DURING the late war, machines whichrequired massive castings in theirdesign were built with beds of cement orconcrete, simplifying the work of con-struction, and providing a means of mak-ing very heavy machines with a minimumof large castings. This method can beadapted to the use of the mechanic in thesmall shop, and by using a combination ofcement and cold-rolled steel, small ma-chines can be constructed sufficientlystrong to stand a considerable amount ofheavy work, while eliminating entirely abody casting.

The bench miller described in this articleis an example of this method; only onecasting is employed, and the rest of themachine is of such construction that butfew simple tools, and little machine work,are required in the building of it.

The steel, flat and round, which can beobtained from any steel merchant, is firstcarefully checked for straightness andparallelism, using a good straightedge and

for the bolts are 3/8 in. deep, and tappedwith a 1/4-in. bottoming tap. The baseis a piece of 1/2-in. cold-rolled steel, oriron, and is fastened to the front slideby means of two 1/4-in. flat-head screws,countersinking the slide for the heads,so that they will be flush with thesurface. The spindle and overarm pipesare fastened to the front slide by means offlanges, the pipes being boredthe over-arm pipe to a sliding fit for a piece ofl 1/4-in. cold-rolled steel, the spindle pipeto fit the two bronze bushings which formthe spindle bearings. These pipes mustbe fitted absolutely square with the frontslide. A bolt and pipe, with a flat pieceof steel, will be seen at the bottom of thebase; these form a brace for that part ofthe slide projecting below the bench top,the flat piece also forming a bearing forthe elevating screw. When this brace, thebase, front slide, and pipes have beenassembled, the next operation is the pour-ing of the cement. The anchor bolts are

a micrometer cali-per; if any bentspots are discerni-ble, straighten care-fully, and if thickspots occur in theslides, scrape themoff until a level sur-face is obtained.The holes in thefront slide and baseshould then be laidoff and drilled, in-cluding the holesfor the spindle andoverarm, and the 1/4-in. holes for the an-chor bolts. Theseanchor bolts are 1/4-in. stove bolts ofvarying lengths, asshown in the smallerdrawing, and areplaced so that theheads will be stag-gered, to distributethe hold and strainsmore evenly in thecement. The holes

i n t e r w o u n d withsoft-iron wire, asshown, and the formis placed in position,and clamped rigidly.A mixture of 1 partcement to 3 partsclean, sharp sandhas proved ideal forthis purpose; dur-ing the pouring,the spaces betweenthe screws, and alledges and corners,must be thoroughlypoked with a knife,or other sharp-pointed tool, to in-sure that the cementreaches every part.After pouring, leveloff the surface, andthen lay the assem-bly aside to season;this is a very im-portant part of theconstruction, the ce-ment being wettedat least twice a day

3557

The Main-Body Casting is Poured in a Mold Madeof Soft Pine, the Top of the Front Slide beingShaped to Conform to the Contour of the Casting

toshibaSticky Note

pattern is built for the knee casting,which is made of soft gray iron, andmachined as indicated. On the top of theknee is the main carriage slide; it ismachined very carefully on the edges andfaces, and must be perfectly square in alldirections. On the vertical sides of thisslide are screwed the angle members, twofor the table slide and two for the car-riage slide. These angle members aremade of 3/16-in. angle iron, filed and fittedwith great care, a cut being taken throughthe inside fillet, on the shaper, before fit-ting; 1/4,-in. round-head screws hold themto the carriage slide. The table is built up

round-head screws. The equipment neces-sary, such as arbors, centers, and a smallvise with a homemade swivel base, can bemade up as required. A good chuckshould form part of the equipment, andshould be fitted with a flange threaded tofit the spindle nose.

While foot power may be used with themachine, a small 1/4-hp. motor, drivingthrough a countershaft and cone pulleymounted directly over the machine, isadvised. The cone pulley should be of thesame size as the one on the miller.

The builder of this miller will have asplendid little tool, at small cost.

p a r t s maybe made up.The spindles h o u l d beturned andb o r e d ,using a No.2 Morse ta-per in thenose, andcutting thethread forthe chuck,which is 1/16-in. pitch;b r o n z eb u s h i n g sare used fort h e b e a r -ings, beingt u r n e d tom a k e apress fit inthe spindlep i p e . Athree-stepcone pulleyis t u r n e dto the di-m e n s i o n ss h o w n ,and is fas-tened tothe spindleby a safetysetscrew. As i m p l e

j o b c a nb e s t b ed o n e b yusing a fewrivets tohold the as-sembly,while per-forming thedrilling andtapping op-e r a t i o n s .The T-slotin the tablepermits theuse of 3/8-in. bolts, tohold a vise,or the vari-ous fixturesused on themachine.

All screwsused on thev e r t i c a l ,l o n g i t u -d i n a l , andcrossfeeds,are turnedout of cold-rolled steel,and run inb r a s s o rb r o n z en u t s , fas-tened to theslides with

of cold-rolled steel, as shown in the detaildrawing, the various pieces being held to-gether with 1/4 in. flat-head screws. This

for a period of about a week. While the ce-ment is thus seasoning, the screws, slides,spindle, knee, and various other component

3558 P O P U L A R M E C H A N I C S