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Slitting SS pipe

What about feed and speed? I have cut a lot of SS for this company, actually I cut more SS than any other metal! But I have never cut this many small slits in SS or to be honest any other material though I might have a few very thin saws. Not sure where I got 150rpm but recalculating I'm thinking 70rpn. Have to see what speeds are available on my mill.
Well, I'd setup with one saw and make a few test cuts....only risking one blade.
1 or 10 will make no difference to the mill
Using the large spacer will help.
Lock all the other axis and make sue the table gibs are not sloppy..
Should be easy once you're setup.
what is the size and tooth count again??
May be advisable to call the Manuf of the saw and get their opinion.....probably where I would start
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Tooth count is 72 on 2-3/4" diameter from McMaster. Company ordered 10, of the .014" and 10 of the .016" probably because additional 22 of the .014" are back ordered to Nov. 13. My request was to get addition 2 cutters for test purpose.
Not sure if I can get speed/feed info from McMaster. However I did call them, they will try to e-mail me the info.
What about clamping the pipe, I sure pipe in not very round! 7/8" X 3' steel bar is on the way to make jaws.
Just to be clear on this your part length is somewhere between 18-20”?
Three rows of slits in pvc pipe and the part breaks at the top or first slit as you mentioned.
Are the three rows of slits at the same distance from one end, in other words are they all aligned radially? Did your customer try pvc with staggered slits? Not much material left if the slits all line up.
PVC is easy to work with and it sounds like there has to be some other solution to prevent breakage. Perhaps a manifold at the bottom to connect all the pipes? There must be some kind of agitation in the tank causing the breakage so I am thinking there must be a way to support the tubes? How long do they last before they break?
Your asking questions I have no answer for. I do not know anything about the machine. I did work there as an Engineer but retired 10 years ago. But have a small machine shop and do work for them that no other shop can do. Or should I say dummies can't do! Total length of the pipe including 3/4 NPT thread on the ens is 17-5/8", 3 rows of slits at 120° and they are inline as best as can be. First slit is 1-3/8" from threaded end. I recomputed space between slots and it's dam near 3/16" (82 slots in 15.64")
As I have said before I'm sure they tried other ways to support the tubes! When I asked about support they said gravel of some sort is filled around the tubes so they are well supported.
This is an attempt to make the tubes stronger. Pipe will be delivered tomorrow, cutters and tooling too. What I need is help making the part they want!
McMaster sent info for cutting speed and feed, Also a chart. I called the company and asked about dept of cut, I was surprised they said take full depth of cut that should be about 1/8". Actual cut depth from top of pipe to where it will result in 5/16" opening length into the ID of the pipe is .144". SS likes to work harden and pipe is soft so I'll give it a test drive. Recommended cuter speed is 35 to 70 SFM for hard SS and 70 to 105 SFM for free machining SS. Feed rate recommended .003 to .005 FPT.
Good luck with this project. Stainless is annoying on the mill. Hopefully those feeds and speeds will give good tool life with so many slots to make, nearly 8000!
With ten cutters on the arbour that will still be 800 passes assuming one pipe in the vise. My #2 KT had only 8 or ten inches of travel in Y so you will have to move the part in the vise at least once or twice? Cut your passes in half if you can fit 20 cutters, cut in half again if you can fixture for two pipes.
The good news is that the pipes are just a filter so the slot locations should not be critical.
I will have 10 of the .014" cutters, If I spaced them 8 of them 10 slits apart I will only have to move the table 1.9", that will give me 80 slots. I can add the last 2 later or maybe the company will drop the last 2 near the 3/4 NPT threaded end where breakage is happening. When I talked to the guy at the cutter company he will get the others on back order out ASAP so I will have 32 of the .014" cutters. Since my customer would like .014" slots we can return the .016" for .014" they ordered because more than 10 were not available. That will increase the total .014" cutters to 42.
10 cutters moved
As I have mentioned, I know little of the application. It was not there when I was. Simply put they have seemed to decide upon a solution and handed me the job to make it so. There seems to be a number of companies making "well pumps" since the guy I talked to at the slitting saw manufacture knew exactly what I was doing and used the term "well pump". He said they use PVC, I guess no one makes them from SS! Probably too expensive so they dumped it on me! Not sure if they are using it as a well pump!
Now I'm trying to determine the best way to hold the pipe! I know it's not perfectly round nor straight!
Not worried about location error, slits as per the cutter maker are to stop sand. Location +/- .015" and probably more will be OK! I don't want the pipe to move and destroy the cutters. I do plan to drill holes at the end of the pipe as locator for 120° plus pin in holder to stop any rotation of the pipe. Later cut the end with holes off. I do have a set of matched mill vises, one solid jaw in the 2 vises on the non movable side and split the jaw so 1/2 of the length is in each movable side.