GDB Inline 4 Cylinder OHV I.C.

[Craig DeShong]

Very nice work Bob. 

[scc]

Absolutely beautiful machining Bob         My attempts at accurate handwheel turning are far below yours.......inadequate concentration          Love this build             Regards     Terry

[90LX_Notch]

Thank you Craig.

Thanks Terry.  I have notes by the machine indicating the direction the part is being machined based on what the numbers on the dials are doing. 

 My notes look like this:

Cut to Left X minus
Cut to Right X plus
Cut to Back Y minus
Cut to Front Y plus

-Bob

[fumopuc]

Hi Bob, very impressive.

[90LX_Notch]

Thanks Achim for your continued support.

-Bob

[90LX_Notch]

Main Caps-

I decided to take a little deviation and start on the main caps.  The rough shape was milled and then setup on an arbor in the lathe.  A Dremel was used to profile the required .275 radius.  I've posted about this technique before, but in a nutshell, the Dremel is set on the tangent and is run back and forth until the profile is produced.

Next, the profiled bar was setup in the mill and a .014 slitting saw was used to slice off the caps.

The caps will be drilled in the mill.  The same fixture plate that was used for locating the block will be used.  A .250 pin that sits in a radiused groove in the fixture is used to locate the caps.

-Bob

[90LX_Notch]

Well it’s been close to a year without any updates.  I did continue to work on this but just didn’t post anything for some of the reasons that were brought up in the “Lack of response to posts” thread.  But, a major factor was that my technology had become very outdated.  It was ten times harder to move, convert and post pictures.

 The attached picture is a “family” shot.  The oil pan and main caps are done.  The timing cover is done.  The tappet cover is done and the water pump is half done.

I do have some pictures of each part being machined if there is any interest. 

-Bob

[Vixen]

 

Just to let you know it's looking good.

Mike

[Roger B]

That's some machining to be proud of     

I am interested in function, I don't have the patience for finishes like that 

[90LX_Notch]

Thanks Mike, knowing your work, that is a great compliment.

Thank you Roger.   The finish isn’t all that hard to achieve. Sandpaper to remove tool marks and green Scotchbright for the final finish.  I try keep the same stroke direction to give a grain appearance.

-Bob

[kuhncw]

Bob,

Nice work.  Photos of a few more parts being machined would be interesting.  I always learn from the setups others devise to hold parts.

Chuck

[Admiral_dk]

Looks really good to me + nice to see that you still progress with this engine.

You mention that the finish is only 'sandpaper' - but it still requires the correct technique or you end up with a lot off lines criss crossing each other in odd angles ... 

[gldavison]

Beautiful work Bob. I begin to wonder if you were still going to work on this. I understand about life getting in the way of the hobby. I check in every day hoping to see some progress.
I'm with Rodger on the finishing part. I'm just interested in seeing the work run when I get done. Maybe if I live long enough the better finishes will come along.

Gary

[90LX_Notch]

Thank you Chuck.  I will start posting pictures.

Thank you Admiral for your continued support.

Thank you Gary.  Hopefully, I can get some momentum going.

-Bob

[90LX_Notch]

Main Caps continued-

A .250 diameter pin was placed in a collet.  A driver was threaded onto the Atlas 618 spindle and a previous attempt at the main caps was placed on the .250 pin.  A lathe dog was clamped onto the assembly.  This setup created a fixture to screw the main caps onto for facing.  The caps were then faced on both sides to the proper width while maintaining alignment with the caps center line.

-Bob