[louieatienza]

You could easily duplicate the brush carrier from a piece of Phenolic Sheet. It will not burn.

Well, it would need to be something like G10-FR4 for it not to burn. The paper and cloth based stuff will burn. Cutting fiberglass however kind of sucks if you don't have PCD endmills. Also don't know how smooth the brushes would move or if they'd catch or bind...

[gadgets]

Piece of cake. I've done it many times in my 52 years of being a machinist using the fiberglass based phenolics. He has a cnc mill and is learning g-code. Perfect learning project. Or he could use a rotary table as I have to machine around the stand-offs and cut the bore. use an end mill to cut the wire slots and a woodruff key cutter for the brush slots.

[RCaffin]

I'm late to the party on MQL. Oh well.

I use pulsed mist with a continuous air blast on Al alloy. Maybe 0.5 seconds of mist every 20-30 seconds. It's automated.
The liquid is 3 parts kero to 1 part cheap olive oil. 1/2 L of the mix lasts for many many months.
Parts come out dry - or very close, and the risk of fire is zero. There is negligeable smell. (Diesel - no thanks!)
Alcohol is also good for Al, but you end up drunk...

Cheers
Roger

[ihavenofish]

zero chance of fire, or just that you havent had one yet?

[handlewanker]

Hi....there you go, a simple mist coolant solution off the shelf.

One big question........how much air flow in litres per minute will I need to make it work and at what pressure.........mist cooling would probably be the only piece of gear that needs air.

On the topic of the electric PDB........you fix one thing and the next component in line fails etc.

I think it's going to be no non starter making a new brush carrier if the rest of the mechanicals being steel on plastic are only designed to work with the 12 volt motor power.

I'm working on a design that uses a cam and a motor geared down to approx. 15 rpm that runs on 24 volts so I can probably use the same transformer.

I already have a 2 stage double worm geared motor that runs at 3 rpm and 240 volts, but that's too slow......but before that happens some idea of the torque to turn the cam is needed.

The next trial device will be one with a couple of pillow block bearings to carry a cam and spindle actuated with a lever to test the torque loading........... a large truck type windscreen wiper motor might do the trick as they're geared down with a worm and worm wheel.
Ian.

[high-side]

It would seem for someone who refuses to add air to the machine for the PDB you should skip the complication of the future-failures-to-come electric version too. I think a well designed and made manual-lever type would serve you well.(Like on the Novakon machines) You don't seem like the type that's going to program for multiple tools, or implement a tool changer on your machine due to you have already "pawned the family jewels" to buy the SVM . Just use a program stop in your G-code, and swap out to the next tool if needed. Simple and easy.

[LeeWay]

He doesn't like simple or easy :-)


Sent from my iPhone using Tapatalk

[G59]

He doesn't like simple or easy :-)

I agree. The Novakon system lever/ would serve him well. Especially when most of his work is prototyping and one offs.

[handlewanker]

Well, it would need to be something like G10-FR4 for it not to burn. The paper and cloth based stuff will burn. Cutting fiberglass however kind of sucks if you don't have PCD endmills. Also don't know how smooth the brushes would move or if they'd catch or bind...

Well, I was going to make the brush carrier out of some 3mm thick red fibre sheet I have and a pair of brass brush carriers, but as the next component in line is the armature windings, if they fail then it's a major rebuild..........making a brush carrier is relatively simple, but making them too good and they'll still be there when the rest of the device fails.

Also, I don't think you can get enough wire on an armature of that size to rewind for 24 volts and the iron circuit is probably under sized too.
Ian.

[LeeWay]

He thinks in manual mode, but dreams of electric PDB's.
Gotta love automation at least to some extent.

[handlewanker]

Hi, the quest for the ideal solution is a twisted path of what is practical and can be made and what will work but is totally impractical even if it could be made.

I browsed EBAY for an actuator that would fit the bill but nothing hit the sweet spot, but while doing so I came across some electro magnets that fell in nicely with one of the designs I'd been working on.

Getting enough force in a small package at the voltage and amps available is a compromise you have to make.

