How do I mill aluminimum and bronze?

[Levi Chanowitz]

How do I mill aluminimum and bronze?

I am an engraver. I have 4 engraving machines and a laser.

I am looking to mill 1/4" bronze and aluminum plaques. Those with the letters protruding around.050

How would I do it?
Can I use my present engravers?
What type of cutters would I use?
how long sould it take to mill a 2" x 10" with 3 lines of text that are between .5" and .25"
Can it be cost effective?

[Kenneth Hertzog]

Levi
You didn't memtion the type of engravers you are using.
If you are using a milling machine and you have a cad program then reverse engraving is what you want,
leave the letter and remove the excess. As for time It should go fairly quick since it could be done in one pass.
Hope this helps
ken

[Levi Chanowitz]

I have a dahlgren systems 1, a newing hall, a meistergram-h-square and a small rolland.

Are these good enough?
Ho are these different than a cnc?
What cutters do I need.

I am doing a 2" x 9" with 3 lines of text, .25" -.5" letters

[Kenneth Hertzog]

Levi
are any of these machines computer controlled?
Will they let you reverse engrave?
CNC is Computer Numeric Control
If you have a CAD program you can enter the text
you want and then remove the outside and leave the letters.
It takes some work but its worth it.
will try and answer any questions you have.
ken

[George D Gabert]

I think the roland comes with 3d relief software built in.

[Levi Chanowitz]

I can get the software to engrave the reverse.
My question is: is my machine going to be time and cost efficient?
Will it do a good job?
What cutters do I use?

[Kenneth Hertzog]

If I were doing this job on my machine
I would use a flat milling bit.
that may be in your case .125 ( 1/8 )
take a piece of scrap and do a little engraving
if it seem slow and the machine is not laboring
speed it up a little and try again
then estimate your time and give it a shot
you will quick learn if you want to do more :rolleyes:
sorry I can't be of more help
ken

[Scott Shepherd]

Levi, I don't own any of the machines mentioned, but I do know there are people who do that stuff for a living and I believe it's more economical to have companies that specialize in it do it.

I believe they do a lot of it via chemical etching. The problem with milling it all is you'll have tool marks. So once that's done, you'll either hand to sand out all the cutter marks or use some paint that covers it well enough to hide the cutter marks.

I think the people who do it well do it cheap enough that it's not worth trying to do that way.

Just my opinion.

[Levi Chanowitz]

I was planning to paint it. I have a niche market for it only if I keep my costs down. I need to find the most economical process.
If they can do it, why cant I?

[Kenneth Hertzog]

Levi
I agree
you have nothing to lose but some time and a little effort.
nothing ventured nothing gained
please let us know how things come out.
ken

[Richard Rumancik]

I was planning to paint it. I have a niche market for it only if I keep my costs down. I need to find the most economical process.
If they can do it, why cant I?

Levi, I have been investigating the viability of this as well. Acid etching and casting both have their pros and cons; however, I don't know if anyone can say off hand that machining will work for you or not as it depends on a lot of factors. Your costs will depend a lot on your setup, software, equipment, etc.

Some people carve into brass like a deep engrave (recessed characters). Removing the background (creating raised characters) is more difficult but simulates a casting better. Have you looked at V-carve by Vectric? That is what I will use if I pursue this. The cutters are usually 45 degree or 60 degree (although you can use endmills). But a slope looks good and similates a casting better.

With V-carve, you could actually apply a texture to the background similar to the way a cast plaque is textured. Then you could paint or lacquer the background. No need to clean up cutter marks and it hides imperfections. It might be easier to paint the whole thing and then sand off a thou from the raised letters to polish them up. (Would give the look of a cast plaque). Or maybe there is some way of masking the brass, machining, painting, and then stripping the mask. (Pressure washer? Warm air?) You might be able to come up with a system that is competitive with alternatives out there. (That's what I am hoping for.)

I think it is worth looking at. You might also consider using Corian for some items. Check out the Vectric site if you haven't already.

[Levi Chanowitz]

"V-carve by Vectric" Are you suggesting that I use my own equiptment with their program?

[Richard Rumancik]

Levi, I don't know much about the equipment that you have. If it is a proprietary interface then no, you couldn't use V-carve. You need to be able to send g-code from V-carve to the machine. If your current equipment can't take g-code I'm not sure what options exist and what your budget is. You might try to find out if any "translators" exist to convert to the "native" language of your machines.

