gripping the inside of a small hole

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jor2daje

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Hey guys I've got a bit of a improvement Id like to make at work but Im not sure about the best way to do it. We have the female halves of banana jacks that we need to instal in a panel the only problem is they are so close together you cannot fit wrenches around the nut and the flats on the banana jack so for now we have just be doing it as tight as you can by hand. I want to make something that grips the jack from the front basically where it would plug in, its about .1625" in diameter and .625" deep. Ive tried two things so far, first was to make a tapered tool that was covered in rubber, this was simple and worked fairly well but the rubber wore out every 10 or so jacks and we instal hundreds a day. The other more successful tool was a piece of stainless with a reverse taper ( ? bigger at the end) that was slotted and tapped 6-32, it would squeeze together to fit inside but when the screw is inserted it expands and grips. This works fairly well but is quite time consuming and actually slows down our production haha, also it provides much more grip than is necessary because they are just plastic. If you guys have any ideas Id love to hear them, its really great to see other peoples approaches to a problem. If my explanation of my current tools was unclear let me know and Ill draw a picture

1498-107.jpg
 
How about getting a pair of those snap-ring pliers that have jaws that open when the handles are squeezed. Grind the points down to the point where they will fit into the banana jack,

It wouldn't provide a wonderful grip but it might be good enough for your purposes.
 
Perhaps a small socket from the back. Grind opposite sides to just leave two opposing flats extended. Fingers could spin the nuts down and then - since the assembly is low torque - the modified socket could take it down snug.

Alan
 
no chance of a panel re-design to proper/standard clearance betwen jacks and use a d-hole as well ?
 
I'd suggest a pair of long nosed pliers with jaws of sufficient length, even a pair of regular gas valve pliers that have had the jaws ground down. Make a ring out or copper or steel that will just fit over the outside diameter of the jack, maybe just a bit larger. Solder this ring onto the nside of both jaws of whatever style of pliers you decide upon such that the pliers are at a 90* angle to the ring. once everything has cooled down, cut the ring in half and you will have made yourself a tool that you can grip the jack on the outside surface. For tightening the nut, a nut driver or a modified deep well socket could be used. Both of these methods will ensure that you get sufficient torque to the fitting without damaging it. I realize that your request was for gripping the inside of the jack but I thought I would throw this idea out for entertainment. 8)


BC1
Jim
 
Perhaps a 5/32 Cleco Fastener could be adapted. They are commonly used to hold sheet metal parts together while riveting and drilling more holes for riveting. Don't know f they would supply sufficient torque. The basic fastener is about half a dollar each and installation tools gore from about 9 dollars up.

http://www.challengers101.com/ClecoTool.html
Gail in NM
 
Pretty close to Gail's reply. If they are 4mm sockets, I worked for a company here in UK that made panels etc. with many of them.

Not screwed and nutted but they had plain bodies and were fixed by Starlok washers.

similar to these :

http://www.toolfastdirect.co.uk/acatalog/Uncapped_Starlok_Washers.html

One quick swipe with a hand press and you were done. About 5 secs. each.

I have looked but cannot find them anymore :( but IIRC they were made in Denmark.

I am not familiar with any US sources, but maybe worth a look around.


Only downside, they were a hideous job to remove ... DAMHIK

Dave BC
 
Building on the suggestion above, you might want to look at "speed nuts" which a formed sheet metal fasteners that you can press onto a threaded fastener and the prongs engage the threads . The socket can be unscrewed if need be, but there's no turning required to install the part. Just press it on. They're use a lot on cars and appliances. Easy to assemble and they can be taken apart. What is the center distance between the sockets and what is the diameter of the threaded shank?
 
For the front, I would make me a tool like this:

Spannzange_Teileansicht.JPG

(Source: http://www.gregory.de/images/Produkte/CDS/Spannzange_Teileansicht.JPG )

Possibly with a knurled body and I would use a knurled nut / screw or a star handle for closing the collet.

You could even make a collet with 4 arms (first at 45°, second at 135° third at 225° and fourth at 315° )

And for the nut, you could use a modified (reduced diameter) socket wrench or a tube wrench.


Regards Florian
 
thanks for all the great ideas guys, Ill try again at the eccentric shaft idea, I tried earlier but I didnt knurl it or anything. I like the collet ideas for grip but its a little time consuming, the reverse pliers and cleco tools both seem very viable. Thanks again
 
Make a miniature strap wrench from a screwdriver handle. Cut the end off a phillips. Put a slot in it and a flat on one side, then a piece of rubber strap in the slot ( at a 90* angle to the shaft), and pinch closed. Lay the end of the rubber around the jack and under the flat on the screwdriver, twist the handle.
 
Cll the supplier of the part and tell them you want clutch head( maybe not exact word) it is a round nut with 2 notches on the face rather than the sides, tightened with a socket that matches. GM used plenty on dashboards in the 70's
 
jor2daje,
buy the jacks with a flat on the threaded side, punch a " D "hole and be done with it. For the nut use a nut driver as shown.

Hilmar
 
Anthother thought. you could make somthing like a small hole gage except a knurled end to grip instead of a ball or half ball that hs minimal contact.
2ZVC5_AS01.JPG
you might ever try a inexpensive full ball one or even modify it to increase surface area. I personalty would not want to try to use one of my Starretts as a gripper.
Tin
 
I think a quick way to do up a lot of these things would be a cone shaped friction driver. The cone is made of rubber, and can be attached to what ever you need for driving it. I don't have a picture of one, but they look a lot like a small rubber test tube stopper. We used these to screw in nylon smooth headed screws. You can use it by hand with a screwdriver type handle, or use cordless screwdrivers to drive them, as we did.

Dean
 
Since this is a production operation, you might consider a pneumatically operated drawbar and "O" ring - the cylinder hydraulics the "O" ring to secure.

"O" ring life is limited but they're cheap and easy to replace.

A square section polyurethane ring works better but you generally have to make them.

Ken

Dump.jpg
 

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