Here we go again . . . MK4

[routercnc]

Mini update -

Cut out the 3rd bracing piece:


Final one under way:


All 4 profile ops done:


Then onto the side ops. I need to machine several side features starting with 2off 6.8 pilot holes (to later take an M8 thread). Bit nervous as I'm trialling fusion 360 for the first time as it can do these pilot holes as spiral bores. Done a few aircuts and all seems OK from a cutting point of view (apart from that G28 as mentioned in another post).

Here is the fixture:


Luckily I had planned ahead (!?) and the first triangular brace I made with the poor surface finish could be used as a support. It will be sacrificial as one of the ops will cut into it.
The vertical angle is held by the precision vice, with a backstop at one end. The part just drops in and is then clamped. I was just about to hit cycle start and I was called away ! So it will have to wait . . . .

[routercnc]

I've been busy with other projects but back on it again and ready for some updates. I've had to re-read the last few posts so see where I'd left off so apologies if I repeat something.
Last time I left you in suspense over the holes in the side of the bracing pieces. Here they are being machined:


All 4 pieces machined:


Two of the holes need to be M8 tapped, and one is a clearance + counterbore. Here is the counterbore being done.


Bit nerve racking for 2 reasons. Firstly the pilot hole was machined blind on the other side, so I had to hope I'd got it all lined up so that the counterbore appeared in line with the hole. As you can see it was all OK:


Secondly, part was a bit close to the chuck. I'd measured it and knew it would clear. Clearance is clearance as they say but still glad it went OK. . . .


Then tapping the M8 holes on the bottom:


All 4 parts done:


_____________________________
Then back to the side panels. They needed holes on the sides which is always a bit more awkward. Got them dialled in:



Machined the holes and noticed that the top edge had a slight climb to it across the width with one edge 0.05 higher than the other. I guess this is reaching the limit of my current machine when cutting out a profile. So I took a very light skim to get it square again. This needs to be square to make the whole box square:


Repeated for the other one, then placed them machined edge side down onto an assumed good reference surface (lathe cross slide) to get them level with each other and then clamped them together:


Then machined the other edge, by taking a minute skim off, and then machined out the holes:


Then tapped the M8 holes:


Final dry fit of everything:


More to follow . . .

[routercnc]

The tram plates also needed holes in the side. Here was the set up:


These holes needed to go all the way through the part, which is quite wide. The cnc machine can bore about 20mm into the hole, so the rest would need to be drilled out. But I didn't trust the drill not to wander so machined the bores on BOTH sides of the part using this fixture. Then drilled it out on the pillar drill from both sides until it met roughly in the middle. Guaranteed to get a straight hole !


Then counter-bored to hide the cap head and cleaned up:


_________________________________

Onto the Z stepper mounting plate, which will hold to the 2 stepper motors. First time using Fusion360 so a bit worried about how it would turn out (didn't need to worry as it turned out and have not looked back). Exported the part as an IGES file from my CAD programme and used F360 for the CAM. Very impressed with it. Here is the part to be machined:


As you can see I was still using a profile method to cut it out (hangup of using Vectric Cut2D), but have since learnt much better methods.

Holes:


Profile:


Stepper holes drilled and tapped, and done:


More to follow . . .

[routercnc]

Next up was a little job I'd been putting off until I'd got to grips with F360. These are going to be inserts which fit inside the extrusion to connect the bed uprights. I'm sure there are many ways to make these parts but I decided to get some practice on adaptive tool paths. Here is the first of 16 parts:


It all started with a large 8mm sheet:


I then machined 2 edges so that the parts would be the right length:


Then over to the chop saw to rough them out to width:




Next part tool a while - machining the 3rd edge on each part in turn:


Not sure if this is good practice or not but the 4th edge I did in small batches:


All to size . . .


Then 6.8 mm holes machined (ready for M8 tap):


Now onto the angled sides. I made a fixture to hold the parts which had 2 datums for alignment:




The fixture was dropped into the vice each time and aligned in Y (fore/aft) by eye as this is not critical. It only needed to hold the blank in the correct X (left to right) and Z (up and down) position.

Then a 2D adaptive to rough it out. I had intended to do a cleanup but this doubled the machining time and the parts fitted fine with just the roughing:


The adaptive took about 2.5 minutes which was not too bad. I've done 8 parts, 8 to go . . .

[Clive S]

Nice work following with interest

[Nr1madman]

It's mechanical porno!! ;)

[routercnc]

Cheers guys. It's very satisfying when it all works so glad you are enjoying it too.
For anyone thinking about jumping to F360 then I'd say don't hesitate. Its a powerful bit of software and is daunting at first but start simple and go from there.