brake press basic operation/tutorials

[schiada96]

Originally Posted by la_coterie hi Schiada96 Depends what material and what size Vee and what shape punch and what way the wind blows. What I'm basically saying is that you can get a rough size from calcs which are normally good enough. but if you want it spot on test with a piece of the sheet you're goning to use Our favourite for sheet - i.e, 3mm & less inside dims added up - works for us on mild steel in 8x mt Vee

The formula is north american avations. You make the material form to the inside radius you want not what it wants. I have found this formula to be best and consistent to within .002.
Jeff

[la_coterie]

Aircraft sheet metal now that's further up the food chain and your material is better quality

[bob mascaro]

i agree .. i get so tired of aaarguing with people over microns ..lol .In sheetmetal the thickness varis more than bend allowances not to mention coinage are concerned .
Its bend dedution and twice the metal thickness is the answer. Bob ie the solidworks guy with 20+ yrs fab exp.

[la_coterie]

Cor more than year since this was last aired!

Strange that the originator of the question hasn't posted any more, maybe he was a troll. Not the most obvious thing to start an agrument on though.

Yeah Bob, I agree. how big is a micron anyway

If you need it that acurate the design must be crap, or go and machine it out of a lump of solid!

I dunno what your sheet tolerances are across the pond, I guess the same as UK +/- 10%

You know sheetmetalworkers are miracle workers really

[schiada96]

Originally Posted by bob mascaro i agree .. i get so tired of aaarguing with people over microns ..lol .In sheetmetal the thickness varis more than bend allowances not to mention coinage are concerned . Its bend dedution and twice the metal thickness is the answer. Bob ie the solidworks guy with 20+ yrs fab exp.

Beg to differ but your formula will be wrong with a insde radius of .03 by about 1/16 on .125 thick material. Tell me what solidworks comes up with for .125 thick material on with a inside radius of .75.
And if your material thickness is varies that much please find a new suppiler. You are talking about thickness variences of .100?

[bob mascaro]

see thats what im talking about lol. and by the way what kind of repeatability do u expec to get with a 3/4'' radi on 11 guage ,surley u dont expect to hold that flange length anywhere near std. tolerances unless its only a few feet long? try stamping or coining maybe.

[bob mascaro]

the formula is for right angle 90 degree bends u have to go into bend allowances for more acute or obtuse bends

[bob mascaro]

actually its called a brake because it has a brake just like a car or at least the old ones did (conventional) . there was a fly wheel that actuated the ram
some peeps called it a clutch so we could also call it a clutch press if we wanted to . Even the hydraulic press have whats called a brake valve

[3d Laser]

Hi Guys, this is our first time to writing here.We bought LVD Brake press with MNC 800 controller. We found three big cards not working, please if anyone can help us to find those card that would be great help.
Thanks

[bob mascaro]

yes thats correct but u can also use k-factor or bend deductions and allowance . but the point is that unless your bending plate or building space ships comprised of titanium lol its a waste of time,but now if your useing a
3d programs like SolidWorks i go ahead and use allowance

[PhoenixMetal]

Originally Posted by 3d Laser Hi Guys, this is our first time to writing here.We bought LVD Brake press with MNC 800 controller. We found three big cards not working, please if anyone can help us to find those card that would be great help. Thanks

Press brake backgauge controls are notoriously unreliable (at least the old ones are). There are many companies that will repair the boards for you, typically at a cost of $1,000 to $1,300 each, but the sad fact is that within a short period of time, those same cards (or other ones in the same system) will fail again.

My solution has been to replace the electronics with my own and I write a program on the computer to control them. I used a controller from Galil on one system, and a controller from Anaheim Automation on another. If you know how to do this (or can figure it out), you can replace the controls with your own for around $1,200, and will be much happier for it.

The PC controlled solution is also superior in many ways - for example, its much better in my opinion to be saving the part files on your computer than it is to save it on a proprietary control mounted on the machine.

This solution can also be much more intuitive for the machine operators. For example, I have my systems output to the monitor "Bend 1, Burr up" "Turn part 90 degrees" etc, and have also translated the instructions into Spanish when needed.

So in my opinion, when your press brake backgauge controls break, don't fix them. Replace them.

[jmkelkar]

Hello, I have a bit of a basic question. I have seen that when we bend a long sheet about 4 mm thick at right angles for a small length sheet length 3 metrs and fold length 55 mm., we need a huge manpower ( about 12 persons) t0 Throw up the 3 meter lenth of the sheet up in the air to facilitate the bend as the ram bends.

Is this the correct method? Is there any mechanical arrangement to lift the sheet as bending happens? I am curious to know this.