Clamps and holding fixtures

[Greenworks Tooling]

Hello all,  

Small shop, just got a seat at the table, and haven't had the chance to attend a formal training session yet.  Hit the ground running right!lol

I did a search on clamps and fixtures, but the results were overwhelming, and pretty specific.  I'm looking for general practices that most folks here use to avoid clamps and fixtures in 3 axis milling?  Do most of you just use a containment boundary, or can you actually represent clamps on your model somehow?  I've seen youtube videos where people have vices and clamps are represented.  That's trick, but I'm not sure how to do that?

[Ewood42]

Probably was not the best practice, but when I was at a job shop I modeled (more often imported models) of everything if I was worried about clearance then drew boundaries around them. Drawing a wire frame boundary is often sufficient though if you are confident on the actual size/shape/location of your clamps. There is (used to be anyway) a "tabs" feature in many toolpaths that was supposed to do this for you, but I always found it easier to just draw them.

I'm sure I'll be corrected as soon as someone with more than my paltry 6 years experience reads this though, just my 2 cents.

[jeff]

Yes the Tabs feature is in toolpaths like 2D contour. I've used it here and there over the years,but not enough to remember how to use it correctly without taking a long time to get it right. But it does work pretty good.

Usually I will just draw boundaries around my clamps to avoid them and then adjust my toolpath geometry to get what I want. OR I set my jump heights if drilling so they don't smash.

[crazy^millman]

I have solid models going back 20+ years for vices, clamps, bolts, fixtures and other things I pull from all the time. I have developed my folder into a tooling components folder with 48,702 files in 878 folders that is 3.87gb on my computer. I add models to it all the time and each manufacture at this point has their own folder, but I have expanded it to solids of holders and not just fixture stuff. I am a contractor programmer and I keep food on my table by going the extra mile and modeling vices, clamps and fixtures for all the operation. I define each holder and then give tool list and setup sheets for each operation. Difference is someone else whom most times I have never met are running my programs. You are running your own work then you got a lot of lea way on what you can get away with, but even when I run my own work I know what I know by taking the time to know what I know for each program I make. Yes it may seem like overkill, but when you can go back to work and pick it up real quick because you took that time to be able to know what you know then you see why it is good to know by taking some extra time to do it right.

Here is what my subfolders look like in that directory.

[Greenworks Tooling]

2 hours ago, jeff said:

Yes the Tabs feature is in toolpaths like 2D contour. I've used it here and there over the years,but not enough to remember how to use it correctly without taking a long time to get it right. But it does work pretty good.

Usually I will just draw boundaries around my clamps to avoid them and then adjust my toolpath geometry to get what I want. OR I set my jump heights if drilling so they don't smash.

I've used tabs before, but for making tabs

I usually machine layup molds for aircraft.  I've got a removable part that pins to the parent mold that's kind of free form.  No flats anywhere.  Ordering a block that's bigger, so I can use tabs to hold it in space while I clamp to the parameter of the block. Kinda like the parts were held in your old revell model sets, but 25 inches by 10 by 3.lol

[Matthew Hajicek - Singularity]

Putting in the models help make clearer setup sheets too.

 

TEST BLOCK CHAMFER.PDF

[RaiderX]

Tool shop here

doing a lot of layup molds, hand router fixtures, layup masters and all details in between so the spectrum all over as far as size and configuration.

I have a plate that lives on one of my machines with 1 inch space 1/2 tapped for bolts. I try to order stock oversize to bolt thru and tab off whenever possible I HATE CLAMPS my setup guy or programmer always try to run over them no matter how carefull (I am the programmer, setup and machinist lol).

one guy and three machines 3-5 axis I have to run unattended whenever I can so any obstacle in the way is just getting closer to a bad day.

[Greenworks Tooling]

It's just me doing this, so I have the latitude to not make setup sheets, and I can run back and forth between computer and machine modifying things on the fly.  I'll need to get some processes down here soon.  I can't do this on my own forever.  Bout to lose my mind right now.  I've got a block of aluminum sitting on the mill.  Just sitting there!  Needs setup, but I can't program and setup at the same time.  

[Greenworks Tooling]

17 hours ago, Matthew Hajicek™ - Conventus said:

Putting in the models help make clearer setup sheets too.

 

TEST BLOCK CHAMFER.PDF

That's bad a** man.  Hope to get there.  I'm wearing too many hats right now though.  If Dad and I hadn't invested so much in the machines I think I'd be happy just being a programmer.

[RaiderX]

26 minutes ago, Greenworks Tooling said:

It's just me doing this, so I have the latitude to not make setup sheets, and I can run back and forth between computer and machine modifying things on the fly.  I'll need to get some processes down here soon.  I can't do this on my own forever.  Bout to lose my mind right now.  I've got a block of aluminum sitting on the mill.  Just sitting there!  Needs setup, but I can't program and setup at the same time.  

I feel you but its not a bad place to be in. you can set it up how it works best for you.

dont do like me and start out not documenting at least in mastercam how you did it. got bit a few times several months down the road they wanted me to make a repeat tool, was running so fast took me a bit of time to figure out my own mess. lol

i have a set of dedicated cutters in each machine with mcam tool library in detail.

also as mentioned fixtures are all standardized and modeled. 

pull it in and gram it, makes life so much easier. can dang near set my machine work offsets from mastercam seat. I usually calculate from know point on the machine dont even have to pick it up or touch off tools.