Cutting plastic tube

[Paul75Participant @paul75]

Hello Everyone

​I thought I'd use 10mm cut lengths of 20mm diameter plastic tube to make the 20 or so cylindrical Oerlikon nests for my 1/128th HMS Duke of York because I thought it'd be easier than shaping styrene sheet.

​However, much to my frustration, when I cut this tubing using a razor saw and mitre box, with the tubing clamped in place, I find that the cut is not perpendicular to the length of the cylinder and I get a wonky result.

​Given the care taken to achieve a straight cut, I'm at a loss as to why the cut is off kilter.

​Can anyone please advise me where I'm going wrong and/or a better method to obtain the result I'm after?

​Many thanks,

​Paul.

​

​

[Paul75Participant @paul75]

[mark69Participant @mark69]

Paul maybe the blade is bending, try cutting 1mm bigger with a hacksaw and sand down to the correct length ! ….mark

Edited By mark69 on 26/04/2016 22:37:15

[Colin BishopModerator @colinbishop34627]

Sawing is always a problem to get right. Much better to invest in a a mini tube cutter. These come in two sizes, one for very small tubes and one for larger ones.

You can see a selection here.

https://www.amazon.co.uk/Tubing-Cutters/b?ie=UTF8&node=1938882031

Once you have one you will wonder however you managed without it!

Colin

 

Edited By Colin Bishop, Website Editor on 26/04/2016 23:01:50

[David Marks 2Participant @davidmarks2]

As 10 mm is a standard thickness for plywood and 20 mm is a standard diameter for a wood drill bit i.e. the flat bit type. If you have a pedestal drill, then drill a 20mm hole in the ply, cut a length of tube over length, pace in the holes and file flush with the surface of the plywood.

[Francis MacnaughtonParticipant @francismacnaughton39461]

Otherwise, if you can get hold of some lithoplate from a printers this can easy to cut into rectangles and bent around a former to the required shape.

[Paul TParticipant @pault84577]

Hello Paul

The reason for the wonky cut is that your blade is bending as you are cutting, its not your fault as plastic tube is notourious for having this effect on thin blades.

Tube cutters are a good option but can crush some thin walled or rigid plastic tube.

The best hand tool is an engineers hacksaw with a 1in deep blade

This is the type of hacksaw with a standard blade

The deeper blade is shown here below the standard blade

Hope this helps

Paul

[CookieOldParticipant @cookieold]

Hi Paul , Welcome to the club, it,s not easy to cut dead true , i always part off on my lathe , or scribe a line around the tube and follow that with your saw while rotating the tube.

Dave

[Paul75Participant @paul75]

Hello Chaps

​Thanks for your replies and advice. I'll be buying a tube cutter and 1 inch hacksaw blade and see how I get on with these.

​All the best,

​Paul.

​

[Colin BishopModerator @colinbishop34627]

Tube cutters generally work OK with plastic tube if you take it gently with a series of light cuts. There is also the option of putting something inside the tube to support it while you make the cut, a length of dowel, rod or knitting needle for example.

Colin

[Tim CooperParticipant @timcooper90034]

I use the KS Metals tube cutter for plastic tube. It gives a smooth clean cut. As Colin says just take it slowly, tightening the blade against the tube a bit at a time.

Tim

[Paul75Participant @paul75]

Hello ​Everyone

​I've just bought a hand mitre saw with a 32 teeth per inch blade. I've found this reliably cuts plastic tube giving a straight cut perpendicular to the length of the tube. Lots of cut angles can be accommodated with the saw too.

​All the best,

​Paul.

​

​

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