An Old Way to Make a New Crank Handle

When the crank handle on [Eric Strebel]’s cheapo drill press broke in two, did he design and print a replacement? Nah. He kicked it old school and cast a new one in urethane resin.

In his newest video, [Eric] shows us his approach to molding and casting a handle that’s likely stronger than the original. The old crank handle attached to the shaft with a brass collar and a grub screw, so he planned around their reuse. After gluing the two pieces together and smoothing the joint with body filler, he packs the back of the handle with clay. This is a great idea. The original handle just has hollow ribbing, which is probably why it broke in the first place. It also simplifies the cast a great deal.

Here’s where things get really interesting. [Eric] planned to make a one-piece mold instead of two halves. At this point it becomes injection molding, so before he gets out the reusable molding box, he adds an injection sprue as an entry point for the resin, and a plug to support the sprue and the handle. Finally, [Eric] mixes up some nice bright Chevy orange resin and casts the new handle. A few hours later, he was back to drilling.

Crank past the break to watch [Eric]’s process, because it’s pretty fun to watch the resin rise in the clear silicone mold. If you want to take a deeper dive into injection molding, we can fill that need.


24 thoughts on “An Old Way to Make a New Crank Handle

  1. Very informative and awesome article. At first, I thought it was going to be a 3D printed handle which I did not think could handle the stresses involved, but the casting approach is a great option and, as it appears, a successful one. Thanks.

    1. Yes… I’m getting “3D Printer Fatigue” these days from all the HaD posts. But at least it’s better than the days when every other post here was about some sort of “HaD Contest”.

      1. Well, the only reason I did not think that a 3D printed handle would work in this situation is because I 3D print stuff all of the time. I actually enjoy the 3D stuff HAD puts out. It has helped me modify my printer and it is working very well now. No site can please all of the members all of the time, that is impossible. I think they do a pretty good job of mixing it up. It is not like anyone forces us to read any particular article right? Of course, if you are not into 3D printing, I can see where you might realize some fatigue. My advice is to jump in and try to keep up as this technology is still in its infancy…in my humble opinion.

      2. Me also. It’s nice to see a fix done which doesn’t require a 3D printer.
        It’s almost these days a case of “when the only tool you have is a hammer” and perhaps some people that own 3D printers need to grow their skills rather than relying on the one tool?

        This is a nice fix I don’t think it’s a hack.
        A hack would have been to get some steel and weld up something strong and functional in about 5 mins.
        This is an elegantly designed and executed repair. Not a hack.

    2. I 3d printed (an admittedly reinforced) replacement for mine when it broke, and it’s worked fine for years.

      I certainly don’t think it warrants an article on hackaday though.

    1. You youngsters get off my lawn! I accept nothing newer than chipped flint and wooden sticks strung together with deer gut as “old school.” Now excuse me while I 3d-print an atlatl and a spear.

  2. Interesting to watch the video though. Mine is a less than accurate pull down lever version. Although I’ve been tempted to convert it to car window winder driven and add an encoder so it follows a variable resistor.

  3. When the crank broke on my mid-90’s vintage Jet DP, it failed where the knob threads into the handle. It might not have failed if it had a bushing. This version appears unreinforced in that area?

    I replaced the plastic crank with a piece of aluminum, and replaced the drill press with a nice old Powermatic 1200.

      1. One issue that can happen with with repairing is the issue of causing stress in other areas as they can no longer compress and elongate in a smooth gradient.

  4. Many of the solutions suggested in these comments does not consider the factor that they would not make very interesting videos for his channel even if they are cheaper and/or more effortless.

    1. I can see the video playing now… handle breaks / guy jumps on google to find part number / screenshot of order / classic pages falling from calendar as weeks pass / box arrives / “iPhone” unboxing procedure as often seen on youtube / part won’t fit / guy thows entire drill press in bin and video concludes with a fading shot of him ordering a new one…

  5. That’s real interesting to watch. I could see doing that just for fun.

    However, if you had to hire somebody to make a part like that, it would cost as much as a new drill press.

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