Newbie looking at 6040 (China CNC) for polypropylene 15mm sheet

Because you are using 6mm cutters from memory, I filmed a very simple job I did a day ago producing some slots. 3 Flute High Helix 6 mm Dim 6.7 wide slot, the difference is this cutter is not a ripper as you are using for roughing out, It would be considerably faster with a ripper but for this job it worked as it was.

One of the examples of this is how important coolant is and you can see what we do in industry, especially in closed slots like this where there isnt a lot of room for swarf

It's not fast and the speeds can be ramped up a fair bit if needs be, but it was adequate for the job in had without any risks. The time i had debured the previous part the one on the machine is done, so speed isnt always everything. My machine is not massively fast as its a solid way machine but that does have advantages also.


https://www.youtube.com/watch?v=RT6XYkOYJHwhttp://

https://www.youtube.com/watch?v=RT6XYkOYJHw

https://s17.postimg.cc/hioc02ci7/IM..._051007262.jpg

https://s17.postimg.cc/541jzqspr/IM..._051008808.jpg

https://s17.postimg.cc/7y4pd7abj/IM..._051320248.jpg

https://s17.postimg.cc/bhqn305bj/IM..._051329842.jpg


Slippage...

https://media.licdn.com/mpr/mpr/AAEA...MjViYjQ4YQ.jpg

Just a note on the 8mm drill bit these spindles really don't like spinning slow enough and the framework isn't strong enough you will dull bits faster than you can blink. 6.5mm is ok for predrilling.

Still having problems with accuracy.

I have my custom vice jaws that hold my case parts. I use the probe to touch off for origin.
I then run a small test cut to double check and it is usually 0.1-0.2mm out in Y.
I then test again and looks fine.

Remove part from vice and replace with same part, and for some reason the X is now out by quite a bit. 0.3-0.5mm from the looks of it.
I know the vice clamping down on the part does make it bend slightly. But I am only going finger tight to reduce this.

Any ideas?

Literally the last operation on the part to chamfer it. I would do it by hand if I could but I also have to drill holes for bolt heads.

Quote:

---

Originally Posted by JOGARA

Still having problems with accuracy.

I have my custom vice jaws that hold my case parts. I use the probe to touch off for origin.
I then run a small test cut to double check and it is usually 0.1-0.2mm out in Y.
I then test again and looks fine.

Remove part from vice and replace with same part, and for some reason the X is now out by quite a bit. 0.3-0.5mm from the looks of it.
I know the vice clamping down on the part does make it bend slightly. But I am only going finger tight to reduce this.

Any ideas?

Literally the last operation on the part to chamfer it. I would do it by hand if I could but I also have to drill holes for bolt heads.

---

You're using a drill vice, you're never going to get repeatability out of it, 0.1-0.3 isn't bad considering. They don't close evenly, the jaws don't shut parallel, they push the work up when they close and as you've mentioned because your part is thin it's susceptible to bending.

As I mentioned before, a jig plate would be a far more suitable fixture for the 2nd setup. Once made it would be much quicker to set up and a lot more accurate and repeatable.

Quote:

---

Originally Posted by Snapper

You're using a drill vice, you're never going to get repeatability out of it, 0.1-0.3 isn't bad considering. They don't close evenly, the jaws don't shut parallel, they push the work up when they close and as you've mentioned because your part is thin it's susceptible to bending.

As I mentioned before, a jig plate would be a far more suitable fixture for the 2nd setup. Once made it would be much quicker to set up and a lot more accurate and repeatable.

---

No idea where to start creating a jig plate for these cases.

Quote:

---

Originally Posted by JOGARA

No idea where to start creating a jig plate for these cases.

---

If it's specific for one part then your imagination is the limit. You just need a method to quickly and accurately place the part on the jig, some sort of reference to touch off, and a way to hold it. As a couple of examples, if you have holes or can find somewhere to put extra holes for dowels on what will be the bottom face that's a really easy and accurate way to do it. You could cut a pocket in the plate for the part to sit in. Could even just have a straight edge in each X and Y to butt the part up against. And just a way to hold it down, step clamps, bolts directly through any through holes etc.

The amount of time this could save you compared to flipping and touching off each part in the vice for every single op could be substantial, leaving you only needing to set up for each op once at the start of the day. So you'd use some sort of reference in your vice to line stock up with and cut so many parts from one side in the vice, then set up once on the jig plate and do all the flip side. If you see what I mean. Save your work offsets for your vice and jig work as G54 and G55 then when you start your machine the next day all you have to do is chuck up your edge finder/probe or whatever you use and make tiny adjustments to account for the error in the home switches at the start of the day.

