Denford Starmill - replacing spindle

[Doddy]

A photo, to hopefully explain what it is I have. As previously mentioned, ATC was removed, so the spindle has a ??? sized bolt acting as a draw bolt for the BT35 (got it wrong the first time) tool holder. This isn't a problem for me as I use a BT35/ER32 toolholder for most things (though this requires a spindle lock).




Edit: Remove the following paragraph (daft idea), replace with that, below.

The height of the material on the bottom of the head, holding the bearings, is something like 35mm, and clearly not finished to be readily used as a mount. There are some M8 holes tapped on the underside of the head which I could mount a plate (with a cut-out for the existing spindle), take that to the edge of the head and then mount a plate perpendicular as a mount for another spindle. That might be my preferred route. Would that be stiff enough with, say, 15mm 6082? Actually, thinking about it, it could be a good opportunity for me to practice my welding (got a tig, somewhere), I guess 5mm mild steel plate would be stiffer than ali (I think I need to be mindful of the weight here, can't go silly) - extended out to the front of the head with a fillet plate joining the horizontal and vertical members

Ignore the above paragraph. Next crazy idea is this: There're the ground ways on the vertical column that must be perpendicular and flat. What's stopping me removing the head, drilling/tapping and mounting supported rails to the ways (this is the only bit I'm hesitant on at this time, but this shouldn't mean that I can't recover the machine at a later time - a few tapped holes wouldn't affect the geometry of the ways?), and mounting a simply carriage, onto which would bolt the standard chinese spindle mount. That all feels very do-able, allows me to maintain the offset from the column to the centre of the spindle (so as to not lose out on the Y traverse), and is easily machinable with what I have to hand (apart from the supported rails and carriages... minor point). I'd lose the low-speed of the existing spindle, but I hate using the machine on steel (it doesn't feel strong enough, too much chatter). This is 90% inspired by Jazz's idea of replacing the head but avoids some of the problems that I envisage with the dovetail and suitable materials.