The "Little Pearl" Single Cylinder Marine Engine

[Flyboy Jim]

Bill..... you started this thread around the time I took my "time-out", so am just starting to get caught up (I'm on page 5). I always enjoy your build threads and seeing how you machine parts on your Sherlines .................and this thread is no exception!

Jim

[Flyboy Jim]

OK Bill, I'm all caught up now on this thread. Well done.    Even though it's more work.........it seems really rewarding to carve those parts out of cast bronze. I know I've enjoyed doing that on my P & W build.

Anyway............thanks for waiting for me to get caught up..............you can carry on now!   

Jim

[b.lindsey]

Thanks Jim!  Shop time has been scarce lately but hope to find a little time over the weekend.

Bill

[b.lindsey]

This weekend I have been playing around with one of the two main bearing cap castings. As you will see the casting is a lot bigger than the final part requires so it was slow going on the sherline but still very do-able. This first photo shows one cap machined down to its final overall size compares to the original casting. Once I got the ends and sides milled down to their final size (photo 2) I flycut the bottom surface to mate with the base eventually (photo 3). With that done, back to the mill to spotface and drill the four mounting hole (photo 4). Photo 5 again shows the finished part in relation to the original casting, and photos 6 & 7 show the finished cap. The final boring will not be done for the crank bearings until the caps are installed on the base.  The top of the caps will be left as is to add some of that "castingness" to the overall look

Bill

[crueby]

Looking good!

Are you going to be using hex head bolts or studs/nuts in the final engine? If so, are those flats around the bolt holes large enough for the hex?

 

[b.lindsey]

Undecided yet Chris, but leaning towards hex bolts. The threads are 10-32 in the  base, the spotfaces were done with a 5/16" end mill. I may try making a bolt out of 1/4" hex brass to see what it looks like. Can always use 10-32 SHCS's in stainless as well which would fit with a marine engine. The SHCS shown is just a 10-32 from my sherline hardware. Granted hex cap screws would look better.

Bill

[NickG]

Looking good Bill, lot of castingness left with the spot facing. Looks the part.


Sent from my iPhone using Tapatalk

[b.lindsey]

Thanks Nick. The vase will be machined all over so something needed a bit of casting texture. The pedestal should be another source of said "castingness" but have yet to do anything on that front.

Chris, I turned up a doomed hex cap screw out of 1/4" brass and I think that will work well and fits the spot faces well and there is even room to tighten them with a hex driver. I'll take a couple of pictures later and post them. Glad you asked the question as these can all be turned up even in little bits of shop time. Just need to check the drawings and see what length they need to be now.

Bill

[b.lindsey]

Here is a dome head hex cap screw turned from 1/4" brass hex stock. I think given that there are 4 screws holding the cap on and that it only has to hold the bearing in place, I think this will do. Picture one shows the shoulder of the screw and photo two shows it in place in the bearing cap.

Bill

[crueby]

Those look great! And checking that the driver or wrench will fit is always something I forget to do!

[b.lindsey]

I guess the decision is made then Chris

Bill

[10KPete]

I like the use of the reduced head size. That makes it all fit nicely.

 

Pete

[b.lindsey]

Thanks Pete, it is a bit smaller than the OD of a 10-32 SHCS but close enough to look "right" I think even so.

Bill

[Dave Otto]

You get my vote Bill, the dome head bolt looks perfect!
Nice progress.


Dave

[90LX_Notch]

Yes, the domed head looks great.  Great progress as usual Bill

-Bob