Root nut installation using a small air chisel

I've got a heap of M5 root nuts (

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) to install in some enclosures. The plan was to peen them by hand using a hammer & punch tool into an 8mm hole in 1mm thick sheet steel cabinets.

I was wondering if a small air chisel fitted with an appropriate punch tool would do the job (without all the hammer pounding)....

Air chisel link:

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Any thoughts or similar experiences? Thanks.

Reply to
Den
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When I can't use an arbor press I install them in aluminum by starting them straight with a screw, then tap them seated with a hammer and flat block of steel. Sometimes a large C clamp will work.

Jim Wilkins

Reply to
Jim Wilkins

When I can't use an arbor press I install them in aluminum by starting them straight with a screw, then tap them seated with a hammer and flat block of steel. Sometimes a large C clamp will work.

Jim Wilkins

Thanks for the Jim, putting them into aluminium is much nicer, unfortunately I've got a few hundred to install.

Reply to
Den

On Fri, 28 Mar 2008 19:44:36 +0900, with neither quill nor qualm, "Den" quickly quoth:

AU living is pricy, isn't it? A very similar gun with 5 chisels goes on sale in the States for $4.99 on a regular basis. It's normally $9.99. AAMOF, it's on sale right now. Got any US buddies?

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My experience is mostly with reseating pemnuts.

I'm guessing that those nuts are chrome-plated brass. If so, build a proper setting die and weld or screw it to a cheap air chisel shank. It should do just fine. Be sure to back up the nut with the other half of the die (or a lot of mass) while setting.

If you're going to be sealing that, maybe a hydraulic press would work better. It would give you an adjustable seating pressure for a gasket to work better.

G'luck!

-- Books are the compasses and telescopes and sextants and charts which other men have prepared to help us navigate the dangerous seas of human life. --Jesse Lee Bennett

Reply to
Larry Jaques

I think so, if it's small enough to be controllable. One of these might work better than the larger general-purpose air hammers:

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Reply to
Don Foreman

Thanks Jim, Larry & Don. I just picked up a small air hammer + 4 chisels, AU$22 which I thought was quite a good price - probably about US$19. I faced the end of the round punch chisel and put a .040" step on the end. The chisel was hardened but just machinable. With the air pressure at about 50 PSI it peens the root nuts very nicely, a smooth finish, tight and best of all quick - all without having to swing a hammer!

Without the feedback from you guys I'd be doing this the hard way.

Reply to
Den

On Sat, 29 Mar 2008 10:58:50 +0900, with neither quill nor qualm, "Den" quickly quoth:

Good deal. So show us a link to _pictures_, eh, Den?

-- Books are the compasses and telescopes and sextants and charts which other men have prepared to help us navigate the dangerous seas of human life. --Jesse Lee Bennett

Reply to
Larry Jaques

Now in the drop box. I modified the punch further so it has a "pilot" to centralise the punch over the nut, it seems to work better. The marking around the hole on the sheet surface is from swarf during drilling.

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Cheers

Reply to
Den

First, ask your local supplier and find out whether they have ready- made tooling available for the nuts - that will determine the air tool you have to buy to drive it.

And if your local supplier doesn't know, get hold of whoever makes those root nuts (they could be going through several hands before they get to you) and ask them.

Get the tooling wrong, and you damage the threads on all the nuts. And you'll pay a LOT less for mass production tooling, rather than going to a local shop and having them design you a one-off. And when the one-off wears out or breaks you have to pay again.

Yes, that would work - IF the tooling shank size and style fits. And unless your local samoleans are trading severely below the US Dollar they certainly aren't giving anything away.

Note that they have several different power levels, and tool shank designs, and many with your choice of pistol or straight grip.

-->--

Reply to
Bruce L. Bergman

Well done!

Reply to
Don Foreman

On Sat, 29 Mar 2008 14:25:32 +0900, with neither quill nor qualm, "Den" quickly quoth:

Cool. One suggestion. You might want to cut that guide diameter down and sheath it in copper, delrin, or teflon so it doesn't gore the threads as it seats the nut. Alternatively, create a male die piece which threads into the nut and drill the center of the chisel shank to accept it. It'd keep the threads safe by filling them.

-- Books are the compasses and telescopes and sextants and charts which other men have prepared to help us navigate the dangerous seas of human life. --Jesse Lee Bennett

Reply to
Larry Jaques

Good suggestion, I'd thought (and worried a bit) about that, the punch is too hard to drill into so I can't put a pin back the other way and the diameter at 5mm is maybe a bit small to sheath the pin in Cu/plastic. I figure another two options are:

1) make the pin on the end of the punch longer so it goes completely past the threads and into a hole in the die.

or

2) get rid of the guide pin altogether and go back to the original small step on the front fo the punch.

I'm not starting the installation until Tuesday so I've got another day or so to try alternatives. Thanks.

Reply to
Den

On Sun, 30 Mar 2008 09:22:58 +0800, with neither quill nor qualm, "Den" quickly quoth:

Heat it to remove the hardening, drill it out, tap it, and add a Cu/plastic button with a screw to hold it in, then heat and quench for a harder tip?

OK, now you have three options. G'luck.

-- Books are the compasses and telescopes and sextants and charts which other men have prepared to help us navigate the dangerous seas of human life. --Jesse Lee Bennett

Reply to
Larry Jaques

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