Excerpts from Social Media

 Ronald Crowell Since you are new to this group, I'll assume you might find some info useful as follows. •1.a. The bearing stanchion has a shim under it so that its miter gear body will center on the lead screw for least drag. The 'U' shim (in the diagram, goes around the stanchion bolt) thickness must be determined for your new bearing stanchion. Note: It will not be necessary to repin the bearing stanchion to the apron with the original dowel pins, and in fact repinning it will likely locate it a small amount high or low causing it to drag on the screw. Leave the dowels out. •1b. So...first make sure your lead screw is straight and level (constant distance under and out) with the lathe bed ways and is the same distance its full length. Then, when the apron is bolted to the carriage and the bearing stanchion/miter gear assembly is loosely bolted to the back of the apron, move the carriage all the way to the left where the screw is least flexible and let the screw locate th...

Ronald Crowell: Facebook Group: Atlas and Craftsman Lathes Do not get an "ACME threaded rod", get an "ACME lead screw". They are different!! I don't know what McMaster-Carr might send you. Another ACME lead screw provider is Roton, and their pricing is competitive. . An "ACME lead screw" will have rolled threads with a more precisely controlled runout and machined smooth flat thread lands (meaning the flats on the OD). An ACME "threaded rod" will likely have non-machined rolled threads with the tell-tale rolling pinched lands that are not machined. The differences are readily apparent when from low cost vendors and a decent lead screw is more costly than a threaded rod. In addition, the surface finish of a quality ACME lead screw is almost a mirror..not so with a threaded rod. . McMaster-Carr does not specify run-out tolerance on their lead screws like a real specialized lead screw manufacturer, but unless you are making long high precision t...

  Troye Welch Satanite is good to fairly high temps, 3200 F IIRC, but it’s thin and brittle. What usually does it in is simple mechanical abrasion- lifting tongs scraping it or bumping into the RCF (wool) with the crucible- it will usually give, if you hit it hard enough and the satanite will crack and ultimately flame off. It’s easy to recoat, but a lot of people get complacent and run their furnace with bits of RCF exposed, which ends up being an inhalation hazard. Greenpatch 421 is more durable and goes on a little bit thicker, though still only a fraction of an inch- maybe 1/4 or so ( see http://zoellerforge.com/forgeparts.html ). The trade off you make for lower thermal mass is increased fragility. Neither better nor worse, just different with different pros and cons. I got some satanite from Zoeller forge years ago, but the last time I recoated my small propane RCF furnace, I used a product that BCS used to sell called a Matrikote. Very similar to satanite. Topped off with a...

Bruce Tremain Plaster and silica, anything from silica flour to sand depending on your application. Not all plasters are equal so if your plaster is softer (which alot is) then add about 5% or so of white Portland cement. You can add a little talc to make it more porous. One thing that I found a bit of a pain but very effective is to get ceramic fiber paper and add some of it to the water and then blend it together, the fibers provide excellent reinforcement against cracking. Start with 50/ 50. I suspect that it might perform even better if you drop the plaster down a little for higher temperature work.

  by Ronald Crowell Taper attachment and boring bar to get it close, then finish to proper size and depth with a Morse reamer. Just reaming a hole will not guarantee it is centered. Do step 1 below first. •1.  Regarding boring the initial taper with a boring bar and using the Atlas taper attachment, the taper attachment adds flexibility to the system and the very necessary precision will be more difficult (but still possible). The alternative is to simply use your compound set at the taper half angle and crank a boring bar through it by hand, but note that the compound travel is only about 2 inches. You will need to take "another bite" to get the full length of a MT2 (3-1/8" min) or MT3 (3-7/8" min). This adds a risk of a step imprecision. •Also, see my file in this group called " Precision Taper Turning.pdf ". Along with some setup advice it has a table of male Morse Taper dimensions at the end. Sorry, but I misplaced the proper female dimensions for the ...