They are turning out great now - mostly had to back WAAAAY down from my usual aluminum speeds and feeds. Using the highfeed option and going into the corners very slow was another important piece. Drilling the hole in the corners works well too - I drilled them about .005 under size. As I mentioned earlier, I am getting better than a 16u finish now - with no measureable taper (measureable that is with what equipment I have and certainly well within +/- .0005). Thanks for all the help! Now... Who is stopping by for a beer?

Right you are, Jack! Better than a 16u finish and bang on for size as best I can measure it. Looks nearly polished. I had to put a couple of M0's in to clear chips, but other than that, working great. The highfeed with finish only worked great for entering and exiting the corners at a much lower feedrate - no singing at all!!! Thanks! I usually drink wine myself - but I know where to come up with a couple of six-packs of your favorite!

Just noticed - my post count is stuck at 456.... Does that always happen when you start the thread???? wait - they incremented. - sorry - case of "D'OH" here...... getting late I think....

Thanks! I now go forth to grapple with this aluminum brick once more!!! At least I have lots of stock for a change. Now if I only had a chip conveyor.........

BC - I do have a nice 1/4 dia two flute high-helix extended reach (a Javelin I think) that is doing a good job for me in the R.125 ares - unfortunately it isn't long enough to get all the way down....

darn.... I sort of got hung out to dry on this one - Must be done by Monday and my only other choices are a 1/2 dia 3-flute and a 1/2 dia 4-flute that are long enough to reach. I do have a 7/16 dia 3-flute serrated edge rougher - but somehow I don;t think that one will work too well for a good finish... Would ramping down the walls be better than a standard 2-pass contour (or more passes to take out the spring) at a slow feed/low rpm? The only problem with the ramp is dying of old age before it finishes..........

Thanks Jack. I am currently running the 4-flute 7/16 dia at about 1000 RPM with a feed of of about 12 ipm. So I should drop this to about 750 RPM and about 9 ipm??

I am about to loose all my hair on this one..... I have an aluminum box to make - 3 inches wide, 5 inches long and 2-1/2 inches deep. The walls - before roughing out the exterior - are about 1/2 inch thick. The corner radii are R.250 for the full depth of the box then the first 1.17 inches are relieved to a radii of R.125. I am getting the material roughed out just fine - leaving about .030 on the side walls to clean up (and R.750 in the corners) using a 2-inch shell mill to blow the chips out. I have been using a long reach, releaved shank 1/2 dia four flute to finish roughing the interior to about .002 of material left for finish. The problem that I am having is finishing the interior - particularly the corners. I have tried ramping in with a 7/16 dia four-flute (3 inches of cut). I have tried a straight contour. I even tried a 3/8 Dia extra length in the corners. Basically the side wall finish sucks and the corners are worse. I haven't had a lot of experience with deep sidewalls like this. I thinking of clearing the corners with a 1/2 dia drill first..... Any ideas?? EDM (I wish) is not an option.....

Welcome aboard!!

The exact temperature is not the real problem. The real problem is maintaining a steady-state temperature at the machine in order to hold a tolerance. On a +/- 0.0002 part, a couple of degrees of temperature swing will cause you to make scrap. I can hold +/- 0.0005 with my Fadal all day long - but ONLY if the room temp is fairly constant (+/- a degree F). Start moving the room temp more than that and I will be chasing the part size the whole time. Of course I don't have Cool Power on the spindle, or glass scales, so temperature has a fairly dramatic affect on my machine (a 10 degree F change can move my Z by up to 0.0015) - it will affect a compensated machine less - but it will still affect it.

Yep - I keep getting prints from a manufacturer back east with 4 decimal place callouts, features that are darn near impossible to make, and loooooooooong holes with back-counterbores (and a little itteey bitteeey window to reach in through to put on a back-counterbore twist-lock head). I talked to their chief engineer and asked what the heck was this stuff. You really want to pay for that kind of tolerance and features? He said that the engineer was a helicopter designer. Never liked helos before - now I will be doggoned if I will get in one if this is the sort of engineering that went into it......