For batch work on a machine like this with the tools you have I can't think of a better way to do it.

Quote:

---

Originally Posted by Snapper

If it's specific for one part then your imagination is the limit. You just need a method to quickly and accurately place the part on the jig, some sort of reference to touch off, and a way to hold it. As a couple of examples, if you have holes or can find somewhere to put extra holes for dowels on what will be the bottom face that's a really easy and accurate way to do it. You could cut a pocket in the plate for the part to sit in. Could even just have a straight edge in each X and Y to butt the part up against. And just a way to hold it down, step clamps, bolts directly through any through holes etc.

The amount of time this could save you compared to flipping and touching off each part in the vice for every single op could be substantial, leaving you only needing to set up for each op once at the start of the day. So you'd use some sort of reference in your vice to line stock up with and cut so many parts from one side in the vice, then set up once on the jig plate and do all the flip side. If you see what I mean. Save your work offsets for your vice and jig work as G54 and G55 then when you start your machine the next day all you have to do is chuck up your edge finder/probe or whatever you use and make tiny adjustments to account for the error in the home switches at the start of the day.

For batch work on a machine like this with the tools you have I can't think of a better way to do it.

---

Or get a propper machine vice? :p


What I can't work out with my part is how to clamp it down with a jig.
The part I want to chamfer are the outer edges and then the button holes and bolt holes.
If I was to hold the part using any of these, I add time to my operation.

I am thinking just get a decent vice that is meant to CNC and make my soft jaws for it.
They work well as work holding though obviously, I do have a slight bend in the material due to the design.
Not helping myself atm holding the part lengthways instead of widthways.

Yeah, you'd clamp from say the external and do all the internal chamfers then clamp from inside to do the external. Moving a couple of bolts and clamps is measured in seconds, compared to chucking up and adjusting your probe if you're finding need for it. And it reduces or entirely negates the chances of twisting your piece. You might also find that you're taking so much meat out of the part in the first op that the vice is distorting the work anyway once it's cut down so much.

Just a suggestion anyway and something to think about.

What about a tooling plate and edge clamps?

https://www.google.co.uk/search?q=mi...w=1278&bih=660

The only way I can think of doing it is to get a bit of 15mm and have my part sit in it.
Then when the vice clamps down, the slight bend in the aluminum locks that part in place. I am talking a tiny tolerance that will not bend enough to cause problems, but enough to grip onto the part.

I'd model it up but my laptop has crapped out on me. Thanks, Windows.


Also, looking to add a solenoid valve to the machine to turn the air on and off.
Fed up with having to reach in and turn it on and off. That and I run the machine and leave it for a bit. If it errors our or finishes the op before Ig et back, would rather it switch off the air.
12v is what the X6-2200L uses on control board right?

Here is my idea.

Block with the case silhouette cut out of it. When the vice clamps down there should be a slight bend in the block resulting in it clamping the part.

https://s10.postimg.cc/vgyrmgu95/image.png

https://s10.postimg.cc/zdc3igmyh/image.png

Still relying on your vice...

Make that piece (except minus those channels you added to allow it to flex inwards) out of something nice and sturdy - either alu or something like SRBP. Add a couple of threaded holes either side to allow clamps to hold it externally, and maybe two threaded holes internally underneath those cut outs. I would also add a zero reference hole (the probe works better determining zero from a hole probe than from an open edge probe), though I would ream it rather than just drill/mill it.

That then allows you to clamp internally with just a screw and spacer, run your external ops, then switch over to clamping externally with screws and a clamp piece to run your internal ops. Only takes a minute to undo two screws and screw in the other set for switching from internal to external.

depending on what you are doing operations wise, you can also consider the external clamping from both the ends and the sides to allow you to run different operations with external clamping but it doesn't sound like you'll need to.

I am tempted just to buy a decent machine vice and do it properly..

I think it is obvious that I need a better one anyway when I am doing my first op.
I got to make this easier as I have 30-50 cases to make of each type.

The X6-2200L has 140mm height between the floor and the gantry.
Minus ~5mm for a spoilplate/wonky correction.
Leaves me with 135mm.


Been looking at this, http://www.ymttooling.co.uk/tuscan-s...hine-vice.html
117.5mm to the top of the jaws.
Even if I was to hold parts at the top of the jaws, that is 17.5mm clearance.
The reason I like this vice is that I could probably make the soft jaws really easily.
The lower height ones I have seen all have the triangle jaws which I can't manufacture.
They do sell soft jaws for this but they are £86...

