This may be of interest to exactly one person, me, but will GT support creation of pin and slot devices?   I use these on my Antikythe ra Mechanism models.   Right now I bring the gears into a CAD program and create the slots myself.  It's not difficult, but if I didn't have to do this step, life would be a little bit better and it would make what I view on the project screen that much closer to reality.

Googling pin and slot will show lots of examples, the paper On the Pin-and-Slot device of the Antikythe ra Mechanism, with a new applicati on to the Superior Planets http://www2.ups.edu/faculty/jcevans/Carman%20Thorndike%20Evans.pdf shows the details and how many of these I have to work with.    It also details the math involved.

Add me to the list of folks who would really like to be able to cut bevel gears laying flat.  I have a CNC router and just need a couple bevel gears for my Antikythe ra project.

Are the teeth on the rack supposed to change like that?

I understan d, everythin g effects every other thing, I have a pretty good workaroun d where I pull it all into a CAD program and move the holes to different layers so I know which ones to cut for which plate. 

I have a very simple bug report then.   On my system version 4.7, when I close the active document, it closes the program. 

Thanks!

Kevin

If you want to take a break from that.   My request for additiona l plateing would be very much appreciat ed.   I am some complex mechanism s that have plates in the middle, not just at the front at back.

Thanks!

If you managed to pull off all these things you would be a hero to clock makers everywher e (even more so than now).   You might even get knighted by the queen I suspect.    Sir Art of the Gearheads .   Perhaps even get your own gear shaped castle and get to wear funny hats to formal occasions .

Thanks!

-Kevin

My thing is building astronomi cal clocks (and one of these days I'll get one to the point of posting pictures and all that) and gearotica has been a godsend.    Part of the nature of these clocks is gears with high tooth counts (a 224 tooth gear meshing with a 25 tooth gear is not that unusual),  long gear trains of up to 10 gears, and slow movements .

I thought I would start off with the "why" behind my feature requests and try an put them in the easy to impossibl e order.

1.   Gears with high tooth counts display on the project screen with odd shaped teeth that don't really even mesh.   Easy to see, just make a 225 and 25 tooth gears with a pitch of 15 and a pressure angle of 20 (that's my standard for these things) and create them on the project screen.   I remember something that to generate this many teeth would be too slow, but maybe it could be configura ble.   The gears convert to DXF just fine and have the proper teeth once I cut them so it's more of an display issue than anything.   I don't need anything to rotate quickly if that is a problem.

2.   Often the master gear has the high tooth count (things are based on the sun, with things moving around it) and the master needs to move very slowly.   Even the 1 RPM is way too fast.  Could we have a granny gear (pun intended) for doing the rotation?   Like .1 speed.   I can use the step function, but to see them rotate is even better.

3.   With these long gear trains, being able to name the shafts would be a help.

4.  And something I have asked about before, is being able to move gears after the fact.   I pondered your response about how would this work and have an idea.   What if you could "lock" gears in place and the others drag around it.    The problem I have is I need the final gear in a train to end up in a specific spot,  this takes quite a bit of jiggering when it's six or nine gears in a train and seven gear trains.   This may be impossibl e feature to implement, but if you could lock the starting gear and tug on the last one it would go straight.   Or lock a couple gears down the train and you could pull the end one to where you want it.

5.  And finally, how about having multiple plates?    Again, with these multiple trains I end up having 4 or 5 levels of gears, I have to build spreadshe ets to help me keep track of which shaft goes through which plate.  This relates back to item 3.   Right now I just widely space out my gears and I can visually tell where they should go.

From a practical standpoin t, will this allow you to insert gears in a train, or perhaps move a shaft ever so slightly and not have to replace all the gears from that point on?

Crossing my fingers that the answer is yes....

Thanks

Kevin

Is that something that can be changed on the fly and somehow regenerat e an entire project?

As a data point, I use .007 inches when cutting wooden gears out of MDF and that works pretty well for me.   I use a pitch of 15 so they are a little bigger than the ones you cut.

Sometimes I have to delete a train of 3 or 4 gears as the final ones do not line up properly.   Right now I make note of all the "placement angles" that I choose and when I re-create a train, I can rebuilt it.

In other words, in a A-B-C-D train, I might have chosen a placement angle of 180 degrees for B, but then D is in the wrong place by the time I get there.   So I go back and move B to a 179 degree angle and start over.   As often as not, there could be a time span in there and I've misplaced the notes I made and I am not sure what placement angle I used.   I can get pretty close with the old parm's file, but the angle in there makes no sense to me.  "Angle: 1061.91" is what it has for a gear I had a 180 degree placement angle with.

I hope this makes sense and the info is in there somewhere ...

Sounds like we have similar setup.  A inside computer where I actually do my gearotic work.   A "shop laptop" for quick fixes with a copy of the CAM program, and a Mach 3 computer also out in the shop.   

As long as all are networked, what works great for me is a free service called "dropbox".  (At least the first 5Gb is free, you have to pay if you store more than that).  It puts a special folder that it keeps in sync with all machines.   The files are actually local, so you don't have to worry about running gcode off a network drive.   There is even a little icon next to the file that tells you if the file is in "sync" or not.

Even though the Mach 3 computer is in the shop, which is 20 yards from the house, I have one of those usb wireless boxes and it gets a pretty good signal from the wireless in the house.   Apart from the wireless and mach3, there is nothing else on the computer.

I'm using .0625 bit's running at 20K rpm with speeds set to 70ipm.   I don't get that in real life with all the twists and turns, but the DRO does show me in the mid 30's most of the time.   I haven't broken a bit yet.   

I cannot tell much differenc e between my router cuts and my dad's high end laser engraver.   His is still faster as I have to go around a few times, but not by much.

I believe that was the issue.   All the axis were set with fairly low accel values (my Z was set to 1) as I was thinking that the only downside to a low value was it would take longer to cut.   I changed them all to roughly 20% of the speed.  (Speed at 80, accel set to 16).   I use timing belts to drive the axis so my thinking is I can tolerate a fairly high accel without too much shock.

Did a couple test gears and they seem much better.   I wish I had an optical comparato r or something, maybe I'll have one of the kids examine them as their eyes are much better than mine.

It's funny that the solution to both issues I've had with gear cutting was to "go faster".

I use SheetCam to do further layout of my gears (nesting and such).   I import the gears in DXF format and generally all is good.   For some smaller gears, where SheetCam uses arc's in the g-code, my tooth profile doesn't cut correctly .   (see photo).   The teeth look correct in the toolpath in both SheetCam and in Mach3.    This is highly repeatabl e, the same gear will cut the same tooth incorrect ly in the same way over and over.

If I tell SheetCam to not use arcs (G3) I don't seem to have this issue.   I was thinking it's a SheetCam issue, but I talked with Les and he pointed out that the tool path's w/o arc's and with arc's show up exactly the same in Mach3.   Am posting my gcode in the hopes that this looks familiar to someone.. .

I don't think it's my setup as I've cut hundreds of gears and it only happens on a select few.   It's repeatabl e, if I make 10 passes on the same gear it cuts it exactly the same every time.   Using Gearotic 4.5, Mach R3.04.037 and SheetCam 4.1.1.