The Roland might be the best bet if it is big enough. Did a quick check and found this comment:

"For industrial users or for those wishing to progress to more advanced machining, the Roland range of machines are G code compliant and are therefore able to be used with industry leading computer aided manufacturing (CAM) software such as Mastercam, Surfcam, CAMWorks, VisualMill and Machining Strategist among many others."

Find out about the Roland you have. If it was sold with a design program maybe the g-code has been hidden from you in the background. You may be able to use V-carve (g-code) with it.

In some cases an older machine can be upgraded by removing the older "controller" and installing a PC-type interface. If the hardware is otherwise in good shape it might be viable. Solustan used to offer a mod to older systems but they seem to call these "legacy" products. Not sure what their new products do.

Or you could hack an older system and install a FlashCut front end. It would take some electronics know-how. If your steppers and motor drivers are good the FlashCut controller would cost about $1500 I think. So in this case it would be V-carve ->FlashCut -> machine. (You could also import Corel files or other vector files into V-carve.)

If any of this is unclear please ask . . .

[Levi Chanowitz]

Why would i need V-Carve? my software could probobly handle that now.
Can my engraver machine metal?

[Richard Rumancik]

You know your machines better than I do. Sorry, I can't tell you if your machines can cut brass or what cutter to use. Maybe talk to the manufacturers or your reps for advice as to the machines' capabilities.

V-carve was only a suggestion as it has the capability of simulating a casting better. But if vertical walls are acceptable then you can use other software.

[Roy Shaw]

Levi
are any of these machines computer controlled?
Will they let you reverse engrave?
CNC is Computer Numeric Control
If you have a CAD program you can enter the text
you want and then remove the outside and leave the letters.
It takes some work but its worth it.
will try and answer any questions you have.
ken

I want to make some clock faces like these:

http://www.crafthome.com/subsidiarypages/clocks/jm/copperclockMainFramePage.htm

That was etched, but can a CNC mill do that? What is the spin-up time on a CNC mill, i.e., how long would you guess it would take from receipt of the machine until I could attempt something like the clock face?

Thanks.

Roy Shaw

[Kenneth Hertzog]

Roy
that is a really tough question.
are you wanting to leave the numbers raised or are you wanting to
mill out the numbers and design.
The learning curve is the CAD program and getting the results you want
then picking the material you want the face made from.
Also you must hold the the material firm on the bed of the machine so back and forth cutting doesn't move the piece.
If I didn't answer the question correctly I'm sorry and will try again.
ken

[Roy Shaw]

Thanks, Ken.
I want to make them out of 1/8" copper sheet and mill away about 1/16" everywhere except the numbers.

Reading these threads and searching on the various manufacturers, it looks like one of these benchtop mills will cost about $3000, excluding the computer. Is that what you would say too?

Thanks for the help.

Roy

[Kenneth Hertzog]

Roy
You are close on the cost of the Mill with CNC setup. You are right also on the computer, you will need one but don't forget the programing to do your drawings and such, the cheap programs can't do some of the things the better ones can.
ken

[Levi Chanowitz]

You need to figure how much time it will take. Will it take 5 minutes or 5 hours?

[Kenneth Hertzog]

The program that runs my CNC equipment, when it loads up the G code it also tells you how long it will take to run. If this time is not acceptable you can change either speed or other parameters to make better time and reload the program. Its usually not off more than a second or two.
ken

[Frank Triana]

Each type of material has a constant related to the type of cutter composition (high speed steel, cobalt, carbide). There is a speeds and feeds chart/formula out there some where. Google it. The diameter of the cutter, what kind of cutter (high speed steel, cobalt, carbide), and material determine the RPM you can go. Too fast and you ruin the cutter. The feed (how fast) is determined by flutes, depth of cut, horse power of the machine, desired finish, coolant and or lack of coolant. Even with all this you have to use some common sense. Brass is very flexible and forgiving, unlike steel. You need to first find the surface feet of that material first.

