Material to make studs – EN1A??

[flatlineParticipant @flatline]

Firstly my apologies -as a similar question has recently been asked… However, my application is slightly different & I am very much a newbie, so…

 

I am running a Myford Super-7, and am upgrading the vertical-slide and vice to some newer more rigid items. I have bought some T-slot blanks, and would like to turn some studs to bolt the vice to the vertical-slide… As has been mentioned elsewhere I also have to hand some EN1A, which I can turn down to 7mm-dia to match the mounting holes in the vice, and then cut threads to attach to the T-slot blank & then use suitable nuts, washers, etc..

 

So my question is will EN1A have sufficient tensile-strength in this application?? I accept that it would be fair easier to go out and buy some bolts/studs ‘off-the-shelf’, but the idea of manufacturing my own parts to suit has far more appeal.

 

Many thanks in advance for any advice.

 

 

[SillyOldDufferModerator @sillyoldduffer]

Yes, go for it.  Though not a strong steel a 25mm diameter EN1A rod will support a weight of about 15 tons, plenty enough for studding on a lathe.

I expect you know of the need to ensure the thread end of a t-nut should be dinged to stop studs jacking them?   If jacking happens the stud can break the lathe slots because cast-iron is weaker than EN1a.

EN1A is unsuitable when safety matters.  Brakes and such need a higher safety factor, better corrosion resistance, and cut threads are relatively weak too.   As your lathe application isn’t safety critical, EN1a is OK.

Dave

 

 

[flatlineParticipant @flatline]

Dave,

 

thank you for your reply… I am a newbie, so not sure what you mean by “the thread end of a t-nut should be dinged to stop studs jacking them”…

Also, I am planning to run the T-slot ‘blank’ the full length of the slot (approx 4”) to spread the load a little… If you think this would help??

[howardbParticipant @howardb]

EN1A, also known as 230M07. EN1A is low carbon mild steel. Properties: free cutting, suitable for machining using both automatic and CNC machines.

Not suitable for bolts, studs etc it’s soft , not tough enough.

If you must make studs use something like EN8.

EN8 also know as 080M40. An unalloyed medium carbon steel. EN8 is a medium strength steel, good tensile strength. Suitable for shafts, stressed pins, studs, keys etc.

Or buy lengths of studding 8.8 grade,usual sizes are even numbers 6,8,2,10, 12 etc.

Or buy 8.8. or 10.9 grade hex head machine screws and modify the heads so they fit in the tee-slot.

[Julie AnnParticipant @julieann]

I am using EN3B for all the studs on my scale traction engine, as it is commonly used on full size engines:

It is much less prone to rust than EN1A.

Julie

[Charles LamontParticipant @charleslamont71117]

I disagree with Howardb. In the application as T-slot bolts no great strength is required and EN1A will be perfectly adequate.

[flatline]

On flatline Said:

Dave,

 

thank you for your reply… I am a newbie, so not sure what you mean by “the thread end of a t-nut should be dinged to stop studs jacking them”…

Also, I am planning to run the T-slot ‘blank’ the full length of the slot (approx 4”) to spread the load a little… If you think this would help??

Having full length T nuts probably doesn’t spread the load much, but certainly makes for easier assembly.

Re. dinging the threads; consider the T nut this way up  ╩ with a threaded through hole, and slid into a T slot on the cross slide.
If you can screw a stud or bolt all the way through, such that it presses against the bottom of the T slot, then it’s possible to exert so much force that you break a lump of cast iron from the top of the T slot.
Personally, when the hole has bee threaded, I just invert the nut and use a wide punch to damage the end few threads of the threaded hole.
That way the stud has enough engagement, but doesn’t push the nut upwards when the vice isn’t present.
When tightening the normal hex nut onto the stud to bolt the vice or slide down, tightening hard is less of an issue, as you are pulling the ╩ nut upwards against the body of the vice, which supports the top of the slot.

Bill

[Andrew CrowParticipant @andrewcrow91475]

I tend to shorten one end of my studs so that they can’t protrude through the bottom of the tee nut.

However, the greater risk is from using bolts which if too long will cause the problem.

Andy

[JasonBModerator @jasonb]

I’d just use 4 cap heads or bolts for that job rather than fiddling with studs, washers and nuts. Make the length so they don’t bottom out.

[JasonB]

On JasonB Said:

I’d just use 4 cap heads or bolts for that job rather than fiddling with studs, washers and nuts. Make the length so they don’t bottom out.

That’s what I thought. 4x m6 cap heads would do.

[John HaineParticipant @johnhaine32865]

I use stainless studding for all my clamping except for the M8 and M10 studs that came with a couple of clamping sets.  Why make life difficult?

[Nigel Graham 2Participant @nigelgraham2]

John-

You and I would do that, well studding anyway, not necessarily stainless, but Flatline said he wants to make his!

[FulmenParticipant @fulmen]

I would strongly discourage the use of soft steel bolts. One can of course use any material as long as you treat it within it’s limits, but that’s also the problem. Most bolts are strong, that makes it much easier to over-torque soft ones. Also, this is meant for repeat use. Soft steel wear fast.

[Geoff RogersParticipant @geoffrogers81118]

For the traction engines I am making (4″ Burrells) EN8 is being used for the majority of bolting/studding.  Would not use anything of lower grade.

[Neil AParticipant @neila]

Up until the introduction of metric threads in the 1970’s it was quite common for standard studs to be produced in EN3B (070M20) 28 tons/in2 min, usually cold drawn. With the use of metric threads the material went to 8.8 grade, equivalent to an “S” grade 50 ton/in2 in the old EN system.

What material you use for your studs depends on what you expect of them. With the lower grades of steel you will not be able to achieve the same clamping force as the higher grades. As has been pointed out, it is easier to strip the threads on the lower grade materials, particularly if you are used to using the 8.8 grade fasteners.

The old EN3B studs were usually only tightened once when the parts were assembled, repeated assembly and disassembly will in due course wear the lower grade material and increase the possibility of stripping.

If you do decide to machine your own studs, I offer one word of caution. Do not reduce the diameter of the bar too much from its as drawn state, the core of the material may not have the same properties as the outside diameter. This applies to all steel bars, particularly if they have been hardened and tempered to a specific condition.

Neil

[Neil A]

On Neil A Said:

Up until the introduction of metric threads in the 1970’s it was quite common for standard studs to be produced in EN3B (070M20) 28 tons/in2 min, usually cold drawn. With the use of metric threads the material went to 8.8 grade, equivalent to an “S” grade 50 ton/in2 in the old EN system.

What material you use for your studs depends on what you expect of them. With the lower grades of steel you will not be able to achieve the same clamping force as the higher grades. As has been pointed out, it is easier to strip the threads on the lower grade materials, particularly if you are used to using the 8.8 grade fasteners.

The old EN3B studs were usually only tightened once when the parts were assembled, repeated assembly and disassembly will in due course wear the lower grade material and increase the possibility of stripping.

If you do decide to machine your own studs, I offer one word of caution. Do not reduce the diameter of the bar too much from its as drawn state, the core of the material may not have the same properties as the outside diameter. This applies to all steel bars, particularly if they have been hardened and tempered to a specific condition.

Neil

Neil, many thanks for your advice…dully noted

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