Cutting fine metal tubing question

Thanks for all the ideas, tips, suggestions, etc.

If you do get any distortion of the material, you can use a sewing needle or a straight pin to re-shape the opening and round it back out.  I've done this when I've gotten some squashed tubing.

You might need to file or sand the edges and remove any burrs created when cutting or snapping the tube, anyway.

goldhammer

Might try an old, repeat, old razor saw blade. Might leave a little more cleanup than the knife blade.  I usually go the knife route with brass and alum.

I save my old blade, since I find myself using the tip 1/3 for plastic, and do the cutting of tude with the heavy back end of the blade.  Makes use of something that would normally get tossed.

 

I also keep old blade  on hand for various uses.  But for things that dull blades quickly, I keep one handle with one that has the 45 degree cutting edge.  I find that shorter edge seems to hold its edge longer.  May be something about how the force gets applied.

goldhammer

Might try an old, repeat, old razor saw blade. Might leave a little more cleanup than the knife blade.  I usually go the knife route with brass and alum.

I save my old blade, since I find myself using the tip 1/3 for plastic, and do the cutting of tude with the heavy back end of the blade.  Makes use of something that would normally get tossed.

 

goldhammer

Might try an old, repeat, old razor saw blade. Might leave a little more cleanup than the knife blade.  I usually go the knife route with brass and alum.

I save my old blade, since I find myself using the tip 1/3 for plastic, and do the cutting of tude with the heavy back end of the blade.  Makes use of something that would normally get tossed.

 

Good ideas GH! Thanks! You are quite correct about the areas of the blade used.

Might try an old, repeat, old razor saw blade. Might leave a little more cleanup than the knife blade.  I usually go the knife route with brass and alum.

I save my old blade, since I find myself using the tip 1/3 for plastic, and do the cutting of tude with the heavy back end of the blade.  Makes use of something that would normally get tossed.

Well it sure sounds like there are multiple methods to choose from. I will likely try all mentioned just to see what works best for me. My fine tubing is all brass, so it sounds like for the blade technique I will need a good stock of those on hand. 

Many thanks to all for schooling me on how to try something new.

I have used a tube cutter and a hobby knife for cutting aluminum tubes. Following are photos showing the results. The tube in the photos is 1/4" in diameter. I am not sure that the tube cutter would work on a very small diameter tube.

This is the way the end of the 1/4" tube looks when it is removed from the package. Nice smooth cut with no burr.

This is the tube cutter. The round cutting blade is tapered.

This is the end of the tube after it was cut with the tube cutter. The tapered blade  creates a burr on the end of the tube. The burr can be removed by placing either a hobby knife or file into the end of the tube and then rotating the tube. The end of the tube then needs to be sanded smooth.

This is the end of the tube after it was cut by placing a hobby knife against the tube and rotating the tube as Nathan recommends. Note that there is no burr. A light sanding may be necessary.

GMorrison

The problem with all tube cutters is that they crimp in the end of the tube ever so slightly. Thats ok if you come back and grind the end square, or cut them with a rod inside the tube and then remove the rod and snap it. I just find the Dremel with the abrasive disk perfect at high rpms for the job.

 

The tubing cutters will work well on hardened tubing, not on soft stuff. It will not work well on aluminum tubes.  K&S brass comes in two forms, hard and soft.  Most is the hard stuff, the soft is only available in a few sizes, so most brass tubes will be okay for those cutters.

One thing about the knife scoring techniques.  When cutting brass, the blades go dull pretty quickly if you are cutting very many times.  Be ready to change blades if you are doing a lot of cutting.

I have used all three methods of cutting- all work. If cutting soft aluminum tubes, though, it will deform with the knife scoring or the tube cutter.  For aluminum I use the Dremel and abrasive disk.

I have used a saw in the past, does ok but it leaves it needing some clean up. I plan on getting one of those K&S tube cutters, says it will do down to 1.5mm. For £9 its got to be worth a try.

But i have not found one that will go smaller than that.

I'm crude and cut with a pair of diagonal cutters.  Then pinch with needlenose back to about round then sand off the defect part.  Pretty quick actually.

stikpusher

 

 

GMorrison

 

 

stikpusher

Thanks Nathan. I never would have thought of that... I was thinking of using my Dremel with a cutting wheel... and dreading that approach.

 

 

 

 

I don't know why? That is the way to go. I use those abrasive disks, they come in a bottle of several dozen. They are so fragile that I use two at a time.

 

 

 

 

 

 

Well, parts of the cutting discs tend to fly, or the part I’m trying to cut off flies away into the twilight zone... that’s all...

 

I use these fine circular saw blades from Pfingst shown in the video ... You want to use them at high speed and they will go through the tubing like butter ... and very clean ...

Paul

Hi!

Tucing cutters do not go that small. The hooby knife is the right way to go.

GMorrison

 

 

stikpusher

Thanks Nathan. I never would have thought of that... I was thinking of using my Dremel with a cutting wheel... and dreading that approach.

 

 

 

 

I don't know why? That is the way to go. I use those abrasive disks, they come in a bottle of several dozen. They are so fragile that I use two at a time.

 

 

 

Well, parts of the cutting discs tend to fly, or the part I’m trying to cut off flies away into the twilight zone... that’s all...

The problem with all tube cutters is that they crimp in the end of the tube ever so slightly. Thats ok if you come back and grind the end square, or cut them with a rod inside the tube and then remove the rod and snap it. I just find the Dremel with the abrasive disk perfect at high rpms for the job.

e-bay has hobby tube cutters for $2-$3 , delivered .

stikpusher

Thanks Nathan. I never would have thought of that... I was thinking of using my Dremel with a cutting wheel... and dreading that approach.

 

For the diameter of tubing you're asking about Nathan's method is the best. I just place the tubing on a scrap piece of glass and roll it under the back part of the blade with gentle pressure and it breaks off very clean.

Mike 

stikpusher

Yes, one of the companies that makes tubing, K&S or something like that, makes tubing cutters and benders. Will those items work on such small diameter tubes?

 

As already mentioned, use a new sharp hobby knide blade and roll it back and forth. A pipe cutter will most likely crush the thin walled pipe and not cut it. Give it a go...

Yes, one of the companies that makes tubing, K&S or something like that, makes tubing cutters and benders. Will those items work on such small diameter tubes?

If you have an Automotive/ part's store near you, get a tubing cutter.

It's used for cutting steel , copper, or aluminium fuel line's , transmission line's , and on really "old school" car's copper brake line's

They sometimes come in tube bending kit's, but dont buy the whole set if you only need the cutter. ( Or DO buy the whole set... comes in handy for all kind's of project's. )

Thanks Nathan. I never would have thought of that... I was thinking of using my Dremel with a cutting wheel... and dreading that approach.

Use your hobby knife and apply light pressure in a rolling motion back and forth. All you‘re trying to do is score the tube around it’s circumference. Then just snap the end off. It should break clean. Kind of hard to explain. I think Albion Alloys has a video on it. Maybe You Tube?