Evening @Vince.Fab - question for you slightly commercially sensitive i guess so no pressure to answer, but one thing i have been interested in this thread are part failures. As in not during manufacture, more after being used on the cars do you have any that have not been able to handle the tolerances?
Do you see any at all or would you say you fall in line with other Major motor factors?
I love your work and you continue to inspire me to be more methodical in my work and ground myself in the knowledge that the SO£ is able to do this it is only limited to my ability to execute the commands lol
I have read this thread from top to bottom multiple times and love the content and your work. Thank you for the posts.
ONE QUESTION I have is where on earth did you get your 1" 1/4" shank index-able face mill? I have been searching in vain for days with no luck. Also what speeds and feeds are you running it at? I have a so3 standard with HDZ and a Saunders Machine Works aluminum bed and a dewalt router but soon I’m swapping to a 1.5kw 24k 110v spindle with steel core belts.
I’ve contacted them before about making custom tooling but they required a decent sized order. Also going to a 0.250 shank will make the tool less ridgid.
Thanks for reading! Its been a wild ride and this forum has been a huge help and inspiration.
Vince is right in the spindle. My Dewalt router spins really fast for it so I hesitate to use it much. A spindle or Makita router to be able to go 10,000 RPM would be preferable.
I have an er11 1.5kw spindle waiting on a custom shielded cable that is being made as we speak so swapping spindles is not an option at the moment. So I guess no 1" surfacing bits in my near future
They are inexpensive enough to purchase one and throw on a lathe and turn down. Even if there’s a little runnout it shouldn’t be a deal breaker for just surfacing.
So, dear @Vince.Fab, you have been, like to many others, an eye opener (weird to visualize lol) to aluminum cutting on SO3.
I am a fabricator for EV cars. I am currently doing a limited edition of a BMW 2002 with ver a trimmed tesla model s underbody.
Cutting aluminum parts were a necessity, so I started upgrading my so3 for that. First I changed to steel reinforced tracks (cables?), forgot the term.
Then upgraded my spindle.
However, once I went into big stock (2x6x24”) I ran i to issues where only being a snail would work.
I have an upgraded z axis with rails from cnc4newbie but in aluminum it had too much play (the rods would bend) and break my end mills and have a horrible finish.
Here are some pics of the finished suspension top mounts, with slow settings (took about a week to finish those two)
Now that I am getting some client work, I need to be faster and have better finishes, so I went a bit deeper the rabbit hole.
I have my aluminum atp-5 bed (which I’ll cut and drill tap myself) and currently doing the “shapeoko on rail” upgrade from @DanStory . I want to upgrade to ball screw but I want to do it right, upgraded motors, driver etc but this requires some time that I don’t have. I think I should be fine with those upgardes.
I also ordered the equivalent of the HDZ (which is out of stock) from cnc4newbie too.
Can’t wait to get all of this done!
Here are some pics of my ev bmw build:
Hello Dylan, fellow designer, fabricator and machinist! Thanks for posting your work and I’m sure its been an awesome experience integrating cnc into your workflow. Definitely keep us updated on your BMW EV project. Question. Have you ever welded a crash and reran toolpaths? Its an interesting spot to be in when you can tig and magic erase things.
Big Stock - A material where the thickness exceeds flute length. There’s a whole theory on part design, tooling, cam and workflow when it comes to big stock machining. When you are forced to use increased stickouts, its very helpful to use a force calculator like the @gmack
You also don’t have to go slow all the time, try separating the toolpath in half. Start with one that has the minimum stickout on the tool and maximum flutes and run it to max flute depth. The workbook will let you know the deflection and machine forces so run it hard. Then switch to a lower flute count tool with longer stickout to finish the bottom. For example, a single flute will minimize torque needed in the cut which will minimize machine forces and end mill deflection. That directly translates into surface quality, tool life, and chipload you can run. Finishing requires a light touch as well.
It looks like your part is lower than the stock height which means you could float it with tabs. Another way to look at making a tophat like that fast would be to use a vise with end stop or make a fixture plate with a corner reference. You could band saw your stock for a single part per piece workflow and perform a flip. This would allow you to run the most aggressively you could and machine all sides which both are benefits. Plus a repeatable setup helps if you ever run into problems.
Now don’t get me wrong, nobody loves upgrades more, and linear rails/spindles will help to some degree. But everything starts at feeds and speeds, and the move V wheels you have, the more it matters. Good call on the aluminum bed! Definitely get a vise and some consumable fixture plates setup on there. A nice little 3 jaw chuck can come in really handy as well.
Hi
Thank you for sharing that excel sheet, I will definitely use that.
No I have never tig welded a crash because I was always lucky enough for it to happen on an area that would be chipped off.
I have definitely found that feed and speed are most crucial. And yes, in that piece there was about 8 different operations. However I am not sure if it is a due to a bad batch, but my left side gantry plate (with v-wheels) never stays square to my right hand side. Not matter If I square the extrusions, realign and re-square the whole machine. When I home, 2/3 of the time my left side is about 1-3mm off. So after homing, I have to recheck squareness and bump the gantry to place it where it should be… I also upgraded the v-wheels, problem is still there.
Therefore I was thinking that the rails will prevent that to a certain extent, especially combined with aluminum bed.
Yes, you are right about the vise. I actually treated myself with two fixture plate and a small vise, pines and studs. I can’t wait to put everything together and see the improvements!
I had that problem on mine and it turned out to be one end of the X extrusion had not been cut square to the extrusion which twisted one of the Y plates out of plane. I cleaned up the cut as best I could without a milling machine and shimmed it until the X extrusion was square to both Y rails, then on my squared frame things worked a lot better.
I did about the same and I am still off. Maybe it will work fine once I have new plates made from atp5 plates
Griff
(Well crap, my hypometric precursor device is blown…)
745
Maybe try physically pushing the gantry against the back frame before engaging the steppers?
Early on in my always-learning SO3 experience I added this step to my workflow upon advice from, I believe, @WillAdams.
Since then I’ve managed to square up my machine pretty well but I still nail the gantry all the way back or all the way forward before I turn the controller on.
I really would get the stock machine consistent square before starting to do any upgrades. Not square extrusions will never be good until sorted. And if the frame isn’t square linear rails will bind easy.
Ok this might be a stupid question but I have to ask. I see several pictures that say they are videos but nothing happens when I click anywhere on them. How do I watch them?
Griff
(Well crap, my hypometric precursor device is blown…)
750
I believe Admins disabled Google-pasted in files. Sorry not up on IT speak. All I know is I can’t paste ‘em in anymore.
