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laddy
03-01-2008, 01:31 PM
Hey,
How do I machine this??? I have a 6" lathe and a verticle milling machine and am a Newbie. I need a step by step. What to do first, what to do second... Sorry I am self taught and have a dumb teacher! Thanks in advance for the help! Fred I have been screwing around with the photobucket and can't get itto work. It looks like a circle with one square corn=er. Like you drow a circl then do a tanget at 12 and at three and connect. How do I mill the SOB from a round stock Thanks. Soprry my computer skills suck Too. Best to all Fred

IOWOLF
03-01-2008, 01:48 PM
A pic is worth a word or 2, Duh.

No wonder you can't figure it out.

Oldbrock
03-01-2008, 02:02 PM
Let's not get snappy, give the guy a chance. Someone give him a hand posting his pictures. I'm still having computer questions and need help myself often. Peter

rantbot
03-01-2008, 02:08 PM
The description seems clear enough.

A part like that says "rotary table" all over it.

Spin Doctor
03-01-2008, 02:09 PM
As far as posting pictures, well the sticky at the top of the thread list covers that pretty well. For machining an eccentric in the lathe for that you need a four jaw chuck. If you need an 1/8th inch eccentric you need to indicate the part with 1/4" total indicator runout. Or if you have a number of pieces to do then you are getting into the realm of fixturing

BadDog
03-01-2008, 02:13 PM
Yep, seems like a rotary table is the only option with common tools.

And that's a cam, not an eccentric. An eccentric could be created with an offset in a 4 jaw.

ProGunOne
03-01-2008, 02:15 PM
Here's a picture for Laddy:

http://img338.imageshack.us/img338/5334/dsc00351fk4.jpg (http://imageshack.us)

John Stevenson
03-01-2008, 02:45 PM
http://www.stevenson-engineers.co.uk/files/eccentric.jpg

OK,
shape drawn in black at 10" in diameter, I have used this so the figures work out well.
Cutter is 2" diameter, I know it's big but the radius is 1"

So the red path is the path you need to take.

As others have said a rotab is best for this, so find the centre of the circle and we assume start point is 3 o'clock, move out 6.000" in the Y and plunge down.

Move round on the rotab 270 degrees and you will get to 12 o'clock but the drawing will now look like this.

http://www.stevenson-engineers.co.uk/files/eccentric_1.jpg

So now move down in the Y 6" and back alaong in the X 6" and bob's your uncle.

The reason I used 10" should be clear as the dimensions can be scaled to suit.


.

Edit, Ooops it took me that long doing this and grabbing me tea that ProGun and BD beat me to it.

.

A.K. Boomer
03-01-2008, 02:50 PM
U the man SJ,,, Laddy, please try to ignore the only _ _ _ wipe that would rather slam you than help you:rolleyes: Everybody else gets it but he never will, good luck with your part.

SGW
03-01-2008, 02:52 PM
It sure looks "rotary table" to me, too.

Another, pretty tedious way, of doing it would be to work out X-Y coordinates in steps all around the circular part, offset out, say, 1/8", then drill a series of 1/4" dia. holes, spaced far enough apart so there is a small web between each one, then go back and cut out the webs by plunging a center-cutting end mill. Then smooth off the bumps that are left with a file. Tedious....but do-able.

Mcgyver
03-01-2008, 03:11 PM
geez I was halfway through writing up how to make an eccentric complete with pics - there's nothing eccentric about that!

forget the RT, here's the quick way. usually to make the shape you want, the OD is for clearance or aesthetics - ie it doesn't mate with anything. the easiest way to do this is: do the bore. then take a bar, any size, as long as it'll fit through the bore. put the bar through the bore and 'hang' the part between the vice jaws. tighten the vice. bring the cut in and mill down to the OD radius - milling to a scribed line usually suffices. Now, loosen the work, move it slightly, clamp and take another pass. you end up with a series of facets the approximate the outside OD. a quick drag over a smooth file and you're there

here's some examples, one cleaned up and blued and one in the rough - parts for the universal pillar tool

http://i20.photobucket.com/albums/b201/michael0100/upt/columnrests.jpg

laddy
03-01-2008, 03:14 PM
Hey,
Thanks to all (except one) Especially Paul Of progunone. I turned the outside diameter to the corner of the square using my 6" lathe. Then I transferred it to the verticle mill (jig borer ) and am squareing off the corner. Then I will mount it into a rotary tabl to complete the process. Thanks to everybody that helped me. John Stevenson, great help. I hope to return the favor. Fred

BobWarfield
03-01-2008, 03:16 PM
Great help here guys! I really enjoyed reading this thread.

