When I get bored of waiting for someone else to do something I sometimes end up having a go at doing it myself. The hobbed insert in my previous post is no exception
Below is my setup using a drill stand. The 12mm round brass bar is held using a U-Shaped wooden clamp that mounts some 6901ZZ bearings, with an ID of 12mm and an OD of 24mm. I created some dimples on the 12mm brass bar with a punch to create an interference fit in the bearings. This stops things sliding around whilst doing the hobbing. One advantage of the drill stand (which is normally a disadvantage) is that it can swivel around the support pillar. So I was able to push the M3.5 tap closer and closer to the brass bar by pulling the handle to clockwise.
The next problem is how to drill a hole perfectly central down the middle for an m4 tap, again without a lathe. In the meantime the Conrad M4 Inserts have arrived in the worlds most ridiculously over sized box:
Why order from Conrad? I tried ordering from them, got a similar box with a catalog, a hole in the corner and no parts 🙂 I did get refunded, but decided to order from mendel-parts.com since they have cheaper shipping. Unless you got even cheaper shipping due to living closer to their warehouse?
I didn’t check but I assumed it would be cheaper to order from Conrad UK since I am I’m the UK rather than from Netherlands
In case you haven’t seen it yet, this is how you drill down the middle using a drill press. I’ve used it for my mendel extruders without a problem:
http://vik-olliver.blogspot.com/2010/02/drilling-down-middle.html
Someone just tweeted me the exact same link. Oh no! I suppose I am using twitter now. I hate it, we should be using something free (as in freedom) like identi.ca