[rando]

I spent an hour on the phone with support yesterday. I wanted them to show me how to create a tool within BobCAD, all the poor kid did was clik around, and say..."I know there's a way...if I could only remember..." Needless to say, he never remembered.( I think tech support knows as much as I do about BobCAD...and less about machining) If someone could tell me how to do this.....I'd start machining...and quit talking so much...

I make mainly square , buttress, and acme threads for oil rig applications. eg






the square threads are using a grooving insert, and not that difficult to figure.
My main hang up, is that BobCAD does all of its figuring based on a pointed insert, and I can not figure out how to cut the threads like I need. I've been jacking with it for two days.... The geometry option within the tools area only says "CERAMIC" ...wouldn't that be insert composition....NOT GEOMETRY???...Please help

:drowning::drowning::drowning::drowning::drowning:

[bobk]

I don't know if this will help, I use the theoretical center of the tool cutting face for my tool path.

[rando]

As do I. Have you tried using th threading feature, or do you just handwrite canned cycles for your threads?

Also, do you have to use layers to make a roughing cycle to leave the material in the z as you want for finishing?

If I don't draw duplicate parts, with paralll lines offset where I want the material left in the z, and just try to post code leaving .005 in z, and .1 in x for finishing, it leaves .1 in both x and z.

Have you had this issue, or am I doing something wrong?

[bobk]

I have not used that feature, I just write canned cycles for threads. I'm not sure I understand your second question.

[rando]

I'm not sure I understand your second question.

Have you had any problems when roughing and finishing a profile. It seems to me that when I use the tool nose radius comp in bbcdv22 for roughing, it is not correct. If you use this feature, it leaves the same amount of material on part faces as it does the diameter, no matter your input for material to leave in z? Mine does anyway, and I don't know if I am doing something wrong, or the software writers have made an error. The only way i can get around this is to make another drawing of my part, offset in the amount I wish to leave, and not use the tnr comp, and to leave 0.00 in x and 0.00 in z.:violin:

[bobk]

I don't have ver. 22, I only went to 20. I do understand what your saying now. When I use ver. 20, I only rough within approx. .02-.03 then I do a profile finish cut. I wouldn't be surprised if the program isn't working properly. Bobcad has many features that don't work quite right.

[mmc005]

I don't use the tnr comp. for roughing, I just input the amount that I want left on the part and it works fine. I'll have to try it and see if it works that way for me. Are you using canned cycles or seperate moves?

[rando]

seperate moves....no problem with memory capacity yet, and have just recently learned what a cnned cycle for threading should look like.....

how much material do you normally leave in z? I am self taught, and machine by feel, and .01 feels pretty aggressive to me, but it sure makes part pretty...using a 55 deg. cutter generally.

[mmc005]

I usually leave .010 on the z for my finish pass and I use an 80 degree diamond shaped insert with a .032 tnr for roughing. For my finish pass I use 35 degree insert with either a .032 or .016 tnr depending on what I am turning. I do know that setting up your tools in bobcad has alot to do with what your output numbers will be. If you have the wrong cutting angle on you insert setup it will not give you the correct numbers for your program. I have had good luck with the tnr comp. for finish turning and for grooving, I haven not lost a part yet due to size or position output from bobcad...............Knock on wood......

[rando]

I haven't scrapped anything either, as this is my only cad experience in a few years, and I am very careful about reading the code before running the part. I find this way more reassuring than the pretty little cartoon verify that came with v22. I am finding my little ways around the quirks in the software, But I like the consistency of using the tnr for roughing too, and I believe that BobCAD has made an attempt at this, otherwise they wouldnot have a tol nose radius comp option in the roughing feature... I think it is a problem actually in the current settings area where you can select either theoretical tip or arc center...or something to that effect. I think rather than posting code for theoretical tip, it is posting for arc center, but only for roughing, as it does work for finishing, and grooving. If people would e-mail Chris, and let him know...in a friendly manner, they'd be surprised that he might actually do something about it.

[mmc005]

lol @ the little cartoon, so true. You may have a good point about the theoritical point vs. center of radius. I had an issue with that when grooving in the last update, also, I just remembered that with grooving, sometimes you need to hit the calculate toolpath a couple of times in order for the tool path to show up correctly on the drawing. Also you could try changing the position/direction in your tool page. Maybe it's "stuck" on a different side/direction ie 2 or 3 instead of 1. Just a thought on that though. Glad your up and running with the software, when you have all the bugs figured out with a workaround it does get easier.

[rando]

lol @ the little cartoon, so true. ............................ Glad your up and running with the software, when you have all the bugs figured out with a workaround it does get easier.

I just thought that was worth repeating for any other newbies that may be reading this.....Be Patient, BobCAD has it's little quirks, but as with most things...."With Time It Does Get Easier"