Cutting a slot in aluminium tube with a jigsaw

I posted yesterday about a plan to use a small router to cut a slot in aluminium tube:

http://bkhome.org/news/201909/figuring-out-how-to-cut-with-a-router.html

I would like to thank scsijon, Derek and sage, who responded with advice on using the router to cut aluminium. Scsijon advised to make sure the work piece is very securely clamped down, to avoid a disaster, and he and Derek advised to use a good quality router bit -- Derek advise to use the dual-flute design as the single-flute tends to pull to the side.

The router is somewhere on the highways crossing over from the other side of Australia, so I decided why not have a go using a jigsaw.

The problem with a jigsaw is the vertical movement of the blade. I chose 16mm outside-diameter pipe, with 1mm wall thickness. I realised that the vertical movement of the blade is likely to be such that it will come completely out of the slot that is being cut. Which was found to be the case.

Anyway, decided to give it a go. Recycled tube out of prototype #1, so not throwing away money if I wreck the tube. Firstly, I cut a hole as a starting point. This was done by drilling a hole, then using small round and flat files:

Then packed it so that the blade would just reach the bottom of the inside of the tube, but not actually hit it:

However, the blade was still coming out of the tube, about 3mm. When the blade comes out and plunges back down again, it is liable to catch on the side of the cut, however, I found that by cutting extremely slowly, it did actually cut:

However, where it became too difficult is doing the other side. A 10mm slot is required in the tube, and cutting the other side, when the blade plunged down, it would push the middle piece of aluminium down, completely jamming things up -- it is a wonder that the blade did not break.

I think that this technique is feasible if a larger diameter tube is used. Well, the proposed prototype #3 will accommodate a larger tube. This tube is to be the runoff for the waste water, and I already have some plastic pipe that will slide onto the 16mm tube, for runoff into a container. But, should be able to acquire larger-diameter plastic pipe.

Stay tuned, will try 25mm (1 inch) aluminium pipe... 

EDIT:
The 16mm tube has been successfully cut, using a rotary saw. See next blog post:

http://bkhome.org/news/201909/cutting-the-solar-distiller-runoff-tube.html 

Tags: nomad