Cutting and Filing Tiny Lengths of Rod and Tube

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Lindsay G
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Cutting and Filing Tiny Lengths of Rod and Tube

Postby Lindsay G » Thu May 07, 2020 4:07 pm

Perhaps a few have uncovered this long ago. For years I’ve had problems cutting short lengths of tube and rod for detailing where the tiny items would fly off in all directions or disappear into the shag pile (remember that?!). Recently I have been soldering whatever is to be cut to some PCB then cutting or grinding (particularly for hard syringe needles) the pieces off but heat from the latter could melt the solder and off they’d fly. Evidence of the soldering techique can be seen on the PCB below.

Whilst sitting down to cut some nuts for a loco currently under construction, a tiny light went on in my brain (or was it a light in my tiny brain), when I spied a groove cut in the PCB, and lodged the rod (hexagonal rod on this occasion) in it and set about it with a piercing saw. It cut without problems and the small piece remained lodged in the groove. Hopefully, fewer missiles flying about from now on. Tubing has been cut in the same way since. Just wish I’d thought about this years ago.

cutting tip.jpg
cutting tip.jpg (78.66 KiB) Viewed 1371 times

There is a nut in the right image between the 20p and the rod complete with hole in the middle for ease of positioning and soldering. Must try tapping one, yeh right!

Getting the length correct or cutting square is rarely going to happen (with me at least), so I cut oversize then ram a cocktail stick in the hole and rub down on a piece of wet and dry.

Lindsay

Enigma
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Enigma » Thu May 07, 2020 5:53 pm

I cut using a pin vice with just over the amount I want sticking out of the jaws. I hold the pin vice in the big vice and rotate it slowly as I cut. If its tube I place a small drill 'up the hole' and this stops the part flying off and the saw blade just rotates the drill. Rod is a bit more tricky and your idea may be a solution, thanks.

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Will L
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Will L » Thu May 07, 2020 11:42 pm

The quick, easy, and with a bit of practice, remarkably accurate way to cut thin walled tube is role under a sharp knife blade you're pressing down on.. If its the sharp end of a thin strait edge blade under your finger, you can stop the cut off section from leaving because it is also under your finger. Failing that put a bit of wire down the tube. This should not be too close a fit to the inside of the tub or you will have difficulty getting the cut piece off the wire.

While I have found a number of reasons for cutting short lengths of tub, I never cut off shot lengths of wire unless and until I've already attached it to something else. So its cut with snips and file the end flat.

Lindsay G
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Lindsay G » Fri May 08, 2020 12:09 am

Hi Will,

I've recently purchased some Albion Alloys tube that, as you say, is amongst thin wall tube that is easy to cut in a number of ways especially with a new blade, but some other tube - especially steel hypodermic needle tube - can't be cut that way. CK tube is quite thick in diameter as well.

I'm with you in not cutting rod/wire until it is attached to something - if the diminutive item does go astray it has a long length of wire attached to it making discovery rather easy. But with the production of such things as nuts, the option of keeping them attached to the rest of the rod is gone.

Lindsay

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Will L
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Will L » Fri May 08, 2020 12:21 am

I should have guessed this was all related to loco plumbing, (like the safety valve by the way) it was doing that which got me producing slivers of brass tube. I agree it probably wont work on steel hypodermic tube, but given the fine rage of brass tube available for this sort of job, why use anything else?

And isn't it time the wise were in bed?

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David B
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby David B » Fri May 08, 2020 9:50 am

There are tube cutting jigs/vices such as the one below from the Tools 'n' Tools site. They are not cheap (this one is £25) but if one is likely to be cutting tube (or rod) of a certain length, repeatedly, then it could be a useful investment.

tube cutting vice.jpg
tube cutting vice.jpg (45.35 KiB) Viewed 1160 times

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Le Corbusier
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Le Corbusier » Fri May 08, 2020 10:02 am

Will L wrote:The quick, easy, and with a bit of practice, remarkably accurate way to cut thin walled tube is role under a sharp knife blade you're pressing down on.. If its the sharp end of a thin strait edge blade under your finger, you can stop the cut off section from leaving because it is also under your finger. Failing that put a bit of wire down the tube. This should not be too close a fit to the inside of the tub or you will have difficulty getting the cut piece off the wire.

While I have found a number of reasons for cutting short lengths of tub, I never cut off shot lengths of wire unless and until I've already attached it to something else. So its cut with snips and file the end flat.


