uxcell 6063 Aluminum Round Tube, 300mm Length 13mm OD 8mm Inner Dia Seamless Aluminum Straight Tubing 2 Pcs

I was surprised to find this item on Amazon, but the 12mm OD aluminum rod with 5mm ID bore was perfect for tapping with an M6 thread at each end and screwing in an M6 bolt at one end, then cutting off the head to leave a threaded post. Why? To make a perfect counterweight arm extension to the 12mm diameter arm of my Sky Watcher Star Adventurer Pro star tracker. In the long run, I found it was better to also add a bit more weight, but that too was easily fashioned from a galvanized steel pipe cap into which I screwed a bushing that held a fender washer tightly in place to trap about 300 BBs in the cap cavity. With a hole drilled into the cap end for a long M6 bolt to be run through it, the result was a functional 1-lb. fixed counterweight that I then screwed into a 150mm length extension. The counterweight arm already had an M6 screw in the end, to serve as a safety for keeping the counterweight from slipping off, so by simply removing that screw, the counterweight extension could be screwed on and the problem was solved.

I’m very happy with this product. I purchased the 12mm ID x 14mm OD to use as a liner to stiffen my FX Impact’s liner system. It fits between the barrel and inner shroud with just a bit of sanding. It fits nicely and is very stiff. It made my Impact much less hold sensitive! It’s always been very accurate but it’s much more consistent now. I used this between the barrel and inner shroud and the Arris carbon tube for the outer shroud. Looks great and works better. Stoti

12.15mm OD & 8.94mm ID. The tubes were not true either. I was able to make them work with some modification.

If you need precision then you might be out of luck here. In my case, i dont. One tube inner diameter is slightly under 8mm. But under would be okay as i can enlarge if needed. Inner and outer diameter is perfect for what i need.

As soon as I got the two tubes, 13mm OD x 7mm ID, I measured them with a micrometer. Both were dead on, as advertised, and exactly what I wanted. Perfect stock for why I needed them.

As impossible as aluminum spacers are to find, these tubes were a fantastic find.I used these to cut many spacers to make a collection for use with M8 hardware.

Reported as 13mm inner diameter, but actually 12. Not usable for my application. Not worth the cost of shipping to send back.

They have a consistent diameter from one end to the other, work for our shaft application.

Warning: the external and internal dimensions do not exactly correspond to the information. For example: 12 mm is actually 1/2 inch - i.e. 12.7 mm. Dimensions have therefore been approximated from inches to mm.