Author Topic: Stuart No4 Casting Set  (Read 1391 times)

f350ca

Re: Stuart No4 Casting Set
« Reply #15 on: October 25, 2018, 08:02:49 PM »
Forgot to take pictures as I was machining the base and crank case.

f350ca

Re: Stuart No4 Casting Set
« Reply #16 on: October 25, 2018, 08:05:25 PM »
Started on the crank bearing caps. They're cast bronze. Machined to size and drilled the mounting holes, but left them undersized and reamed them to 1/8th for dowel pins to locate them to each other when I turn the outer profiles

f350ca

Re: Stuart No4 Casting Set
« Reply #17 on: October 30, 2018, 09:38:17 PM »
I assumed the crank was cast iron, wrong, was a low carbon cast steel, miserable to machine. Tried every shape in HSS I could think of and a couple of inserts, nothing gave a nice finish. In the end used a sharp point to reduce chatter, then filed and used emery paper to get it close, An aluminum lap brought it to final size.
Then made a jig that the crank went into with a light press fit, the jig put the throw on center.

f350ca

Re: Stuart No4 Casting Set
« Reply #18 on: October 30, 2018, 09:45:24 PM »
When I made the bearing caps I drilled and reamed the tops and bottoms to 3/8ths, then assembled them with a 3/8th dowel pin in the bore.
I clamped a piece of scrap to the mill table and drilled and reamed to 3/8ths to match the dowel pin. Then positioned the crank case between a collet and the reamed hole with the dowel pin. Brought an angle plate up against it and clamped it. Could then drill and ream to final size.
Happened to have a 1 thou over reamer, and lapped the crank to 2 10ths under. This gives me 0.0012 clearance on the bearings, it rotates nice but will that give enough clearance for oil?


f350ca

Re: Stuart No4 Casting Set
« Reply #19 on: November 06, 2018, 08:34:17 PM »
Paying projects have been hampering the engine progress but stole a bit of time.
Have 4 wee bronze bushings that supplied the material for a couple of parts. They came from a seismic vibrator, weigh about 50 pounds each.
They made the reversing handle and the arm it swings.

4GSR

Re: Stuart No4 Casting Set
« Reply #20 on: November 06, 2018, 08:38:42 PM »
Either that vice is a monster size or those are very small parts.

Nice work there.  Thanks for sharing.

Ken
Ken

kvt85

Re: Stuart No4 Casting Set
« Reply #21 on: November 07, 2018, 05:19:45 PM »
Looking good,   you are having to much fun.    I looked at one of those,   Could not afford it.  You are just a lucky dog.
Ken in SA TX

Jet 10x24 and Taiwan 10x24
Enco 30 mill
Sherline Lath and mill

f350ca

Re: Stuart No4 Casting Set
« Reply #22 on: November 07, 2018, 06:35:59 PM »
Not a monster vice Ken but the parts aren't too small for my old eyes either, a nice compromise.

Yes am defiantly having fun but don't think you can ever have too much. Will agree lucked into this one.

Greg

firestopper

Re: Stuart No4 Casting Set
« Reply #23 on: November 07, 2018, 07:39:15 PM »
Real nice progress Greg. 
Turn and Burn,
Paco

f350ca

Re: Stuart No4 Casting Set
« Reply #24 on: November 13, 2018, 08:12:56 PM »
Got a couple of days to play. Sure don't get much done in that time.
Made the links that move the quadrant for the valves then had to make 1/8th bolts for them. Made the heads 15/64 by .11 tall, looks about right I think.
Then made the quadrant on the rotary table, also cut the sliding block that the valve stem connects to at the same time.

chips and more

Re: Stuart No4 Casting Set
« Reply #25 on: November 14, 2018, 11:29:16 AM »
Looooookin gooooood!

pep

Re: Stuart No4 Casting Set
« Reply #26 on: November 14, 2018, 01:41:11 PM »
Beautiful workmanship, thanks for the ride .....

Pep

f350ca

Re: Stuart No4 Casting Set
« Reply #27 on: November 14, 2018, 04:17:07 PM »
Thanks guys,
Didn't review my post, looks like I double sent the one photo and missed the one of the linages.

firestopper

Re: Stuart No4 Casting Set
« Reply #28 on: November 14, 2018, 08:07:24 PM »
Nice work Greg, really liking the quality results.
Turn and Burn,
Paco

f350ca

Re: Stuart No4 Casting Set
« Reply #29 on: November 27, 2018, 07:43:08 PM »
This thing is taking up too much of my precious time. Bloody thing is addictive.
The intake ports were cored in the cylinder but the spacing was wrong, too far from the exhaust port, milled them into the correct position.
Then sliced off a piece of cast iron from some scrap and ground it to .1 thick and cut the ports in the correct position.