Messages

481

General Mach Discussion / Re: Questions 1st Aluminum Cut Sample

« on: November 12, 2012, 09:19:59 PM »

Thank you RICH

482

General Mach Discussion / Re: Questions 1st Aluminum Cut Sample

« on: November 12, 2012, 12:56:00 PM »

I attach 2 pic to show my V engraving end mill + the control panel layout which I want to cut / engrave (this panel is presently made out of plywood to get the machine going).

For cutting the openings I plan to use now a 2 flute center cut end mill at 2500RPM and 7" to 10" / min feed rate

For the engraving I will use the same 1/16" V engraving end mill at same as above RPM / feed rate.

I read in another forum that to much RPM / feed rate develops too much heat and causes the aluminum to "bubble" upwards. Now I don’t know if the RPM / feed rate I said above are ideal but it will be a start point.

483

General Mach Discussion / Re: Questions 1st Aluminum Cut Sample

« on: November 12, 2012, 08:15:37 AM »

The V tool I use is a 1/16" engraving 60 degrees end mill and cuts on both sides of the "V". I know that I have to play with the feed rate and RPM to get a good cut on Aluminum and hopefully I will get there sometimes this week

484

General Mach Discussion / Re: Questions 1st Aluminum Cut Sample

« on: November 12, 2012, 12:51:38 AM »

Yes the"bike part" post is pretty good, if I can do something close to it I will be very happy, lol

I do have a 2 flute center cutting end mill and will give it a try soon to cut the 2"x2" square. For the engraving I will use again the 1/16" V end mill I have but reduce the RPM perhaps to 2K to 3K and the feed rate down to 15

485

General Mach Discussion / Re: Questions 1st Aluminum Cut Sample

« on: November 11, 2012, 10:41:24 PM »

I used MastercamX5 but remember I have no too much experience. I don’t want to use Lead-in because the samples I do now are to eventually help me cut the openings / letters for my control panel (8.5"x21"x1/8") and I don’t have a space for Lead-in.

Yes I also see the chatter marks and I think it's because of the wrong type end mill I use. This is the 1st time I do a cut in aluminum and next time I will try a 2 flute end mill as you suggested

486

General Mach Discussion / Re: Questions 1st Aluminum Cut Sample

« on: November 11, 2012, 09:16:01 PM »

Hey Fastest1, thanks for the comments

No experience here, I just used a drill point end mill because I thought it will be the best to straight plunge into aluminum and yes you are right on the MDF I used a 2 flute center cutting endmill.

The intent was to cut thru the square and I didn’t calculate any parameters, I just used what I have gathered from others on the web.

I don’t understand what you mean by "Also don't expect the letters to turn out very well unless it is engraved". I did use a 60deg V bit and although the letters turned out good, I was expecting better.

Also I don’t understand what you mean by "I would have done a circular or helical ramp into the inside of the line"

487

General Mach Discussion / Questions 1st Aluminum Cut Sample

« on: November 11, 2012, 05:03:02 PM »

Finally I cut my 1st Aluminum sample and have some questions. The sample is on a piece 5.5”x4”x1/8” thick and the square I cut on it is 2”x2”. Before this cut I did another sample on MDF and all the cuts on MDF look good (see attached pic)

1. The tool I use for the square cut is 1/4" Drill Point 2 Flute Endmill and the start of the cut is at the top left corner. The speed of the tool is about 6000RPM and the feed rate is 20"/min. As you can see on the attached pic. the cut at the start is not the same as the rest, its deeper and wider. What may cause this?

2. I was expecting the cut to be more sharp and clean but have no experience with Aluminum cuts so is this normal? Perhaps I use the wrong bit?

2.  The thickness of the aluminum is 1/8" and I did the square cut with 2 passes of 1/16" each pass but the tool did not go thru. What is wrong here? I set the depth with a zero touch plate so I know that the Z is set properly at 0 on top of the material

3. This is not a question about the cut but I guess the pump I have for the cooling liquid is not big enough to pump the thin oil I use. I control the pump with a momentary switch and when I press the switch the oil just trickles out of the nozzle. Can you recommend a better pump? 

488

General Mach Discussion / Re: Status Line Message and DRO Readings

« on: October 28, 2012, 01:33:51 PM »

Good to know Gerry, thanks

489

General Mach Discussion / Status Line Message and DRO Readings

« on: October 28, 2012, 12:22:37 PM »

Perhaps this message on the status line was there before and never notice it but I just loaded a new gcode and the status line says: “Min –Z -.0625”. I know that .0625” is my depth of cut but does this message indicates something else that I should be aware?

Also I set my piece to be cut in the center of the table, bring the tool to where I want to start my cut, zero the DRO but the DRO indicate:
X -0.0000, Y +0.0000, Z -0.0000, A +0.0000
Why some are minus and some plus? Something I'm doing wrong?

490

LazyCam (Beta) / Re: No Entities Shown

« on: October 19, 2012, 09:07:59 AM »

Very interesting RICH and I will give it a try, thanks