Slot with side cuts from single line geometry?

[Hugh.Venables]

I have to produce a lot of slots (mostly curves) on a flat surface. The centre lines of the slots

have single line geometry. Is it possible to generate a MC toolpath from the centre line

geometry that roughs the middle and then takes a climb finishing cut each side of the

slot?

Thanks, Hugh Venables.

[Guest CNC Apps Guy 1]

Not to the best of my knowledge. I did this same thign but ended up creating some geometry and using surface finish project to get the desired effect.

[Kenneth Potter]

You might try offsetting the centerline geometry 1/2 the slot width on both sides.

 

Or compensation in the computer "left" & chain the

Slot centerline twice.

 

Then go back on the second chain & reverse the channing direction.

[Glenn Bouman]

You can chain a single line and have the tool contour around the slot.

Go Toolpath, contour, chain partial, select the line and then turn on the Wait option and select the line again.

[Fred from Université de Sherbrooke]

Glen,

I like your technique, but do you know why it does'nt work with splines? I have to convert them to arcs.

[Hugh.Venables]

Thanks Guys.

 

James, I don't follow why you would use project.

 

Kenneth, I was hoping to avoid creating extra geometry. Using cutter comp. is a good solution. If I create a 0.008" cutter I will get my 0.004" sidecuts.

 

Glenn, I see, 'wait' allows me to select the same entity twice in one operation. There are 15 chains in the job. If I reverse the direction I have noticed in the past that the direction of each chain reverses but not the order in which the chains are done. This leads to a lot of unintended rapid moves. Any solution to this?

 

Fred, is it just 'wait' that won't work unless the splines are broken to arcs?

 

Hugh Venables.

[Glenn Bouman]

Hugh to answer your question, check out this example CENTERLINESLOT.MC8 on the FTP site in the MC8 directory.

 

You may need to set a -ive "XY stock to leave" depending on the size of the slot compared to the size of the tool.

 

The wait works with splines but the compensation about itself(spline) is not supportted.

[Kenneth Potter]

quote:

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If I reverse the direction I have noticed in the past that the direction of each chain reverses but not the order in which the chains are done. This leads to a lot of unintended rapid moves. Any solution to this?

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Use the tool path editer & force those pesky Z rapid retracks out.

 

Kenneth Potter

[Glenn Bouman]

This will not give you any extra rapid moves.

[Hugh.Venables]

Arrggghhhhh!!!!!!

Glenn, as an often frustrated computer semi illiterate, I have been living in constant fear since I joined the forum that sometime I would need to access the FTP site. Sure enough, I have tried right and left clicking on "centrelineslot.mc8", the file symbols to the right and the question mark symbol to the left. None of the pop up menus contain "copy to folder" but I really only wanted to have a look which I think I should be able to do without copying to folder. The best I got was a row of letters and symbols across the top of the page. This is a bare bones PC set up to just use MC, maybe it needs some more software loaded to be able to look at the FTP site. What does FTP stand for? How is it different to a web site? What do I do next? Who am I? Why am I here?..........

 

The job is the base of a sundial in 1/8" copper. I intend to do it with a tapered d-bit. Because copper is so filthy to machine I thought my best shot would be to rough it out and then climb side cut both sides to finish.

 

Kenneth, what I meant about the extra rapid moves was this. When you plan a job with a lot of features, you select the features in some logical sequence so that the finish point of one is close to the start point of the next. If you then reverse the chaining direction the sequence doesn't reverse so you can get an illogical sequence in terms of finish and start points and the rapid moves to get from one feature to the next.

 

Thanks. Hugh Venables.

[cadcam]

Hugh,

I have emailed you the file hope this helps.

 

Love your post on the New Member post.

Keep up the good work with those kids.

[Hugh.Venables]

Thanks Jay,

You're an absolute treasure as is the entire eMastercam site.

I thought I would be able to look at a file on the FTP site without downloading it. I now presume this is not so. What had me fooled was that when I right clicked on the file name I didn't get a "copy to folder..." option in the pop up menu as per the FTP instructions. I had (among others) "save link as..." . I thought "link" meant a link to the site, I didn't realise it meant a link to the file. Maybe that's a Netscape thing. Designed to confuse computer dummies like me?

 

However, it hasn't finished with me yet. If I click the file you sent me, Mastercam opens and opens the file. Great. I can also save it in the Mc8 folder and re-open it OK. But if I save the file from the FTP site to the MC8 folder, (using Netscape), then open Mastercam and open the file I get "Incompatible version numbers. Run Mc8 file converters". I don't understand what the problem is or how to fix it.

 

Glenn, thanks. I got your e-mail, but there doesn't seem to be any attachment to open. I have got it from Jay and had a look at it. I can't see how you have achieved four tool paths from only two chains? I can only imitate the tool paths by selecting the lines in both directions, which gives four chains. But mine doesn't roll around the ends of the lines, it retracts, rapids to the other side and plunges back in. Your NCI file is 7.9K and mine is 11.5K. There sure is a lot about MC that I don't know.

 

Thanks a million for your continued help guys. Without the forum I think I'd give up and go home or go crazy.

 

Hugh Venables.

[Glenn Bouman]

The "Wait" option under "Partial Chaining" allows you to select the same profile without starting a new chain.

[cadcam]

Glenn that works great.

I have never used that and it is such a simple tool but a good one.

Like I say ,I learn here tooo.

[Hugh.Venables]

Glenn thanks again. How on earth did you ever figure out how to do that. It still took me a while to figure out that for the curve the 'first entity' is selected at the start and the 'last entity' is selected twice, once at the end and again at the start. For the line the first and last entities are both at the start of the line. Not so obvious. This is a great tool for quick and dirty slots.

 

Unfortunately, unless I can prevent the tool paths from rolling around the ends of the lines, I can't use it for my job (a bordered grid of lines). Can I control this?

[Glenn Bouman]

quote:

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How on earth did you ever figure out how to do that.

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Just read the help file.

 

quote:

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I can't use it for my job (a bordered grid of lines). Can I control this?

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I would have to see the file first.

 

[ 02-14-2002, 09:32 PM: Message edited by: Glenn Bouman, In-House ]

[cadcam]

quote:

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Just read the help file.

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Now there is a NEW THOUGHT