This style of vice is lower - https://www.cutwel.co.uk/work-holdin...-machine-vices
However I've still to find more reasonably priced version.

Quote:

---

Originally Posted by m_c

This style of vice is lower - https://www.cutwel.co.uk/work-holdin...-machine-vices
However I've still to find more reasonably priced version.

---

I checked them out as like you say they are lower. But they are costly and I can't make my own soft jaws for them

It seems to the ideal vice for what I'd like, but I'm holding of in the hope Cutwel have a promo on them at some point, or until I find something similar in a 5-6" jaw version.

You can make anything with the right tools ;-)

Quote:

---

Originally Posted by m_c

It seems to the ideal vice for what I'd like, but I'm holding of in the hope Cutwel have a promo on them at some point

---

Give Cutwell a ring they will give you good deal. (ask for Harriot Dootson)

Cutwel had the Gerardi vices on offer in December, I got one. Wish I'd got two. Or thee. Or four :sulkiness:

You can set the Gerardi vice up how you want, it doesn't need to have the angle jaws, you can get them with flat jaws, serrated jaws or whatever you want. It's a modular vice and there's a whole tonne of accesories for them. You've still got the issue of the vice bending your work, and in the case of the Gerardi the angle jaws would cause it to bend quite badly (the angle is there to add downforce for pulling the work down to ensure it clamps true repeatedly).

A dedicated fixture really is the way to go here IMO.

What model of those extrusion channel nuts do I need for this X6-2200L?

Quote:

---

Originally Posted by JOGARA

What model of those extrusion channel nuts do I need for this X6-2200L?

---

I can't remember, I had a new solid bed made for mine, I think they were 8mm. Get m6 or even m5 if you like. KJN sell them, but they charge an arm and a leg for delivery if you're not nearby.

Ordered that vice and a new plate for leveling it.

https://s10.postimg.cc/k2tg2g83t/Capture.png
Just saw this on FaceBook. No idea why I haven't seen this idea posted around before. Would have saved hours.
Will be testing it with this new vice.

Wait. Could have just printed a holder for the part and mounted it onto the base of the cnc machine....
Well at least the new vice will be a good paper weight...

Quote:

---

Originally Posted by Snapper

I can't remember, I had a new solid bed made for mine, I think they were 8mm. Get m6 or even m5 if you like. KJN sell them, but they charge an arm and a leg for delivery if you're not nearby.

---

Thanks.
I have emailed them to see if they can confirm what size.
The gap at the top is 8.5mm and the OD of the threads is 7mm.
Can't pull them out atm as the machine is running.

You do realise those MarkForged jaws aren't plastic?
MarkForged produce carbon fiber and metal 3D printers.


I never seen the Gerardi vice offer :-/
I'll give Cutwel a call once I'm feeling a bit more flush, as I could really do with behaving for a couple months to let finances recover from last years expenses.

Quote:

---

Originally Posted by m_c

You do realise those MarkForged jaws aren't plastic?
MarkForged produce carbon fiber and metal 3D printers.


I never seen the Gerardi vice offer :-/
I'll give Cutwel a call once I'm feeling a bit more flush, as I could really do with behaving for a couple months to let finances recover from last years expenses.

---

I print PLA 'Carbon fiber' xD

I don't actually mean to use them, just test fit before making aluminium ones..
But even so, would be fine if it was a large block that you sit the part in for chamfer operation?

I would think so for chamfering.

I'm not sure I'd trust them for anything involving much higher cutting forces though, but there is only way to find out..

Quote:

---

Originally Posted by m_c

I would think so for chamfering.

I'm not sure I'd trust them for anything involving much higher cutting forces though, but there is only way to find out..

---

Might give it a go. Would make a nice little YouTube video.

Bit of Googlering and a few people are saying that it is M8 that one wants.

Yea shipping on KJN.


RS does some extrusion stuff though, these look about right?
https://uk.rs-online.com/web/p/conne...nents/3900379/

Quote:

---

Originally Posted by JOGARA

Bit of Googlering and a few people are saying that it is M8 that one wants.

Yea shipping on KJN.


