I concur with No going back,to preserve the look of this old machine, It is too much of a very useful historical machine tool to alter, + being most useful, What I would do is rig up a gallows just behind the machine, having the countershaft pulley behind & above the three machine pulleys, your Baldwin looks to be a two belt machine, One belt" Open Belt " drives the table intowards the back of the machine, on the cutting stroke, i e, work proceeding towards the tool, The other belt the "Crossed Belt or Return Belt" having a twist set in it drives the table on the return stroke Out towards the front of the machine
If this little machine is confgured as I say, the two outer pulleys will be idlers on the shaft, & the inside pulley keyed, Thus doing the work, The belts parked & running on the outside pulleys when not cutting , but one of them engaged on the inner pulley depending on table direction when working, I would imagine from past experience, when I used to operate a much bigger machine equally ancient but similar ? design the speed of your pulleys should be about 80 revs /minute , But do a gear tooth count , Firstly call the gear on your belt pulley the first motion gear , The next count the teeth, second motion gear, & so on till you come to the little gear that drives the rack , usually it is configured as 1/1 ratio, Let me know the teeth count on each gear, Also move or turn the driving pulley by hand to see what direction the table moves, Usually the wheel moves towards the frontof the machine in rotation, The one thing to be carefully observed is that the belt forks push on the belts on the leading side of the belts ( The side which enters the pulley or pulling side)
I believe your 1/2 horse power motor should be strong enough, I will see if I can dredge up any further info.
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