts.  That gave me a solid foundation for “thinking outside of the box” with setups.  It also gave me an understanding of geometric relationships of features which is probably the biggest catalyst for my setups.

 I was also a CNC operator one summer in college and for a brief period (wife’s maternity leave) eleven years ago.  Those jobs exposed me to different workholding techniques.

-Bob

[90LX_Notch]

Oil Pan continued-

In order to get the required .275 radius a 5/16 boring bar was used.  The tool bit was set .118 above the boring bar’s centerline (5/16=.312, .312/2=.156, .156+.119=.275).  To make this setting, the bar was placed in a collet in the Atlas 618 lathe.  An indicator was set to zero on the diameter of the bar.  The carriage of the lathe was then moved to where the indicator touched the tool bit.  The bit was then adjusted.

Next, the boring bar was placed directly in the spindle of the BenchMaster mill and the radius was machined.  I’ve found this method to give a chatter free finish when compared to that of my boring head.

-Bob

[90LX_Notch]

Engine Block continued-

The Top Plate was made and assembled to the block.  A spigot was turned in a collet and the faceplate was installed on the Rivett 608.  The block was then placed on the spigot and clamped to the faceplate.  The Top Plate was then bored and counter bored.  A shop made plug gage was used for checking both diameters.  After the four bores/counter bores were completed, each Top Plate bore was indicated true and the bottom of the block was bored.


-Bob

[steamer]

That's looking great Notch!!!       It warms my heart to see it being done on a 608!!!

What's the bore and stroke on that?

Dave

[90LX_Notch]

Thanks Dave.  The 608 is my baby.

.750 x .875

-Bob

[gbritnell]

It's coming along great!

[RReid]

That's one sweet looking little engine block!

[90LX_Notch]

Thank you George.  I’ve always had immense respect for your builds.  Building this to print has increased that respect a great deal more.

-Bob

[90LX_Notch]

Ron-

Thank you for “tuning in”.  I don’t post much but check the site daily and follow most threads.  Nice job on the radial and congratulations on a fine runner.

-Bob

[Roger B]

Very nicely done     

[Vixen]

Hello Bob,

Thats some very impressive machining on the cylinder block. I am full of admiration of you guys who do it all on the handwheels.

Cheers

Mike