Woodshapes, if you have the image scanned - it needs to be one of these file formats: *.bmp, * tif, *.jpg, *.pcd, *.pcx, or *.gif. Then, in Mastercam, go "File", "Converters", "Next menu", "Rast2vec", find your file name and open it. You will then be at a conversion screen. At this screen, you can use black and white or colors to "filter" the picture for the best conversion - you may have to play with it a bit. When you have a pretty good picture in the right pane - hit "ok". Follow the directions and you will have Mastercam lines and arcs.

And... the only silly question is the one you didn't ask, but should have. By the way - good question - I didn't even know that there COULD be a different splash screen!

Works for me! I can't seem to get away from it at work or at home (my in-laws are liberal Democrats and we are dyed-in-the-wool Republicans).

+1 on never using the Windows nVidea drivers. They are 6 months behind the latest release from nVidea AND it is not the same driver as the "same" version that was available from nVidia. Looks like it was "stripped". What is odd is that the driver from nVidia is "certified".

+1 to James. The amount of force applied is dependant on #1 the amount of vacuum you can pull (21 to 24 inches of Hg is pretty good - 27 inches and up is considered "high" to "hard" vacuum), #2 the local pressure (which DOES vary from day to day as well as being dependant on your altitude), and #3 the surface area. Using the figures quoted by James provides a reasonable approximation of what you can expect for holding force. Note that the quoted value is at sea level at standard pressure. quote: 1" of Mercury = .49112 PSI By definition, a pressure that is less than the standard pressure at sea level is considered a vacuum. No wonder it sometimes sucks to live at 6300 feet.....

I actually used photoshop to turn the image into pure black/white, cleaned up the image a bit, then used the Mastercam Raster-to-Vector converter and set the smoothing up a bit higher than default. Looks like I can't kill it either.....

DavidB The converted IMG_0794.MC9 file is back in the same place as the picture file was on the FTP site. When you grab it (and are sure you have it) go ahead and delete both from the site. The Yellow outer arc is my best guess of where to place the edge relative to the artwork - it seems about right, but the circular edge was just a little too muddy to capture well due to the angle of camera to the badge. However, the art came out nicely. If you run a copy (or print onto a vellum) and compare it to the original and discover that it is "stretched" in one direction due to the camera angle, try playing with "scaling" the red lines portion in one direction to "unstretch" and correct it. I have sometimes found that necessary if the picture was not dead on perpendicular to the object being photographed. Enjoy!

I grabbed the file and will be looking it over this evening. Cheers

I am CERTAINLY not counting on ANYTHING from Social Security. I get my annual statement from them and would not have a PRAYER of living on what I will get back. Like you, I wish I had the FICA money back to privately invest.....I would really have something then.

quote: quote: -------------------------------------------------------------------------------- Stock keeps moving -------------------------------------------------------------------------------- The last time that happened to me, the vise wasn't tight on the table My bad - My first thought also.

If you take the kerosene and cut it about 50/50 with a high sulfur content oil - the old boys used to use that for cutting steel. Smoky, but it works. Probably carcenogenic as heck too.....

The other "sure-fire" way to get retirement growth is to absolutely take advantage of any company matching that is available to you. For example, the company I work for during the day has a 4% matching policy (they will match 100% of my investment up to 4% of my salary). That means that I AUTOMATICALLY make 100% on up to 4% of my base salary. If I put in $100 - they put in $100 - I get the interest/investment growth on the $200 AND the $200. I don't put in more than they match, because there are better investments for anything over what they match. What I find scary are the statistics on how many folks will be dead broke (or worse) when they reach retirement age.

A little "smelly" too - but it does pretty much stay put while machining. However, I prefer the Monroe Fluids Cool-Tool II - it smells MUCH nicer and works even better than kerosene. The "spec" sheet is here: http://www.chess.cornell.edu/Safety/MSDS/cool_tool_II.htm

DaveB, a good pic will probably work just fine. Probably don't need a scan unless you can find the badge in a book or similar publication. The more important part would be the actual dimensions (height and width would be the minumum needed) to properly scale it. When you take the picture of the badge, try to get the camera perpendicular to the surface of the badge with lighting coming in over your shoulder - or at an angle to the badge. Get as crisp a shot as you can - as close up as you can. Try not to use a flash - it will "wash out" the picture and might even result in a lot of glare on the badge. That will help to make a nice "clear" set of lines and arcs for the artwork.