3D printed hand wheels for driving 1605 ball screws

My DIY micro lathe project continues and one step I made recently was that I designed and made two hand wheels, which initially will be used for driving the X and Z shafts. These are 1605 ball screws, which in the end will be stepper driven, but that will be the last step of this crazy project, and until then I will need these hand wheels for my tests.

The idea was to make them large enough so that they can comfortably be rotated even at fairly high speed. I also wanted the handle to freely rotate, just like on professional hand wheels. This would make it easier to handle and turn at better precision. I did not add any scales, if I realize that I need it, I can always add that later. Instead of milling one, I decided to print one out of PLA. I know that real aluminium hand wheels would have been much better, but this is enough for my needs now, and I also find 3D printing fun, so I went for a printed solution, instead of a milled one. The designed is made in FreeCAD.

 The hand wheel consists of three 3D printed parts assembled together with M6 screws. I could have printed in two parts, but thought that this way it offers greater flexibility, and if I don't like the coupler I can always use a different one, made out of aluminium, or sone other material. Perhaps printing in two parts would have resulted in a nicer design, so maybe if I make new ones, I will change and try the two parts solution.

The wheel is 80 mm diameter, which I found just right in size. The wholes in the wheel are 5 mm holes for threading with M6 threads. On the other side of the wheel there is a circular pocket for an M6 nut which will hold the shaft coupler. 

 

The shaft coupler has a 10 mm diameter pocket on one side, and a 5mm hole on the other side. The 1605 ball screw shaft is 10 mm in diameter, so it fits well to that. The coupler is fixed to the shaft with two M3 x 5 mm grub screws through the two M3 nuts. The 5 mm centre hole is threaded for the M6 x 30 mm screw which is used for fixing it to the wheel. The nut will hold it firm enough, but if necessary, I can always glue the two pieces together as well.

The handle is 42 mm long and 16 mm wide at the widest part. Inside there is an 8.2 mm hole to fit a 31 mm long tube in it. This tube acts as a spacer to provide the right distance from the wheel and it allows free rotation of the handle. The screw is a 50 mm hex cap screw.

 

The screw can be tightened quite firmly, and because the tube is 1 mm longer than needed, the handle is a bit lose. This solution provides a very good free rotation of the handle

The screw is well hidden in the 10 mm pocket, giving it an extra good look.

Printing took about 7.5 hours in total for the three parts, but my printer uses only a 0.4 mm extruder. I printed with 0.25 mm layer height. The material is PLA, which I find is rigid enough for this sort and is also very good for tapping.

Just click on this link if you like this and wish to print the stl files:

https://drive.google.com/file/d/1pXTQiNqAh5BduZgYsOqA2MmtVy5DofAO/view?usp=sharing 

The files are provided free of charge, download and use the stl files if you wish.

If you find this useful and find that it saves you a lot of time and effort then I am very happy. I have however spend many hours and days on developing, testing and documenting every step of what I do, including this seemingly simple hand wheel. As a token of appreciation, your donation is of course welcome, but there are no obligations and the sky won't fall on you if you decide not to donate. If you however wish to contribute to my activities, then just click on the button below and that will allow you to make a donation if you do wish to do that.