I bought a Makino today...

[Garwood]

I suppose most folks don’t put much effort into cutting the base nice since they plan on finishing the sides in the machine it will be used in.

I get that, but it's BAD. It's a bad finish and doesn't seem flat enough to make a good connection.

I just want to be sure I'm putting it together right.

Seems like if the bottom is not flat and I cinch it down to the pallet it would distort the pallet and the pallet won't seat accurately- it could rock.

These tombstones are a lot meatier than the pallets.

 

[Vancbiker]

Yeah, wasn’t saying it’s OK to do a poor job on the base, just that I’ve seen it done.

 

[alphonso]

Blanchard!!!!

 

[Barbter]

Blanchard!!!!

Ha! 10bucks says he's already done it!

 

[Garwood]

My Blanchard will only do about 12" tall parts. The University I bought it from made the segment chuck for it and they made it super tall, so not much headroom under the wheel. These stones are 21" tall.

I could fit them in my kitamura 5X VMC, but I think the smartest way to do anything to them would be to lay the stones on their sides on the Makino then I could indicate the sides of the tombstones, line them up nice and skim off the bottoms.

I have a text into a friend that scrapes machines to see what it'd take for him to bulldoze off a couple thou with his power scrapers for good contact. That's not going to correct for any misalignment though.

 

[Garwood]

The pallets in this Makino have five 9/16" t-slots on 3" centers.

Is there a reason not to use a 1/2" bolt in each t-slot for 10 total? There would be 5 bolts on 2 opposite sides, 2 sides with no bolts.

 

[Vancbiker]

No reason I can think of. Personal preference, I'd do 8 bolts total so each face had 3 bolts along it.

 

[Spruewell]

Ready for another bad idea? Build up the bottom with braze (or weld), then re-machine it so the Y on all your tombstones are identical.

Or you could go through and machine all your bases to match the shortest one

 

[Barbter]

My Blanchard will only do about 12" tall parts.

You're gunna need a bigger Blanchard!

I'm with Sprue - spend a day measuring them all and match the smallest one. I'd also run a clock up the Y and across the X to see how square they all are.
Although you'll never get them "exact" and will always need a tweak of your datums for spot-on work....

 

[lobust]

I'd spend some time checking that any of this is necessary. Reference flat and blue.

It's perfectly possible for a facemill to leave a bad finish that is also quite flat. The steps you are feeling are quite possibly not tram error, just shallow spots at the edge of the facing pass where the fpt is effectively zero. That is an unavoidable side effect of facing in multiple passes, but becomes more apparent as you increase the feedrate and depending on the wiper land size on the inserts.

If it actually is too rough to use, then I'd be measuring the hole locations and parallelism of the working sides of the tombstone to determine if they are all reasonably the same, at which point it should be possible to fix some locating pins to your pallet so that you can easily make all of them the same.

Even after you do all that, you'll probably want to recut the working faces again after you mount the tombstone proper.

But again, before I did any of this, I'd be making damn sure it was absolutely necessary...

 

[Doug]

Yup ^^^ Surface finish does not equal accuracy always.

 

[Garwood]

My old spotting compound has dried up, so I can't spot it with my little granite plate.

It's not that I'm worried about an imperfect finish. It's more that there's like 2% contact on half the tombstone base.

Flat or not, I'm not real keen on using it as is. I have a lot riding on this machine performing OK.

I'm filling up the Makino's coolant tank and loading tools now.

 

[Garwood]

This pictures for Mud showing the bomb hoist doing its thing.

 

[Mud]

Thanks Garwood. I have a cart like that presently supporting a Skyhook. The vertical post is 2" x 16ga which works fine for the 200 lb cap. skyhook but I want to lift 600+. What dia and wall thickness are you using there for the bomb hoist?

 

[Garwood]

2" galvanized pipe lol

These tombstones are about that. I'll weigh one eventually. They're atleast 500.

 

[Garwood]

Just finished the 1st stone and bolted it on loosely. I'm going to indicate it all over, torque the bolts then laser cut and grind some alignment plates for the sides.

This has been a lot of learning! I'm not used to such a small work envelope or loading through the pallet changer. Nothing that complex, just a need to think ahead more. Like I set up the first tombstone to remachine the bottom and I mostly thought about where to place it so I could indicate it and fit it through the pallet changer. Then I find out I need to raise it 2.75" because, well, it's 400mm and I have exactly 400mm of travel. But I had a bunch of work into fixturing and all that would be undone to do a pallet change so I could use my bomb hoist cart to raise it. So I tried lifting the tombstone with Jack's, but it's way too unbalanced and hard steel on cast iron is slick! I didn't want to die in this Makino or wreck the way covers so instead I moved 47 things so I could get the forklift to the Makino, then I pulled the plexi off the top and used the forklift the raise the stone the 2.75".

Programming and setup was easy. HMC is way easier than a 3+1 VMC.

 

[Garwood]

I spose that extra few hours I spent indicating the fuck out of everything paid off.



The stones taper .0009" fat at the bottoms so I split the difference. Looks about .0004" fat at the bottom indicating down each face.

 

[Vancbiker]

I spose that extra few hours I spent indicating the fuck out of everything paid off……

I usually find that it does. Those extra couple tenths are usually worth chasing when doing that kind of work.

 

[Garwood]

I usually find that it does. Those extra couple tenths are usually worth chasing when doing that kind of work.

It gives me a pretty good idea what the machine's capabilities are too. After cutting this tombstone I believe X, Y and Z are square within a couple tenths and so is the top of the pallet.

Still blows my mind that nobody else saw this old Makino as a good deal.

 

[Mud]

'Cause it's not a HAAS...