Punch or cut a 1/2" deep x 0.125" wide side-slot in 0.080" 5052 AL

[The Dude]

I need to develop a process with a dedicated fixture/machine (only does this) to make the notches shown in the drawing below. For prototypes, yes, it was easiest to get laser-cut parts. For the future higher volumes (not huge), it will be way cheaper to get the straps sheared (via supplier) and then hopefully an easy way to put in the notches, one on each end as shown. They will only be doing these about once/week and it's around 50-100 week. So here's some factors:

• Since it's not a huge volume, and limited floor space, fine to do one end at a time (grab a strap, slot one end, flip it, slot the other end, put it on the finished stack and do the next one).
• I can see it as either "slitting" with a slitting blade (about 2" dia. x 0.125", shown in the drawing below) or punching in hopefully a pneumatic punch. I would prefer punching since it can easily be made quick and safe, where you just slide it into a narrow opening (can't put your fingers through the guard), maybe a limit switch to ensure it's in deep enough, and cycle it. The slitting would possibly be easier and cheaper to design & make the machine but it would need to be clamped and fed (either the slot of the slitter blade). Might be better to clamp about 10 straps at once and feed the blade though, like you're cutting a slot in thick aluminum).
• Should be able to get sufficient tonnage with at least a 6" diameter cylinder to do punching, probably go 7 or 8 to ensure.
• If we did go with slitting, would like to do it in a manner that wouldn't allow the aluminum to gouge-up on the blade, which those slitter blades seem to do with soft aluminum (might do better on the 5052 that they do on soft extrusions on another process I made to slot the end of an extrusion and we might hopefully change that to punching if we can make this process work).

Main question is, if you agree that the punching would be best, is there someone you could recommend for the tool and die? If cutting/slitting with a blade, is there a particular blade supplier you could recommend that might be able to supply a carbinite or some other type of blade that would cut through better than just "hard steel". If you have any other general recommendations, let me know.

Thanks,
The Dude

 

[atex57]

Do you have an arbor press or small punch press? If you do, a simple die set to punch the slot in a bump style die shoe set.

Ed.

 

[The Dude]

Do you have an arbor press or small punch press? If you do, a simple die set to punch the slot in a bump style die shoe set.

Ed.

Wow, didn't even think about an arbor press but looked online and you can get a 2 ton (we are just over 1 ton) really cheap and that might work great! I do need to determine the qty and batch size (not all in one cycle, just how many when they make them, can't have it be too physical for too long). Do you know a supplier who could make the punch for it?

Thanks,
The Dude

 

[dkmc]

Wow, didn't even think about an arbor press but looked online and you can get a 2 ton (we are just over 1 ton) really cheap and that might work great! I do need to determine the qty and batch size (not all in one cycle, just how many when they make them, can't have it be too physical for too long). Do you know a supplier who could make the punch for it?

Thanks,
The Dude

You could maybe cook up a punch in house? For Alu. mild steel not even hardened would probably do the job. It's not much material to remove, 'tonnage' is pretty low.

 

[TKassoc]

Buy a used unipunch frame off eBay and have them make you a die set. Better yet by three and make the whole part complete with two notches and one cutoff from strip.

Punching Holes in Aluminum Extrusions | UniPunch

UniPunch tooling is commonly used for punching holes in aluminum extrusions up to 1/4" thick and will punch a variety of shapes into the metal.

unipunch.com

 

[Garwood]

I would punch it. If you need help with a tool build for this I'm near Portland and could do it.

I would be inclined to use air or a benchmaster instead of an arbor press. Employees will hate the arbor press pretty quick doing 100 pcs a week.

 

[Limy Sami]

A simple wood jig and a carbide blade on a table saw, gang em up @ <> 20 a time ?????

 

[Garwood]

A simple wood jig and a carbide blade on a table saw, gang em up @ <> 20 a time ?????

That's a great idea. A chop saw with a metal blade dedicated fixture/stop would do that slot fine.

 

[specfab]

Table saw would be my vastly preferred method, assuming I'm smart enough to keep my fingers out of the blade. Not sure that applies to a lot of the work force these days.

 

[Garwood]

Table saw would be my vastly preferred method, assuming I'm smart enough to keep my fingers out of the blade. Not sure that applies to a lot of the work force these days.

Tablesaw sounds good. After the first lawsuit they won't have to worry about making these parts anymore.

 

[The Dude]

Hey thanks all, I think I have enough responses to look into it. I am going to put an emphasis on a pneumatic punch, and would be nice to do a pair at once, that could work out good.

