resurrected an old project 3 cylinder fairbanks (going to be a long build)

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Nice build you've got going on. Judging the piston shape, looks as if there's going to be some high compression in the future.

This is a photo of my dad starting a Fairbanks that he helped restore at his machine shop. I believe this engine is still operated by one of the local engine clubs.

This looks a lot like Chuck's model, but not exactly.

good morning guys :) (well its morning here)

craig i thought with the shape of the pistons it would be fairly high compression but there is a BIG combustion chamber in the head so the compression shouldn't be too high.

uni thanks for the picture :)

well i didn't get much time in the shop but i did get some work done.

first off i figured i had better have a look at the lower crankcase and see if i did everything to it the last time i worked on this beast.
i soon discovered that the mounting holes were not drilled so a quick set up in the mill fixed that problem


here is a pic of one of the mounting hole bosses


i centered it up using a dowel pin and my crooked eyes :big:


and here it is drilled to size, only 7 more to go


flipping the casting over on its side i then drilled the oil drain holes (2)


here's a close up of the drain hole boss (there is one on each side of the engine)


both holes are drilled, tapped and spot faced waiting for drain plug's to be made


that's all for now

thanks for tuning in :)


Hey, Chuck, back to your split mandrel for turning the connecting rod bushings. From the process you descried, I'm surprised that just threading in a common screw would cause the mandrel to expand. The screw isn't tapered? Does it hold pretty well?

hi guys :)

chuck: when i made the mandrel i just drilled a 5/16" hole in the end of the shaft and taped it 3/8" nc but i only ran the tap in about 3/4" and the taper of the tap give you the taper in the threads that you need. then just split the mandrel and run a 3/8" bolt or set screw in to the hole and it will expand the mandrel when the bolt hits the tapered threads left by the tap.
the mandrel works very well but the solder holding the bearing halves didn't work so well :'(

i managed to get some work done this week end (but not as much as i wanted to)

first up was a pair of brass oil drain plugs for the crank case.not much to tell about them, they are just a plain turning/threading job. then over to the rotary table to put the square head on them.


now in the beginning i said i would show all the good bad and ugly about this whole project......................well i wish i never said that..............but i did :p
i got to checking out the crank case and discovered the cam bore is way out of position and it drops from one end of the crank case to the other and is not parallel to the crank shaft.
the reason this is all wrong is because i must have had my head screwed on wrong the whole time i was working on this engine. :-[
just about every thing i did 6 years ago is wrong, and that is why i wish i never said i would show all of my mistakes, but i will show all .

first off the crank case had to have .032" milled off the top to bring it into spec. this picture shows the set up


and the end results of that little adventure


with that done i bolted the crank into place and then bolted the top of the crank case in place. then put the whole assembly onto the mill and set the crank shaft parallel to the milling table.
the next thing was to find center of the crank and locate everything from this point. some good news came out of all this, the cylinder bores are center to the crank as are the lifter bores. so i guess i got lucky on those 2 things.


as you can see in the above picture the cam bore (hole on upper left) is out of position in two directions and from one end of the crank case to the other it drops about...........well..........lets just say a bunch of thous. :-X so the next thing will be to set the crank case up on my lathe cross slide and by using a boring bar between centers i hope to bore the cam bearings in the right place.
i will take pictures of the whole set up as it unfolds.

i hope i am not boring you guys with all this babble and if i did not explain some thing well enough just let me know and i will try to do a better job.

as always thanks for tuning in Thm:

chuck foster said:
...<snip> i hope i am not boring you guys with all this ...

You're certainly not boring me Chuck. Looking forward to your setup and execution of the re-boring on the lathe.

rudydubya said:
You're certainly not boring me Chuck. Looking forward to your setup and execution of the re-boring on the lathe.


Me neither. :bow: :bow: I really, really like this model, comes close to the most fun you can have standing up. :p

Best Regards
thanks guys i appreciate the kind words it helps me stay motivated to see this project through. :)

rudy............i too look forward to the set up, how ever it will be ??? as i have no idea as to how i will do it. i will just keep at it till it is done then move on to the next part.

bob i don't know how to reply to your comment :big: :big: but i am glad you are enjoying this adventure. :)

again thanks guys and i will keep you all posted as this unfolds.

Although that error sounds like a lot, its not that bad, bore it oversize and bush the holes.

Make up the bushings to bush it with ahead of time, and leave them .09 undersize or so on the ID. Install the bushings with loctite and bore them in place with the same set up.

Looking good Chuck...always like this engine!

Here are some pictures of a full size 3 cyl. FM, located at Antique Powerland Museum about 40 minutes south of Portland.




Quite a big beast, and makes a beautiful noise when running at about 180rpm.
The crankcase door was deliberately removed so that observers could see the big bits going round.

The Emerald Isle
That's a good tip on the expanding mandrel. Never ocurred to me that the tapered tap could be used in that way. Thanks!

Very cool looking engine. Keep the updates coming.
well here we are 10 or 12 days latter and we finally have some thing to post about this project ;D

the cam journals were bored about 5 or 6 years ago and they were in the wrong location, so i had to fix that and this is how i did it.

first i had to re-bore the 2 outer cam journals in the right place. i squared up the upper crank case in the mill and re-bored them.
for some reason i only took one picture of the set up so here it is.


once the outer cam journals were in the right place i then made 2 brass bushings to fit in the holes. now these bushings will guide a 1/2" dia. piece of drill rod.
the drill rod will be the boring bar (held between centers in the lathe) that will bore the inner 2 cam journals. this engine has 4 cam journals.


as you can see in the above picture the crank case was held down by two 5/16 bolts with a piece of flat bar.
the rear bolt was threaded into the cross slide right were my rear mount tool holder goes. the bolt in front of the crank case was threaded into a plug i made that fits into the hole were the compound slide would mount. as you can see the crank case was set up on adjustable parallels.

here is a shot of the set up.


this next picture shows the boring bar and the cutter i made out of a broken carbide end mill. the end mill was 1/8" in diameter (i never throw broken end mills out)


now with all this set up done all i had to do was bore the holes.
the boring bar goes around with the cutter and the crank case (bolted to the carrage) goes back and forth while the cutter bores out the cam journals.

now with that done i bolted the crank into the lower crank case


then came the upper crank case with a short piece of steel in the cam bores, for the cam gear to fit on.


next came the crank gear .................. i was getting excited by this point :D


and then the cam gear was put in place ..................... holy crap it all fits :eek:



now with all that done i think i will make the cam bearings and then i will start on the dreaded cam .................. oh mr steve huck were are you, paging mr cam shaft maker extraordinaire

thanks for tuning in guys and mr fellows you are very welcome for the tap idea, but i cannot take credit for the idea as my good friend mr john crook told me about it years ago.

here is a video of the set up and boring of the cam journals


and the gears !!!


Great progress, and I love the Whoo Hoo! Very neat boring setup too.
Interesting operation Chuck. Thanks for sharing. How did you hold the cutter in the drill rod?


Every small step is another step closer to the finish line. Way to go. :bow:

Congratulations on getting that part sorted out. Is the cam going to be all one piece?

Here's the engine SteamDave posted pictures of, being started and run;


So now we can have a runoff between Chuck's finished model and the real thing! Great work and documentation Chuck - thanks for taking the time to show us how it's done.


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