[AiR_GuNNeR]

They look great Ray. Can you give us an idea what each piece is for?

[SCzEngrgGroup]

Those look great. What brand/type of end mill are you using for your aluminum? I know you're a 2 flute fan. I've been getting great results with both Niagara and YG 3 flute TiAlN coated but haven't had a chance to compare side by side with 2 flutes. I did come across an article (Aluminum Machining, Machining Aluminum, High Speed Machining | Radical Departures) that claims that uncoated cardbide (for coarse carbide at least) is better for aluminum than all coatings other than DLC. They also prefer 2 flute for the extra rigidity as well of course for chip clearance. I'll be giving some uncoated end mills a shot next.

At the moment, I'm using mostly Hertel HSS 2-flutes - about $12 each from Enco. I used to use Putnam/Greefield, but they seem to no longer be available. I've used 3-flute carbides, but the MRR is no higher, and the finish no better, despite being 3X the cost. So, why spend the money?

Regards,
Ray L.

[SCzEngrgGroup]

Ray;
Are you planning a tool changer for this machine? That would be neat!
Bill

Bill,

Actually a 12-tool ATC has been fully designed since long before the machine showed up,but it will likely be a couple of months before I have time to build the first one - I'm way behind on other work.

Regards,
Ray L.

[SCzEngrgGroup]

They look great Ray. Can you give us an idea what each piece is for?

The three large parts on the left are one of the many parts for a distributor-less ignition kit I sell for classic Jaguar cars (mostly E-types). The rest are for a rather unique power drawbar you'll be seeing soon.

Regards,
Ray L.

[SCzEngrgGroup]

After suffering several more bogus limit trips, due to aluminum chips piling up on the exposed prox sensors, I took about an hour and a half and did something about it. The range of a prox sensor is about 40% less for aluminum than it is for steel or iron, so it seemed reasonable to me that if I could prevent the chips from getting too close to the sensor, it would prevent false trips, but still work properly with the steel limit "flags". A little testing determined that about 0.100" space worked well. So, I machined a couple of covers out of some scrap UHMW, and screwed them over the sensors. Works perfectly! I can pile 6061 chips 1" deep on top of the cover, with no false trips, but when the limit flag approaches, it triggers perfectly.

These are only needed on the Y axis, as the X axis sensor is always covered, and the Z axis sensor is out of range of any chips.

The bottom side:
Attachment 181519

The top side:
Attachment 181520

And installed:
Attachment 181521

Regards,
Ray L.

[Eric603]

The correct resistors are not expensive - last one I bought was under $20.

[skray775]

Great minds think alike! LOL

I was convinced after reading many threads that I had to have 3 flute, high helix, carbide end mills to do
some real machining.

Pushing a 3/8" three flutes at the proper speeds would lead to a situation were the machine would
bog down if the radial engagement suddenly changed like milling a odd shaped pocket. That would lead to
clogged flutes and a broken bit or destroyed part.

I went back to two flute Atrax (carbide) or Hertel (hss) and run them at a proper speed without the worry of a clogged
flute the second I turn my back.

At the moment, I'm using mostly Hertel HSS 2-flutes - about $12 each from Enco. I used to use Putnam/Greefield, but they seem to no longer be available. I've used 3-flute carbides, but the MRR is no higher, and the finish no better, despite being 3X the cost. So, why spend the money?

Regards,
Ray L.

[SCzEngrgGroup]

Great minds think alike! LOL

I was convinced after reading many threads that I had to have 3 flute, high helix, carbide end mills to do
some real machining.

Pushing a 3/8" three flutes at the proper speeds would lead to a situation were the machine would
bog down if the radial engagement suddenly changed like milling a odd shaped pocket. That would lead to
clogged flutes and a broken bit or destroyed part.

I went back to two flute Atrax (carbide) or Hertel (hss) and run them at a proper speed without the worry of a clogged
flute the second I turn my back.

Getting your money's worth out of carbide requires a high-speed, high-power spindle - beyond what most small machines have - and, most of all, they require a very rigid machine to reach anything close to their full potential. Carbide is also good for small tools - 1/4" and under - for the sake of increased stiffness. But, while they'll give you better surface finish on roughing cuts, they won't cut any faster than a comparable HSS tool, as you won't be able to spin them fast enough.

Regards,
Ray L.

[SCzEngrgGroup]

Great minds think alike! LOL

I was convinced after reading many threads that I had to have 3 flute, high helix, carbide end mills to do
some real machining.

Pushing a 3/8" three flutes at the proper speeds would lead to a situation were the machine would
bog down if the radial engagement suddenly changed like milling a odd shaped pocket. That would lead to
clogged flutes and a broken bit or destroyed part.

