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Alistair Hosie
08-07-2003, 07:06 PM
what does a shaper do that cannot be done with a milling machine?.Alistair

G.A. Ewen
08-07-2003, 07:29 PM
Hi Alistair, I made a female spline on my old homemade shaper once. Don't think that can be done on a mill.

wierdscience
08-07-2003, 09:09 PM
Internal keyways longer than the stroke of a b-port keyseater,Last time I used the one at work it was to cut a 1"wide 10"long keyway inside of a 6"id stainless coupling hub,sure did come in handy.
On and unusual note we did use it to knurl some flat stock once,it was slow but it did work.
When we had one setup in the shop at work I used to setup pieces of flat stock in it to be planed flat,I could set the auto-feed and do something else while it quietly made chips.

Al Messer
08-07-2003, 09:18 PM
HSS tool blanks are a lot cheaper than End Mills!

Ian B
08-08-2003, 08:29 AM
Alistair,

Shapers can fire hot smoking swarf MUCH further than millers can...

But as Wierd says, set the shaper cutting (as long as it can run off the end of the work without crunching something) and go do something else in the shop. I love mine, and they're generally dead cheap.

Ian

SGW
08-08-2003, 09:05 AM
It's possible, with the right shaper setup, to generate true involute gear tooth forms so you can cut gears with any number of teeth with a single rack-shaped cutter.

Alistair Hosie
08-08-2003, 06:10 PM
I feel that although these became a bit unpopular for a while they are beginning to become popular again I keep lloking at a small one say a boxford or recently a elliot went for £200 UK what kind of money do the fetch second hand, (roughly). Alistair

G.A. Ewen
08-08-2003, 06:41 PM
I have seen them advertised in southern Ontario from $400 to $1000. I payed $600 for this 14" Elliot.
www.photobucket.com/albums/0603/GAEWEN/091d0959.jpg (http://www.photobucket.com/albums/0603/GAEWEN/091d0959.jpg)

Al Messer
08-08-2003, 08:04 PM
G.A. You have a BEAUTIFUL hunk of old iron!! Give it a big hug for me!!

Al Messer

Alistair Hosie
08-08-2003, 09:49 PM
G A Ewen see this one I missed and only £200UK 2549137985 see this on ebay.
Al I hug it every day http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif

Al Messer
08-09-2003, 05:45 PM
Alistair, if you didn't live so far away, I'd invite you to come over tonight, and I'd let you play with my South Bend 7 to your hearts delight. What I like about a shaper the mostest is that they can reduce chunks of scavanged metals down to a needed size a lot quicker than a hacksaw and file, plus as I said before, HSS tool blanks are a lot cheaper that End Mills!

Al Messer
08-09-2003, 05:48 PM
SGW, making gears is one of those "I'm gonna do that dome day" projects I want to try on mine. Can you use an existing gear to grind the cutter to the correct shape and size?

G.A. Ewen
08-09-2003, 08:07 PM
Al, as to gear making "i'm gonna do that some day" to. Here is what I have planned. In the April 1999 issue of Machinist's Workshop there is an artical by John A. Cooper called "Spur Gears and Pinions". In it he shows how to make a rotory gear cutter with the profile of a rack and then discribes in very clear terms how to use it. (good pics also) My friend Andy and I tried it and were very pleased with the results. I would now like to try designing a cutter for the shaper that would work along the same principals. I should be able to get to it sometime in November.

SGW
08-09-2003, 08:23 PM
Al, understand, I've never actually DONE this....

But, what you want for a cutter is a rack tooth profile -- straight sides, sloped (I think) at the pressure angle of the gears you're making.

Since with an involute form, any gear of a given size/angle will mesh with any other gear, including a rack, the theory is to make the shaper cutter the "rack" that the gear (being cut) is meshing with. Then "roll" the gear blank under the cutter at the proper rate.

There was an article in Model Engineer years ago on how to do this, but I haven't a clue now what issue it was.

gvasale
08-09-2003, 08:44 PM
FWIW, a couple of years back, I had someone who runs a cutter grinding service examine the profile of two pinions I needed to make on an optical comparator. He dimensioned the angles and the radius both at the end of the tooth, and the base of the tooth. He ground a single point tool which I dragged across a suitable blank held in a lathe. Since this was not a generating operation, and in this case not an involute profile, it matched very closely what would be produces as if one were using a milling type of gear cutter.

If you have good layout ability and could grind the appropriate form this method would work in a shaper too, indexing the blank for each tooth.

Oso
08-10-2003, 12:39 AM
It does work, I've done it, using a mating gear as a form guide for grinding.

A change gear was used for indexing.

Gears work great.

Grind until no light shows around your tool when checking against the "master" gear. This does not account for wear of the "master" gear, but it makes a gear that works.

Just don't do what I did the first time, I did not leave any relief on the cutter, it was really draggy and didn't cut cleanly.