|Alan Gordon 4||03/07/2020 16:49:21|
|91 forum posts|
Hi Folks, Looking for advice on lathe dogs, I am not sure whether I should purchased "bent tail type" of the plain ones ? I am not sure what the benefits are or otherwise between the two types. any advice would be gratefully received.
|152 forum posts|
I think it depends on what type of drive plate you have. If your drive plate has a pin drive, get the straight ones. If it's got slots, get the bent type, but make sure the bend will engage with the slot.
|5932 forum posts|
Yet to use a faceplate on my big lathe or turn between centres myself ! I've not had the need to use either straight or bent dogs because if a job will fit in a chuck I'd much rather use that. In the good old days dogs were much used because chucks were expensive. Less call for dogs now, though they're still useful for some types of work, which might be your thing of course. However, if unsure about straight and bent dogs, maybe they aren't needed at all? Yet! When one is needed, you'll know exactly what to buy!
As Bo'sun explains the bent ones are meant to engage in a hole in the faceplate, which is fine and dandy if the two fit together. (Old lathes had a specially slotted plate for bent drive dogs, but general purpose faceplates are far more common nowadays.) A straight dog might be easier to fit if it has to be driven via a bolt or some other arrangement. Both types of dog might need to be fiddled into position.
Made some different dogs once for the one and only faceplate job I ever did on my mini-lathe. Clamps fouled the job so I had to shape some metal specially to suit. Never needed them again...
18318 forum posts
As I mostly prefer to turn a soft ctr from a piece of stock held in the chuck to ensure it is totally true I find that the cranked type work best for me as they will engage against one of the chuck jaws. I do have straight ones for when working with an MT ctr which can be driven by a stud fixed into the lathes spindle flange but only used once in a blue moon.
Edited By JasonB on 03/07/2020 18:23:23
|Ian P||03/07/2020 19:13:38|
2406 forum posts
I no longer have any lathe dogs as I found they never fitted or suited the things that I turned between centres.
Depending of what the job is I use toolmakers clamps or some other device like a shaft collar. When working on say, a large diameter thin (ish) wall tube with bungs in each end, I would just use duct tape to pick up the drive from the chuck body (with freshly turned centre).
Unless you know you are going to be doing work that will always fit in a dog, save your money for something else, or until you need them.
|Nigel Graham 2||03/07/2020 23:59:41|
|667 forum posts|
We all have our preferences, don't we?
I have various of these dogs and have used them all at various times. I admit they can occasionally be a faff to set up on awkward work, and now and then none seem the right size, but I am glad I have them.
Yes, sometimes I have met the diameter problem but that's a not a reason to dismiss them out of hand. I simply found ways to improvise...
... As when I turned my wagon's crankshaft. I had to make a pair of steel blocks to clamp to the shaft ends, with the appropriate centres; and to drive those I bolted step-blocks borrowed from the milling-machine, to the faceplate.
|Alan Gordon 4||04/07/2020 07:28:15|
|91 forum posts|
Thanks guys, much appreciated
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