# Anyone familiar with Schroeder dog clutch



## Don Pittman (Dec 15, 2019)

Hi,

Jim Schroeder adapted G Meeks threading dog clutch mechanism to fit his Grizzly 10x22 lathe and the plans are available in a machinist publication.  It looks like a great modification.  I would like to try to make this modification to my lathe which is similar but not exact.  
However I think I need someone that is similar with the mechanism to guide me on what likely needs to be changed in order for it to work for my lathe.

The main difference I am dealing with is my lathe is a Craftex 10x22 version which came from factory with the reverse tumbler.  It also has module 1.0 gears as opposed to the module 1.5 gears in Schroeder plans.  

Obviously I would need to use the correct gears but do other components stay the same?  I guess I eliminate the factory reverse tumbler?  
I imagine that unless somebody is very familiar with this setup, it will be very hard to advise me but I thought it might be worth a try.  
Thank you


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## pete (Jun 15, 2020)

Yes as you've already figured out the gear module would need to be the same as what your lathe currently has. I can't really help much with your questions, but when changing published design drawings to fit your particular equipment I view anything like this as a prototyping exercise. Industry will very often use much cheaper materials in the initial stages of a design to save on costs until that design is at least semi finalized. They'll even use what's called Machinable Wax to first prove complex cnc programs before moving to the actual metal parts. In a home shop with an unproven concept or idea and where numerous changes might be required until we get it to bolt in place and work as required we can do much the same. With any design I'm not totally sure about I'll use either glued up pieces of plywood or hard woods since it's quite fast to machine, fairly easy on cutting tools, a whole lot cheaper than metal ,and any unplanned mistakes or design changes can be quickly worked around simply by gluing on more wood. Hardwoods can even be threaded using normal taps and if a bit more durability is needed then wicking CA glue into the threads will help a lot.Yes machining wood makes a mess, but my personal opinion is the trade offs with it as a starting material are worth while against it's cost and speed of machining. It's usually durable enough to at least prove the changed design will fit in the available space and work as long as you didn't try to cut threads under power with it. For something like what your trying to do it's what I would use. If your buying the extra module 1.0 gears then those are a fixed part of the design so buy those first since they can also be used with your wooden prototype parts. I don't have my copy of his book handy, but if I recall correctly Mr. Meek retained the tumbler reverse gearing in at least the design he came up with for the Myford Super 7 lathe. So if my memory isn't faulty you should still be able to retain yours if you can find enough room to fit the additional parts in.

If you succeed with this I'd highly recommend having a look at the George Thomas designed geared and lever operated top slide published in his book The Model Engineer's Workshop Manual. Hemingway Kits Geared and Retracting Topslide for Myford S7 It was specifically designed to both help and speed up thread cutting and also help with less interference between the top slide hand wheel and the tail stock.  It would make a very good addition to the Meek designed dog clutch. With a bit of redesign effort it could be made to work on probably any lathe of about 7" swing and up. With both additions you'd have roughly the same threading capability as one of the Hardinge HLV lathes have and there well known for the high speed threading.  It would take a couple of new gears, a longer and reversed direction feed screw and nut to fit your own application. But none of that is very hard to find.


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