Best,

BW

dp
03-01-2008, 03:20 PM
The next part of the quiz is to figure out the minimum diameter round stock to start with that will produce the part in the size the OP needs. Missing is the actual size needed, unfortunately but he did mention he'd use round stock. It's trivial trig, of course, but part of the fun.

dp
03-01-2008, 03:22 PM
here's some examples, one cleaned up and blued and one in the rough - parts for the universal pillar tool


You have to share how you capped both ends of the dowel pin :)

Mcgyver
03-01-2008, 03:33 PM
You have to share how you capped both ends of the dowel pin :)

each end of the bars are turned down to fit through a hole drilled in the larger dia ends pieces. one side of each cap is count sunk - its slipped on the bar then the end of the bar is peened over into the vacant space made by the counter bore. I'm using a borrowed POS camera (my POS is in for repair but is easier to focus) ....if it was in better focus you'd see the peening marks which i haven't bothered to file smooth yet.

IOWOLF
03-01-2008, 04:09 PM
See Photos do help, Thanx for that .

But i don't see the eccentric part either. :)

John Stevenson
03-01-2008, 04:18 PM
See Photos do help, Thanx for that .

But i don't see the eccentric part either. :)

You need to BE eccentric to see it :D

DP to find stock diameter of this shape multiply the diameter by 1.21

.

JRouche
03-01-2008, 08:59 PM
A pic is worth a word or 2, Duh.

No wonder you can't figure it out.

What kinda crappy answer is that!!! Your one or two liners are freeking old and your constant pissyness like a lil old lady that hates the world is old too.

Why dont you want to help a guy out instead of trying to put him down. Its pretty evident why, you were hammered down through your life and think thats the way people treat each other. Its wrong!! Most people gain more enjoyment boosting folks up than letting them down.

Yer a machinist, you could have helped the guy. You gotta gain some sense of accomplishment from helping people out, dont you??

And yeah, I could have helped him too instead of ranting. But I actually I couldn't, beyond my scope of knowledge. But many with the skills did step up and now Im also a lil smarter. JRouche

A.K. Boomer
03-01-2008, 10:11 PM
JR I stand in awe, my hat is off.

gonna go run off now to rate this thread...

IOWOLF
03-02-2008, 09:05 AM
What kinda crappy answer is that!!! Your one or two liners are freeking old and your constant pissyness like a lil old lady that hates the world is old too.

Why dont you want to help a guy out instead of trying to put him down. Its pretty evident why, you were hammered down through your life and think thats the way people treat each other. Its wrong!! Most people gain more enjoyment boosting folks up than letting them down.

Yer a machinist, you could have helped the guy. You gotta gain some sense of accomplishment from helping people out, dont you??

And yeah, I could have helped him too instead of ranting. But I actually I couldn't, beyond my scope of knowledge. But many with the skills did step up and now Im also a lil smarter. JRouche

His question made little sense to me, Now shut the F**K up and go learn something else like Spell check .

John Stevenson
03-02-2008, 09:10 AM
His question made little sense to me, Now shut the F**K up and go learn something else like Spell check .

And that folks is todays statement from our Iowa representative on Politically correctness, diplomacy and inbreeding.

[ But not necessarily in that order ]

.

IOWOLF
03-02-2008, 09:36 AM
Funny How a Brit should talk about Inbreeding.

A.K. Boomer
03-02-2008, 10:07 AM
And that folks is todays statement from our Iowa representative on Politically correctness, diplomacy and inbreeding.

[ But not necessarily in that order ]

.


LMAO:D


Im just waiting for that golden moment of; Stop it --- stop it all of you, I hate you all -- every one of you -- i hate you I hate you I hate you, then the echoing sound of the almighty exit button, (hopefully for the last time).:rolleyes:
loser...

John Stevenson
03-02-2008, 10:20 AM
Funny How a Brit should talk about Inbreading.
Is that wholemeal, rye or on fish in breadcrumbs ?


In the famous words of someone on this group who will be nameless "go learn something else like Spell check"

.

IOWOLF
03-02-2008, 10:25 AM
LMAO:D


Im just waiting for that golden moment of; Stop it --- stop it all of you, I hate you all -- every one of you -- i hate you I hate you I hate you, then the echoing sound of the almighty exit button, (hopefully for the last time).:rolleyes:
loser...

You will never see that Bummer.

You have tried to get me kicked off here by Crying to Craig over and over. You are just a whiner, a waste of time and skin.
Go eat a lot of silver and be done with it. Looser.

IOWOLF
03-02-2008, 10:28 AM
Is that wholemeal, rye or on fish in breadcrumbs ?


In the famous words of someone on this group who will be nameless "go learn something else like Spell check"

.

It was a Joke, John. Must have hit a Nerve.

A.K. Boomer
03-02-2008, 10:33 AM
You will never see that Bummer.

You have tried to get me kicked off here by Crying to Craig over and over. You are just a whiner, a waste of time and skin.
Go eat a lot of silver and be done with it. Looser.


Just bashed someone for needing spellcheck and he calls me a "looser"

John Stevenson
03-02-2008, 10:34 AM
It was a Joke, John. Must have hit a Nerve.

Aaahh right, must tell the cousins at breakfast in the morning........


