Milling a 45 degree 'v' slot

Holey poop! 12 videos @ 45mins each. That guy really needs to learn to edit!

Yeah, I really didn't want to tilt the head either but;

a) I've never done it before, so it'll be a learning experience

b) I'm not sure how trammed it was already anyway

This was last night's progress (obviously my work is underneath):

Go for it, Lee ...

‘though it’s interesting to ponder how much simpler it would be to cut the vees on a shaper.

MichaelG.

Nice one Lee, you will learn some much from 'having a go', rigidity in machining is one of the key elements & your set up is better than a tilting vise in that respect, as for re-tramming you will also learn from that experience & hopefully become a better machinist.

Tony

If it is not too late rig up some form of stop against one side of the work, left would seem best. That way you can turn the work 180 degrees to do the other side which I think would be better than tilting the head the otherway.

You can then repeat the cuts on the other side to the same settings (which you made a careful not of) and have a good chance of getting a similar cut either side. If the width ends up a bit large then take half off one side and flip again to keep the cuts symmetrical as you work your way down to the required measurements, scribed line is best used as a guide for parts that need to fit accurately like this..

If it woks on this one then do them all before hanging the head position to do the Tee slot but keep the vice and stop in position.

Fair comment. I'll just nip out and get one.

Thanks Tony. That's the plan (although I'm still relying on Morris the moose to make good).

I've already taken the work out of the vice Jason.

Plan is to flip the work. I have taken notes of the *relative* measurements.

+1

I the user has even less idea of how to use a shaper than they do about using a milling machine I wonder too.

Otherwise an ideal machine for the job in the right hands.

Edited By JasonB on 21/05/2020 10:06:12

Hi Lee, Guys,

Two things here, first it is almost impossible to accurately set the head at an angle of 45 degrees, which you will find out when you come to mate it up with the face that it is supposed to fit.

Second when you come to re-tram the head you will find that as soon as you tighten the securing bolts the head will move slightly. I've spent hours tramming the head on my mill and whilst it is now nearly spot on you will find that the tram moves as soon as you tighten the head locks. Not only that but the tram will change with the position of the head on the column.

I even went as far as making a tramming tool that gets me spot on ! Until I tighten something up.

Edited to add pictures

Here its just sat on a steel block.  Since this picture the dial gauges have been changed for a pair of 0.01 mm identical ones.

This picture shows it in use. The out of tram is quite obvious, nearly 5 thou.  Using this tool I can get 1/2 a thou sometimes.

Edited By John Baron on 21/05/2020 10:17:42

I have often wondered how you are supposed to acurately position a V on work with a head tipped over or even with the work tipped over. None of the usual edge finding techniques that I know of would work.

Actually its quite easy. Scribe lines to represent the centre line and "V" edges and work to those.

Show off.

Don't suppose you want to make me some, do you? 

Edited By Lee Jones 6 on 21/05/2020 10:51:14

That was a block of steel to make 5.

No probs in making some more, but the postage back to Blighty could sting a bit.....

That's my plan, although I'm limited to 4 at a time with my set-up.

It's okay, I was only jesting.

My plan is to make say 4 or 8 of my own and buy some from knock-offs when they come back in stock.

Yours look amazing by the way.  Are they T1s or T2s?

Edited By Lee Jones 6 on 21/05/2020 11:00:48

You do realise that the two vees are only there so that the holder can be used from both ends don't you? In reality a single vee at one end and a flat at the other will work as well as long as the vee is at the end the tool sticks out of. The two vees is actually bad tooling practice. The other issue with these tool holders is that in some of them the plunger does not pull in far enough to over centre and toggle, relying instead on friction alone to stop the holder coming loose in use.

Martin C

Lee

It may not be obvious but the Dickson toolpost & toolholder design is technically over-constrained with more locating surfaces than are strictly needed. There are engineering reasons but of a sort which folk line us don't need to worry about.

I would forget about accuracy on the outside Vee face and simply set things up so as to get the best possible finish on the wide, inner, Vee face cutting a little deeper so the outer Vee face is in the wind. Interestingly the wear, polish actually, marks on my factory Dickson / Rapid posts are on the outer Vee not the inner suggesting that maybe thats where location occurs. I really ought to blue things to find out what touches where, but life is short! However the inner Vee face is probably easier to cut and clearly equally functional. The narrower outer ones could be done with a smaller, cheaper, cutter tho'. Whatever works.

With several to do I'd not mess around with a vice or trying to tram the head at 45°. Use what you have and make a simple sturdy sine plate jig with a solid fence and clamps to hold the work in the right place. Forget angles, too fussy and we home shop types don't need to spend on the super accurate measuring equipment to get it really right.

Do it the old fashioned way by slope. An accuracy of one thou at one foot, or the metric equivalent, is well within ordinary capabilities and corresponds to about 1/20 th of a degree, 3 minutes of arc. No way will you tram a head to that sort of accuracy. If you have a decent DRO set up making an accurate sine plate is a piece of cake as is making a one time use block to get the angle.

We home shop types tend to fight a little shy of one time jig "disposable" tooling and tend to spend money on versatile equipment that can do lots of things which, mostly, never actually happen.

DRO sets really are a game changer here.

I'd expect to make up a sine plate style jig in less time than it takes to set up the head tram and vice. Takes a little longer but more useful to make the plate face a grid of tapped holes style, 1/4" or 6 mm in 5 spot dice in 1" or 25" square base pattern will hold anything we want to make. Stamp the riser block with the thickness / angle and pop it in box should you ever need it again. Probably will at 45°. Different angle. Make an new block just like that. I have nice gauge block sets and a fancy 3 way sine plate style stack but for all reasonable use a DRO will cut one to whatever size you need to set the sine plate when you need it.

Obviously set the fence so you can just flip the job to do the opposite Vee in the right place with the vertical head travel on the same DRO number or, better, hard stop.

The T shape slot in the back is hard to cut and harder to get in the right place. I'd cheat. Cut a plain slot then screw and glue the flanges on. Check that the slot depth is right before gluing. Having done number one lock the head setting for the finish cut on all the others. Theoretically its not as strong as factory carved from solid but I seriously doubt if anyone could prove weakness in practical use.

When you finish machine the tool slot it may well be easiest to dismount the tool post, lay it on its side on the mill table and use it as a jig to mount the holder for final machining. That way you know the slot floor is correctly aligned. I'd clamp the base of the new holder against a fence on the table which would work fine if you machine that face on the block first and use as the reference for all subsequent one.

Hafta say that if you are using carbide inserts there is much to be said for making some fixed holders with no adjustments for use with the insert holders only. With a good set-up and efficient machining habits 8 holders is as easy to make as 4.

Clive

Nice !

Blimey.

Thanks for taking the time to draft that Clive.

I'm going to need some time to digest all of it (do you have pictures? ).