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View Full Version : How should I mount my Lathe(no not that way)







footz
3rd October 2008, 04:06 PM
The herc I got is on a home made angle iron affair with a 1/4" plate steel top. My floor at home is on a slope, the front I leveled off but it still slopes front to back .
The bench is extremely heavy, and with out the packing it still sits in place with a leg in the air, now it sits all four legs down but back tilted slightly. I was going to buy 4 adjustable feet as per pic. But after reading this link http://www.astronomiainumbria.org/advanced_internet_files/meccanica/easyweb.easynet.co.uk/_chrish/tsetup.htm

I wonder if I should get some long dyna bolts and bolt it securely to the ground and level it as well. I have read a few things which may be leading me down the perfectionist path. So far the way the herc cuts is perfect for what I am doing and more accurate then I am LOL.

bollie7
3rd October 2008, 04:47 PM
Mate, just level it up with packing. You don't really have to go to the expense of buying adjustable feet or the effort of fitting them. If you bolt it down, about 2 days after that you will discover it would have been better if you had put it in a slightly different place.LOL.You also run the risk of putting a twist in the bench which might transfer to the machine.
If you find you have to use a stack of packing, then get some thicker material thats close and finish with thinner stuff. Once you have got that all worked out, you can pull the stack out and glue then together with some spray contact if you are worried about the stack possibly moving. Being in the panel repair business, I'm sure you would have some spray contact laying around. You will probably find you won't even have to glue them but I have heard of it. Obviously you will use non compressable material for packing. ie metal. Don't forget the average aluminium can is about .005" thick and make great shims. (had to give it in imp as I couldn't find my metric mics). an hour or so and it'll be all done and you'll be turning again.
If you are putting it against a wall, be a good idea if you make your self a back chip tray if you don't already have one.You want it at least as high as the highest part of the machine with the bottom edge sitting in the tray under the lathe. Makes life so much easier. I suppos I should have said regardless of where you put the machine make a back chip tray.
Anyway have a good w/end
bollie7

footz
3rd October 2008, 06:02 PM
thanx I thought as much. Now I need to shim up the back of the bench and going by your calculations that will be a few cartons mmm don't think ill be doing any turning for a couple days need to have a carton party LOL. I dont have a chip tray but that is on the list. This weekend setting up mill with a catchment tray for coolant, and of course she who must be obeyed wants to go away for a night dammit

Keith_W
3rd October 2008, 07:12 PM
Must admit was seriously temped to have a funny with your title to your post.

As bollie7 says use packing to get your levels, make sure that they are solid packing as you dont want any shrinkage in the packing. Use a good quality level to level your lathe, if you can get or borrow an Engineers Level use it. Spend a little time making sure its level and check it again in a few weeks to see if ther has been any settleing, as this can transfer to the Lathe bed causeing twisting if not level.
I have found that the metal frames from old transformers the type that are lavered together make good shims.
P.S. Hope its a great night away with "she who must be obeyed", I have a Hyacinth clone here at times I feel.

Regards,
Keith.

billrule
6th October 2008, 10:01 PM
Requiem for Keith: if "she who must be obeyed" finds out about the Hyacinth crack, you're a dead hobbit! (who inherits the lathe?)

damian
7th October 2008, 08:49 AM
Couple of things.

Don't bolt it down. I don't understand why it has to be level. There is one criteria and one only for positioning and supporting a lathe, the pressure on all feet should be even and the table/support should NOT warp the bed.

If it were me I'd buy some 1/2" bolts and nuts, weld the nuts to your legs nd use the bolts to square up. Use more nuts to lock off if you want then slap paint on the lot.

You would be astounded how much difference a twisted support make to a lathe's acuracy. It'll cut S's if it's wrong.

Decide where you want it and take the time to set it up properly. Then never move it.

2c.

Greg Q
7th October 2008, 09:11 AM
Couple of things.

Don't bolt it down. I don't understand why it has to be level..... There is one criteria and one only for positioning and supporting a lathe, the pressure on all feet should be even and the table/support should NOT warp the bed.


Decide where you want it and take the time to set it up properly. Then never move it.

2c.

It doesn't have to be level at all. They have lathes on ships after all. As you point out though, it does have to be free of twist in the bed ways. Since the horizon makes a handy reference, a precision level is the cheapest*, most reliable instrument available to assure a zero twist condition.

WRT to never moving it: Also make sure that the machine is away from direct sunlight too as temperature changes will temporarily warp the bed. So will changes in the ground water which will cause your floor to move. (It's always some damned thing)

I spoke with one guy who does ultra-precision machining...they check the lathe's level twice a day, sometimes spending two hours tweaking. (They make very high cost parts, the time is figured into the price)

*cheapest but still expensive. Starrett 199 is one example. The European ones all seem to have a grooved bottom. The Starrett and Tumico levels have flat bottoms, which make them more useful tools for checking levels longitudinally.

