Converting an AMAT25LV

[Davek0974]

Ok, got it, makes sense now.

I think you did the right thing, my BP can fling the chips a good 8' away but its only me so who cares :)

I was strongly advised NOT to convert the BP and that advice was right. The advise was to sell it and get an old CNC VMC etc and retrofit the electrics - this would have been ideal BUT i could not physically fit anything but a BP in my shop - not even a proper CNC BP. I also do not have the power capacity for the big spindle motors on CNC stuff.

Now i have used it a few times, I REALLY want a proper CNC mill with an auto tool changer. ;)

Total cost was silly money but once you dive in you cant back out.

[Lloyd Barnes]

Well, its about ready to go. I've taken the advice and setup the Z Axis with a 2:1 belt drive (very annoyingly I ordered the wrong belt length so just waiting now for the right one to come). Most of the rest of it is complete so once the belt is here its time to take a few trial cuts and see where it is. Y Axis NEMA23 with spindly legs is now mercifully covered up, cover plate for the X Axis next. Hopefully starting to cut some trial parts this weekend.
/p
Appreciate all the advice so far

[Davek0974]

Looking good :)

[Lloyd Barnes]

Well chaps, she runs like a good un! Many thanks for the advice. The Z NEMA34 motor didn't work with 48V and direct drive as you suspected, was losing steps. Switched it out to a 2:1 belt drive and all sorted.
P
Got Mach3 licenced today and ran a quick test part. Few screw ups here and there, didn't get the CAM quite right (Fusion 360) so the pocket bottoms didn't clean up, and like an idiot I managed to run the spindle in reverse for the first part of the chamfer op so that's a bit messy in parts, but that's just me being an idiot and easily fixed next time.
P
The machine itself I'm generally pleased with. It ran the part in around 40 minutes, and with fresh end mills that are a little sharper I'm pretty sure I can be a bit more aggressive if I needed to be. Dimensionally it seems to be cutting to around 0.1 to 0.075mm accuracy which I'm hoping I can improve by tweaking the jam nuts on the ballscrews to take out any backlash etc. What sort of accuracy do you think its practical to get on a small machine like this? 0.1mm would be fine for many of my parts I'll be making, some however I'd need a little better, for example where I'm after a sliding or press fit between two parts. I didn't put a lot of time into this part, it was more to get myself going on the basics so I'm sure with time I can improve.
P
Doubtless I'll have more dumb questions as I get the mill dialled in. For now though I'm planning on getting my tool library setup and sorted out in Fusion and get some parts through to get more comfortable with the CAM in particular. I'm still at the stage with Fusion CAM where I'm not 100% sure what I'm doing, particularly selecting the geometry to get it to do what I'm after but I'm sure it will get easier. Once again, thanks for the advice and encouragement. Much appreciated.
P

[Lloyd Barnes]

B8gger, I knew I had another question. I want to get myself a decent flycutter. I'm not good at grinding tooling, would prefer one with an indexable tip. I like the results the Tormach Superfly Cutter seems to get but are there any UK based similar tools? Or has anyone put an indexable lathe tool in a normal flycutter body and got good results?

[Lloyd Barnes]

Slowly getting there.
p
Thought I'd make a tooling holder as a practice project. Haven't quite got the hang of the settings in Fusion 360 for chamfering yet, plus when I had Mach3 in feed hold and was restarting it did a preparatory move and milled a channel right across the piece (under my thumb in first pic) .
p
Fortunately I'm making 2 of them so this one can be the one at the bottom if I can get the second one bang on!
p

[routercnc]

Hi Lloyd,

There are lots of examples of indexable lathe tools being used in home made flycutters. Here is one:
https://www.youtube.com/watch?v=QgvbVLfeig8

This Old Tony made one using high speed steel tools:
https://www.youtube.com/watch?v=JBDNu_ViHlU

I haven't used any of these as my WC spindle is too fast and the interrupted cut is a bit hard on the bearings. However, Arceurotrade have started selling these micro flycutters which look tempting and are low cost:
http://www.arceurotrade.co.uk/Catalo...Straight-Shank

As for the mess ups, this is how it goes when you start off. There is a list of them and you just have to work your way down them ticking them off and not doing them again. You are getting stuck in and the parts are looking good !

Edit: The preparatory move after a feed hold - was that using the 'run from here' button? I don't know if I'm doing this right but I've found that this moves the tool diagonally (across AND down) from where you are to where the cut wants to start. This can go through the work piece, clamps etc. So I always go to the prep move page which shows where it wants to move to in X and Y, then cancel out of that window and MDI the machine to that X Y position, then do run from here again with the spindle on. It then just goes straight down onto the cut and waits for you to hit cycle start to carry on the cut.