I need a good way to hold this

[Leon82]

i may be able to hold it upright with a huge 3 jaw chuck contraption but it wont fit thru the plallet changer.

any suggestions?

 

it is 13" round 16 long titanium

[jstell]

V-block cradle?  Or a wide slot with 'fence' walls to locate and keep it from rolling?

Strap clamps over the top with long bolts or studs to the pallet?

[Leon82]

45 minutes ago, jstell said:

V-block cradle?  Or a wide slot with 'fence' walls to locate and keep it from rolling?

Strap clamps over the top with long bolts or studs to the pallet?

when i did it in the 3 axis machine i made a cradle with the radius and used a 2 piece bolt down vise. but i wont have much clearance in this machine for that. we were hoping to increase the cutting aggressiveness.

 i can use some long studs and straps to reach the side. I'm putting a dovetail on it

that Titians guy had a big chuck in a makino video he dis. i think it was 3 individual jaws

[Kyle F]

Jeez, that's quite the chunk!

I could see dovetails on each end, held with maybe a vise like this one:

https://schunk.com/us/en/workpiece-clamping-technology/manual-clamping-systems/single-acting-clamping-vises/ksc-f/ksc-f-160-480/p/000000000000432620

480mm long Schunk Kontec w/ dovetail jaws.

But honestly most of my parts are much smaller so I am definitely no expert.

[jstell]

I am guessing the chain in the photo is how you loaded it into the machine?

You could try something like the pitbull from mitee-bite.  https://www.miteebite.com/products/pitbull-clamps/

Or make something similar to wedge in your dovetail cuts.

[Aaron Eberhard]

Pitbulls were going to be my suggestion.  This is just for the dovetail op?   

Any idea what kind of cutting force you're going to be putting against? i.e., how much clamping force you need to hold?

[Leon82]

1 hour ago, Aaron Eberhard said:

Pitbulls were going to be my suggestion.  This is just for the dovetail op?   

Any idea what kind of cutting force you're going to be putting against? i.e., how much clamping force you need to hold?

Yeah it's just to put the dovetail on. I have to probably rough two inches off. In the feeler I use the iscar  h400. But I also had that chain turn on the bottom and bolted the table so it couldn't fall out of that saddle..

 let it run overnight so I wasn't pushing it.

[Aaron Eberhard]

1 hour ago, Leon82 said:

Yeah it's just to put the dovetail on. I have to probably rough two inches off. In the feeler I use the iscar  h400. But I also had that chain turn on the bottom and bolted the table so it couldn't fall out of that saddle..

 let it run overnight so I wasn't pushing it.

According to HSMAdvisor, if you use a 5FL .75" and keep the DOC to 1" 12.3% (.0921") WOC, it'll generate ~735lb of cutting force. 

The two bigger sized pit bulls claim to have 6 or 12000lb of holding force.   I'd make some stand-offs to mount those at the end and dig into the middle of the ends.

Make a fixed side wedge and a clamp-driven wedge to lock the bottom in place after clamping with the miteebites, just to ensure it can't rock or get pushed since you're not holding it on the front/back?

[Leon82]

33 minutes ago, Aaron Eberhard said:

According to HSMAdvisor, if you use a 5FL .75" and keep the DOC to 1" 12.3% (.0921") WOC, it'll generate ~735lb of cutting force. 

The two bigger sized pit bulls claim to have 6 or 12000lb of holding force.   I'd make some stand-offs to mount those at the end and dig into the middle of the ends.

Make a fixed side wedge and a clamp-driven wedge to lock the bottom in place after clamping with the miteebites, just to ensure it can't rock or get pushed left or right (since you're not holding it on the front/back)?

Thanks, I'll check it out tomorrow 

[Aaron Eberhard]

@Leon82 - Someone just replied to my post, so I'm wondering how you ever made out here?

 

[Leon82]

7 hours ago, Aaron Eberhard said:

@Leon82 - Someone just replied to my post, so I'm wondering how you ever made out here?

 

I haven't done much yet. I modeled a fixture with some of the big pit bulls. Probably going to get on it more next month

[Leon82]

I'm thinking something like this might work. 

[Kyle F]

big chunk going on the mx850?

[Leon82]

1 hour ago, Kyle F said:

big chunk going on the mx850?

Yea grade 2 titanium 

[crazy^millman]

4 hours ago, Leon82 said:

I'm thinking something like this might work. 

I would put 3 on each side not 2, built I like building massive overkill fixtures. Funny some of the fixtures from 30 years ago are still be used at the company I worked for back in Florida. Seen fixtures from 20 years ago still be used at another company last year. I would also radius or chamfer the corners to keep any extra material inside the swing and not have sharp concerns create pinch points for loading and unloading the material.

[#Rekd™]

1 hour ago, crazy^millman said:

I like building massive overkill fixtures.

Better to be over built then under built!!!! I do the same no matter if it is at my house or in the shop.

[Leon82]

2 hours ago, crazy^millman said:

I would put 3 on each side not 2, built I like building massive overkill fixtures. Funny some of the fixtures from 30 years ago are still be used at the company I worked for back in Florida. Seen fixtures from 20 years ago still be used at another company last year. I would also radius or chamfer the corners to keep any extra material inside the swing and not have sharp concerns create pinch points for loading and unloading the material.

ok ill add them, they arent very expensive so its worth it. i will be cutting the corner off this is just a starting sketch

[Colin Gilchrist]

1 hour ago, crazy^millman said:

I would put 3 on each side not 2, built I like building massive overkill fixtures. Funny some of the fixtures from 30 years ago are still be used at the company I worked for back in Florida. Seen fixtures from 20 years ago still be used at another company last year. I would also radius or chamfer the corners to keep any extra material inside the swing and not have sharp concerns create pinch points for loading and unloading the material.

I was going to say 4 per side! Mitee-bites are nice, but not sure they provide the clamping forces to resist aggressive machining on such a large chunk of Ti.

My 2 Cents:

https://www.fixtureworks.com/store/pc/side-clamps-wide-jaw-cp102-s37.htm

https://www.fixtureworks.com/store/pc/side-clamps-pivoting-serrated-jaw-heavy-cast-iron-bj100-s2862.htm

[#Rekd™]

16 minutes ago, Colin Gilchrist said:

My 2 Cents:

https://www.fixtureworks.com/store/pc/side-clamps-wide-jaw-cp102-s37.htm

https://www.fixtureworks.com/store/pc/side-clamps-pivoting-serrated-jaw-heavy-cast-iron-bj100-s2862.htm

Awesome!!!!!!! Thank you for sharing!

[Aaron Eberhard]

18 minutes ago, Colin Gilchrist said:

I was going to say 4 per side! Mitee-bites are nice, but not sure they provide the clamping forces to resist aggressive machining on such a large chunk of Ti.

My 2 Cents:

https://www.fixtureworks.com/store/pc/side-clamps-wide-jaw-cp102-s37.htm

https://www.fixtureworks.com/store/pc/side-clamps-pivoting-serrated-jaw-heavy-cast-iron-bj100-s2862.htm

Those are snazzy, multi-mitee-bites