Using what you have on hand.

[jackie schmidt]

I have decided to convert my Rail Gun Barrel Block to front a V to a round non metallic sleeve.

I could do it several ways, but decided to do it on our big Lucas Horizontal Boring mill.

I thought you all would get a laugh out of an obvious exercise in overkill

But you use what’s handy for the job on hand.

http://benchrest.com/attachment.php?...1&d=1574433215

[liljoe]

What material are you going to use for the sleeve? I have asked several people about this and they all seem to have different ideas on it. I was going to try one out last year but didn't get around to it. I also didn't want to disturb my rail since it had the best barrel I have ever owned on it.

Joe Hynes

[Lee Martin]

Nothing wrong with that Jackie. How much horsepower does that mill have? I know a lot of those old Lucas horizontals were 15hp+.

I almost did a V block on my rail but went the delrin sleeve route instead. V's are nice for running different barrel diameters, but I chose to make a few sleeves (1.25, 1.35, and 1.45)

-Lee
www.singleactions.com

[Butch Lambert]

I made the mistake of using a light press fit on my Acetal sleeve. It slipped. Put a small slit in it and it was fine.

[jackie schmidt]

What material are you going to use for the sleeve? I have asked several people about this and they all seem to have different ideas on it. I was going to try one out last year but didn't get around to it. I also didn't want to disturb my rail since it had the best barrel I have ever owned on it.

Joe Hynes

I am going to try a woven material called Marine Blue. We use it a lot fo non metic bushings.

I have on hand Delren, CIP, ( another woven material), Thorplas, UHMJ, Nylon and Micarta. I thought I would try this.

http://benchrest.com/attachment.php?...1&d=1574456479

[dmort]

Jackie,
Great pic that brought back memories of the shipyard. If you did it on this floor mill ,and I BET YOU COULD...that would be some serious overkill !

Mort

[alinwa]

Jackie,
Great pic that brought back memories of the shipyard. If you did it on this floor mill ,and I BET YOU COULD...that would be some serious overkill !

Mort

That's so cool..... I didn't even know "floor mills" existed until this pic. In retrospect it's an obvious solution for large work and once I'd thought about it I searched the innertube and sure enough, there's one not 5 miles down the road from me. And many more between here and the coast.....

So much I don't know that I don't know what I don't know

thank you

[jackie schmidt]

Jackie,
Great pic that brought back memories of the shipyard. If you did it on this floor mill ,and I BET YOU COULD...that would be some serious overkill !

Mort

Nice picture.

That is a large rudder that they are machining. I have actually repaired a rudder that large, (it weight 35,000 pounds), but we did it with portable boring bars.

The pintal pin had come loose and had wallowed out the fit. ( that is located in the boss just forward of the square access hole in your picture. We rebored it in alignment with the upper stock fit. We repaired the pin by welding it up with submerged arc stainless and remachining it.

[Wayne Shaw]

I am going to try a woven material called Marine Blue. We use it a lot fo non metic bushings.

I have on hand Delren, CIP, ( another woven material), Thorplas, UHMJ, Nylon and Micarta. I thought I would try this.

http://benchrest.com/attachment.php?...1&d=1574456479

Jackie, you do realize if you win one match with it, everyone will want one!

[dmort]

That rudder is from the aircraft carrier Midway. Rudders coming into the shop had the bore built up with weld. How they did that I don't really know. I don't think we used carbide because of the interrupted cuts getting through the weld.

The boring bar and fixtures were made inhouse used a simple star feed for both the upper and lower segments.

Large work like the rudder would role into the shop on small railroad flatcars. The overhead crane and a rigger would move the work to the proper machine.

I never did a rudder setup which is time-consuming and took two machinists. Once you start cutting it's a one man show. That's where I came in on the night shift.

The taper was built into the boring bar. If I find a pic I will post it.

Mort

[jackie schmidt]

Mort, I have build boring bars that cut the taper in those large rudder frames.

Back in the ‘80’s we had a contract with Halter Marine in Mobile to do the machine shop work on five 20,000 HP sea going tugs. The rudders were built on a frame that had a 40 inch long taper fit at the top, the top was 14 inches diameter and tapered at 1 inch to the foot. It had a 3 inch wide key way.

That contract is the reason we bought that big LeBlond Lathe we are now getting rid of. The main prop shafts were 20 inch diameter, about 18 feet long, with a 36 inch diameter flange forged on one end.

I learned a lot doing that job. We even built a small taper cutting boring bar to do the tapered coupling bolt’s. They were a nominal 3 inch diameter on the big end.

It’s hard to believe that was over 30 years ago.

[JerrySharrett]

That's so cool..... I didn't even know "floor mills" existed until this pic. In retrospect it's an obvious solution for large work and once I'd thought about it I searched the innertube and sure enough, there's one not 5 miles down the road from me. And many more between here and the coast.....

So much I don't know that I don't know what I don't know

thank you

Al, the machine Jackie is using is called a Horizontal Boring Mill HBM. They are common in big shops and come in several configurations. They are made by Lucas, Cincinnati-Gilbert, Bullard, Giddingx&Lewiss and a few others.

The last one I was a Project Engineer on was a Giddings&Lewis Floor Type. It took 128 cubic yards of reinforced concrete for its foundation and could take an 85 hp cut 12’ above the floor. It was CNC. Had 12’ xaxis, 12’ yaxis, 6’ zaxis, and 5’ waxis.

This was in 1995 and the US had become spooked by the environmentalists we had to get the castings poured in Japan.

.

[Butch Lambert]

If you like large machines, go to Commerce Grinding's website.
http://commercegrinding.com/photo-gallery.html
When I visited I really like their 300inch diameter capacity surface grinder that has a 12ft vertical capacity.
10"X30ft centerless grinder
36"X168" OD grinder
80"X300inch toolroom surface grinder.
They do a lot of regrinding lathe ways.

[Zebra13]

Mort, I have build boring bars that cut the taper in those large rudder frames.

Back in the ‘80’s we had a contract with Halter Marine in Mobile to do the machine shop work on five 20,000 HP sea going tugs. The rudders were built on a frame that had a 40 inch long taper fit at the top, the top was 14 inches diameter and tapered at 1 inch to the foot. It had a 3 inch wide key way.

That contract is the reason we bought that big LeBlond Lathe we are now getting rid of. The main prop shafts were 20 inch diameter, about 18 feet long, with a 36 inch diameter flange forged on one end.

I learned a lot doing that job. We even built a small taper cutting boring bar to do the tapered coupling bolt’s. They were a nominal 3 inch diameter on the big end.

It’s hard to believe that was over 30 years ago.

Jackie,

I'm not following you on the boring bar that cuts a taper, I'm assuming, without using the compound. Is this boring bar a form tool of sorts?

Justin

[jackie schmidt]

Jackie,

I'm not following you on the boring bar that cuts a taper, I'm assuming, without using the compound. Is this boring bar a form tool of sorts?

Justin

This is a simple sketch portable bar to bore a large diameter taper in a large frame.


http://benchrest.com/attachment.php?...1&d=1574720443

The tool block channel is milled parallel with the taper. The fitted tool block travels down the channel, advanced by the screw. The star feed hits a bar every revolution.

Simple, but effective.