Straightening a 10 inch diameter Rudder stock.

jackie schmidt

jackie schmidt

New member
https://www.google.com/url?sa=t&rct...=lgk8NOTJeTw&usg=AOvVaw2jS7DR4caMsfdlE8PB49CS

https://www.google.com/url?sa=t&rct...=1UwtYfFMAbU&usg=AOvVaw1eDp9Ap5mxjbVx8JB-c6Of

This came in yesterday on a emergency dry docking. I set it up and straightened it.

This is one our more lucrative services, since few shops have the equipment to precision straighten this large of a piece. The rig you see hanging is our 700 unit.

It took me and one of my men about Three hours to set It it up and straighten it.
 
Last edited:
Jackie,
The before and after shots are great..but if you do it again I would like to see a little of the process.
Thanks


Mort
 
dmort said:
Jackie,
The before and after shots are great..but if you do it again I would like to see a little of the process.
Thanks


Mort
Click to expand...

Well, it’s kinda proprietary. We will not even let customers watch us do this.

But if you take a look at that straightening rig, you can get an idea how we do it. The arms are adjustable, allowing us to put tonnage exactly where we want to apply it, making the piece bend in the correct spot. Using one of these is as much of an art as anything.


We have 4 of these rigs in different sizes. A 150 ton, a 350 ton, a 500 ton and this one. They operate on 10,000 psi maximum. The arms and strong backs are made from T-1 plate.

We designed and built these ourselves. I refer to the process of straightening as applying Precision Tonnage.
 
Last edited:
cool !

jackie schmidt said:
Well, it’s kinda proprietary. We will not even let customers watch us do this.

But if you take a look at that straightening rig, you can get an idea how we do it. The arms are adjustable, allowing us to put tonnage exactly where we want to apply it, making the piece bend in the correct spot. Using one of these is as much of an art as anything.


We have 4 of these rigs in different sizes. A 150 ton, a 350 ton, a 500 ton and this one. They operate on 10,000 psi maximum. The arms and strong backs are made from T-1 plate.

We designed and built these ourselves. I refer to the process of straightening as applying Precision Tonnage.
Click to expand...
How close do you need it to be?
 
WallyDog said:
How close do you need it to be?
Click to expand...

It an item like this, “visually straight”. Keep in mind, the rudder blade welds onto the part below the bearing journals. We will reweld and remachine the worn bearing journals truly straight.

When straightening propeller shafts, it’s a different story. You are now working in thousandths of an inch.

Since we rebuild shafts on a daily basis, we use these straightening rigs all the time. All of our machinist are well trained in how to use them.
 
Last edited:
Amazing hydraulics

jackie schmidt said:
It an item like this, “visually straight”. Keep in mind, the rudder blade welds onto the part below the bearing journals. We will reweld and remachine the worn bearing journals truly straight.

When straightening propeller shafts, it’s a different story. You are now working in thousandths of an inch.

Since we rebuild shafts on a daily basis, we use these straightening rigs all the time. All of our machinist are well trained in how to use them.
Click to expand...

I used and maintained straightening fixtures at Caterpillar Tractor Inc for wheel loader frames and lift arms. Weld draw was the culprit and had to be forced into usability before machining. 10,000 psi behind a 6 inch hyd cyl. bore would do it easily. I was amazed when I first started working there as to how much power they produced. I had guys that operated them daily and they were getting frames 12 foot long x 8 foot wide straight and square to within 1/32.
 
What about?

Jackie! Just think, if you was to adapt this same technique to straighten out all those crooked barrels... we could take indexing out of the chambering process! ;-)

Keep safe my friend!
Scott
 
Jackie,

Does the rudder stay in the lathe during the straightening process or is it fixtured elsewhere?

Justin
 
Thanks for sharing your work to me it is always overly interesting. Hard to believe one can take that much bend out of such a large piece. Do you happen to know what it was that caused it to bend. And what type of material is the shaft made from.
 
Louis.J said:
Thanks for sharing your work to me it is always overly interesting. Hard to believe one can take that much bend out of such a large piece. Do you happen to know what it was that caused it to bend. And what type of material is the shaft made from.
Click to expand...

Rudders and shafts get bent due to hitting objects in the water, running aground, or getting pushed into the bank. Inland Pushboats lead a hard life.

Prop Shafts and Rudder Stocks are made from mild steel, with Stainless Steel weld in Way of the bearing journals and taper fits.

Small vessels often use solid stainless for shafts, usually 17-4 in H1150 heat treat. We by it in ground and polished bars ready to machine the tapers on each end. The brand name got this type of shafting is Aquamet 17.

https://www.aquamet.com/aquamet-17
 
Zebra13 said:
Jackie,

Does the rudder stay in the lathe during the straightening process or is it fixtured elsewhere?

Justin
Click to expand...

We do it right in the lathe . Look at the huge piece of equipment hanging by the crane at the end of the rudder stock. That is the straightening rig. I took the video before we moved the rig over the stock.

It exerts no force on the lathe at all. All of the tonnage applied to the piece is totally contained within the straightening rig.
 
Last edited:
jackie schmidt said:
We do it right in the lathe . Look at the huge piece of equipment hanging by the crane at the end of the rudder stock. That is the straightening rig. I took the video before we moved the rig over the stock.

It exerts no force on the lathe at all. All of the tonnage applied to the piece is totally contained within the straightening rig.
Click to expand...

Jackie,

Got it, and thank you. I missed the hangy-down supports at first glance. Pretty darn slick!

Justin
 
Butch Lambert said:
Thanks Jackie. Some on that Forum are like some on the shooting forums.
Click to expand...

A couple of those guys are a lot like some on our Forum, for reasons known only to them, they get their panties in a wad.

It leaves me thinking that many don’t have a clue about The Machine Shop Business.

It is enjoyable reading.
 
You must log in or register to reply here.
Back
Top