Author Topic: Stuart No4 Casting Set  (Read 699 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