Milling machine for 10-1/4 in. gauge

Now I know that my lathe is big enough, I hope this may be a simple enough question as well but could anyone please advise what size milling machine (at a minimum) would be needed to build an engine of Britannia size in 10-1/4 gauge?

If I were taking on such a task, I would want at least a bridgeport size.

keep us posted on progress

Shaun

If you have the space/budget a Bridgeport or one of its clones. I would not like to be without my Bridgeport.

Assuming you buy in the frames laser cut it ought to be possible to handle the work on the larger dovetail column bench machines such one of the sub Bridgeport size hobby knee mills. Using the Chester site as convenient reference the Lux, Super Lux, 626, 830 VS or 830 VS-R are possible candidates. Other suppliers have similar options. Some creativity in mounting larger components may be needed and, possibly, taking two bites to cover a surface when you'd rather do it in one hit. Y-axis travel is usually a limitation with this class of machine. Dovetail column machines in particular generally only have enough Y travel for the spindle centre line to cover about 3/4 of the table Y depth. The 830 VS-R, with its scaled down round ram Bridgeport configuration scores here due to the ability to adjust the head in the Y plane. There is also an attractive scaled down Bridgeport dovetail ram machine around which is probably a good choice if you don't have room for a Bridgeport.

Of course the prices of such machines are up in good used Bridgeport territory so if you can fit it in its the obvious machine to go for. I went from a short table Lux to a 49" table Bridgeport and the extra space made life unbelievably easier. In theory pretty much everything I voluntarily do could be fitted into the working envelope of the old Lux but most would have been something of a battle. No getting away from the fact that mills and milling jobs tend to sprawl. Its probably not unfair to say that if the work envelope you intend to use is X by Y by Z its desirable to have 3X by 2Y by 1 1/2 Z of space available. Then there is the extra Z needed for tool changes, switching from drills in chuck to milling cutters in collets ect ect. There is a darn good reasons why a Bridgeport is considered about the minimum for general purpose 12" to the foot scale work. Another point in favour of professional market rather than hobby market machine of these sizes is the extra durability and refinements required by a machine that has to earn its living in full time work. Hobby market machines are inevitably price constrained and, with the best will in the world, most hobby buyers have to accept limitations if the new machine price is to be in reach.

Really you have to do your homework when going below Bridgeport size for these big models. Perfectly possible to manage with a well chosen smaller machine but with the number of parts involved there is much to be said for making life easy.

Clive.

I would go for Bridgeport size minimum,the snag with smaller mills is they tend to wobble and vibrate when trying to take reasonable cuts and it is easier to keep everything true and square on a larger machine as vices and angle plates and other equipment are also larger and more rigid. The turret mill also has the advantage of the head swinging round to reach the ends of the table,the ability for the head to rotate a full 90 degrees so that the spindle is parallel to the table allowing horizontal boring,check is very useful ,a number of clone turret mills only swing to 45 degrees. I have an Elliot Milmor excellent capacity, 30 int spindle,ideal for a large loco. My ideal turret mill would be a TOS with 40 int spindle and power feeds on turret and power feeds on xyz axes. they are big machines ,power feed on the z axis is better for boring with the turret quill locked. plus as one gets older its winding the table up that gets hard work. I also have a Adcock and Shipley 2E, horizontal with vertical head both having 40 int spindles this machine allows real milling with inch plus end mills,plus a range of large side and face cutters on a horizontal arbour. If you have the space I found it it more economical to buy these two machines rather than a good Bridgeport,

Buy my Harrison. You would be my wife's best friend and I would be pretty happy too. Dro fitted😉

Bri

Thank you for your comments everyone, you have given me some useful information. Certainly a bridgeport sounds the way to go, I think I would just about have room for a A&S but space is tight. Good to know my options.

Ralph, interested in your build. Just start to budget for patterns !!