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Planing Straight Edge Set Up

Richard King

Diamond
Joined
Jul 12, 2005
Location
Cottage Grove, MN 55016
I figured I should start a new thread so I don't get accused of Hi-Jacking the Feather-lite thread where I was going to write this. I want to make sure everyone knows I am writing so "all" can learn while we are discussing planning now.

I used to have a Cleveland Openside and I would first set up the straight-edge the same way pretty much but on the edge of the table so I could feed down past the flat and not have to worry about gouging into the table. Plus on a thread where I showed the readers that you machine the side of the casting first because some planers like Stephen Thomas planer was worn on the ends when you stand up the SE you won't get it flat as the planner table will rise up on ends, but planning on the side the rise doesn't matter. (still looking for that thread when I taught Stephen that)


Here is a great group of photo's. Note this can be done with all brands of SE's and parts needing planning.

48 inch straight edge planing

That is found in this old thread:

https://www.practicalmachinist.com/...law-straight-edge-my-way-doing-anyway-326602/

I would also use a flat tool with a small radius on the leading edge not a round cutter. Look at last picture on post 3. https://www.practicalmachinist.com/...laning-straight-edge-287285/?highlight=Planer and the pictures in the dropbox pictures. The large radius tool I believe pushes away as it cuts and the flat pulls in as it cuts.

I used to sometimes mount Kurt Vise on top of table too and grab SE on back flat side so I didn't introduce twist in by clamping. Other times I would put the dovetail side into the table T slot and plane the flat back side first so I would start the 2nd cuts using a know flat surface. I am sure others use other ways. I am just pointing out different strokes for different folks. Rich
 
Nice pics and set up, Richard.

I've done a few now by clamping to angle plates on a 26" stroke shaper. Not as elegant as a planer and limited for length, but got the job done and needed minimal scraping for flat.

You still have that little HBM in the background of one of the pics?

L7
 
The drop box pictures were taken by Warrens friend out in New Hampshire. I sold my machines for the most part to A&D Machine Rebuilding in Roberts WI. I wish I had the planner now though.
 
i often mill to <.0004" per 60" flatness but many times it requires many rechucks to let part warp and mill out the warpage. not unusual to have to take 3 or 4 .0005" cuts when trying for less than .0003"
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sometimes there are limits to high feeds and speeds if tolerances are tight, basically have to slow down often on tighter tolerance parts. and sometimes rechucks part is basically finger tight as it can easily distort when tightened
 
Tom ..lol...show everyone that Giant you run :-) When your running a CNC mill with a 20' table 36" or 48" should be with-in .0005" most of the time. I like the info on loosening and tightening the clamps. Tom what's your opinion of "Ringing" or hitting parts that are hung on a rope or strap with a soft blow hammer or 2 x 4 to vibrate stress relieve during machining. If you would, could you ask the scrapers at Gleason and see if they have done this technique?
 

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Tom ..lol...show everyone that Giant you run :-) When your running a CNC mill with a 20' table 36" or 48" should be with-in .0005" most of the time. I like the info on loosening and tightening the clamps. Tom what's your opinion of "Ringing" or hitting parts that are hung on a rope or strap with a soft blow hammer or 2 x 4 to vibrate stress relieve during machining. If you would, could you ask the scrapers at Gleason and see if they have done this technique?

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i have never seen scraping done but do know its done for oil retention purposes on already machined surfaces. many older parts in for rebuilding i can see spots where scraping marks are worn off. i often machine .002" to clean it off and it gets rescraped.
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warpage some parts are vibration stress relieved. other times warpage is from the part clamping, temperature effects from machining (cold coolant can be a problem) often why parts change distortion after hours or days from the temperature stabilizing, gravity causing part distortion from a parts weight and how held or clamped. cutter pressure can push part and cause a spring distortion.
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some parts have hardness variations and machined waviness can be indicated in sync to metal color difference seen in the metal indicating variations in metal hardness.
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just saying i often end up taking many .0005" cuts with lightly clamped parts until they indicate ok. some parts can be stubborn trying for a .0003" tolerance. and of course as machine warms up the tool cutting edge can be easily .0005 lower as the machine and tool warms up. often the many extra passes is to "warm up" and stabilize the machine too. you literally can machine a big circle or rectangle and get a lap difference where cutter started and where cutter ended meet
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i also often have seen move machine in handle mode with .00005" indicator and stop as see the way oil between the slide sections flow away and or take 10 to 20 seconds to stop moving the last .0003" as the oil moves slowly. obviously if aligning a part to .0001" you have to be patient
 
Apologies for not contributing (yet), but I have a couple of major deadlines at work and have to catch-up with everything I left behind last week.
Anyhow, the thread Richard is referring to is this one. As soon as I have a few minutes (hopefully before the end of this week) I will post much more material (photographic and video) documenting the work.

I find the information in this thread extremely useful and had already a couple of "doh!" moments reading the posts and studying the pictures.
The major challenge I find working at the Museum is that I plan for something 100 miles away from the machines and get there to set up for a job having fossilized thoughts that blind me from the obvious.

That's everything for now. Back to work.

Paolo
 








 
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