But all is not lost.......an electro magnet, with the power ratings of 80Kg lifting force using a 24 volt supply and a consumption of .45 Amps all in a package of 65mm diam and 30mm long cost just A$35 post free from China.

The design I'm working on calls for 4 magnets around a central shaft with a steel plate on top......looks like an umbrella..........that will give 320 Kg of force to pull the spindle down using the same transformer of 24 volts and a total consumption of 1.8 amps, tot al cost of A$140 plus a capacitor and resistor etc.

To control the sudden pull from the magnets that would have a hammer blow effect, I'll use a resistor capacitor combination to let the amps in gradually.....about a 2 second time lag should do the trick.

I think this is about as simple as you could get....only one moving part and that is just a piece of steel rod with a steel plate on top, and a spring underneath to return the rod....not even sophisticated bearings to guide the rod, just a hole in the steel base plate.

It's possible that the existing steel enclosure will be too small for the four 65mm diam magnets to fit in......have to check......smaller magnets at 40Kg pull are 45mm diam but might not exert enough pull to depress the draw bar......suck it and see etc..

While the need for simplicity is opposed to the outcome, I think this solution is about as cost effective and practical as you can get.

I like the idea of the push button electro solution, even though the manual one is also effective and even though no ATC is in the picture.....the dwell time in the middle of a G code sequence is just a spindle up and M05 to stop the spindle and an M01 to pause the program........already done that exercise so I know it works.

The duty cycle for the magnets is approx. 10 minutes continuous on time.....so it'll be on for a few secs to release the tool and on again to reload a tool.......this will cut out any need for limit switches and it will be self docking once the tool is removed......click on to go down, release to go back up.
Ian.

[louieatienza]

Here you go...

Exlar GSM30 0601 MCM AB5 168 Linear Actuator | eBay

[handlewanker]

He doesn't like simple or easy :-)


Sent from my iPhone using Tapatalk

Hi, I think you confuse simplicity with practicality........on that basis a wrist watch is a desirable item but it's complicated.........you could adopt the idea of simplicity and have a small sun dial on your wrist bit that's not practical.

Just remembered a joke.......the first practical wrist watch for time estimation was invented over 3 thousand years ago by Alexander the Great.

In one battle it was vital to start the battle at the time when the sun was at it's highest or midday.......so Alex wrapped a piece of cloth around his wrist doused with a solution of a secret substance that turned black when exposed to strong sunlight.

In recorded history, this became know as "Alexander's Rag Time Band".......LOL.
Ian.

[G59]

STOP...You're not thinking right. Just STOP.
Save your money. Your electromagnet idea won't work. I am trying to give you advice here.
The pull rating you are quoting is holding force when in contact with ferous materials. It can lift that much, if in contact with, but it can't pull. Its an electromagnet. NOT a high powered solenoid, which you wouldn't be able to afford anyways.
Ian. Just stop bucking the system. Think man, THINK.
You won't go air, you won't go linear actuator due to cost and space and you won't go manual/lever type. So now you think electromagnets???? You have no concept of the theory and application of electromagnetism.
Don't you have anything better to do, like your prototypes of whatever???
Forget all and any electric power plunger/draw bar. Unless they are specifically engineered for that particular tasks, it's just throwing more crap on the mill and more money out the door.
Don't you ever learn??? Everyone has told you to smarten up, and just go air, or go manual lever type. It's simple, quiet, takes the least amount of room and is inexpensive. You, with all your years as a machinist, could have this done in a day instead of trying to reinvent the wheel.
Please if you won't take advice on this subject, then Stop filling this thread with your failed idea. It was a faillure from inception to conception and Defeng the all mighty engineer was stupid to even think it would be reliable enough to implement on his machines. As an electrical/electronics "wizard", the use of a 12Vdc motor at 36Volts is just stupid. But he did it to make a sale and please the ignorant.
Move on and do something different.
.

[handlewanker]

Yeah Yeah, ...blah blah...whatever.......when I stop thinking of alternative ways to do something I'll stop living......my motto is "there has to be a better way".

With hindsight the actuator design did have some drawbacks mainly due to adapting an existing device for another purpose and it's availability, but so did the first A bomb, but nobody stopped "improving" it to where it is today.

