080a15 bright mild steel

[6ply]

Next task will be to drill, tap and cut into half lengthways, making 4 t-nuts in total.

My conclusion so far is this material machines nicely.

 

[ukracer]

Next task will be to drill, tap and cut into half lengthways, making 4 t-nuts in total.

My conclusion so far is this material machines nicely.

View attachment 422383

Which leads us to.ask.how much for 10 blocks posted.

 

[6ply]

Hand tapped ok, though noticeable harder than en3.

Had to hit the number stamps hard to make a good impression.

 

[6ply]

 

[Laurie Tedcastle]

View attachment 422489

Nice! 1 more job if you haven't already - distress the threads on the underside of each nut, so the stud cannot go right through and possibly break the tee slot.

Laurie

 

[6ply]

Nice! 1 more job if you haven't already - distress the threads on the underside of each nut, so the stud cannot go right through and possibly break the tee slot.

Laurie

Already done. I used a centre punch to close the thread.

 

[Laurie Tedcastle]

Already done. I used a centre punch to close the thread.

That's as good a way as any I think. Some on here just may not know the importance of doing it.

Laurie

 

[ukracer]

That's as good a way as any I think. Some on here just may not know the importance of doing it.

Laurie

Like me for example.

 

[Hopefuldave]

Ever seen a mill or a lathe cross-slide with the T-slots gaping like a speedfreak's teeth? That's the importance - if you wind the hold-down studs right through the T-nut you put the edges of the slots under pressure in the wrong way and snap 'em off - the idea is the T-slot edge is clamped between the T-nut and the work, overtightening the stud jacks the nut out of the slot and ping...

Both ugly and sad, isn't it? Have you ever seen such cruelty?

 

[Laurie Tedcastle]

Ever seen a mill or a lathe cross-slide with the T-slots gaping like a speedfreak's teeth? That's the importance - if you wind the hold-down studs right through the T-nut you put the edges of the slots under pressure in the wrong way and snap 'em off - the idea is the T-slot edge is clamped between the T-nut and the work, overtightening the stud jacks the nut out of the slot and ping...

View attachment 422659

Both ugly and sad, isn't it? Have you ever seen such cruelty?

Thanks for posting such a good illustration. Many do not realise just how weak cast iron tee slots are.

Laurie

 

[Hopefuldave]

Thanks for posting such a good illustration. Many do not realise just how weak cast iron tee slots are.

Laurie

Welcome - it's damage that's easy to avoid, damn hard to repair... A whack with hammer and cold-chisel to the end of the threads as mentioned by Laurie does the job, or a spot of weld in the thread (my preference) will save the cruelty happening!
I'm pleased to say the pic isn't of any of my machines, but it still makes me cringe just seeing it...
Also I should stress that crap in the T-slots is a Bad Thing, as anything between the surfaces of the slot and the nut can concentrate the force of tightening on a very small area and cause damage too - so keep it clean, folks!

 

[Windy Miller]

…Both ugly and sad, isn't it? Have you ever seen such cruelty?

Unfortunately yes I have. This is my mill/drill table. I hasten to add that I’m not responsible for any of this carnage - it’s how I bought it.

So far it’s not been an issue for me as I do 99% of my milling in the vice, but I’m sure one day it will be a problem!

 

[Wedg1e]

At work, we supply reference blocks used for calibrating ultrasonic flaw detectors/ thickness gauges and our usual carbon steel ones are 080A15.
Historically we'd have them surface ground but the CNC shop we use gets them to better than 0.8um surface roughness off the cutter, saving a fortune in time/grinding.