Putting the wire in the tube is for me vital .... otherwise there is a tendency to deform the tube which is a real pain if you then want to run said wire through it. To date I have used the coping saw with the tube held in a vice and a suspended tray beneath to catch the offcut ... must try the knife ruse to see if I can make it work.

Finding a method of jigging it to guarentee length for my point rodding chairs would be a big win.
Tim Lee

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Rod Cameron
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Rod Cameron » Fri May 08, 2020 1:18 pm

David B wrote:There are tube cutting jigs/vices such as the one below from the Tools 'n' Tools site. They are not cheap (this one is £25) but if one is likely to be cutting tube (or rod) of a certain length, repeatedly, then it could be a useful investment.


David, have you found a minimum length you can cut? Probably very small given the description of cutting eyelets and jewel settings.
Rod

David Knight
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby David Knight » Fri May 08, 2020 1:50 pm

Rod Cameron wrote:
David B wrote:There are tube cutting jigs/vices such as the one below from the Tools 'n' Tools site. They are not cheap (this one is £25) but if one is likely to be cutting tube (or rod) of a certain length, repeatedly, then it could be a useful investment.


David, have you found a minimum length you can cut? Probably very small given the description of cutting eyelets and jewel settings.


A different David here Rod but looking at the scale on the tool and assuming it is in mm I would say that 1mm would be the minimum size with the stop moved right up to the face of the tool. The guide slot appears to be 1mm in from that point.

Cheers,

David

Porcy Mane
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Porcy Mane » Fri May 08, 2020 4:06 pm

Hello,

I'm with enigma for cutting micro bore. I tend to hold the work piece in a cheap Chinese pin vice (I wore my decent 1950's Elipse pin vice out way back in the mists of time), setting the length of cut using the depth gauge of a cheapo digital calliper after adding the width of the cutting blade.

For cutting I use high quality 89 TPI blades in a piercing saw but I just hold the pin vice in my fingers, rotating as I cut. To stop the finished items going into orbit I put a bit of grease on an old drill bit or piece of wire of appropriate size which is slid into the bore of the tube.

I find I can constantly cut micro bore to the same size. The photograph shows four 09mm o/d x 1 mm sections of tube and a piece of 0.4 mm o/d tube with the end countersunk.

CuttingMicroBore© PwD2020-EditSm.jpg


P

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David B
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby David B » Fri May 08, 2020 4:23 pm

Rod Cameron wrote:
David B wrote:There are tube cutting jigs/vices . . .

David, have you found a minimum length you can cut? Probably very small given the description of cutting eyelets and jewel settings.


I imagine the minimum to be the distance between the groove for the saw and the end with the stop up tight which looks like about 1.5mm.

Proton
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Proton » Fri May 08, 2020 6:32 pm

David B wrote:There are tube cutting jigs/vices such as the one below from the Tools 'n' Tools site. They are not cheap (this one is £25) but if one is likely to be cutting tube (or rod) of a certain length, repeatedly, then it could be a useful investment.

tube cutting vice.jpg

Studying the picture closely, I can't work out the actual cutting action. Can anyone see how the cut actually takes place?

PBM.

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David B
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby David B » Fri May 08, 2020 6:46 pm

The slot on the right of the clamp is where you use your fret saw.

Winander
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Winander » Fri May 08, 2020 6:51 pm

Proton wrote:Studying the picture closely, I can't work out the actual cutting action. Can anyone see how the cut actually takes place?

PBM.


At first I thought it was a guillotine, but the lever with the knurled knob is to hold the work. A piercing saw in the slot to the right of it does the cutting.
Richard Hodgson

Proton
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby Proton » Sat May 09, 2020 2:13 pm

David B wrote:The slot on the right of the clamp is where you use your fret saw.


Thank you.

dclift
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Re: Cutting and Filing Tiny Lengths of Rod and Tube

Postby dclift » Tue May 19, 2020 5:22 am

I am afraid that I am falling behind in reading the Forum, there being so many interesting posts during Lockdown. Anyway, this might (or might not) be of interest.

I have a slightly less upmarket version of the device for holding tube for cutting. I cannot recall where it came from. The saw blade does indeed run in the slot to the right of the blade, but it is not necessary to push the end of the tube or rod to be cut right up to the stop, hence it is possible to cut off as little as you want. It is possible to insert a packing piece between the end of the tube and the stop if you need to cut off several tiney pieces of the same length, but this is a bit of a fiddle.
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David Clift.


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