SEPA Milling Party?

[t1066]

Ok, here is a picture of the issue:

[mrat]

We always used kero for aluminum in the machine shop. Or a cool mist set-up.

[Walleye Hunter]

This is an end mill that normally has no issue cutting aluminum. Coolant line got blocked by chips, and this was the result.



Also, got my router in from the garage. Looks to be in good shape, and depth adjustments should take less than 15 seconds each.

I don't understand why your metal is coming out in particles rather than chips. Is it because you're drilling with it? I can understand how particles would stick together like they were glued if oil was added to the mix. Chips are too heavy for cutting oil to make them stick together.

[Walleye Hunter]

GRRGGGHHHH!!!!

I'm very unhappy with this jig at the moment. I was doing a test assembly and the forward take down pin wasn't fitting through.

Did some checking, and the hole in the jig for that position is 0.015" too close to the plate. You can't fit the lower in place without modifying the jig plate to give it room. I'll post a picture later today with arrows to show the problem. Fortunately, they sell replacement plates, so it shouldn't be a big deal for them to express out a replacement one.

I'm still happy with the design though, this is a quality control issue. Also, looking through the setup instructions again, the buffer location screw is hollow and designed to act as a shop vac hose mount.

The precision of these things impresses me. So far all of our blanks have fit into the jig with surgical precision. However, a friend left a plastic finished lower with me and it will not fit into the jig, the alignment holes don't match up.

[t1066]

I don't understand why your metal is coming out in particles rather than chips. Is it because you're drilling with it? I can understand how particles would stick together like they were glued if oil was added to the mix. Chips are too heavy for cutting oil to make them stick together.

It cuts chips when there is coolant. But when the coolant got blocked, the chips don't get blown out of the hole, and the tool heats up and basically welds the chips back into a mashed-potatoes consistency. When the tool comes out of the part, the metal cools down and you wind up with it looking like that.

One of the important functions of the type of coolant that was being used is chip removal from the cutting area.

[t1066]

Quick video of what the coolant I'm talking about looks like:



Sorry about the vertical video, but it was throwing enough hot chips out the door as it was. I didn't want it open any wider.

[Walleye Hunter]

Quick video of what the coolant I'm talking about looks like:



Sorry about the vertical video, but it was throwing enough hot chips out the door as it was. I didn't want it open any wider.

That's a genuine bath there and fast milling action, nothing like that going on here!

ETA: After milling a round in the block I stop, vacuum the chips and run the mill head down a couple of cranks. I had started making a video but I had the definition too high and used up the whole memory before I was done. I'll change that setting and hopefully be able to make and edit a short video on how it goes here.

[t1066]

Got in contact with 80% Arms. They are shipping out a replacement plate in 24 hours and sent me a free return label to send the bad one back. That is good customer service!

[Walleye Hunter]

Got in contact with 80% Arms. They are shipping out a replacement plate in 24 hours and sent me a free return label to send the bad one back. That is good customer service!

Yep, that is good, hope the new one works.

1st weapon completed. When it came time to install the trigger, the trigger hole in the lower was not long enough and I had to open it up a little more. Other than that all seems to function well, now I need to go try it out. And it looks like I need to get sights for it, I don't see any in the box.

[t1066]

Well, they shipped the large router baseplate yesterday. Assuming they ship out the replacement jig plate today like they said they would, I should have everything I need to use it by Friday.

Want me to bring it over this weekend and give it a try? If not, I'll give it a run at my place.