Well, they might be now, but the clarkson(which I have never used) cost just over £100soo true.
i bought a mill about 2 yrs ago for 3k, since then i reckon ive spent the best part of 4-5k on tooling and im not there yet.
once you buy a mill, your doomed...
true enough, its something i personally dont have mostly because a half decent one is about 1k or thereabouts but maybe santa might cough up one sometime.
Lathes...
- Thread starter SuperTwo
- Start date
I
f you do, can you pas it on to me? I might use coolant then, at the moment, its rare to use it as the result is a shower for me!Il take that off don't worry
Il take that off don't worry
Very important to have a good flat level base. Even though they look to be solid cast, they can move or bend or crack or not cut true, I am told by a dockyard trained engineer
I thought they had to be bolted ridged with a special high accuracy level used.
I cant say too much, mine is in a artic trailer , just resting on the floor
Fowler VF
Member
- Location
- Herefordshire
You cant just plonk a lathe down and expect it work accurately! Its surpisingly easy to twist the bed, even though its all solid cast iron. It must be onto a good solid level floor and even then you will need to either use the adjusters on the feet and/or put in shims or packers. If the floor is at all uneven the lathe will settle into place and twist. You will never turn true if that happens. Use a high qaulity level when you put it in place, even then you need to do some test pieces and check for parallel, the way you bring it back into line is actually by adjusting the feet and deliberately putting a twist into it. Exception to this is some smaller tool lathes, like the Hardinge, in which the main frame and head stock are suspended and isolated form the main frame, these are self levelling (within reason) and don't need you to do any adjustment. Whether you bolt the lathe down or not is a matter of preference, a big heavy one is unlikely to move, but if you have adjusted and shimmed it all then bolting down makes sure none of that moves ever again.
Lots of ways of testing, lots of different thoughts on it; plenty of info on google, try here first:
http://www.practicalmachinist.com/vb/south-bend-lathes/best-way-level-lathe-205306/
Lots of ways of testing, lots of different thoughts on it; plenty of info on google, try here first:
http://www.practicalmachinist.com/vb/south-bend-lathes/best-way-level-lathe-205306/
Fowler VF
Member
- Location
- Herefordshire
And I don't buy the rubber belting idea either. Rubber matting for the operator, yes, but the machine? How can you be sure that your lathe has the same weight at each end/side? How do you know your rubber matting under each point will squash down by the same amount over time? Sounds like the easiest way possible to make sure that the lath settles down unevenly and starts going out of parallel after a few months/years of running. There are specialist rubber iso-mounts that might stay accurate, but unless your lathe has a dodgy bearing, or you are taking too big a cut it shouldn't be vibrating anyway. Rigidity is everything in machine tools, that's why the older heavier machines are so good.
A local engineering firm has six old holbrooks they stand over dowl pins, with rubber belting underneath the feet, and have done for many years, this firm is the one of the most respected in the area. Super marine, in Southampton had major problems with machine tooling during the war as the factory was for ever moving one way or another due to being built on estuary silt, releasing holding down bolts and rubber mountings went quite some way to solving the problem.
Fowler VF
Member
- Location
- Herefordshire
The Holbrook lathe is a very, very solid lathe, on a level floor its far less likely to twist than a lot of other makes. The Navy tested a range of lathes and plumped for the Holbrook, virtually every war time destroyer and warship had at least one Holbrook down in the bowels of the ship. These may well have been on rubber mounts to reduce vibration from the ships engines, maybe that's where the practice comes from? By and large solid floor and foundations, solid shimming, set it level and then do the test pieces to check still applies. There will always be exceptions where someone can achieve good results without this but for a new user of a lathe why introduce another variable? The example of the subsiding floor is actually a good example as to why rigidity is so important, how a machine bed can twist and how you need to take steps to ensure that the machine is properly levelled and do the test pieces.
Fowler VF
Member
- Location
- Herefordshire
Another bit of random information. Hardinge used to leave the bed castings outside for at least 6 months to "rest" i.e. normalise and ease out all the casting stresses before machining the rusty bases to true. They reckoned that their lathes were more resilient as a result and less likely to warp again.
All castings should be allowed to "season", if they are not, locked in stress comes out while machining is taking place, usually during the last cut! Resulting another for the scrap bin.A friend used to assemble engines in the motor trade, and he was always on about the blocks coming down the line which you couldn't get the crank or cam shafts to go into. Some accountant had decided that it was a waste of money "storing " castings!
TheTallGuy
Member
- Location
- Cambridgeshire
My Harrison was badly handled when loaded onto our trailer, bounced around for 100 miles & badly handled into place in the barn. I expected to have to spend a lot of time re-trueing it, nope - square and true on first go - I couldn't believe my luck. Only problem I have is keeping the tailstock on centre as the V grooves are worn.
Interesting. Adamant, submarine depot ship, had huge workshop areas, including a foundry on board, and I do believe that the lathes were Holbrooks, but memory is dim, I was only 16 when I joined her.I dont remember Venus,rebuilt WWII destroyer, having any machine tools, but was only aboard for two weeks sea training.Protector,Albion,Blake, and Tenby, all had I believe a "machining centre" which was a Lathe, Grinder, Drill and Mill,all based on one casting. I have no idea as to who made the things though.
Fowler VF
Member
- Location
- Herefordshire
Cant just recall where I picked up the link between the Navy and Holbrook but it was while I was looking at buying an old one with "War Finish" plates on it. Lots of machine tools were "war finish" even for civilian use i.e. fully functional but not cosmetically perfect with all the refinements like polish and paint, but the Holbrook lathes were definitely the preferred lathe for on board ships.
You might find this interesting, shows various ships workshops, including an on board foundry. Some debate about the various lathes shown but the consensus seems to be that at least on of them is a Holbrook. http://www.practicalmachinist.com/v...nd-history/photo-turning-fitting-shop-302257/
You might find this interesting, shows various ships workshops, including an on board foundry. Some debate about the various lathes shown but the consensus seems to be that at least on of them is a Holbrook. http://www.practicalmachinist.com/v...nd-history/photo-turning-fitting-shop-302257/
tomlad
Member
- Location
- nr. preston
I've been on hms Belfast sat on the Thames
That has impressive workshops
That has impressive workshops
I lived on Belfast for a year or so, while she was living ship for the reserve fleet maintenance section Never did get a good look around as all the machinery spaces etc were sealed off, and dehumidified.