Newbie- How to cooling fins?

[pmsmichelle]

A basement hermit hobby newbie MasterCamer 9.1. Needs recommendations of best approach to drawing and machining cooling fins. My part is flat rectangle needs fins on four sides. I have drawn the top view rectangle larger than my stock with .100 wide fins .100 apart. Trying to use pocket I found "open pocket", does that automatically open both ends? Do I need the rectangle drawn at all? Just lines .100 apart without perimeter rectangle lines shown? Do I use pocket? Can I pocket multiple times? Am I headed in the right direction?
Mike

[Superman]

To draw it,
set view and construction to Right side, in this setting create a profile of the part like you would do a section drawing,, make sure you have drawn it below the Y0 line (<F9> to turn om the datum axis lines) , Y0 from the SIDE is Z0 when your planes are re-set back to the TOP

You should have 1 continuous chain, change your color and level, now create, solid, extrude this chain in both directions by 1/2 the distance of your finished part

If you can't do solids, then create surfaces.
select another color and level, create edge curves around the base, draw lines down the centre of the fin valleys and extend them to go over the edge by the cutter diameter you wish to cut the valleys with

To Program it,
-create stock material
-( Top face) Face, don't select any geom ( defaults to the size of stock) top of stock=0.1" absolute, depth=0 abs.
-( Side walls ) 2D_Contour, use base curves ( select the chain going CWise), top of stock=0 abs, depth = -0.02" increm. cut depths ON and set to.12" comp=wear, side=left, lead in/out ON and set tangent line=0.1, arc rad=0.1, sweep=90 and copy to lead out ( use centre arrow )
-( Fins ) 2D_Contour, use lines on valley centre ( play with how you select the lines-pick nearest the end where you want the tool to start, and the order you want to do them ) , comp=OFF, side=left, ( this sets the cutter to cut on the line ),lead in/out OFF ( if you want to extend the toolpath line a little further, turn lead in /out ON but set leads OFF inside the dialog box and adjust the ends to suit.

[pmsmichelle]

Thanks much, this is helpful.
Drawing: Hadn't found that <F9> datum lines yet. Those may clear up some questions I have. I can understand Y on the side view is z at the top.

I don't have solids. Color and Level are interesting. Could you explain those a little more? If I change color of a line what does that do for me? Is it advisable to have different levels different colors to keep it clear? Are levels and surfaces the same? How do I create surfaces? I recall when I tried to post or was it toolpaths that a window would open "no drive surfaces detected" or somthing like that.

I didn't understand "create edge curves" around the base? The base of the rectangle stock drawn in side view?

Program: "Create stock material" What?

Top face: Not sure why "Face" Are you saying the setting I want is .1 above the top of the material? Why?

Side walls: 2D Contour: I didn't know I needed to use the side view to cut the top? So you have to draw two views to cut one? Is this telling MC to follow that side contour when cutting the top? If that is the case pretty smart stuff? Again I don't understand "base curves"? Also seems like this side view has more info/settings (which I also have questions about) and importance than top which I am cutting?

Fins: 2D contour: I think I undrestand most of this but comp=OFF"?

A million questions but enough for now.
Thanks again.
Mike

PS. I am trying to locate a good training book. Have you recommendations which one?

[Superman]

I don't have solids. Color and Level are interesting. Could you explain those a little more? If I change color of a line what does that do for me? Is it advisable to have different levels different colors to keep it clear?
It makes seeing the acutal part a little clearer, and would give you a better 3D perspective

Are levels and surfaces the same?
no, levels are like sheets of clear plastic with whatever geometry on each level, turn OFF a level would be like removing that sheet

How do I create surfaces?
play with this to understand, basically, geometry drawn at the same construction depth can be " drafted" into a surface... go "CREATE", SURFACES","DRAFT", select the entities to define the surfaces, "DONE", "LENGTH" type in a value on the command line and "Enter"

I recall when I tried to post or was it toolpaths that a window would open "no drive surfaces detected" or somthing like that.
You have to have surfaces or solids displayed on a visible level

I didn't understand "create edge curves" around the base? The base of the rectangle stock drawn in side view?
TOP, so effectively it is the base of the part

Program: "Create stock material" What?
go "TOOLPATHS","JOB SETUP" will give you that area for setting your part up

Top face: Not sure why "Face" Are you saying the setting I want is .1 above the top of the material? Why?
FACE= meaning a machining operation

Side walls: 2D Contour: I didn't know I needed to use the side view to cut the top? So you have to draw two views to cut one? Is this telling MC to follow that side contour when cutting the top? If that is the case pretty smart stuff? Again I don't understand "base curves"? Also seems like this side view has more info/settings (which I also have questions about) and importance than top which I am cutting?
all operations need to be done from TOP VIEW , you can view in isometric to have a good perspective on what is going on

Fins: 2D contour: I think I undrestand most of this but comp=OFF"?
Yep

[fizzissist]

I've amazed myself at how many times I've made something more complicated than it needed to be...

Had to make a bunch of cooling fins recently, and all I did was draw a bunch of parallel lines, starting with one at 0,0 and extended it 1 diameter of the tool beyond the needed length in both directions. Offset it repeatedly till I had the number of slots needed.

Then, select each line sequentially, but starting selection at opposite ends for each successive line, do a simple contour path using multiple depths if necessary, but turn off cutter comp.

The tool should start just outside the material and do the first slot, exit the material move up to the next and cut it the opposite direction....and so on.

Not nearly as exciting, or as educational as designing a real model...but quick and simple.

[fast89]

I just did some two weeks ago. I just drew the first fin, then translate between points. You can tell it how many times to translate it at what offset. To assign toolpath, you can just select contour, then window rather than each individual chain. I was pretty conservative on my speeds and feeds and it ran for over 3hrs and the program was something like 12000 lines. Thank god for cnc lol.

[fizzissist]

Or...
Draw one fin, generate one toolpath, then use the toolpath translate function.

[pmsmichelle]

Thanks guys, I haven't been able to try any of these but will soon. I imagine I'll have more questions once I try these. Too bad work gets in the way of hobbies.
Mike

[lovecnc2003]

thanks

[pmsmichelle]

If I want to use a endmill the same size as the cooling fin valleys. Is it possible to draw a line and program the chain to follow it on center? It appears that its either left or right of the line?
Thanks
Mike

[Superman]

Yes,
Turn cutter comp OFF

Do not use "Control", "Wear", "Reverse Wear", or "Computor" as these will add the tool radius to the toolpath.

Lead in / out can turned ON to use the extending / shortening of the ends, but turn OFF the lines and arcs component ( or set them to zero). XY offset should be set to zero.

You can extend the actual contours on both ends to be outside the part, to eliminate the lead in/out section, and you can use "Ramp" "by Depth" to get a more efficient path, play with this area to get a better understanding of controlling a tool to do zig-zag on or around a contour chain