I went back to two flute Atrax (carbide) or Hertel (hss) and run them at a proper speed without the worry of a clogged
flute the second I turn my back.

Getting your money's worth out of carbide requires a high-speed, high-power spindle - beyond what most small machines have - and, most of all, they require a very rigid machine to reach anything close to their full potential. Carbide is also good for small tools - 1/4" and under - for the sake of increased stiffness. But, while they'll give you better surface finish on roughing cuts, they won't cut any faster than a comparable HSS tool, as you won't be able to spin them fast enough.

Regards,
Ray L.

[MRM RCModels]

After suffering several more bogus limit trips, due to aluminum chips piling up on the exposed prox sensors, I took about an hour and a half and did something about it. The range of a prox sensor is about 40% less for aluminum than it is for steel or iron, so it seemed reasonable to me that if I could prevent the chips from getting too close to the sensor, it would prevent false trips, but still work properly with the steel limit "flags". A little testing determined that about 0.100" space worked well. So, I machined a coupld of covers out of some scrap UHMW, and screwed them over the sensors. Works perfectly! I can pile chips 1" deep on top of the cover, with no false trip, but when the limit flag approaches, it triggers perfectly.

These are only needed on the Y axis, as the X axis sensor is always covered, and the Z axis sensor is out of range of any chips.

The bottom side:
Attachment 181519

The top side:
Attachment 181520

And installed:
Attachment 181521

Regards,
Ray L.

Ray,

What feeds/speeds are you seeing with hss?

[SCzEngrgGroup]

Ray,

What feeds/speeds are you seeing with hss?

Right now, I'm being pretty conservative, so not pushing the limit at all. For my "workhorse" 1/2" 2-flutes in 6061, I'm currently running 3400 RPM, 24 IPM, 0.5" WOC, 0.25" DOC, with flood coolant. This is a 3.0 cu. in./min MRR. The machine is very happy with this, and the tools last a looooong time (unless I do something stupid). It will do more, probably topping out somewhere between 3.5 and 4.0 MRR, but for now I'm more interested in just getting work out reliably, and will optimize later when I have more time. There are too many "new" things going on right now (new machine, KFlop conversion with new BOB, many software/firmware changes, VFD changes, new coolant, new PDB, etc.). For finishing, I usually run about 3900 RPM, 35 IPM, up to 1.25" DOC.

Regards,
Ray L.

[SCzEngrgGroup]

Almost forgot - I also made a couple of covers for the table, to keep the T-slots from filling with chips. I got a few feet of ribbed carpet running from Home Depot, and cut these to fit around my vise. I bought enough extra to make several sets for different setups.



Regards,
Ray L.

[neilw20]

Neat adjustable end stop on the vice.

[SCzEngrgGroup]

Neat adjustable end stop on the vice.

Can't take credit for that - I copied it: Pro Vise Stop Single Side

It's one of the most useful things I've ever made, and easy to make. Here's a better picture:

Attachment 181540

I did my own knock-off of the ProTram as well, but can't find a picture of it right now...

Regards,
Ray L.

[neilw20]

Ray,

A short question about your spindle index plate.
Did you attach it the stock left hand LH M22 nut/collar that comes with machine or make a new one, M22 LH thread included?

Cool idea for the proximity detectors.!!

regards
Neil

[SCzEngrgGroup]

Ray,

A short question about your spindle index plate.
Did you attach it the stock left hand LH M22 nut/collar that comes with machine or make a new one, M22 LH thread included?

Cool idea for the proximity detectors.!!

regards
Neil

Neil,

Made a new one.

Regards,
Ray L.

[neilw20]

LH thread milling, I suspect.
That was my cut on things
Thread Milling Photos by neilw20_2008 | Photobucket

[SCzEngrgGroup]

Neil,

No, I did it on a lathe - haven't gotten into thread-milling.... yet!

Regards,
Ray L.

[neilw20]

My lathe is imperial, and just can't get the correct pitch without a lot of compound slide fudge.
It was worth making the cutter, as an exercise, and it will surely find more jobs.
20 tpi = 1.27
20 tpi = 1.21
17 tpi = 1.49
Just plain not close enough.
I suppose I could leave the thread length quite short and ignore the error.
One day I will make a 100 to 127 gear for the lathe, or CNCing it is really easier.

[SCzEngrgGroup]

Neil,

I would think 17 TPI would be close enough. I have no idea what the precise lead on mine is, but I've made several of those parts, and all fit perfectly. In fact, they fit better than the "factory" piece.

Regards,
Ray L.