south bend 9B for gunsmithing

[uscra112]

??? A gantry machine is not a planer. Nor is a planer mill. If there's new planers being made, I musta missed 'em.

I had a long and sordid history with aerospace gantry mills when I was in the machine tool rebuild biz. The Onsrud we did was good. Cincinnatis were prime, but I never got to work on one. The worst ones were Shin Nippon Koki. (SNK) Junk when they were brand new.

No, I lie. The worst ones were the first rebuild project I was ever put in charge of. Two 70' Farnhams. Gantry machines made during the Korean War by a company which was actually a specialist in woodworking machinery. Took me almost two years to get them sorted out. The fact that my predecessor had sold the Air Force on some insanely stupid modifications didn't help.

</rant>

Kinda OT ain't we! From bench lathes to machines bigger than a railroad car!

[M-Tecs]

Maybe I am using the wrong terminology? It's been my understanding that when using a single point non rotating tool it is a planer. When the milling heads are attached it becomes a mill. I always thought the little Bridgeport Heads looked out of place on the massive Cincinnati's. Even on the little ones like this one. http://www.belmontmachinery.com/inve...i-hypro-planer

On the new 120 foot CNC Gantry Planer/Milling machine that does have a planer type single point tool attachment. It is with a moving bridge style.

[uscra112]

That's a planer, (mill) sure enough. The table travels. A gantry machine has a fixed table, often huge. and the bridge (the gantry) travels along it on ways. The big aerospace shops love them. They can set up a whole family of fixtures, maybe for parts only a few feet long, and send the gantry to the fixture. Meanwhile an operator can be unloading/loading a fixture on another part of the stationary bed. Because they produce parts in "ship sets" (i.e. only as many as needed for one airplane), the fixtures stay in place for years at a time. This is undoubtedly becoming less common now that composites are taking over in airframe design. Although the idea may now be used for the "tape layers" that build up parts on a form. I've been away from it all for over twelve years, and haven't kept up.

Here's an unusual gantry machine used on the F-35 program at Lockheed. It has the gantry ways about 15 feet in the air, to keep them away from the abrasive swarf generated when machining composites.

https://www.mmsonline.com/articles/c...g-for-the-f-35

Late in the article it mentions an equally huge Zeiss CMM that does the inspection. That's my baby. I spent a whole winter as site manager installing that thing. The Droop & Rein guys hated us. Among other things it was we who proved that the foundation under the FOG machine was sinking!

[M-Tecs]

That's a planer, (mill) sure enough. The table travels. A gantry machine has a fixed table, often huge. and the bridge (the gantry) travels along it on ways.

That's were I get confused. Your definition is what I was taught in the late 70's but in the the mid-80's the company I worked for had both types and they called both types planers. Both types had vertical and horizontal milling attachments in addition to the single point holder attachment.

The current adds for the large twin column machines call them Gantry Planer Mills regardless if the table or the bridge moves?????

My background was mostly fixtures and smaller specialty machines but a good buddy of mine was a planer operator.

Thanks for the link. Zeiss CMM's of that size are incredible machines.

[W.R.Buchanan]

The big gantry mills are used for machining wing spars for airplanes. I have seen ones at Boeing that are 150 feet long+.

Shapers are good for making long grooves in pieces that you can't readily broach. They are kind of obsolete but still fun to watch people dodging the hot chips that fly off them. You learn quickly where not to stand.

Randy

[Scrounge]

That's were I get confused. Your definition is what I was taught in the late 70's but in the the mid-80's the company I worked for had both types and they called both types planers. Both types had vertical and horizontal milling attachments in addition to the single point holder attachment.

The current adds for the large twin column machines call them Gantry Planer Mills regardless if the table or the bridge moves?????

My background was mostly fixtures and smaller specialty machines but a good buddy of mine was a planer operator.

Thanks for the link. Zeiss CMM's of that size are incredible machines.

I think where you're getting confused is between shapers/planers and milling machines. Shapers and planers use a single point tool much like a lathe tool to do their cutting. On a shaper, the cutting head that holds the tool is on a reciprocating ram, and the table does not move during the cutting stroke. On a planer, the cutting head is on a gantry that doesn't move during the cutting stroke, while the table does the moving.

this is a video of a very small planer: https://www.youtube.com/watch?v=ez2xebWiN5o

this is a video of a very small shaper like the one I have: https://www.youtube.com/watch?v=bqqArCxkMtc

This is a video of a moderately sized gantry mill, which can have both the table and the gantry moving at the same time, and some of them can have multiple cutters running likewise: https://www.youtube.com/watch?v=MgH7zf-xmE8 They are amazing machines! My budget will not ever allow me to have one... What do they call that? Champaign taste, beer budget!

Times change, language changes, and the only universal constant is change. Shapers and planers are obsolete, except for certain things they do better than anything else. Old joke about shapers is that you can make anything but money with a shaper. And that is why they're obsolete. In the 1st World, anyway. Still in production in the 3rd World because you can set and forget them, and don't need computers to run them. In the 1st World, they're still used in some very few specialty shops, and among aficionados. I know of one commercial shop in the Pacific Northwest that has shapers on their production floor, and in a little private museum, as the owner collects and restores antique machine tools.

One thing a shaper is good for that is difficult to impossible to do on a mill is making internal splines. Most places use broaching and the tooling is ferociously expensive relative to a single-point tool like a lathe tool.

Bill

[uscra112]

One of the reasons for my abiding interest in 19th century guns is the fun of trying to sort out how they were machined. In several instances a shaper would have been the only way. Guns aren't designed that way anymore. And authentic replicas can't be made unless you have a shaper. The design has to be altered otherwise.

Broaching is another process used a lot then but not so much today. But sometimes it is the right way. I can cite a case where Ford was talked into abandoning broaching to finish cylinder head joint faces for a V-6 engine used in early Windstar minivans, in favor of milling. The result was a face that wasn't flat, and a round zillion blown head gaskets that had to be fixed under warranty. I was unlucky enough to be the guy that identified the problem. The machine tool builder hated my guts forever after.

[farmbif]

I love the old manual machines and seem to constantly be on the lookout for old American made south bend, LeBlond, monarch and Bridgeports wells-index and others guess its just a habit I can't give up. never did learn how to use the newer digital control machines

[uscra112]

Before CNC, machines had to be inherently accurate. Straight, flat, square and parallel, we used to say. Making accurate leadscrews was an art in itself.

Computer comtrollers have a raft of registers that apply corrections for known mechanical errors, and the builders no longer take such care. They just set up the laser interferometer and calibrate the errors away. A problem is that the machines aren't really stable, so they require periodic recalibration.

(Old machine tool rebuilder here, saw this happening with my own eyes in the '70s and '80s. At one point I nearly bought a laser system with the intent of becoming a recalibration contractor; there's that much business out there.)

A rare book that is a good read is "The Foundations of Mechanical Accuracy" by Wayne R. Moore.