Sheet metal defaults

[sijcooke]

Hi all, any help would be very much appreciated on this... im pulling my hair out! Thank you in advance!

Ok, we use inventor to draw sheet metal parts of different materials and different thicknesses. We also have a CNC pressbrake which has different tooling on, e.g top tools have either 1mm, 1.5mm or 3mm radius... and the bottom tool V's are 10mm, 16mm, 24mm etc etc.

How is the best way to setup the sheet metal defaults?

On the press brake's bend table it says if i fold the same material, but to different angles, then i will get a different bend radius.. but in the sheet metal rules.. i have to set a bend radius... What radius should be put in here? This radius changes with the angle, so this bend radius should come from the bend table.. not a fixed value in the sheet metal rule?

Do i need each material and thickness setup as individual rules, and unfold rules for each individual material and thickness... do have a rule for each press brake tool i could possibly use??

Im very confused so any help would really be great.

Thanks very much,

Best regards, Simon.

[karthur1]

" How is the best way to setup the sheet metal defaults? "  

I would start with the most common thickness that you use.  Set the most common one as the default.

" On the press brake's bend table it says if i fold the same material, but to different angles, then i will get a different bend radius.. but in the sheet metal rules.. i have to set a bend radius... What radius should be put in here? This radius changes with the angle, so this bend radius should come from the bend table.. not a fixed value in the sheet metal rule? "

Inventor does not consider the press tooling other than the die that forms the bend. (inside die in most cases).  The radius that you should use for inventor (in most cases) would be the top die and is fixed for that bend.

"Do i need each material and thickness setup as individual rules, and unfold rules for each individual material and thickness... do have a rule for each press brake tool i could possibly use?"

That is entirely up to you and how accurate you need to be with the flat pattern lengths. I probably would start with each material thickness and just use the default .44 kfactor and set the iinside radius.  This will get you pretty close on the flat length.

Kirk

[sijcooke]

Thanks for your reply Kirk,

I will give this a go tomorrow, and see how i get on.

Best regards,

Simon

[blair]

The attached Excel spread sheet should help you.

If you have small as well as large angle bends and require extremely accurate flat layouts, using a bend table would be the best. At the same time you should be utilizing measured test strips for each of the bend angles and calculating the k-factor for each bend for each machine and die sets/bending methods.

[blair]

The attached Excel spread sheet should help you.

[sijcooke]

Thanks all for your messages. I think just a k factor and correct bend radius will work ok.

Thanks, Simon

[dlotti23]

The most important thing for real bending - V-opening of the die, internal radius based on it. Here is simple bending calculator. If any additional support necessary I can provide more