HST Tool holder Collisions

[andrewgore]

After much toolpath regeneration amongst other things, I decided it is time to ask why my toolholder is crashing into my work in my HST's. Here is the scenario:

12mm ball end mill

19mm Tribos holder

tool length = 1.7 (From bottom of holder)

Toolpath: HST Core Roughing

DOC= 0.095

stepover= 30% (.078" min .142" max)

Spindle = 16,000rpm

Trochoidal cuts on (default settings)

 

Key ingredient here:

HOlder = 19mm holder 4.1" OAL

Holder Clearance = 0.1" (though I would play it safe)

 

Now, in mastercam I told it that my tool was only hanging out 1.68" instead of the 1.7" that it is. I figured this would just aid in added clearance if the need be.

 

On with the toolpath, I get down to where the toolpath is cutting. The part is 3" tall. Imagine it is kind of like a half circle with ribs on the sides of it. The tops of the ribs are below the top (0) by about 1". For some reason Mastercam feels it is OK for the toolholder to hit the tops of these ribs, amongst other things. I have holder clearance set to .1" which should in essence be more than enough. Is mastercam not taking into account that this is a roughing operation (leaving .010" on sidesfloor) and not "remembering" that there is stock on the top of things? What am I missing here? Any thoughts or Ideas would be much appreciated. I'll give my reseller a call here in a bit after I get the machine back up and running. Boggeling me here.

 

Andrew

ps

x2MR2

[Wise-ACR]

Can you put the file on the FTP site.

[andrewgore]

I made a file of something "like" what I am cutting. Good example where others can investigate, without customer situations I upped it to my server. Check the link:

z2g File (right clicksave as)

 

Do a backplot, ignore the crashes on the outside of the part (assume that stock is gone), but note the collisions on the tops of the bosses. This is a model I drew up quickly for a reference. The result was worse on the actual model I have been working on. During the roughing operation I used on the actual part, it left far more stock on the tops of the bosses; resulting in the tool holder rubbing rather signifigantly (more than 0.050″). Fun times as you can imagine. Believe me, I would love to verify all my parts, but when you have to wait 35+ minutes for a verify on one operation.....I feel like Any help is much appreciated. Thanks

 

Andrew

[FITIN IRISH]

Andrew I had a look at you file. I used surface finish radial. I sent you an email

[andrewgore]

I knew I could do a radial toolpath, my concern is the fact that my toolholder crashes into my piece when using the HST Core roughing operation. I've got the other operations for this done, but have had to have my tools hanging out further than I would prefer.

 

Andrew

[Roger Peterson]

A couple of things with holder gouge detection:

 

1. the clearance is an X/Y clearance only. Not Z clearance.

 

2. Gouge detection checks the holder against selected geometry (surfaces or solid). So if core roughing is leaving .050" on top of an island it is possible to get a gouge.

 

 

Does the gouge show up on the part, or does it also show in backplot and verify?

[FITIN IRISH]

I had a look a this file. I have found that when I collission check it there are no collissions but when I use the same STL file in Verify I get a crash.(paused on collission.)

[andrewgore]

Shows up in part and on verify. I would love to verify all my operations, but that as I said before, doesn't work well when you can't use "turbo" mode (part not completely based on TOP TOP planes. I don't understand though why when its told that the tool is hanging out the 1.x" why wouldn't they take the bottom of the tool holder into consideration? Mastercam knows that the tool is only so long, and the tool holder essentially starts where the tool ends, not only that, but if you look at the verify of that part, you can see just how far over the gouging occurred.

 

I've since modified my programs, and made my tool hang out as far as I needed. I guess my questionconcern comes back to why on earth wouldn't they take the bottom face of the tool holder into consideration? I can't imagine that it would be that hard to add into the program if holder checking in XY axis is already there.

 

Andrew