Boiler Cradle Blocks
Posted: Thu Sep 28, 2017 9:03 pm
In any locomotive build project there is no end to the number of fixtures and accessories one can make. Boiler cradle blocks are just one of an endless stream of fixtures needed.
For certain boiler/smokebox machining operations, I find it most useful to heave the entire boiler/smokebox on to the table of the mill which then can be used as an ideal locating/reference surface for a host of machining operations.
Any good stout pieces of construction timber can be used for block material.
The first photo shows a completed pair of boiler cradle blocks made years ago which fit all of my 3/4" scale (Hudson ) boilers. In use, the boiler cradle blocks are secured directly to the table of the mill via the recessed bolts shown in the photo. The two holes drilled through the thickness of the blocks are to allow one to bolt the block blanks directly to the table of the mill when machining the cutout (with the the blocks sitting on parallels to raise them above the surface of the table of the mill of course).
However, since my 1" scale Yankee Shop Atlantic copper boiler has been silver soldered, I now need a larger set of boiler cradle blocks.
The second photo shows the preliminary operations to make a larger block. The cradle blank cutout is rough formed by bandsawing, extra long holdowns are needed and their purpose will be revealed later, the radius needed on the boring head is obtained through having a pointed center set in the middle hole of the boring head and a graduated scale to measure the radius of the cutting tool from the center of the boring head to the tip of the cutting tool. Ordinary cemented carbide tipped boring tools work fine here.
The third photo shows the setup with the boring head. If I had looked more closely at what I did the first time, I could have had a much simpler setup for this operation.
For certain boiler/smokebox machining operations, I find it most useful to heave the entire boiler/smokebox on to the table of the mill which then can be used as an ideal locating/reference surface for a host of machining operations.
Any good stout pieces of construction timber can be used for block material.
The first photo shows a completed pair of boiler cradle blocks made years ago which fit all of my 3/4" scale (Hudson ) boilers. In use, the boiler cradle blocks are secured directly to the table of the mill via the recessed bolts shown in the photo. The two holes drilled through the thickness of the blocks are to allow one to bolt the block blanks directly to the table of the mill when machining the cutout (with the the blocks sitting on parallels to raise them above the surface of the table of the mill of course).
However, since my 1" scale Yankee Shop Atlantic copper boiler has been silver soldered, I now need a larger set of boiler cradle blocks.
The second photo shows the preliminary operations to make a larger block. The cradle blank cutout is rough formed by bandsawing, extra long holdowns are needed and their purpose will be revealed later, the radius needed on the boring head is obtained through having a pointed center set in the middle hole of the boring head and a graduated scale to measure the radius of the cutting tool from the center of the boring head to the tip of the cutting tool. Ordinary cemented carbide tipped boring tools work fine here.
The third photo shows the setup with the boring head. If I had looked more closely at what I did the first time, I could have had a much simpler setup for this operation.