Going down the babbitt hole

[Hickory]

[Hickory]

So the plan is to drill and pin the cracks. The machine shop just finished that up and I'm picking up the block tomorrow. Pictures will be posted tomorrow.

[Sniper]

Not a good place for a crack.  Not sure how you can pin a crack like that though, but I am not a machinist, just interested in knowing how it's done when the crack has a 90 into the port like that?

[Hickory]

I have done this with boat engines that have froze and cracked. The machine shop is doing this one ase they can machine the surface after.

[DonaldSmith]

The nation's Capitol used pinning to repair the cast iron dome. 

How could a bolt possibly hold two pieces together, you may ask.  I wondered myself.  The secret is in the threads. 

Most threads have the same slope on both surfaces.  Drill and tap a hole on the joint between two pieces, and screw in the bolt. the pieces can pull apart.

Imagine a Christmas tree, with all the branches sloping up.  The threads of these bolts slope "up".  They can't pull out of the surrounding material.    I can't imagine that this would be as strong as the un-cracked material it self, but it

is good enough for the Capitol. 

 

(Spelling lesson from Fr. Flanigan's spelling drill, way back in the Second Grade: 

The building: CAPITOL.  The city: CAPITAL.)  

   

[Sniper]

I know how pinning is done, in general.  Just interested to see how they pin the vertical crack, especially if it's the exhaust port.

[Hickory]

Intake port 

[Dodgeb4ya]

I like "LOCK-N-STITCH" .http://www.locknstitch.com/index.html

 Expensive but always will do the job 100% by a competent person. 

I had a 413 MaxWedge job..the block was cracked down both sides

I had to save all casting ribs and raised letters/numbers matching #'s car and engine. Grind down and hide the repaired areas.

L&S uses a reverse thread design and special thread tooling that pulls the crack tightly together.

Most any accessable areas can be pinned.

Older systems used tapered threaded pins...these could slightly expand and stress the repaired crack if not done right.

 

Edited June 8, 2023 by Dodgeb4ya

[Los_Control]

I like the fact the machine shop is fixing it .... Sure they wouldn't touch it unless they were confident.

Gives you more time to play with other things   

[Hickory]

Sniper I have no doubt you know how pinning is done, that's what I like about you. Your attention to detail.  But for other members I have explained what pinning is.

[Hickory]

This is a lock and stitch Andy. And that's what I have done myself, but for a head surface and valve pockets I will let them do it.

[Hickory]

I just received my block will get pics soon. Sniper they did horizontal first then used smaller ones on the vertical and went into the other pins so it is actually a stronger repair since the pins interlock two different ways

 

[Hickory]

 

 

[Hickory]

[Sniper]

Thanks for the clarification.  I learned sometime new today, who's says an old dog can't lol

[Hickory]

Me too, I learned what an empty pocket feels like.lol

[Hickory]

Not much time left to play with things. I must send out the thrust bearing now it is bored to have the radius cut and the thrust width ground. While that takes place painting will commence and then camshaft installation.

[Hickory]

Paint......

[Hickory]

Camshaft and valves are in. Tomorrow valve adjustment and water pump.

[Hickory]

Indexing the cam gear took a minute, it can go on 4 different ways. I know the gear isn't tight, it's coming back off.

[Hickory]

[Hickory]

So looking at my block I did some research on the date. My block was built three weeks prior to black Tuesday and the stock market crash of the great depression. I find it amazing that a company (DeSoto) not only survived, (as a new division) but thrived.

[Hickory]

[Hickory]

Dated 10/7/29

[Hickory]

Head studs, intake studs.