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One other caveat:  If you're making a 'relatively heavy' cut with a fairly thin (or long), flexible cutter, choose only climb milling.  There is a tendency for a bit to 'hog' when it flexes in conventional cutting, and it may mar your finish.  In climb, if it flexes, it pulls away from the surface slightly.  If it doesn't give a perfect finish on the first pass in climb, another pass at the same setting will usually clean it up satisfactorily.

Lloyd
2
Hello

Yes you can do that with only one MOP.

In the "Cut Width" give a value = tool diameter + the extra material to remove, in your case 10 + 5 = 15

Define a Step over (as a fraction of the tool diameter) that match the passes you want, in your case, to get passes of 0.5mm, you must give a step over = 0.05 (0.05 * 10 = 0.5mm)

If you want to end up with a smaller passe, add the value of this passe to the CutWidth, ex: if you want to finish with a passe of 0.1mm, enter a value of 15.1

You can set the "Milling direction" to "mixed" if you want to cut back and forth.

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David
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Hello   have generally got on very well with cambam for profiling and pocketing, however with mulitpe side mill passes i'm struggling to set that up easily

for example say I'm looking to side mill the faces of a block of rough sawn acetyl (to a good finish so want to side mill the whole face in passes rather than successive depth cuts) have resorted to multiple MOP's each leaving less and less of a roughing clearance.  cb file attached

Is there a slicker way to program this please?
Thank you in advance   
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Quote
With any roughing pass, I leave material for finishing. 
But I find that 'cusps', 'spurs', or 'horns' (whatever you might call them)  remaining in any sidewall cause surface finish variations in a finishing pass. 
I want uniform surfaces on which to finish, regardless of whether I use ordinary pocketing or trochoidal methods.

Yes I thought about the profile cut when developing the pocket above, as this was a pocket
on the inside of the machine, I wasn't so worried about the cosmetics, I didn't want to damage
the tool, I looked at the file and I used -0.15 mm roughing clearance + height of the peaks 0.5 mm which cleaned up the pocket
side wall (I could not see any defects or hear it in the cut).
This equates to only 11 percent stepover, so I guess there wasn't enough impulse force caused by the undulating surface to excite the tool.

In the photo you can see a speed run of the troch mops pocket in the file earlier, I didn't run the production file like this as chip clearance
and tool heating were the limiting factor, during the course of developing the pocket (a few months) I added an extra air nozzle and upgraded
the spindle I had no flood cooling and no intention to do so.
In the pic I flooded the pocket as it was developing.
 
Original Standard CB pocket 18 minutes 44 seconds.
Troch mop +FRA                     10 minutes 18 seconds. Speed run

I've left one of the pic's as a full size jpg so that you can zoom in and look at the surface finish.

Dave
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Scripts and Plugins / Re: Trochoidal Pocket & Profile MOPs plugin (HSM)
« Last post by lloydsp on April 21, 2024, 22:37:50 pm »
With any roughing pass, I leave material for finishing.  But I find that 'cusps', 'spurs', or 'horns' (whatever you might call them)  remaining in any sidewall cause surface finish variations in a finishing pass.  I want uniform surfaces on which to finish, regardless of whether I use ordinary pocketing or trochoidal methods.

Lloyd
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Scripts and Plugins / Re: Trochoidal Pocket & Profile MOPs plugin (HSM)
« Last post by Bubba on April 21, 2024, 21:15:38 pm »
That's the thing Lloyd Troch mops are roughers and need to be followed up with a finisher
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That's why I always 'rough cut' pocket leaving enough material for profile pass.
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Scripts and Plugins / Re: Trochoidal Pocket & Profile MOPs plugin (HSM)
« Last post by dave benson on April 20, 2024, 23:45:52 pm »
Quote
you stand the chance of leaving 'spurs' in your pattern with even a slightly-worn bit

That's the thing Lloyd Troch mops are roughers and need to be followed up with a finisher
If your have your step over aggressive enough there will be scalloping on the walls of the
pocket (this is a good sign you are in the ballpark).

I like the troc mops, they have their superpowers,but they are not a universal panacea for
all pocketing situations, some simple pockets  for example a square with rounded corners
where the radii of the corners are somewhat larger than the diameter of the tool  then a simple
pocket mop would be a better choice, however if the pocket has even just a little more complex geometry
then the troch mops offer a significant speed up in cut time.

Used with a dedicated roughing cutter and one of the feedrate adjusters which rip out the
positioning moves and replaces them with rapids and vary the feedrate to keep the chipload
constant make for fast pocketing between 40 -60 % faster than a standard pocket.

I had a look at the production files and roughly a third of them are troch mops the rest are
plain pockets where the pocket has simple geometry like rounded squares and rectangles with
radii larger than the tool radius.

Dave
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CamBam help (General usage) / Re: trachoidal pocket start point
« Last post by dh42 on April 19, 2024, 22:06:09 pm »
Re

Also another thing to know is that if you use more than one shape in a trochopocket mop, if you let the start point as "not defined" all shapes will be cut, but if you manually define a start point into one of the shape, only this one will be cut.

If needed, you can reset the start point by setting the start point to "default" in the start point property context menu.

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David
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CamBam help (General usage) / Re: trachoidal pocket start point
« Last post by Chip Owner on April 19, 2024, 21:13:02 pm »
Hello

With a trochopocket, the start point will define where the initial spiral start. I think it is a good idea to place the start point  in a position that allow to get the maximum spiral cut (to speed up the cut)



Also in some case it is necessary to make the cut in two session because on some designs the pocket will not be cut totally if the tool can't go from an area to another (because its diameter is too large)



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David

Much appreciate thank you. That makes a lot of sense.
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Scripts and Plugins / Re: Drag-Knife Plugin
« Last post by dh42 on April 19, 2024, 19:16:36 pm »
Hello

Quote
Please note that the code changes all polylines to CW direction so changing polyline direction in CamBam has no effect for this plugin.

Yes, and changing the CW/CCW do not change the position of the polyline start point.

Quote
That's a good trick to rotate the circles, maybe this could be added to the plugin.

The problem of the start point is the same for any shape, not only circle, I think it is the job of the user to set it at the right place so the arc start in the waste stock ... with only a polyline and no internal/external info as on a profile mop, the plugin can't know if you want to cut a hole or a disk and where is the waste.

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David
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