Bending 12mm square mild steel bar

[modeng2000Participant @modeng2000]

Hopper, I want to drop the head down so the tool bit is at a suitable height as per the Eccentric holder.

I have made a holder using the square hole method I described and it is fine. The problem is the tool bit is really too high leaving no room for adjustment. I really should reduce the shank thickness but unfortunately this holder does not have the off-set angle that the Eccentric diamond holder has.

Adding a drawing or photo isn't possible just now.

John

[Howard LewisParticipant @howardlewis46836]

The shop made tools clamp the toolbit in a slot, so that it can be set to centre height, jjust like the Eccentric Engineering one. Like the "Diamond" tool, the toolbit slot is angled relative to the body.

The published designs would make life much simpler for you, rather than trying to imitate the Eccentric Engineering forging.

If you want, no doubt some kind soul will tell you nwhich issue of MEW contained the two designs.

Howard

[modeng2000Participant @modeng2000]

Howard, Thanks for your input. A slot might be possible but it would have to suit the tool bit dimension while a V does not require a sized slot drill. I have tried to avoid a slot design for this reason.

Having tried various mock-ups it has become obvious that I can not make what I want from a 12mm square bar. I shall have to do as Jason suggested and cut the shape from a piece of 12mm thick strip.

Thank you all for this discussion, it has really helped me to understand what I am trying to do.

John

[HopperParticipant @hopper]

Either that or cut the shank and weld it at the required angle. Welding will be strong enough, where silver solder would not be. Local welding shop might do it for you for a few beer tokens.

[modeng2000Participant @modeng2000]

Thanks Hopper, I now have a better idea of what I'm trying to do.

John

[Anthony KnightsParticipant @anthonyknights16741]

Michael Cox tangential tool holder. MEW 179. I made both left and right handed versions.

[modeng2000Participant @modeng2000]

Michael, thanks for the photo. It is a much simpler version from what I first had in mind.

It is obviously the way to make it.

John

[Grizzly bearParticipant @grizzlybear]

Hi,

It's true what they say about a picture.

Bear………

[modeng2000Participant @modeng2000]

Hopper, I took on board your advice that a silver soldered joint would not be strong enough to withstand the forces involved in cuting especially intermittently. So I made a joint between two bits of 1cm square mild steel bar. Putting one end in the vice and a lever on the other end, I could feel the bar flexing but the joint remained sound. I couldn't apply enough force to break or bend the bar or joint.

So I'm going to continue with my approach in the knowlege that it will produce a strong tool holder.

John

[Tony Pratt 1Participant @tonypratt1]

Posted by modeng2000 on 02/06/2023 09:03:31:

Hopper, I took on board your advice that a silver soldered joint would not be strong enough to withstand the forces involved in cuting especially intermittently. So I made a joint between two bits of 1cm square mild steel bar. Putting one end in the vice and a lever on the other end, I could feel the bar flexing but the joint remained sound. I couldn't apply enough force to break or bend the bar or joint.

So I'm going to continue with my approach in the knowlege that it will produce a strong tool holder.

John

I on the other hand thought a silver soldered joint would be fine, glad to be proven right

Tony

[HopperParticipant @hopper]

Posted by modeng2000 on 02/06/2023 09:03:31:

Hopper, I took on board your advice that a silver soldered joint would not be strong enough to withstand the forces involved in cuting especially intermittently. So I made a joint between two bits of 1cm square mild steel bar. Putting one end in the vice and a lever on the other end, I could feel the bar flexing but the joint remained sound. I couldn't apply enough force to break or bend the bar or joint.

So I'm going to continue with my approach in the knowlege that it will produce a strong tool holder.

John

That's good. See how it endures over time under repeated shock loading. If not used all day every day it probably should do the job for hobby use.

I do tend to be a bit of an industrial-strength belt-and-braces kind of guy. I blame it on years of riding vibrating, bone-shaking, ground thumping old Harleys. As Mr Harley famously said to Mr Davidson "Nothing too strong ever broke".

 

Edited By Hopper on 02/06/2023 09:56:23

Edited By Hopper on 02/06/2023 09:58:19

[modeng2000Participant @modeng2000]

Hopper, I can understand where you are coming from. Belt and braces is often a good maxim but I think this time it is a bit too cautious.

[modeng2000Participant @modeng2000]

This is a rather rough tool holder made roughly as I have been describing.

It is not very pretty but it cuts mild steel like magic. I think because I wanted to prove my idea that I rushed making it not as refined as I would have liked. Machining the V grove was a difficult set-up because of the combination of three angles. The only way I could do this was to machine the grove before bending the holder, this removes one of the setup angles. Another point I would do differently next time is to have the bolt head on the other side of the holder.

Hope this inspires others to have a go.

John

[HopperParticipant @hopper]

Good stuff, well done. A lick of paint and it will look as good as a bought 'un .

[modeng2000Participant @modeng2000]

I think a polish up would make a lot of difference.

Quite a complicated machining procedure as I only have a mini-lathe with a milling crosslide vice these days. Still it was an interesting experience.

John

[Howard LewisParticipant @howardlewis46836]

It is amazing just what can be produced with limited resources but plenty of skill and imagination!

Howard

[modeng2000Participant @modeng2000]

Howard, having spent some time making this holder and realising some of its short comings I have concluded the Eccentric Engineering design is probably the optimum for such a tool holder.

The reason for silver soldering pieces together is because of my limited machinery. Achieving the compound angles used by the Eccentric holder is something I could not visualise with my equipment so the job was divided into managable sections.

i am quite surprised by the strength of a good silver soldered joint. I would have no concerns about using this method again.

John

[Author]

Posts