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View Full Version : Internal keyways on a shaper? How Practical?



LKeithR
07-28-2012, 03:41 PM
Trying to get a little machine shop up and running. My brother and I have been in business over 40 years; most of our work being welding related. We had a decent machine shop for about 10 years in the 80s and 90s but, due to a downsizing move, got out completely in '98. We've missed the machining component of the business and a little over a year ago bought a decent lathe and mill. Our hope is to supplement the work we're doing now and give the business a little broader scope. When I do finally quit the machines and tooling we've accumulated will form the basis of my home (retirement) shop.

We've been slowly adding tooling and accessories and our next target is to add the ability to make internal keyways. I see two options: 1) Go with broaches and a press, or, 2) Set up a small shaper to do the work. At the moment we have nothing so we're starting with a clean sheet of paper.

We've located a small shaper (European, 8" stroke) for a reasonable price ($750). It would require some fixturing but I have a pretty good idea how to tackle that. How difficult, or easy, for that matter, is it to cut internal keyways on a shaper? We did lots of keyway broaching in the old shop so I know what's involved but without any broaches and bushings and with no suitable press I can see that we could easily spend a couple grand to get set up properly.

I used the term "suitable" because we do in fact, have a press. It's a bit of a clunker, however, and only has about 6" of stroke; not very convenient for broaching. I'd like to have something with about 18" - 20" of stroke--it makes life a lot easier.

A couple other points: Our (small) shop is filling up and finding a hole for the shaper will be an issue. If it's the right way to go we can make it work but it will mean sacrificing a bit of space for something else. And as far as the broaches go, to save some up front money, we can add them individually as we need them. They're readily available locally so if we get a job in that requires a keyway there shouldn't be any delays. The downside, of course, is that we'll spend a lot more for individual broaches and bushings than we would if we just bought a kit.

I'm curious to know how others have approached this situation.

John Stevenson
07-28-2012, 04:44 PM
What sort of mill do you have ? Can you get a slotting attachment for it.
Main problem with doing keyways in a shaper is lack of daylight, you are normally working blind and the work is often off the table when mounting due to the length of the slotting tool.

Dr Stan
07-28-2012, 05:20 PM
Main problem with doing keyways in a shaper is lack of daylight, you are normally working blind and the work is often off the table when mounting due to the length of the slotting tool.

I've cut keyways in a shaper and they are a PITA, even on a vertical shaper (but not as bad). IMHO you'd be better off with an arbor press & a set of broaches. You can have the keyway finished before you'd even have the shaper set up.

firbikrhd1
07-28-2012, 05:38 PM
I too have cut keyways in a Shaper. From the standpoint of a hobbyist, my findings are that using a broach is faster, however, if you seldom do them a Shaper may be a good way to go because it is useful to do other operations. If I had to do them often I would probably invest in a broach, but since I have a Shaper and it can cut splines, square, hex or other polygons, make things flat and cut gears and racks when properly set up, that is my method of choice.

oldtiffie
07-29-2012, 04:08 AM
Use a small arbor press on a hydraulic press as the vertical adjustments on the press will give you plenty of vertical space:

http://i200.photobucket.com/albums/aa294/oldtiffie/Hydraulics/Hydraulics1.jpg

John Stevenson
07-29-2012, 06:55 AM
Use a small arbor press on a hydraulic press as the vertical adjustments on the press will give you plenty of vertical space:

http://i200.photobucket.com/albums/aa294/oldtiffie/Hydraulics/Hydraulics1.jpg

Won't work, broaches + job require more daylight than the cheap import arbor presses have.
Plus if you use a shop hydraulic press as shown it will take all day to do one keyway, these are tooooooo slow. Proper broaching press runs at roughly 4 to 6 feet per minute.

big job
07-29-2012, 07:45 AM
First off in being a 8 inch put it on casters. Then add another clamp on light. That solves
the seeing issue. Then learn and understand how to use it. I bet 90% think its only
for keyways and making squares, absolutly not true. I dont know everything, but, how
can one broach a keyway in a tapered boat prop without deep pockets. With a shaper
thats a snap. Internal/external splines, dovetails, gears easy. I have made many many
attachments even a die grinder with an end mill. Now its a milling machine. Shapers do
have 3 axis right. Cutting tools dirt cheap maybe a little slow but gets the job done.
I wouldnt mind having a mill maybe bought what you will pay for a shaper and the big
but is the tooling thats the killer. Why I have shaped with common twist drills to ground
down allen wrenches >shapers dont care. So I say its a good investment at a low cost,
I would never sell mine except for a bigger one.

John Stevenson
07-29-2012, 07:56 AM
The OP posted that space is an issue, that's why I queried fitting a slotting head to an existing machine.
This is what i have done and sold a perfectly good vertical slotting machine as basically the machine wasn't earning the space it took.

Slotter's and shapers doing keyways are back breaking machines, slotters are never tall enough and with shapers you are always leaning over, light or no light.

Now at least I still have a slotter takes up hardy any more room than the host machine, doesn't waste space when not in use which is about always and best of all you are working where you can see at a comfortable working hight.

