Thanks to Paul! It's nice to see you have some older grumpy friends in your network. Those guys are happy to share (if you show respect). I have a group of guys in my network that give me great tips I don't have as a one-man shop. Thanks for your work. Cheers.
Thank you! In my experience vacuum only works if you have enough surface area. For this part I would program a large array of parts fitting in the machine's envelope or, when smaller, the order made. I mounted my vacuum table with a large block on the bottom which can be held in the regular CNC vice that's there 95% of the time. I then tram the height of the table using a dial indicator to get it absolutely level with the x-y plane of the machine. Mount the rubber seal to the maximum size of the stock used and start milling. Holes are milled instead of drilled because I have to maintain vacuum during all operation. I leave 0,1 mm of material at the bottom. Last operation is cutting the parts loose at also 0,1 mm above the vacuum table. When the job is done I can simply fold the parts out of the left stock and use a dedicated small router (Makra 250) with a small carbide chamfering tool to get rid of the burs on the bottom. Holes are punched out first with a fitting pin. Works like a charm. Maybe a tip. All the best, Job
As a one man job I had to discover a lot of this by experimenting, measuring, failing and finally finding the right work-holding for my thin parts. Clamping an re-clamping very large thin parts is something I regularly do. Works great as long as you remember to make sure your tools don't hit the clamps that are above the material. If your tools move up something like 1/4" above the part and then performs a G0 move to the next starting position, you might be surprised to hit that "mountain" you used for clamping...
Machining thin material I default to double side tape or vacuum chuck. DS tape mainly for plastics because I prefer to use air blast for plastics. If a part has mounting holes, I take advantage of those for clamping, using plastic washers to protect the part. When using those generic strap clamps, I use some plastic shim stock (~.010") to keep the clamp tip from marring the part/material.
Amazing!, I usually machine small parts for firearms and its a challenge. Luckily my products do have holes to fix them to a plate. Casually, the other day I machined a big alluminum plate to hold up to 60 pieces (I need to improve night time) and I was puzzled to check how wavy the stock was. It is a 7075 T6 plate of 600x400x30 mm and it had about 0,3 mm of random warping. And intuitively I did the same that was recommended in this video of loose a bit of pressure for the last surface finishing. Thanks for the tips, I see all the videos! Greetings from Argentina
Awesome video! I was really excited to see him running that Bridgeport also. I have an older version of that machine (1998 VMC 1000/22) and I love it 😁😁 I always interesting to see what others cook up for work holding. You can really build off of fresh ideas.
Good video. But I feel like he missed an opportunity to talk about residual stress in the material and how this stress is relieved when machining, which will cause flatness issues especially for thin parts.
Very cool notes, had to learn a few of these through trial and error and some of these I'm gonna take going forward. One thing I've found for certain thin parts with a lot of holes that need to be extremely consistent is that spring-loaded deburring tools (Cogsdill) can be worthwhile. But 90% of the time I find a quick hit with an aircraft sheet metal rivet deburring tool is fast and consistent enough for typical holes. If I have thin parts with large windows, I've never thought to just pocket or adaptive out the big empty. I always tend to pop holes in them for hold-down screws, and then machine out those windows last, often slotting with a few tabs first and then going in at the very end to skim cut the tabs away. Alternatively those big windows go first, and then have a custom fixture that drops into the window and clamps the part there all along that perimeter
@@ernestomayer6485 It's a good option when doing a bunch of them and its worth the time for the fixturing. Also handy if you are taking a waterjet blanks that already have big gaps.
Mitee Bite had a new holding wax at IMTS. Heat gun to melt it, hold your part, and heat gun to release, clean it with acetone. Way nicer than any of the super glue crap I've tried!
Hot glue works the same way. There are different kinds, common clear is the weakest, yellow-ish is nice and strong, black is more rubber-y. Cleans off with IPA. Great for odd-shaped parts, but can take a while to heat up if the fixture/part is fairly large since you have to heat the whole thing. After looking up the product, i do see the advantage of it being in a sheet though, great for thin flat parts.
Double sided tape and hot melt works well too when not using coolant. Fixture plate must be flat and workpiece must be clean and free of any oils/debris
Taugetec make a negative holder with positive geometry insert. Basically the insert has huge ramps on it. They work great at chipping aluminium and the holders don’t Waller out like DCMT type as the walls are vertical with a pin clamp not a tiny screw. 4 edges on a D style too as it’s negative
Carbonite coated jaws are a life saver when wanting to hold on with little force and when dealing with parts that have terrible burn profiles. We would be throwing parts often had we not coated our jaws.
Haha I tell people to point those step clamps down toward the part only because I used to tell them level but they would end up angled wrong and lifting the part
People that need to lift their leg up and put it on a machine, are not the ones you need to learn from. They are set in their ways, nobody can say otherwise.
Really like how Paul explains things
I always enjoy hearing from Paul. He reminds me of some people I have worked with who taught me a lot.
Holding new parts with extra stock makes life so much more flexible. Rewoking finished components is where things can really get challenging. 🙂
Awesome video, love those little tips you can't find in any text book and only hear from experienced workers.
Thanks to Paul!
It's nice to see you have some older grumpy friends in your network. Those guys are happy to share (if you show respect). I have a group of guys in my network that give me great tips I don't have as a one-man shop. Thanks for your work. Cheers.
Paul knows his stuff! Everything he talks about has something to put in your bag of tricks.