RS does some extrusion stuff though, these look about right?
https://uk.rs-online.com/web/p/conne...nents/3900379/

---

You don't want m8. You will constantly be fighting to get the bolts through the slots and threaded in the nuts and there is absolutely no need for that much clamping force. M4 or m5 will be just as good, I used m6 because I have a tonne of m6 fixings in all sizes which is important. If you use rs the ones linked or these are the ones you want but not in m8.

https://uk.rs-online.com/mobile/p/co...nents/3900256/

You also don't want to be thinking about using anything 3D printed if accuracy and repeatability is what you're after.

Just a thought here which I should have thought of sooner. You are aware of the sheer weight of a proper machine vice? I don't think the flimsy hollow extruded aluminium table that comes on the OMIO will give you much improved results. The bed will dip and probably bounce around like a trampoline. Think about that and try some tests before you actually use the vice and can no longer return it.

Quote:

---

Originally Posted by Snapper

Just a thought here which I should have thought of sooner. You are aware of the sheer weight of a proper machine vice? I don't think the flimsy hollow extruded aluminium table that comes on the OMIO will give you much improved results. The bed will dip and probably bounce around like a trampoline. Think about that and try some tests before you actually use the vice and can no longer return it.

---

Had that thought to. Trying to have it close to the vertical frame.
Should have just bought a Tormach...

Dam this thing is large. What have I done... xD


[edit]

My bed is out by 0.5mm in some places :/

I have worked out how I am going to do it. Ill remove the old vice and center this one and get it all nice and level.
To hold my parts, as the top of the vice is so high up, I can just cheap and use a big sab of 15mm as my part spoil 'board' to mount it on like before, but it will sit deeper into the vice with 40-50mm either side of it to prevent the spindle crshing into it.

Quote:

---

Originally Posted by JOGARA

Dam this thing is large. What have I done... xD

---

Maybe puts into perspective how feeble the OMIO is in real terms and what you're wanting to make it do :courage:

Seriously, put some thought into a dedicated fixture and maybe save yourself a few hundred quid in the process. That big hefty unit is a firm sledgehammer to crack a walnut sort of job.

Plate done and vice mounted.

https://s10.postimg.cc/3w38gls95/IM..._164413977.jpg

https://s10.postimg.cc/eix1m1849/IM...456060_HDR.jpg

https://s10.postimg.cc/cecokxjc9/IM...118256_HDR.jpg

https://s10.postimg.cc/f8ftyegdl/IM...122827_HDR.jpg

Yes, I could do with larger OD washers. These were all that Screwfix had and the Fixings store I normally go to is now miles away as we moved. That and he closes early xD
The M8 extrustion T-nuts from RS are fine. The bolt is hard to start threading into them but once you have it they really do help.
I think the M6 would have been a bit to small as that would have meant smaller washer too. These things are not going to move.

Z is 0.2mm high at one side of the vice on the Y-axis. X-axis there is no difference.
The Y-axis measurement was taken 350mm from the back of the vice to the front. Most of my parts are sub 100mm so that should be more than fine?

The vice is square or within measurable tolerance with the probe and dial indicator.



It also looks dank af... I get points for that no?

Quote:

---

Z is 0.2mm high at one side of the vice on the Y-axis. X-axis there is no difference.

---

You could shim the vice level

Quote:

---

Originally Posted by Clive S

You could shim the vice level

---

If I touch this again it will never be better xD

Dam it. I forgot that I have an operation where I need to stand the 105mm tall part on its end to mill out connector holes...

I do have a tiny vice that I could use for this. Might be able to fit it in behind the new vice, will be hard to reach but really is it my only option :/

Great way to firm up the 6040 bed. . . . . . .Replace virtually the entire bed with an enormous vice!

I think it looks good. :smile:

How true is AW's "flat bar" stock?

Like do I need to order the size up of what I want to make it true over 150-200mm lenth of cut?

Best to buy bigger stock, hold on a few mm and do as much as you can on the first op then turn over and take the back off. The flat Ali bar won't be square so will cause more problems later if you don't square it up. Don't buy from aw either find a big metal supplier like smiths metal centres, it will work out a lot cheaper.

Quote:

---

Originally Posted by jamesgates1000

Best to buy bigger stock, hold on a few mm and do as much as you can on the first op then turn over and take the back off. The flat Ali bar won't be square so will cause more problems later if you don't square it up. Don't buy from aw either find a big metal supplier like smiths metal centres, it will work out a lot cheaper.

---

The stuff I was looing at would allow 5mm to be shaved off each side actually (made my part smaller).
Ill contact a few local companies. I have been using AW just for ease. But I have spent nearly £200 this past week which probably would have been a lot less locally xD