Thanks again,
The Dude

 

[rogertoolmaker]

I need to develop a process with a dedicated fixture/machine (only does this) to make the notches shown in the drawing below. For prototypes, yes, it was easiest to get laser-cut parts. For the future higher volumes (not huge), it will be way cheaper to get the straps sheared (via supplier) and then hopefully an easy way to put in the notches, one on each end as shown. They will only be doing these about once/week and it's around 50-100 week. So here's some factors:

• Since it's not a huge volume, and limited floor space, fine to do one end at a time (grab a strap, slot one end, flip it, slot the other end, put it on the finished stack and do the next one).
• I can see it as either "slitting" with a slitting blade (about 2" dia. x 0.125", shown in the drawing below) or punching in hopefully a pneumatic punch. I would prefer punching since it can easily be made quick and safe, where you just slide it into a narrow opening (can't put your fingers through the guard), maybe a limit switch to ensure it's in deep enough, and cycle it. The slitting would possibly be easier and cheaper to design & make the machine but it would need to be clamped and fed (either the slot of the slitter blade). Might be better to clamp about 10 straps at once and feed the blade though, like you're cutting a slot in thick aluminum).
• Should be able to get sufficient tonnage with at least a 6" diameter cylinder to do punching, probably go 7 or 8 to ensure.
• If we did go with slitting, would like to do it in a manner that wouldn't allow the aluminum to gouge-up on the blade, which those slitter blades seem to do with soft aluminum (might do better on the 5052 that they do on soft extrusions on another process I made to slot the end of an extrusion and we might hopefully change that to punching if we can make this process work).

Main question is, if you agree that the punching would be best, is there someone you could recommend for the tool and die? If cutting/slitting with a blade, is there a particular blade supplier you could recommend that might be able to supply a carbinite or some other type of blade that would cut through better than just "hard steel". If you have any other general recommendations, let me know.

Thanks,
The Dude
View attachment 390681

The tonage required to punch the slot in 5052H32 figures 1.35 tons.
Roger

 

[FamilyTradition]

The tonage required to punch the slot in 5052H32 figures 1.35 tons.
Roger

Roger, I have wondered about how necessary tonnage for press operations is calculated. What formulas/tables did you use? Is that something I would find in Machinery's Handbook, or more of something you have learned to estimate through experience gained over the years?

 

[Erich]

Material maximum shear strength times the length of the perimeter of the punch times the thickness. AKA cross section area being sheared times strength.

 

[Overland]

Would there be any risk of distortion in the material from punching ?
The slot seems fairly close to the end.
Bob

 

[Limy Sami]

Would there be any risk of distortion in the material from punching ?
The slot seems fairly close to the end.
Bob

That was one of my thoughts too - while it's not my field, I'd have thought if punched the part is going to have to be firmly clamped either side of the slot.

 

[just Dave]

A simple wood jig and a carbide blade on a table saw, gang em up @ <> 20 a time ?????

Right on the nose Limy. Former shop I ran had two big table saws. On set up for ripping and one for crosscutting. We had a full width miter gauge fence with stops. This job looks like a 5 minute set up and about six parts per minute before de burr.
We ran tons of plastic on the saws.

 

[The Dude]

I'm checking in on some things. Pretty sure there could be a side-gauge/clamp to keep the end from distorting, but it would be okay for it to do a bit as long as it's structurally sound. Got plenty of into...thanks!

The Dude

 

[Limy Sami]

I'm checking in on some things. Pretty sure there could be a side-gauge/clamp to keep the end from distorting, but it would be okay for it to do a bit as long as it's structurally sound. Got plenty of into...thanks!

The Dude

Okay, you seem to be looking at punching ( not, you know how I would do it) but be wary of costs of your solutions, press tooling ain't cheap, over 50 years experience with jobs like this has taught me things change (for all sorts of reasons - usually completely out side your control) and your big $ tooling is suddenly obsolete.

Which will leave you right behind the 8ball, because if you run your own show, it can leave you severely out of pocket, or having to answer to company bean counters, etc etc

 

[rogertoolmaker]

Okay, you seem to be looking at punching ( not, you know how I would do it) but be wary of costs of your solutions, press tooling ain't cheap, over 50 years experience with jobs like this has taught me things change (for all sorts of reasons - usually completely out side your control) and your big $ tooling is suddenly obsolete.

Which will leave you right behind the 8ball, because if you run your own show, it can leave you severely out of pocket, or having to answer to company bean counters, etc etc

Amen. Cut the slots with a carbide saw blade on the table saw to get to job started. When requirements become large enough then go for improved methods. The cleanest way would be to punch the slots. However, the annual quantity needs to justify the cost.