BTW....you are wrong on the magnetic attraction aspect........the armature, or the steel plate that does the pulling when the magnets activate, gets a huge magnetic force applied to it as the gap distance is approx. 5mm at most.

You can test this force with a 32mm diam Neodimium magnet by holding it 6mm away from a steel object.....if you can.....the attraction is mind boggling...... the closer it gets the stronger the pull........in case you didn't know that.

The initial movement of the armature, under a no load situation, is to take up the slack or clearance.......the actual unlocking move occurs at the last moment over a distance of 2mm to unlock the tool, and this is where the greatest force will occur.

Each of the electro magnets I mentioned has an attraction force of 80 Kg at the end travel and even if that is when it's in contact with the steel plate, just the initial 5mm proximity is enough to justify the design concept.

With 4 of those magnets you get 320 kg's of pure brute force for a total power consumption of 1.6 amps at 24 volts.......whew, my electricity bill will be .........miniscule...LOL......compare that to a small hobby compressor with a 1 HP motor chugging away for a few minutes to fill the tank.

When I get to making prototypes with the CNC method I'll post them here to show that the system as I envisage it can work......what other people do is their joy....I didn't buy the mill to justify it's cost......you can't put a price on satisfaction.
Ian.

[handlewanker]

Hi, I just did some design calculations to mount 4 electro magnets inside the actuator housing on top of the existing PDB mounting body.

The existing PDB housing will have to be re-made as the 4 magnets are each 65mm diam and the inside of the existing housing is only 115mm wide........no big deal as it's only a few pieces of 3mm thick steel plate welded together with a socket for the power plug and a switch.

The height of each magnet is only 30mm, so it will have an ultra low profile.

Perhaps the magnet housing could be 170mm in diam instead of 120mm square.....this would reduce the amountof welding by using a piece of available tubing, but I like the idea of the square box on top

BTW.......as an offshoot, these magnets could also be used to make a very powerful chuck either for vertical or horizontal clamping at the flick of a switch......at A$35 each.
Ian.

[G59]

Please start your own thread then. I'm not watching this thread because of you. I'm interested in the other SVM owners and what they do. Specifically Louie an Jips.
You everytime hijack it to put out the absolutely, most ridiculous ideas out there. I'm sure some watch this thread just to read about them and get there morning laughs.

You probably don't even know how to start a thread so that would explain things a little.

[LeeWay]

Hi, I think you confuse simplicity with practicality........on that basis a wrist watch is a desirable item but it's complicated.........you could adopt the idea of simplicity and have a small sun dial on your wrist bit that's not practical.

Just remembered a joke.......the first practical wrist watch for time estimation was invented over 3 thousand years ago by Alexander the Great.

In one battle it was vital to start the battle at the time when the sun was at it's highest or midday.......so Alex wrapped a piece of cloth around his wrist doused with a solution of a secret substance that turned black when exposed to strong sunlight.

In recorded history, this became know as "Alexander's Rag Time Band".......LOL.
Ian.

That has just been my observation from your ideas and posts in this thread. Thinking up new ways to do stuff is not a bad thing, however before you can really improve on a thing, you have to know how that thing works to start with. What will your idea do better or what problem will it address?
Is it just stubbornness that is driving you to do something different? (Not necessarily a bad quality for inventors) Inventors do usually learn to use tools that would really help you immensely. That is learning to use CAD.

[G59]

Is it just stubbornness that is driving you to do something different? (Not necessarily a bad quality for inventors)

It is if it leads to nothing and it won't improve anything==waste of time.

He doesn't take advice or do any calculations before opening his mouth. No respect and doesn't listen to engineers or to anyone that has more than just an idea on the topic.
Take for example, how much pressure is needed to release the tool? He is only guessing at the number. No actual specs. There are linear actuators on Ebay that push 500-700 pounds and have 50mm stroke for $100 bucks. But he knows better and decides his way is so much better.

Imagine living with such a person.

Weird................

[Tkamsker]

Morning laugh is important but You are Right he should do His own Thread and i watch because i payed a lot for that ...


Gesendet von iPhone mit Tapatalk