I don't know for sure, but I imagine that you could get the same results with a Starrett 98 level (for example) and then fine tuning by checking diameters on a test piece.

(Starrett 98 has an accuracy of 0.005 inches per foot, a 199 is ten times more accurate. It is so sensitive that you cannot breathe on it during use...the heat will screw up the reading.)

Greg

jmk89
7th October 2008, 09:18 AM
Harold Hall suggests that jacking nuts are better than shims.

When I get around to mounting my Zyto, I propose to have 1/4" steel plates screwed onto the wooden bench surface under the feet (one plate at each end). Then I will insert lag screws (http://elraco.com.au/product_thumb.php?img=images/LAG51663.jpg&w=78&h=150 (http://javascript<b></b>:popupWindow('http://elraco.com.au/popup_image.php?pID=1643'))) through clearance holes in the steel plate into the bench top, put two nuts on the metal-threaded part then put the lathe feet on the nuts and put a nut on top. Any warp can be removed by loosening the top nut and the locking nut and moving the jacking nut and then tightening the whole thing up.

It is also worth reading the chapter on setting up in Sparey, The Amateur Lathe. He shows how you can get the setup right using a dial indicator and a round rod in the chuck. This demonstrates the point that the issue is making sure that the lathe bed is straight - if it is level, that's nice, but it has to be straight.

.RC.
7th October 2008, 10:06 AM
I use a Starrett 98 level to level my machines...

I originally borrowed a precision level with 0.02mm/m accuracy...It took me hours to get the lathe level with it due to it's extreme accuracy...

Woodwould
7th October 2008, 10:21 AM
My method was to attach a short length of allthread at each foot position on the (wooden) lathe bench and secure them with locknuts either side of the bench top.

I pushed 'tophat' shaped rubber insulators over the exposed allthread and re-drilled the holes in the lathe's feet to suit the bushes. The lathe was lowered onto the bushes, followed by further rubber insulators and then topped off with washers and locking nuts.

The locking nuts were just tight enough to keep the whole lot together. The bushes allowed the lathe relative freedom yet anchored it on the bench to prevent it 'walking' when turning large unballanced items.

damian
7th October 2008, 10:30 AM
Oh right. When I saw level I assumed you meant it mattered :) Yeah that's a good way of getting it straight. I just do test cuts, but whatever...

footz
7th October 2008, 01:08 PM
Well thanx all
I am going to drill 4 holes in the 4 corners and do the bolt thingy like Damian pointed out. Saves me buying anything. I will just use a spirit level to get it set up but making sure there is no twist, I gather I just loosen the bolts holding the lathe to the table and see if it sits flat? The original hercus bench are they worth getting ? seems small but I like the size of the tray. My bench has a tray but only under the cutting area but fairly deep. Some one mentioned before about not bothering with a hercus bench. I could always get a tray pressed out of galv the size I want anyway. I luv the comment about lathes on ships hehe I never thought about that.

damian
7th October 2008, 04:52 PM
One approach might be to unbolt the lathe and true the bench till al the lathe feet are touching. Leave the bed bolts in but loose, fiddle teh bench feet till it's all good then retighten your bed, checking it as you go.

Or, screw down your bench till all the feet are about the same pressure than shim the bed till it's good.

I don't like the enclosed cabinet cos they are harder to clean around than an open type. YMMV. The cabinets/drawers are handy though, esp for avoiding losing tooling...

Gavin Newman
7th October 2008, 05:13 PM
Question is, where do you get an engineer's level that doesn't cost an arm and a leg (especially in Adelaide). Given the limited number of times it's going to get used it's a pity you can't rent one from time to time.

jmk89
7th October 2008, 06:05 PM
You don't need a level. Use a dial indicator and a rod in the chuck. If when you turn the chuck by hand the dial indicator moves too much, then you need to alter one of the feet. Once it turns properly on this test, it is likely to be close enough. After all, the purpose of this is just to ensure that the bed and the spindle are parallel to each other.

Keith_W
7th October 2008, 06:16 PM
Gavin Newman, I was lucky enough to get a Starret Level free from a friend when he had died, sure miss the sound advice he gave when he was alive.
I have seen Starrets come up on ebay from time to time so you may get one off there relatively cheap, they certainly worth having.

Regards,
Keith.

footz
7th October 2008, 08:56 PM
I wish they where cheap I bid on one last weekand it sold for $294.00. More then I felt like spending on something to use once in a blue moon, and remember what happens on boats LOL

.RC.
7th October 2008, 09:43 PM
That 12" Starrett 98 on ebay went stupidly expensive...I would expect to pay that much for a new 0.02mm/m level..

