Roughing Strategy

[paulfell]

I have roughed a steel billet (approx 30'' square) as per pic attached, I have used Surface Rough Pocket with a large Facemill. I now wish to continue with roughing using a smaller tool,

I know there is a method/ toolpath which takes into account previous ops - this will obviously save a lot of roughing time. I have never used this method or toolpath - although I know it can be used, could somebody point me in the right direction on how to do this  ( I will then research it more before using it ). There maybe another method of saving stock model and using that as stock for next toolpath ?. Any advice on method/ toolpaths would be welcome - thanks

[crazy^millman]

Not with Surface Rough Pocket, but with Opti-Rough yes you can. You can try making a stock model using that Operation and see if it gives you the model after that operation then go back and use Opti-Rough as Rest material with the smaller tool. 

[paulfell]

so I cant use surface restmill with surface rough pocket?

 

[paulfell]

I have just tried surface restmill - it wont generate a toolpath - comes up with error - ''cant extract at least one solid face''

[crazy^millman]

What version of Mastercam are you using?

[nickbe10]

12 minutes ago, paulfell said:

I have just tried surface restmill - it wont generate a toolpath - comes up with error - ''cant extract at least one solid face''

As Ron said the best way to go here is opti-rough. As always there are several ways to skin the cat in MC. Here's what I do:

Run your first roughing toolpath and save the result as an .STL file.

Select all surfaces / solid faces you want to machine as drive

Go to the opti-rough toolpath and select this .STL as the CAD file selection on the toolpath tab(top tab) on the tree.

Go to the restmill tab and select CAD file option.

MC will now compare the  .STL and the finished surfaces and only machine areas where it can cut more material given the other parameters on the opti-rough tabs. I usually do a fairly large step down and then use the step up to get the "smoothing" I want.

You can also use the previous ops as Ron said but sometimes the results aren't as good for me. Only problem with using the CAD file option is that under some circumstances it will "lose" the CAD file, but if it does it will tell you and you can just reselect it.

This is a great toolpath and it is worth playing around with the parameters to see how you can effect the toolpath. It is also good as a first roughing toolpath if you have irregularly shaped stock. Just save your stock model as an .STL and do above.

Just got a note saying Ron has replied as well so hopefully you get a different way to do it. Sometimes one method works better than another for a given geometry so it's good to know more than one.

How's it going over in "The Republic of Scouseland", haven't been for a while now.....

[paulfell]

using x9 - can i use opti rough with stl file saved from surface pocket toolpath - this toolpath is already a couple of hours into cut - so will have to go with it now. Liverpool is great - massively improved city   over last 10 years - where does it say where im from ?

[nickbe10]

22 minutes ago, paulfell said:

using x9 - can i use opti rough with stl file saved from surface pocket toolpath - this toolpath is already a couple of hours into cut - so will have to go with it now. Liverpool is great - massively improved city   over last 10 years - where does it say where im from ?

Opti rough with CAD as rest material will work with any .STL. That's why you can use it as a first roughing op with an irregular shape stock.

Its pretty much my "go to" 1st roughing (without CAD restmill option usually) in 3 and 4 axis (and some 5 axis depending on geometry). So many options......I would encourage you to spend a couple of hours playing with the different settings. You can also restrict the area you are working with a containment and z depth region (steep / shallow tab) so you can have different settings for different areas of the part to suit the geometry in that area.

I have read posts here by Ron where he has used techniques for "forcing" the system to his will that I wouldn't even have dreamed of probably because he makes such "tiny" parts, any tips to add Ron....?

It was the accent that was the dead giveaway......I lived in N. Wales for many years so I had a number of "scouse mates"....

[crazy^millman]

The answers by Nickbe are spot on.

Here is something different to think about I would bring the STL and save to a level. From that Level I would make my stock model. That stock model would be my Stock for reference for the Opti-Rough. When you use a file it converts this tool path to Opti-Rest that will then run your tool using that to get it where it needs.

[paulfell]

Thanks all- I used opti rough toolpath- using stl model, I didnt understand about making my stock from stl on a level, I did put it on a level anyway for reference. but saw no option to pick it from the level - only to select the file ( hope that makes sense). Anyway - it worked well 

 

[jaydenn]

Stock model and Opti-rough work really well.

I routinely have files with 10 or 20 stock models for each op to get virtually flawless roughing, very quickly. The regen time goes up, but whatever.... Go get a coffee.

I would recommend NOT using stl files because they don't have any associativity(real word???) with the previous ops; stock model does.

J

[crazy^millman]

22 hours ago, paulfell said:

Thanks all- I used opti rough toolpath- using stl model, I didnt understand about making my stock from stl on a level, I did put it on a level anyway for reference. but saw no option to pick it from the level - only to select the file ( hope that makes sense). Anyway - it worked well 

 

Yes I have asked for just using a level stick model selection, pick the stl as the model in stock model and good to go. It says solid model, but you can pick an stl as the reference model. 

[paulfell]

Thanks for reply, no access to Mastercam until next week now -  without looking through the toolpath options I am not entirely sure what you mean by stock model ?. I used method described n thread - saving an stl file from stock produced by previous ops - then picking it as a CAD file  - I assume from replies there is another way  - anything to pint me in the right direction on other method would be welcome - I will give it a go next week - thanks

[David Colin]

You may appen your model from your stl file into your Mastercam file. Then you can use it to create a 'stock model toolpath' (right click in operation manager and you should see it at the end of mill/lathe toolpaths in a separate section)

In optirough you can select a previous operation and you ll pick that stock model operation you just created

[huskermcdoogle]

On 6/9/2017 at 7:59 PM, jaydenn said:

I would recommend NOT using stl files because they don't have any associativity(real word???) with the previous ops; stock model does.

Unless like for the one place that stock model would be useful for me that mc crashes no matter what... (The problem is logged in R-11614.)  Apparently it doesn't like large round tools with rotary motion.  Best to create stl using verify or mach sim and import back in, but in this case associtativity isn't a big deal. 

[Matthew Hajicek - Singularity]

I do it with stock model.  I like the associativity and not having to worry about external files.