Dave,
Make a bunch of small accurate collars (say 1/4" thk with a set screw) place on the each end mill to restrict how far the end mill
enters the R8 collet. When the collet gets snug move the end mill into it as far as the collar allows and complete tightening the R8.
Match mark placement orientation.
The collars provide for quite accurate repeatable length as defined in a tool table. Try it out and may be satisfactory.
Poor mans quick change holder for the mill!

RICH

Hi Dave
Different machine, different needs. Always interesting to see how others do it. I keep learning.

Make a bunch of small accurate collars (say 1/4" thk with a set screw) place on the each end mill to restrict
Lots of companies (like Precise Bits) sell tools with plastic collars or rings already fitted. I gather they press-fit the cutters into the collars. Does anyone have any idea what plastic they use? It's pretty hard stuff.

I use ER collets as well but they are in collet chucks which fit in the spindle
Yes, my ER collets fit into a Kennelec BT-30 adapter, so that would in principle be possible. However, the top end of the BT-30 - the drawbar, is well inside the Z housing and it would be rather painful to access it each time. 'They' did not design the machine for easy access to the internals of the Z axis - but it is VERY robust. And those BT-30 fittings are 'not cheap' either ... Thing is, I use such a wide range of tools I would need dozens of BT-30 chucks. Ah well, I am having fun.

Cheers
Roger

All good stuff, i did see the collar idea on the mini-tooling for the engraver;)

I've got 12 ER32 chucks a couple of weldon holders which i don't really like, and my favourite Clarkson Autolok - this is useful because the location method of the tool makes any tool repeatable as they are pulled against a pip in the chuck that locates the centre-drilling in the tool end, only works on threaded tooling though.

I think I will have enough to get going now, this has been a real eye-opener so far, you never realise when being manual-only how much needs to be done to convert to even basic CNC.

Need to make an R8 tool rack now though, usually just keep them in a drawer but needing to be numbered changes that.

There is also the TTS/ER25 holders I have on the watch list - these would be great for drills. The main down-side with R8 is the length of the tool, I will have to program the table to go max Y++ at tool-change  to allow me to get the tool in and out easily, luckily not a problem with CNC

Oh yes, the CNC world is very different. Sometimes I think it would be easier to make a one-off on the manual lathe or mill, but I am fast learning that a) the CNC is much more accurate then me, b) correcting a mistake on the CNC only means a tweak to the program and a rerun, and changing significant parts of the design on the CNC is just a few more tweaks to the code and a rerun (all compared to redoing the whole thing on a manual).

Tool racks are essential imho, to keep stuff tidy, know just what i have got, prevent rusting, and avoid damage to cutting edges.

Cheers
Roger

Single-ended encoder signals in - you may need pull-up resistors there.

Cheers
Roger

Nope - just checked the manual and it outputs a voltage signal, resistors built-in

Yes Roger, i have discovered the easy-edit nature already

I could have made good use of CNC years back - things like making expansion links for traction engines - in the manual world this means making jigs and contraptions for milling massive curve radii - long chunks of plate on pivots and a rotary table under one end, hours to set up, sometimes a whole day, just to mill a slot and a couple of curves - this would be a doddle with CNC. Many new builders now get these parts wire eroded or water jet cut.

Many new builders now get these parts wire eroded or water jet cut.
Hum ... why don't they get the whole thing made for them? It is not as though it is a hobby, after all.

Cheers
Roger

Its just one of the really awkward bits to do i guess, I found the whole thing very educational, having a 300kg boiler on the bed of a Bridgeport really focuses the attention on clamping Or milling the centres of 48" rear wheels, 24" main gears....Happy days. I can't believe I even bought a massive horizontal mill just to cut gear teeth!

But, in the long run, if having some difficult bits pre-cut gets another engine in the build then it's all good;)

milling the centres of 48" rear wheels, 24" main gears.
Um - forgive me, but that sounds like a full-size engine. Is this a scale model?

Cheers
Roger

Its was a Half-size model

Apologies, the wheels were 36" not 48.

A few pics below;)