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

[JOGARA]

Yep, didnt get any response. No problem.

The STLs you provided were out of scale too, they dont translate to workable CAD parts. They can be converted but Fusion refused. Its better (for future) to export to something other than STL if possible (Step / IGES etc).

Yea all the people sending me messages said that.
Though they print fine on my 3D printer exporting that way..??



[edit]
Whats with the off center ring on these collect nuts btw?
I have seen it on both this new ball bearing one and my current one shipped with the machine.

[Clive S]

[edit]
Whats with the off center ring on these collect nuts btw?
I have seen it on both this new ball bearing one and my current one shipped with the machine.

That is to hold the collet in place. You have to wiggle the collet in there. I take it you have been doing this, as this might have been your problem.

[Chaz]

Yea all the people sending me messages said that.
Though they print fine on my 3D printer exporting that way..??



[edit]
Whats with the off center ring on these collect nuts btw?
I have seen it on both this new ball bearing one and my current one shipped with the machine.

I suspect its the way that our CAD systems are 'interpreting' the STL. I know there are some attributes that you can change when you import but not knowing the 'source', we may not know these and this means that the outputted assumption is wrong.

The fact that I wasnt the only person that said this means that there is something not 100%.

What do you use the make the STL?

[m_c]

That is to hold the collet in place. You have to wiggle the collet in there. I take it you have been doing this, as this might have been your problem.

It's actually to extract the collet from the holder. If you don't clip the collet past the offset lip, then the nut doesn't pull the collet back out when slackened, which can leave you with quite a big headache. Off course not clipping it in also causes uneven clamping, which can lead to excess runout and things not being as secure as they could be...

[Clive S]

It's actually to extract the collet from the holder. If you don't clip the collet past the offset lip, then the nut doesn't pull the collet back out when slackened, which can leave you with quite a big headache. Off course not clipping it in also causes uneven clamping, which can lead to excess runout and things not being as secure as they could be...

Of course you are correct My bad.

[JOGARA]

I suspect its the way that our CAD systems are 'interpreting' the STL. I know there are some attributes that you can change when you import but not knowing the 'source', we may not know these and this means that the outputted assumption is wrong.

The fact that I wasnt the only person that said this means that there is something not 100%.

What do you use the make the STL?

Exporting straight fro Fusion360 by right clicking my part and selecting "save as STL"






But why is it offset?
Wouldn't it also add vibration to the machine?

[m_c]

But why is it offset?
Wouldn't it also add vibration to the machine?

It's offset so you can get the collet in/out easily.
If it wasn't offset, you'd not be able to get the collet in/out easily, or you risk the collet popping out the nut when trying to remove the nut/cullet from the chuck.

Balanced nuts are available, if balance is an issue.

[JOGARA]

Trying to reduce the force that is pulling down the bit.

The thing I changed when it started to happen was that I went from 1mm DOC to 1.5mm DOC.
So I am changing that back (sadly the 1.5mm DOC halfs my machine time which is why I want it).

Wondering if the helix is also too much? It sounds nasty when it does it but that could be down to the machine rigidity?




I am tempted to grab a 8mm carbide drill bit and use that to get as far down as possible and use that hole as the "pre drill position"

[Chaz]

Exporting straight fro Fusion360 by right clicking my part and selecting "save as STL"






But why is it offset?
Wouldn't it also add vibration to the machine?

Not sure. Perhaps rather saving it as Fusion3D or similar.

[JOGARA]

Where can I get some oil or whatever to aid with cooling.

Reddit users said my setup for cooling was a bit shit and I have to agree. It is something I have not really looked at improving yet.
They also said my speeds and feeds were wrong for my 6mm roughing bit.

Apparently 12k is wayyyyyy to fast for my feed of 360mm so I am going to try in a bit with 6K and speeding up the feed slowly.

These two things will help resolve my issue.