[CNC] Question On 1045 Steel Cnc Cut Run. Looking For Advice.

[countryguy]

Hi everyone, Looking to dialog some about the recent project w/ my Son. We moved on from his Axe project and onto a full Katana sword. These are all about learning... basically our "hello world" first jobs. all feedback welcome.

First axe: My experience w/ 1045 in the past was that we had a heck of a time with it!! For the Axe project we took to Annealing the 1045 which made it so soft you could bend it (1/4 HR plate) over your knee. Thus cutting it was a breeze! Clean crisp cuts. (pics below).

This time: Making a Katana sword- Our first long object! We wanted to see if we could be like the big-boys and just take 1045 and run a CNC program upon it. With an Anneal process we run the risk of warping and honestly, we just felt we should be able to mill this stuff on a beefy 30taper Supermax YMC setup??
The real sword will be out of 1090/1095... So that is why the setup Q's here.
Here are the details. (pics below).
- Cutter- 5/8 HSS-Cobalt, Running .125 stepover, and 0 to .09 DOC on a slope cut. (see pics). This run is cutting down the blade.
-RPM SFM was experimented with G-wizard pushing the original values and range. RPM 400-500RPM. SFM 2.5 to 5.0 (3.34 per wizard). clockwise rotation. Only cuts on the down slope run. (see pics).
-Overall, the cutter wear became excessive on the bottom. To much rubbing. Corners are OK and it even feels fairly sharp on the edge. Towards the end of the long run, it would chatter rather hard at full DOC.
- The pic below shows it is chewed and a really ugly cut compared to the axe we did. (annlealed).

What I am wondering- I'm considering just going back to just Annealing the swords. It's a way to save cutters, and speed thru the job.... But- It just seemed that we should be able to cut this 1045 w/o a lot of issues and fuss every time.

My own thoughts:
-Should I omit the rubbing down force cutting from the Z0 top point to the .09 DOC. (called a merge job in DolphinCAM.) Wondering if I should start on the .09 DOC off the far edge and cut up to the 0 point??
- Go to conventional -vs- Climb?
-Carbide in the past just breaks unless the work is super super rigid for my newbie experience.
- Or just put the 1045 on 1095 into the oven and run the Anneals.
- Am I taking to thin a cut? Should I up the stepover? or run this in 2 passes (at a total of 2.5 hours).
- Maybe I should be trying a Carbide these days?
Some pics:







Thanks everyone. HAPPY 4th!
Jeff and Mitch.

 

[JimDawson]

I think for something like that I would make a MDF fixture to support the blank at the correct angle. Then clamp the blank in enough places to anchor it securely to the fixture. Maybe with toggle clamps? This should minimize any chatter. Then for the other side, create the mirror profile including the area for the first machined cutting edge.

If the cutting edge is getting dull, that might be an indication of spindle speed too high. I would cut that back by about half and see what happens. Keep the feed rate up to force it to cut rather than rub.

Maybe this will help.
.

 

[countryguy]

Thanks Jim.... I too agree with your assessment of putting the Blade at an Angle. We did the math on this and had a 6.17 angle to put the taper and depth correct for a simple 'area clear' in dolphinCAM. The son got a lesson in why you need Trig in life. LOL. When we clamped it all down the thing warped and skewed. Its nearly 30" long. So our cut was shallow here and deeper there. We also realized we would need to drill and tap holes for some custom workholding as the regular hod-downs just get in the way. Lots of little issues that just take time. Anyway, as soon as I grab a piece of 1/2" or thicker steel plate from ALRO I'm going to try that method again. Good to know we were thinking along the right lines anyway.

Some may be thinking- Why not just run it on the belt sander/grinder like everyone else... We are. This is just trying to learn a new technique. Labor and dust and sweat go w/ the Artisian way. Trying to play and learn more than anything else.
Enjoy the day all.

 

[JimDawson]

The son got a lesson in why you need Trig in life.

That may be the most important part of this whole experiment.

 

[countryguy]

Thought I would put up a few thoughts on what I'm trying next- I now have a huge 3/4" by 12" x 35" plate I barted some services for. (heavy sucker). will setup to the proper angle for an area clear per Jims comments above. Now, I'm waffling on the end-mill to use. Carbide or Cobalt. I have an annealed 1045 blank and a non-annealed 1045 blank. Phase II is a 1090+ blank. Maybe even an alloy of M2 or something fun if we get this into a "zone" of costs per sword for the Son.

Where I'm waffling a bit today- Since we are considering hard stuff and exotics- Should I also experiment w/ an indexable end-mill? I see mixed results. They have a purpose and a place it seems. Solid performance when dialed in right. I'm starting to consider that I may be on their list? a lot cheaper to pop in $10-15$ inserts per item rather than making scrap of my good end mills. I also realize that I'm a total novice on getting Feed and Speeds dialed in w/ my 30 taper. I need to bite the bullet and do some experimenting. I have been on a NY-CNC vids kick lately. There is some really good work he did w/ his Tormach 1100 and woc/doc values w/ carbides from lakeshore. My thinks it's overdue on my end. Again, would possibly rather do this experimenting w/ an indexable. Just some thoughts on a quiet Saturday.