Progressing From The Dark Ages.

Discussion on all milling machines vertical & horizontal, including but not limited to Bridgeports, Hardinge, South Bend, Clausing, Van Norman, including imports.

Moderators: Harold_V, GlennW

armscor 1
Posts: 167
Joined: Sun Jun 12, 2016 3:12 am
Location: Philippines

Re: Progressing From The Dark Ages.

Post by armscor 1 » Wed Jul 29, 2020 4:09 pm

Hi Guys, cut my DRO scale with some trepidation, trusty Dremel to the rescue with a small diamond coated burr, the hardest part was cutting the aluminium, tough stuff, no idea what type.
The "X" scale now fitted and working fine.
Now to fit the "Y" scale.
Heaps of features on the DRO, some I don't understand, do some more research.
Attachments
20200729_050811.jpg
20200729_181522.jpg

Harold_V
Posts: 18222
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Progressing From The Dark Ages.

Post by Harold_V » Thu Jul 30, 2020 1:54 am

armscor 1 wrote:
Wed Jul 29, 2020 4:09 pm
the hardest part was cutting the aluminium, tough stuff, no idea what type.
If you used the diamond tool to make the cuts, I think you'll discover that it's not tough, it just loads the tool so it won't cut. Performance might be enhanced by applying kerosene, but you'd be far better served not using that type of device for cutting aluminum.

H
Wise people talk because they have something to say. Fools talk because they have to say something.

armscor 1
Posts: 167
Joined: Sun Jun 12, 2016 3:12 am
Location: Philippines

Re: Progressing From The Dark Ages.

Post by armscor 1 » Thu Jul 30, 2020 2:45 am

Hi Harold,
I used the 1/8" tapered diamond burr to cut the fragile glass scale, cut like butter.
Used a 8mm carbide slot drill to cut the scale frame to give access to the glass scale and the aluminium was tough to cut.
Must be extremely rigid as the glass scale is only 3/32" thick and 1/2' wide. It has to soak up vibration and resist any bending moments.
The magnetic scales are immune from that but of course more expensive.

Harold_V
Posts: 18222
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Progressing From The Dark Ages.

Post by Harold_V » Thu Jul 30, 2020 3:00 am

Hmmm. That's interesting. I've machined pretty much every alloy of aluminum and have never experienced one that wouldn't cut reasonably freely, although some are rather "sticky". I can't help but wonder if, maybe, you had some chip welding in the flutes. If they get packed, cutting becomes a miserable process and often results in a broken end mill, assuming one is using power feeds or doesn't let up on feed at the appropriate time.

Did you use any lubricant while cutting the aluminum? If not, that may be why you struggled. If chip welding was an issue, you should find signs of that on the cutter, where aluminum streaked off and built up.

Congrats on your success!

H
Wise people talk because they have something to say. Fools talk because they have to say something.

armscor 1
Posts: 167
Joined: Sun Jun 12, 2016 3:12 am
Location: Philippines

Re: Progressing From The Dark Ages.

Post by armscor 1 » Thu Jul 30, 2020 4:28 am

Hi Harold, avoided lubricant like the plague, difficult to access the glass scale to clean, taped the slot and blocked the end with tissue paper.
After cutting the glass I completed the surgery cutting the aluminium with a hacksaw and you could feel it was tough.
Faced of the end with a slot drill.
Showed the Missus with the DRO reading out with power feed, more interested in watching the power feed spinning over!

pete
Posts: 1877
Joined: Tue Feb 10, 2009 6:04 am

Re: Progressing From The Dark Ages.

Post by pete » Fri Jul 31, 2020 6:11 am

I've found some extruded aluminum alloys aren't really designed to be machinable at all. They tear more than cut. I thought I'd scored a bunch of old but free 1/2" aluminum shafts one time until I chucked one up in the lathe. Nothing I tried for speeds, feeds, cutting tools or cutting lube would get even a passable surface finish on it. I've not had any that was very tough though. Even HSS will drill or machine titanium and it's a whole lot tougher than any aluminum alloy I know of.

armscor 1
Posts: 167
Joined: Sun Jun 12, 2016 3:12 am
Location: Philippines

Re: Progressing From The Dark Ages.

Post by armscor 1 » Fri Jul 31, 2020 3:34 pm

I suspect the Aluminium alloy is Duralumin.
Remember my Mentor telling me they had found a fuel tank dropped from an aircraft during WW2 in Holland, he said it was almost impossible to cut.

armscor 1
Posts: 167
Joined: Sun Jun 12, 2016 3:12 am
Location: Philippines

Re: Progressing From The Dark Ages.

Post by armscor 1 » Fri Jul 31, 2020 7:39 pm

Job finished, sore arm cranking the hand wheels to tram the scales!

Post Reply