To flame cut or not to flame cut, which is the better option in A36 steel

[memphisjed]

Insane markup for any cutting if qty is one.
Yes, do 2 inch plate at least twice a month.

 

[gbent]

Any particular reason it isn't a fabrication?

 

[EmGo]

Any particular reason it isn't a fabrication?

Fools rush in .... how about go all the way ?

https://files.catbox.moe/o59bkm.mp4

 

[memphisjed]

Fools rush in .... how about go all the way ?

https://files.catbox.moe/o59bkm.mp4

Forging those ears would be… not fun.

 

[EmGo]

Forging those ears would be… not fun.

I was thinking about this ... some people do crossword puzzles, others think how to forge steel

It might not be that bad. The arms are no biggy. Step one could be a straight shape with a lump in the middle where the tangs are. Step two bang it down to bend the arms. Step three set on edge and bang the whole shape except for the space between the tangs which stays solid. Step four, pierce between the tangs with a square pin instead of a round one like you'd use for a bore.

May or may not work but better than wondering what's a seven letter word for an arachnid native to iceland.

 

[just Dave]

I haven't ordered the material yet so it sounds like I should add at least .100" per side for them.

It also wouldn't hurt to do multiple roughing passes to help with any stresses that get released.

Does anyone have recommendation for a better way to hold it to be able to get at both sides of the profile at the same time? My other thought was buying some large pitbull clamps to be able to face+rough the top half, then flip it around and repeat before going on to finish it.

No matter what, you will likely need to straighten the finished parts back into shape after milling unless you baby each one like a nasa job. Not a big deal but likely. If you bend those 2” square HRS A36 bars, you could do that in a 50 ton press cold and weld a machined clevis into a notch you would mill into the bent bar. The part looks like a yoke that bolts to an attachment chain of some kind for a conveyor of some sort.?? Not high precision.. you may need to bend a couple long and saw end to length to zero in on perfect length. I have done a bunch of bending of this type in a 50 ton H frame. A power pump is worth every penny.

 

[Mr.Chipeater]

No matter what, you will likely need to straighten the finished parts back into shape after milling unless you baby each one like a nasa job. Not a big deal but likely. If you bend those 2” square HRS A36 bars, you could do that in a 50 ton press cold and weld a machined clevis into a notch you would mill into the bent bar. The part looks like a yoke that bolts to an attachment chain of some kind for a conveyor of some sort.?? Not high precision.. you may need to bend a couple long and saw end to length to zero in on perfect length. I have done a bunch of bending of this type in a 50 ton H frame. A power pump is worth every penny.

All I've got is a harbor freight press. Would that get the job done?

In all seriousness, I heard back from the heat treater and its only $150 to stress relieve them so even if it only helps marginally, it sounds like it would be worth it. I could throw the blanks on the surface grinder first to at least make sure there's no distortion from clamping but without any previous A36 experience, it looks like it will be a learning opportunity.

As drawn, they want to hold .010 on the length of the arms which normally is wide open for us but if the arms start bending and moving all over the place on us, I could see that quickly becoming an issue to hold.

 

[just Dave]

All I've got is a harbor freight press. Would that get the job done?

In all seriousness, I heard back from the heat treater and its only $150 to stress relieve them so even if it only helps marginally, it sounds like it would be worth it. I could throw the blanks on the surface grinder first to at least make sure there's no distortion from clamping but without any previous A36 experience, it looks like it will be a learning opportunity.

As drawn, they want to hold .010 on the length of the arms which normally is wide open for us but if the arms start bending and moving all over the place on us, I could see that quickly becoming an issue to hold.

It would not be uncommon to have to bend a part back into shape after machining. If you toe clamp and mill portions , add toe clamps before releasing and finish milling. Now it is the correct shape and tolerance. If it springs in some way you can straighten it. If you mill part and release it will have to be straightened before you mill the rest eating away at your tolerance. It would be help full to Blancher grind both sides before machineing to releave stress. Some big burn shops offer that service. Do you have the thickness to loose? A surface grinder to descale flame cut plate sounds like eternal hell.
Hydraulics are strictly pressure no matter who made it. You will get some swell at the bend that may need grinder clean up or milling. Keep in mind that often times a Buyer has no idea what a part does or where it goes .

 

[Mr.Chipeater]

It would not be uncommon to have to bend a part back into shape after machining. If you toe clamp and mill portions , add toe clamps before releasing and finish milling. Now it is the correct shape and tolerance. If it springs in some way you can straighten it. If you mill part and release it will have to be straightened before you mill the rest eating away at your tolerance. It would be help full to Blancher grind both sides before machineing to releave stress. Some big burn shops offer that service. Do you have the thickness to loose? A surface grinder to descale flame cut plate sounds like eternal hell.
Hydraulics are strictly pressure no matter who made it. You will get some swell at the bend that may need grinder clean up or milling. Keep in mind that often times a Buyer has no idea what a part does or where it goes .

Would it make more sense to blancher grind or stress relieve or both? They do offer it so I'll see what it costs.

 

[just Dave]

Both

 

[Mr.Chipeater]

Are you supposed to stress relieve before or after grind? I would have though before, but the material supplier quoted after. I was going to have them grind to final thickness but now I'm thinking it will be better to leave a little extra so there's room in case it warps from stress relief.

Price went from $2800 to $4500 to add grind and stress relief but I think it will be worth it if it saves a lot of machining headaches

 

[just Dave]

After grind because pealing the skin will induce stress. It will be more on one plane if it moves. The flatness required across a part this size is a significant factor. If they want .010” flat end to end you will likely need to mill that. You need to communicate to the grinder the flatness you’re looking for up front. It could require a couple flips on the Blanchard to get what you need.

 

[just Dave]

How many of these are you making?

 

[Dan from Oakland]

Silly question, but have you asked your customer if the arms need to be machined at all? or even just a portion of them for functionality.

 

[EmGo]

Hmmm. The numbers for this are getting up to where you might consider getting a quote for castings ? It'd be pretty simple to cast, altho steel kinda sucks at casting.

 

[Mr.Chipeater]

How many of these are you making?

35 of them

Silly question, but have you asked your customer if the arms need to be machined at all? or even just a portion of them for functionality.

customer wants machined surface on all sides.

If I'm still going to have to deal with flatness issues after grind, is it even worth it compared to just taking a skim cut on both side before stress relief? Stress relief is only $200 so most the added cost is in the grinding.

 

[EmGo]

Just for fun I took a quick look around and came across this ....

MMI_Home - Monett Metals Inc.

Monett Metals is a specialty steel casting foundry specializing in carbon-based and stainless steel castings, investment castings, heat resistant castings

monettmetals.com

worth a phone call ? It might be interesting to see how this compares ....

 

[eKretz]

Silly question, but have you asked your customer if the arms need to be machined at all? or even just a portion of them for functionality.

I figured it was either called out on the print or that he had already asked that question. But that's a good point.

 

[just Dave]

If s go on forever , bid high learn a lot