Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
111 lead, so "pitch" is 18.5
John, if I'm interpreting this correctly then this is basically a twisted spline, with a full revolution of one spline "thread" being completed in 111mm.
OP, correct me if I misunderstand. And ditto if I'm not getting what John's described.
You are correct. I should have said lead instead of pitch. The distance of one revolution is 111mm
Sounds good. Is this a one-shot, or a run of parts? If one shot, either try the home-made single tooth broach, or if there's money available, you could find someone with a helix-capable sinker EDM, and after prepping a blank with the circular features needed, sink the spline into it.
The electrode could be a simple as a short slug of graphite projecting from an arbor, or as complicated as the full helix form.
no affiliation or experience with these, I remembered an old video where some Russian made a tool like this, chain driven, but it was probably for a larger diameter work piece, he used it to mill straight internal splines on a manual lathe, so I started searching and found these:
Live Lathe Tools | Sizes & Dimensions | How to Order | Eltool
and they even have a video:
They make helical broaches. The part stays still, they twist the broach itself as it pulls through. There's a helical guide for the broach. You better have a lot of money.Well, you could have a broach company make a "for real" broach for that, but I hate to think of the cost. You'd also want a special seat for the part with a good (shielded) thrust bearing on it to allow the part to spin freely while the broach passes through.
Five or ten I'd say yeah, big bubbles no troubles but I'd not be happy looking at 250. Not enough to go for bigtime tooling but too many to do it the cheap way.If you can fake it with a tool in the lathe you do the other features with that sounds like the best bet...
Maybe a giant tap ?
I could probably get one made here for 1/5 the cost of the US. Ja, it wouldn't last thirty years but it would do the job.You'd be around the cost of the broach, wouldn't you? I bet tap companies would turn pale, shut their doors, and place the "gone fishing" signs in their windows if you showed up with a print and RFQ...
Notice
This website or its third-party tools process personal data (e.g. browsing data or IP addresses) and use cookies or other identifiers, which are necessary for its functioning and required to achieve the purposes illustrated in the cookie policy. To learn more, please refer to the cookie policy. In case of sale of your personal information, you may opt out by sending us an email via our Contact Us page. To find out more about the categories of personal information collected and the purposes for which such information will be used, please refer to our privacy policy. You accept the use of cookies or other identifiers by closing or dismissing this notice, by scrolling this page, by clicking a link or button or by continuing to browse otherwise.