Making bedding V Blocks

[wilson85]

Hello all,

Just a question regarding building aluminium V Block for a Barnard if anyone here has had a go at making them. How do you secure the recoil stud bushing? Make the bushing using threaded rod with a 9mm hole and tap the V Block and secure with loctite or just make a bushing with a light press fit with loctite to hold it in place?

Cheers

[Kakaduthunder]

Wilson, I have made several that were incorporated into chassis I built. One for a Barnard and one for are ingrown 700.

As I don't have cnc the easiest way to make the v is to step cut with a regular end mill then use a 45 degree chamfer cutter. I even noticed that Bunnings sells nice Sutton ones. You can do the hole thing with the chamfer cutter but it is very slow.

As far as the bushing I turned it out of 4140 slightly larger then the hole. I then seated it into the corresponding hole in the chassis with a vice and spacer. As the ally is a much softer metal you get a really good interference fit. If you are worried about it lock tight makes some retaining compounds for just this occasion. As the recoil forces act backward not up wards there really isn't risk of it moving if it is pressed in. I certainly didn't worry about it and it never moved.

Hope this helps.

[chrisw91]

I would make the bushing an interference fit. Either heat the block up or shrink the bushing into it.

[wilson85]

Thanks for the reply gents. Will go ahead with a press or shrink fit.

Kakaduthunder, I'll do what you recommend with roughing it out with an end mill. I have a 30 degree carbide router bit that Ill have a crack with. The Barnard V Blocks that I've looked at seem to be around 30 degrees.