Thank you! In my experience vacuum only works if you have enough surface area. For this part I would program a large array of parts fitting in the machine's envelope or, when smaller, the order made. I mounted my vacuum table with a large block on the bottom which can be held in the regular CNC vice that's there 95% of the time. I then tram the height of the table using a dial indicator to get it absolutely level with the x-y plane of the machine. Mount the rubber seal to the maximum size of the stock used and start milling. Holes are milled instead of drilled because I have to maintain vacuum during all operation. I leave 0,1 mm of material at the bottom. Last operation is cutting the parts loose at also 0,1 mm above the vacuum table. When the job is done I can simply fold the parts out of the left stock and use a dedicated small router (Makra 250) with a small carbide chamfering tool to get rid of the burs on the bottom. Holes are punched out first with a fitting pin. Works like a charm. Maybe a tip. All the best, Job
You need to get Paul DeBolt and Robin Renzetti in the same room. Turn on the cameras and make some magic.
I second this, and raise you Tom Lipton
That's the one attribute of being a machinist.....you never stop learning.
As a one man job I had to discover a lot of this by experimenting, measuring, failing and finally finding the right work-holding for my thin parts.
Clamping an re-clamping very large thin parts is something I regularly do. Works great as long as you remember to make sure your tools don't hit the clamps that are above the material. If your tools move up something like 1/4" above the part and then performs a G0 move to the next starting position, you might be surprised to hit that "mountain" you used for clamping...
I’m getting a RobRenz vibe from him I really like the details in his explanation
Nah, this guy is a its my way or the highway person.
Machining thin material I default to double side tape or vacuum chuck. DS tape mainly for plastics because I prefer to use air blast for plastics. If a part has mounting holes, I take advantage of those for clamping, using plastic washers to protect the part.
When using those generic strap clamps, I use some plastic shim stock (~.010") to keep the clamp tip from marring the part/material.
Love the Hitachi Seiki in the background! Great machine...we' have had ours since 1994!!!
Amazing!, I usually machine small parts for firearms and its a challenge. Luckily my products do have holes to fix them to a plate.
Casually, the other day I machined a big alluminum plate to hold up to 60 pieces (I need to improve night time) and I was puzzled to check how wavy the stock was. It is a 7075 T6 plate of 600x400x30 mm and it had about 0,3 mm of random warping. And intuitively I did the same that was recommended in this video of loose a bit of pressure for the last surface finishing.
Thanks for the tips, I see all the videos! Greetings from Argentina
De bolt, de clamp and de screw are de best ways to secure de part. 😁
You know that de feet of de duck went over de fence before de tail?
Some info on the beveled nuts and washers would be awseome!
Very informative!
Awesome video! I was really excited to see him running that Bridgeport also. I have an older version of that machine (1998 VMC 1000/22) and I love it 😁😁
I always interesting to see what others cook up for work holding. You can really build off of fresh ideas.
Good video. But I feel like he missed an opportunity to talk about residual stress in the material and how this stress is relieved when machining, which will cause flatness issues especially for thin parts.
Paul is awesome.
Paul is the man. Got star potential
We have 5 Bridgeport CNC machines, almost the same es Paul's and I also learned it from books a few years ago xD Heidenhain has amazing documentation.
Got a guy at work, read a book to run a cnc or nc machine. He's really good at it
Very cool notes, had to learn a few of these through trial and error and some of these I'm gonna take going forward.
One thing I've found for certain thin parts with a lot of holes that need to be extremely consistent is that spring-loaded deburring tools (Cogsdill) can be worthwhile. But 90% of the time I find a quick hit with an aircraft sheet metal rivet deburring tool is fast and consistent enough for typical holes.
If I have thin parts with large windows, I've never thought to just pocket or adaptive out the big empty. I always tend to pop holes in them for hold-down screws, and then machine out those windows last, often slotting with a few tabs first and then going in at the very end to skim cut the tabs away.
Alternatively those big windows go first, and then have a custom fixture that drops into the window and clamps the part there all along that perimeter
I like that last option. Is it better to avoid distortion? I think of it like an inverted vice that clamps by expansion.
@@ernestomayer6485 It's a good option when doing a bunch of them and its worth the time for the fixturing. Also handy if you are taking a waterjet blanks that already have big gaps.
Great Video! Thank you!
Mitee Bite had a new holding wax at IMTS. Heat gun to melt it, hold your part, and heat gun to release, clean it with acetone. Way nicer than any of the super glue crap I've tried!
Hot glue works the same way. There are different kinds, common clear is the weakest, yellow-ish is nice and strong, black is more rubber-y. Cleans off with IPA.
Great for odd-shaped parts, but can take a while to heat up if the fixture/part is fairly large since you have to heat the whole thing.
After looking up the product, i do see the advantage of it being in a sheet though, great for thin flat parts.
Double sided tape and hot melt works well too when not using coolant. Fixture plate must be flat and workpiece must be clean and free of any oils/debris
Taugetec make a negative holder with positive geometry insert. Basically the insert has huge ramps on it.
They work great at chipping aluminium and the holders don’t Waller out like DCMT type as the walls are vertical with a pin clamp not a tiny screw. 4 edges on a D style too as it’s negative
Fixture play also important role
Carbonite coated jaws are a life saver when wanting to hold on with little force and when dealing with parts that have terrible burn profiles. We would be throwing parts often had we not coated our jaws.
Can you expand on this a little please?
Very interesting
Haha I tell people to point those step clamps down toward the part only because I used to tell them level but they would end up angled wrong and lifting the part
🤩🤩 🤩 🤩 🤩💯 💯 👍 👍👍👍👍👍
❤️❤️✌️
People that need to lift their leg up and put it on a machine, are not the ones you need to learn from. They are set in their ways, nobody can say otherwise.
First