Hands up if you think flat bar should be flat

[2volts]

A 6" vise is overkill for a RF45 style mill. A 4" is more appropiate for that size mill & IMO 5" max. I have a 5" GMT vise on my PM45 & it's slightly too big. Not enough Y axis travel to make use of the 5" full capacity. Better to save your money rather than getting something too big & most importantly the weight. I take my vise of the table quite often, a 6" is still light enough for me to be carried by hand but I'm glad I have a 5". I also have a 4" vise as well. I prefer the 5" though.

But those GMT 6" Premium vises are pretty nice. I'd love to have one but don't need one on my current mill. But if you plan on upgrading to a full size knee mill in the future than the 6" will be perfect.


Here's what the 5" looks like on my mill.



I couldn't even complete this cut without my bellows & DRO scale getting in the way. Not enough Y travel & the 5" vise is not even maxed out.



Here's what a 6" vise looks like on another PM45 (gt40's)
View attachment 253544

 

[Kiwi]

is it all like that i've seen it like that at the ends of a length

 

[2volts]

yes. whole 2m. also looked at some stock at the store today and it was the same.

 

[cvairwerks]

Just depends on your definition of "flat"

 

[Firestopper]

If you want "flat" flat bar, you might start off with cold rolled (CR). CR will also be correct in size unlike hot rolled that varies a bit in dimensions.

 

[ewkearns]

I agree with the other posters, but I have to say that stuff is junk. Any machine shop denizen, tasked with purchasing duties, will have their own particular set of horror stories.... especially with export materials produced in some countries.

Maybe a new thread on "the best places to obtain materials?"

 

[Cobra]

I have often received the same form of flat bar in Canada when buying those small sizes. It is usually fine for projects that I am welding up frames etc. I am with Paco, if you need mostly flat, use cold rolled, if you need flat flat use precision ground stock.

 

[RJSakowski]

It has been my observation that for HR bar, flat is used as a descriptor to distinguish from squares or rounds. HR is mainly used for welding fabrication where precision is not required. Given the nature of its manufacture, it is not realistic to expect a precision surface. i.e., don't expect dimensional accuracy, flatness, squareness, roundness,or straightness from a piece of HR steel.

 

[sgisler]

Looks like what you have there is sheared flat bar, actually sheared from plate or sheet. Very common in stainless 'flat bar'. Hot rolled flat bar is pretty flat across its width and has somewhat rounded edges (variable with thickness; thicker bars have flatter edges). As others mentioned, if you want good size, good square edges, sharp corners in steel, get CRS. True HRS would be next step down in cost/quality. Sheared bar generally at the bottom of the scale of cost/quality. Bonus with CRS is no 'bark' or scale, it's nice and smooth.


Stan
Sent from my iPhone using Tapatalk

 

[kvt]

Agree with Stan That looks like sheared stuff. Find that stuff in places like Lowes and Home depot around here. there are a couple of steel suppliers that sell the good stuff and often at a better price per foot than you pay the box stores. But they are not as handy at times.