http://findarticles.com/p/articles/mi_m3101/is_n8_v69/ai_19115043

Iscar has a handy calculator at their web site

http://www.americanmachinist.com/Calculators/SpeedsFeeds.aspx

http://www.cncci.com/resources/tips/g96.htm

Good Luck


TermDefinitionchip load (http://www.toolingu.com/definition-200300-14178-chip-load.html) Another term for feed per tooth that refers to the thickness of chip material removed by the cutting edge of a tool.CNC machine (http://www.toolingu.com/definition-200300-14160-cnc-machine.html) A sophisticated machine tool run by a computer that can perform mulitiple machining operations in the same setup with a variety of tools. CNC machines require a programmed speed and feed rate value.column-and-knee mill (http://www.toolingu.com/definition-200300-14162-column-and-knee-mill.html) The original and most basic type of mill that is used to machine flat or rectangular workpieces.constant surface speed (http://www.toolingu.com/definition-200300-14169-constant-surface-speed.html) A mode on a CNC lathe that adjusts the spindle rpm as the tool travels toward and away from the spindle's axis.depth of cut (http://www.toolingu.com/definition-200300-14176-depth-of-cut.html) The thickness of material removed by one pass of the cutting tool. engine lathe (http://www.toolingu.com/definition-200300-14161-engine-lathe.html) The original and most basic type of manual lathe that is used to make cylindrical workpieces.feed (http://www.toolingu.com/definition-200300-14158-feed.html) The rate that either the workpiece or cutting tool changes in position during the length of the cut. Feed typically defines a linear or contour movement.feed per revolution (http://www.toolingu.com/definition-200300-14179-feed-per-revolution.html) The linear distance that a tool advances during one rotation of the workpiece or cutting tool. On the mill, feed per revolution (fpr) may be used to convert from feed per tooth (fpt) to either inches per minute (ipm) or millimeters per minute (mm/min).feed per tooth (http://www.toolingu.com/definition-200300-14177-feed-per-tooth.html) The thickness of chip material that each cutting edge of a tool removes with one pass.hardness (http://www.toolingu.com/definition-200300-14159-hardness.html) The ability of a material to resist scratching, indentation, or penetration. Workpiece materials with increased hardness generate more heat and are more difficult to machine.horsepower (http://www.toolingu.com/definition-200300-14163-horsepower.html) A unit of power used to describe machine strength. A machine with increased horsepower has a spindle that can exert a greater amount of force.inch per revolution (http://www.toolingu.com/definition-200300-14170-inch-per-revolution.html) The distance in inches that the tool advances during one complete revolution of the workpiece. Inch per revolution (ipr) is an English measurement for feed on the lathe.inches per minute (http://www.toolingu.com/definition-200300-14172-inches-per-minute.html) The distance in inches that the entire tool or workpiece advances in one minute. Inches per minute (ipm) is an English measurement for feed of a rotating cutting tool on the mill or lathe.live tooling (http://www.toolingu.com/definition-200300-14174-live-tooling.html) Rotating power-driven cutting tools, such as end mills and drills, that are held in the turret of a lathe. Live tools can perform machining operations off the part centerline while the workpiece is held stationary in the spindle. millimeter per revolution (http://www.toolingu.com/definition-200300-14171-millimeter-per-revolution.html) The distance in millimeters that the tool advances during one complete revolution of the workpiece. Millimeter per revolution (mm/rev) is a metric measurement for feed on the lathe.millimeters per minute (http://www.toolingu.com/definition-200300-14173-millimeters-per-minute.html) The distance in millimeters that the entire tool or workpiece advances in one minute. Millimeters per minute (mm/min) is a metric measurement for feed of a rotating cutting tool on the mill or lathe.part program (http://www.toolingu.com/definition-200300-14164-part-program.html) A series of numerical instructions used by a CNC machine to perform the necessary sequence of operations to machine a specific workpiece. pi (http://www.toolingu.com/definition-200300-14168-pi.html) A special constant value that relates the diameter of a circle to its circumference. Pi is roughly 3.14 and is used to find the circumference and area of a circle.revolutions per minute (http://www.toolingu.com/definition-200300-14165-revolutions-per-minute.html) The number of revolutions that a spindle or cutting tool completes in one minute. Revolutions per minute (rpm) is a measurement of speed in both English and metric systems.roughing (http://www.toolingu.com/definition-200300-14175-roughing.html) A cutting pass that emphasizes high material removal rates at the possible sacrifice of surface finish or accuracy.speed (http://www.toolingu.com/definition-200300-14157-speed.html) The rate that the workpiece surface and cutting tool pass each other at the point of contact. Speed typically defines a rotational movement.surface feet per minute (http://www.toolingu.com/definition-200300-14166-surface-feet-per-minute.html) The distance in feet that the workpiece surface or cutting edge travels in one minute. Surface feet per minute (sfm) is an English measurement for speed.surface meters per minute (http://www.toolingu.com/definition-200300-14167-surface-meters-per-minute.html) The distance in meters that the workpiece surface or cutting edge travels in one minute. Surface meters per minute (smm) is a metric measurement for speed.

[Frank Triana]

http://www.toddlertime.com/machining/feeds.htm