Re: CNCRP 48x48 Pro for machining aluminum?
Quote:
Originally Posted by
infamous_panda
Thanks, I got tired of soaking my spoilboard with coolant and wd40. I used to have it set lower where I would not have to remove my vice when putting the spoilboard back. Unfortunately the long reach down causes some resonance and chatter issues on my machine, so I just screwed some blocks on the extrusion so I can reposition the vices repeatably in the same position.
Yeah, I like that idea as well. I was considering getting a ~1/2 - 1" thick aluminum plate made for the spoilboard and just drilling holes every inch or so, and then facing it. This would give me a nice base to mount parts to, and I could always attach a spoilboard to the top of that if I needed.
Re: CNCRP 48x48 Pro for machining aluminum?
Quote:
Originally Posted by
cowanrg
Those parts look good enough for me! That's about what I was looking to achieve, just with larger parts.
I see a lot of people using very shallow depth of cut, but it was always my understanding (and from experience) that shallow DOC gives you a poor surface finish because you're just using the very tip of the flutes and concentrating all the cutting forces on a small area. I would think using a 3/8" end mill with ~0.125" DOC would give better results, as long as you pay attention to your tool paths. Am I wrong here? I haven't really tried using one of course, but I see a lot of people aren't using a 'good' CAM program for their tool paths, just auto-generated stuff in aspire or whatever. For instance, 9 times out of 10, I see people just plunging the bit down and doing a slot rather than a helical plunge, or even a ramped slotting routine, etc.
I do for the most part .125 or .09 DOC at 80 imp, using 1/4 mills. I have also done full length 1” DOC super light 0.001 WOD finishing passes. I don’t do many repeat parts to be able to optimize the program. It’s better to have shallow DOC and WOD, and adjust the feed and rpm on the fly. Rigidity is what prevents me from going harder, there seems to be a lot of headroom on the 2.2kw spindle even at 12k rpm. I’d be curious of your result if you end up getting a newer pro4848
Re: CNCRP 48x48 Pro for machining aluminum?
Quote:
Originally Posted by
cowanrg
Yeah, I like that idea as well. I was considering getting a ~1/2 - 1" thick aluminum plate made for the spoilboard and just drilling holes every inch or so, and then facing it. This would give me a nice base to mount parts to, and I could always attach a spoilboard to the top of that if I needed.
That sounds like the right way to do it! I tend to do things on the cheap but functional
Re: CNCRP 48x48 Pro for machining aluminum?
Quote:
Originally Posted by
infamous_panda
That sounds like the right way to do it! I tend to do things on the cheap but functional
I was originally going to get a larger CNC vertical mill, so this is actually quite a bit cheaper, so I can throw a bit more money at it to get the most out of it.
Re: CNCRP 48x48 Pro for machining aluminum?
The end shows the finish.. This is 2 revisions of the pro4848 back. Much better now.
https://youtu.be/ovzT-3AAWIU
Re: CNCRP 48x48 Pro for machining aluminum?
Quote:
Originally Posted by
blitzer
I've seen that video and the results look promising. I was hoping for some personal accounts of people cutting aluminum (maybe with some 3d tool paths), but it looks like most people are just doing wood.
Re: CNCRP 48x48 Pro for machining aluminum?
I've cut 6061, 6063, hard naval brass, and just last week, stainless steel on my CRP PRO 4896. Much of those were done with a cheap ($1 per bit) 1/8" single flute up-spiral China carbide coated bit. You can get a fine polished finish on the inside and no burr if you get your feeds and speeds right. Use crappy bits when you're learning so you don't get upset when you grind down or snap an $80 end mill accidentally. My technique has been the same when I'm working with metals. I jig it up as flat and rigid as possible and squirt a low viscosity cutting fluid along the way after finding a good speed/feed combo. I've never taken off .125 per pass with any metal, but I'm often using small diameter bits. You CAN cut whatever you'd like, as long as you're reasonable about your tolerances and pass depth. You're not going to be milling aerospace stuff. If you need a .001 tolerance, an extrusion built CNC router isn't the right machine, but it's possible to keep it within 5 to 10 thou on a good day.. which is plenty fine for cosmetic cutting and often good enough for parts as well.
Re: CNCRP 48x48 Pro for machining aluminum?
Saw your video, congrats on your new machine!
You should get or build a fogbuster type coolant system for cutting metal on your machine.
Re: CNCRP 48x48 Pro for machining aluminum?
Quote:
Originally Posted by
nlancaster
Saw your video, congrats on your new machine!
You should get or build a fogbuster type coolant system for cutting metal on your machine.
Yep, that's on the to-do list. I actually have a second head for the fogbuster on my Tormach, so I might just use that and make my own tank for it. I'm not sure how to deal with the MDF, I don't want it getting damp of course.
Re: CNCRP 48x48 Pro for machining aluminum?
Just saw your video can you give more info on the current proximity sensor setup. This looks different than what is shown in other images I have seen. Specifically the Y axis sensors.
Re: CNCRP 48x48 Pro for machining aluminum?
Quote:
Originally Posted by
cowanrg
I was originally going to get a larger CNC vertical mill, so this is actually quite a bit cheaper, so I can throw a bit more money at it to get the most out of it.
Robert,
Do you have any impression on your new machines on cutting aluminum in comparison to your tormach as a reference. I am curious on the speeds / depth of cut / surface finish capability.