.

dockrat
03-02-2008, 01:46 PM
I can feel the love from here :D

JRouche
03-02-2008, 03:38 PM
His question made little sense to me, Now shut the F**K up and go learn something else like Spell check .

LOL Hiding behind the screen again. I'm positive you wouldn't talk to me like that in person.. JRouche

I'm pretty sure you dont talk to ANYONE like that in person.. Dude.. Really.. Is that you one the left!!! Come on.. Tell me you have started going to the gym and laid off the belly bustin sugar cookies since this pic. Too funny.. Ok, Ill do as you say and I will shut the F**K up.. I gotta say, I am pretty damm intimidated by you.. LOL

http://img.photobucket.com/albums/v11/iowolf/SANY0333.jpg

Peter N
03-02-2008, 03:42 PM
I believe that the forum name "Millman II" is available....:D :D

Peter

doctor demo
03-02-2008, 06:22 PM
I did'nt use spell check and I am prepared for any bashing that comes my way. I have a serious question for Wolf, based on observations I've made since finding this site.At times you seem quite knowledgeable and helpfull and at times it seems like you forgot to take your medication. So here is the question ;What kind of prick are you(borrowed from your sig. line) ?


Steve

John Stevenson
03-02-2008, 06:24 PM
Judging from the picture ?

A short one with a red face :D

.

rantbot
03-02-2008, 06:31 PM
and at times it seems like you forgot to take your medication.
Ah well, that is a sore point, isn't it? The unfortunate fact is that the only people interested in machining stuff are old guys, and old guys are always on meds, and much of the time they're on the wrong meds. The only way to deal with it is to apply a good thick layer of "lighten-up."

John Stevenson
03-02-2008, 06:40 PM
Ah well, that is a sore point, isn't it? The unfortunate fact is that the only people interested in machining stuff are old guys, and old guys are always on meds, and much of the time they're on the wrong meds.

How dare you Sir.
One I am not old, Alistair is old, he's old enough for both of us.
Two I am on no meds other than Newcastle Brown Ale in small amounts given the price.

If you insist on this slander I will have to challenge you to a dual with 0-1" micrometers at 6"

.

speedy
03-02-2008, 07:17 PM
If you insist on this slander I will have to challenge you to a dual with 0-1" micrometers at 6".

What?? Two of them? simultaneously??

dp
03-02-2008, 07:42 PM
It was a Joke, John. Must have hit a Nerve.

Why would misspelling inbreeding as "inbreading" be a joke? Inside joke, maybe? You do know you misspelled it, right? Your shift key is still broken.

sconisbee
03-02-2008, 09:14 PM
AThe unfortunate fact is that the only people interested in machining stuff are old guys,

Hey now i aint old! im only 24:D LMAO

rantbot
03-02-2008, 10:02 PM
Hey now i aint old! im only 24
Well, you will be. Just wait and see.

sconisbee
03-02-2008, 10:20 PM
noooo noo! im working on a secret machine thats going to keep me young forever!:D

tattoomike68
03-02-2008, 10:25 PM
LOL Hiding behind the screen again. I'm positive you wouldn't talk to me like that in person.. JRouche

I'm pretty sure you dont talk to ANYONE like that in person.. Dude.. Really.. Is that you one the left!!! Come on.. Tell me you have started going to the gym and laid off the belly bustin sugar cookies since this pic. Too funny.. Ok, Ill do as you say and I will shut the F**K up.. I gotta say, I am pretty damm intimidated by you.. LOL

http://img.photobucket.com/albums/v11/iowolf/SANY0333.jpg

I think IOWOLF is a great guy and a fun person to mess with, hes not a puss so flip him crap when you can. :)

ROFLMAO.

http://i44.photobucket.com/albums/f24/snoopdog6502/iowolf.jpg

A.K. Boomer
03-02-2008, 10:43 PM
Thats one out of shape clown!

Good job with blending in the two pencil necks:)

Who is that guy anyway?:confused:

Its a cruel freekin world out there sometimes, esp. if you never get the message...

oldtiffie
03-02-2008, 11:11 PM
and at times it seems like you forgot to take your medication.


Ah well, that is a sore point, isn't it? The unfortunate fact is that the only people interested in machining stuff are old guys, and old guys are always on meds, and much of the time they're on the wrong meds. The only way to deal with it is to apply a good thick layer of "lighten-up."

Odd that.

I don't know about the rest of the world but "Meds" is a brand of tampon here in OZ.

So the thought of anyone taking or having to take meds is -shall we say? - "interesting" - especially if prescribed the
larger sizes.

Nah, them that some might have thought needed them are too old like a dried prune and the biggest wouldn't fit. Or perhaps getting them in is one thing - keeping them in might well be another.

Interesting definitions of "meds" here too.
http://www.urbandictionary.com/define.php?term=meds

Me? Old? Not really - I'm only 71.

ProGunOne
03-09-2008, 06:53 PM
Here's the finished part posted for Laddy:
http://img166.imageshack.us/img166/234/laddydsc0003od2.jpg (http://imageshack.us)