I broach 95% of all keyways as i have invested in broaches but the slotting attachment does the other 5% of blind keyways and weirdo's.

Forrest Addy
07-29-2012, 08:16 AM
A set of Hassey Savage keyway broaches with bushings and a tall Dake arbor press is a middling expense (cheaper than acquiring and equipping a shaper) and it turns a PITA keyway into a 10 minute while-you-wait job. Keyways on a slotter or shaper aint that miserable if you tool up for it and keep organized but if you borrow stuff off the shaper for other work you have to find it and retrieve it.

I worked in the shapers and slotters my early journeyman days. Our section was pretty organized; we pretty much had every thing we beeded in our lockers. If the ship's force came in with a gypsy drum needing a keyway we could cut it in a half hour - but you have to keep organized. As for height we had ond o our 12" P&W slotters up on 12" risers took a giraffe to run it.

Another cool feature about a broach set is if you make bushings with indexing features on them you can cut straight internal splines too - BUT you may have to mod a few broaches.

J Tiers
07-29-2012, 10:27 AM
Agree that broaches and tall press should be about as cheap as a slotter, and work in more places..... you can turn them on their side, but that's harder with a slotter, I'd think (they look heavy, I've never dealt with one).

Disadvantage is blind slots.... the broach needs to run through.

For tapers, if not a blind slot, a bushing custom-made with a taper would allow it.... two if there is no practical way to deal with the shim setup..... seems that a front AND back side shim might be needed, or two tapered bushings. Broach slot might look a bit like a t-slot, or there might be a 'filler" piece.

Ohio Mike
07-29-2012, 11:22 AM
Another cool feature about a broach set is if you make bushings with indexing features on them you can cut straight internal splines too - BUT you may have to mod a few broaches.

Man there is just so much good stuff in that brain of yours Forrest.

John Stevenson
07-29-2012, 11:55 AM
Even better - with pretty pictures.

http://bbs.homeshopmachinist.net/threads/48878-Quick-way-for-cutting-splines

dalee100
07-29-2012, 12:42 PM
Hi,

Forrest, I think hits it pretty well. In a commercial situation, time is money. Broaching is so much faster and therefore so much more profitable that to me it's a not an option.

For the few blind key ways, I would either get a slotter attachment for the mill, which have gotten kind of expensive these days. I just use a boring bar held in a collet and just manually run the quill. But I don't often need to do blind key ways.

dalee

Forrest Addy
07-29-2012, 02:30 PM
One thing not mentioned is pretty expensive but very cool:

http://www.keyseaters.com/stock_custom_keyseating.htm

Dr Stan
07-29-2012, 02:44 PM
If space is that much of a concern just use the lathe to cut keyways. Quicker to set up than a shaper and the only expense is some tooling. BTW, this happens to be the way I was first taught how to cut keyways.

LKeithR
07-29-2012, 10:46 PM
Well, thanks to everyone for the replies. Some interesting ideas--definite food for thought--have emerged. Final decision hasn't been made yet but we're definitely leaning towards the broach and press approach. Truth be told, that was probably the preferred method from the beginning but I did want to explore some options. We do have a press, it's just not optimized for broaching. I'll likely end up ordering a set of broaches--a better press can be a back burner project.

The idea of using a shaper was prompted by the recurring appearance of this nice looking machine on our local Craigslist. It's been appearing periodically for several months now with no takers. I'm still tempted but...

http://vancouver.en.craigslist.ca/pml/tls/3154781121.html

Anyone else interested? It's not far from me and I'd be happy to scout it out if someone had some serious interest.

Someone mentioned a slotter attachment for the mill. Ours is a bridgeport style, fairly large (10 x 50 table, about 2800 lbs. in weight) but I have no idea if there is any kind of slotter available for it. As to need, we've been back in the machining game for a little over a year and have not needed to cut any internal keyways yet. While we had the old shop I don't think we ever did a tapered or blind key so probably not much need there either. In any case, there are numerous other machine shops in the area so if anything really oddball comes up we won't have a problem subbing it out...

Optics Curmudgeon
07-30-2012, 12:42 AM
Bridgeport type "E" head, made for the job. Goes on that odd flat feature on the back of the ram.

dp
07-30-2012, 01:37 AM
I like using my shaper when ever possible. This job was a perfect example given I don't have a press or any broaches.

http://metalworkingathome.com/?p=65

I forgot to take pictures of the gear after cutting the keyway and during, for that matter, but it worked a tread and I finished my thread.

oldtiffie
07-30-2012, 02:24 AM
Hi,

Forrest, I think hits it pretty well. In a commercial situation, time is money. Broaching is so much faster and therefore so much more profitable that to me it's a not an option.

For the few blind key ways, I would either get a slotter attachment for the mill, which have gotten kind of expensive these days. I just use a boring bar held in a collet and just manually run the quill. But I don't often need to do blind key ways.

dalee

The depth of slot can be set as accurately as most other ways on a shaper - it just takes a good bit of care - particularly fro "blind" holes.

The big thing is getting the slotting tool accurately over the centre of the hole to be keyed - but the same applies to any key-way being donoe on any machine.