I paid $90 for my 8" brand new on ebay years ago.. They are even cheaper in the US..

bollie7
8th October 2008, 10:00 AM
footz
Its great for everyone to talk about using hideously expensive precision levels but lets get real. A builders spirit level that you can buy in Bunnings for, I dunno, maybe, $30, will do the job fine. Its a Hercus on a fabricated steel frame,it will move around with the weather. you don't need the degree of accuracy that a precision level has. Sure if you can get one cheap grab it but other wise don't bother. the main thing, as others have said, is to make sure there is no twist etc in the bed and there are no "soft" feet on the bench. A builders level will do that no worries.
You could even use a water level to do the job.
I just used my builders level to set my lathe up. Length ways on the bed and across the bed at each end. Took me about 30 minutes and I can easily get .0005" on the machine which is good enough for everything I do.
Enjoy your machine.

regards

bollie7

footz
8th October 2008, 10:25 AM
Aye I hear ya Bollie, I think its like most things you can go to town and spend thousands. I will be doing the bolt thing, more then enough for me. And dam with my accuracy I think even if it had a twist I wouldn't know heheh. At the moment I am only machining small stuff, nothing long at the moment that needs any real accuracy. But geez it sure is fun!

Thanx all to the advice, as it has opened up these old eyes of mine, now if I can only stop buying and making more tooling and get onto some projects...................

Gavin Newman
8th October 2008, 10:33 AM
Gene

My missus reckons that I use the lathe to make tooling for the mill and that I use the mill to make gadgets for the lathe...she's joking though (I hope)

I've aligned my lathe as best I can using a normal spirit level, like you I haven't turned anything long yet. One of these days I intend to use the Rollie's Dads Method ( http://www.machinery.josemeneses.com/library/rollies_dads_method.pdf )to fine tune the alignment but thus far it hasn't been an issue.

Rgds - Gavin

bollie7
8th October 2008, 10:56 AM
.......But geez it sure is fun!.....
and making more tooling and get onto some projects...................
Years ago I used to read the "Model Engineer" mag and think that a lot of the old blokes seemed to spend all their time making tools, jigs & fixtures for their machines and not actually "making" anything. I couldn't understand it. Well now, with a lot more summers behind me, I can understand it. I'm even starting to do a bit of it myself LOL. Doesn't really matter if you are making tools or making projects. For me its the pleasure of the actual making, not so much the end use. Standing there watching a lathe chuck spinning or a mill cutter twirling without having to worry about a deadline to meet or a boss on your back can be very therapeutic.
Actually a shaper is one you have to be careful with. Watching the ram go back an forth can be a bit hypnotic. When I was an apprentice one of the jobs we had to do was to prepare plates for the boilermaker aprentices to practise welding on. There were a couple of sizes but all were around 600mm long X about 100 wide X about 12mm thick. There was a big old WW1 vintage shaper with about a 800 mm stroke that we used. held the plates ( about 12 at a time, longwise to the ram) in the vise and machined one side flat. It wasn't uncommon to fall into a bit of a daze while watching the machine. There was another shaper next to this doing similar work so we used to keep an eye on each other so that we didn't fall asleep on our feet. Seriously, I'm not having a joke here.

bollie7

Gavin Newman
8th October 2008, 10:59 AM
Bollie's on the money regarding the hypnotic effect, I was using a surface grinder to finish off some parallels the other day and it's amazing how easy it is to lose concentration with the table moving back and forth and in and out. Must be the advancing years?

wannabe
8th October 2008, 11:00 AM
now if I can only stop buying and making more tooling and get onto some projects...................
It's terrible isn't it. You start doing something and then have to stop to make a tool to make the tool. It's like Simso's Pan Brake folder. I saw that nearly a year ago and thought I'd like one of those. Looked at the radius curves (need rotary table), 47mm dia hole, (need boring head), 20 & 25mm holes (need large drills). The list goes on. 12 months down the track and I'm ready to start it.
As has been said before. Buying the machine is only the start. Then the expensive stuff starts.

damian
8th October 2008, 11:23 AM
You wouldn't be the first :D, but gee shapers are handy. Wish I had a little one at home.

bollie7
8th October 2008, 12:23 PM
You wouldn't be the first :D, but gee shapers are handy. Wish I had a little one at home.

Damian,
Funny that. is this little enough?
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=170269859804&ssPageName=ADME:B:EF:AU:1123

bollie7

damian
8th October 2008, 01:31 PM
Argh! Why did you have to show me that ? :D

Gosford is about 10 hours drive. Hm.

footz
8th October 2008, 01:47 PM
Well I better not bid on that item then!, and freight would be costly lol

damian
8th October 2008, 02:18 PM
I should just make a slotting attachment for the mill. They are so handy for making splines and keyways. Yeah I know you can use a broach but a slotting attachment is so versatile.

bollie7
8th October 2008, 02:41 PM
one of these is even better
http://cgi.ebay.com.au/Slotting-Machine_W0QQitemZ150301334792QQihZ005QQcategoryZ92083QQtcZphotoQQssPageNameZWDVWQQrdZ1QQcmdZViewItem
bollie7

damian
8th October 2008, 02:54 PM
Argh! Stop it! Arrrgh....:D