tramming a lathe...chicken or the egg...which came first

[eskimo]

what comes first
have found methods of how to tram lathe using a test bar

and then I found info on How to fit a chuck.

For the later it tells one to machine the face plate on the lathe prior to fitting the chuck.

Now to my way of thinking if one machines the face plate wont the face plate be out of square to the bed if the head stock spindle is not parallel to the bed

So what does one do first....... and how?

[Stustoys]

Tram the head first with a test bar in the taper of the spindle.(but this is something you shouldnt have to do)
This assumes you have a proper test bar.
Or are you talking about using rollie's dad's method of aligning the bed?
Is this is your old/"new" lathe?

[eskimo]

Is this is your old/"new" lathe?

yeah...thats the one (the toy one)...the one out of the box....she said to me over the weekend..dont you think you've got too much crap in here, .. but I think she was refering to the 2nd hand bandsaw I just got hahaha.....should have got the lathe out a long long time ago...she was standing next to it talking to me and didnt even notice how bright and shiny it was......:(

I was thinking of Rollie's method unless there is something easier for me

The face plate is <0.01mm when rotating it ...a bright mild steel bar when measured about 75mm away from the jaws is 0.09mm.....tried roating the chuck on the face plate and hitting it with soaft face hammer etc but stays the same...do I need a better chuck.?

[Stustoys]

lol well I'm glad you are still with us

Ok so your leveling the lathe then? Do you have a good level?

pictures eskimo

You're mounting a 3 jaw chuck to the face plate?
You can mount the chuck on the face plate 3 positions right?
When you move the chuck from one position to the next, does the high spot stay in the same place v the spindle or move around as you move the chuck? This should tell you if it is the chuck mounting or the chuck itself that is the problem.

Stuart

[Dave J]

Hi Eskimo,
So your didn't get caught out with the lathe.:2tsup:lol

It wont matter if you take a light skim off the face plate. If the lathe spindle is out (which wont be much), it will turn it a slight concave or convex, but will still be true enough to bolt the chuck on to take measurements of the spindle.

Dave

[eskimo]

You're mounting a 3 jaw chuck to the face plate?
You can mount the chuck on the face plate 3 positions right?
When you move the chuck from one position to the next, does the high spot stay in the same place v the spindle or move around as you move the chuck? This should tell you if it is the chuck mounting or the chuck itself that is the problem.

Stuart
Ta Stuart

yes its a 3 jaw
the high spot follows the chuck...not the faceplate
moved the steel bar 180 degrees and the high spot still in same place with the chuck..

this says the chuck is at fault...?

are the cheapies at H&F anygood?

[eskimo]

(which wont be much),

this is not an AL960 Dave,...going by the some of the other stuff I have bought I wouldnt be suprised if it was worse than what one should expect
You have a Fuerda from H&F dont you Dave...is it the cheapie or one of the dear ones
How do you find it?

[Dave J]

Before doing anything take the chuck apart and give it a good clean out. If nothing changes you could follow the idea below to true it up.

If the lathe came with a 4 jaw you could machine a bar (the larger the better) in it so it runs true, then clamp your 3 jaw onto the bar backwards and take a skim off the back of it.
If you don't have a 4 jaw you could weld a bar to a piece plate that is big enough to bolt to the back plate or face plate, bolt it on the face plate and machine it true to mount the chuck as above.
I have trued up a few chucks and the cast iron cuts like butter as their usually pretty good cast.

Dave

[Stustoys]

What's the run out as close as you can get to the jaws?
What was your lathe again? AL54B? I cant seem to find it.

Like dave says clean it. If its anything like mine it will need it. Careful of the burrs though.
Then you could try tightening the jaws with one socket check run out, then loosen and tight with the next socket, check run out, repeat for the third socket. That may change the run out.
You could also try shifting the jaws around to the other slots. I've never bothered to do this with mine, but I've read that some chucks like there jaws in a certain slot and the chuck tightened with a certain socket.

Stuart

[eskimo]

Ok...i'll strip and clean it
just noticed that it is a Fuerda...

Dave...you want me to do what....weld.......hahahahaha
you've never seen me weld have you...lol
but I will try.... if cleaning doesnt help...I'll keep my fingers crossed

Its a BB25-1 Stuart...a toy!!!

The test indicator says .04 at about 10mm out from chuck

[pipeclay]

Stuart.isnt the Chuck in question a 3 jaw chuck,standard self centreing.

If this is the case the Jaws will only be able to go into there correct pocket for the Chuck to run "true".

Unless this is not a Scroll type chuck.

Maybe it has bolt-on jaws,in this case you probably could interchange the Jaws,but not advised as these type of Jaws are usually numbered,as should be the Jaws for a Self Centreing chuck.

Never really heard of or viewed somebody checking Jaw runout by tightening the Jaws from 1 key hole then moving to the next and so on.

Not saying that there might be some slight change, though doubtfull as the key hole turns the Scroll.


Eskimo if its only a Standard 3 Jaw Self Centreing Chuck give it a pull apart if it has a back plate check for burs or rubbish,check the Thread if its a Screw on type.

If its a Bolt-on type check the holes for burs.

If you clean it and check it put it back together and its still running out just live with it,even if you purchase another similar 3 Jaw chuck it will still run out just maybe not as much.

If you do pull it apart mark the Back Plate ,body and anything else that you pull apart so that it goes back together the same way.

[Stustoys]

Stuart.isnt the Chuck in question a 3 jaw chuck,standard self centreing.

Hi pipeclay Yes I believe it is.


If this is the case the Jaws will only be able to go into there correct pocket for the Chuck to run "true".

No, the jaws can go in any pocket(slot), the order of the jaws has to be right but you can start at any pocket.


Unless this is not a Scroll type chuck.

Maybe it has bolt-on jaws,in this case you probably could interchange the Jaws,but not advised as these type of Jaws are usually numbered,as should be the Jaws for a Self Centreing chuck.

Never really heard of or viewed somebody checking Jaw runout by tightening the Jaws from 1 key hole then moving to the next and so on.

Not saying that there might be some slight change, though doubtfull as the key hole turns the Scroll.

The scroll will have some clearance and in theory this will mean that one keyhole should be better than the other two......... as I said I've never tried this but if I remember I'll measure it tomorrow just out of interest.



Eskimo The 0.04 reading, did you take that before cleaning or after?
What have you mounted the lathe on?

Stuart

[eskimo]

did you all know that Fuerda make chucks to 2 standards....with the best one being DIN and the second one Chinese Accuracy Standard.....i think i was robbed cos i reckon i got less than that

FUERDA-Workholding Solutions (http://www.cnfed.com/pro.asp)


so its the DK type I want.....?...lol...no one told me!!!

Stuart the error was before .....cleaned the chuck and no difference...same as before...
its as rough as guts inside......I'd be there for a year polishing it to get the rough machining marks...hold on ...was it machined...lol...

[Stustoys]

Hi eskimo
Do you have a 4 jaw? You could try putting that on, centering the bar, then check the run out 75mm from it. Not sure I would be worried about 0.04 run out, in fact I've never checked the run out on my 3 jaw.
Stuart

[eskimo]

Hi eskimo
Do you have a 4 jaw? You could try putting that on, centering the bar, then check the run out 75mm from it. Not sure I would be worried about 0.04 run out, in fact I've never checked the run out on my 3 jaw.
Stuart

Nope...dont have a 4 jaw

But cant be sure the 1inch barstock I have is not bent so I am going to make a test bar which now poses this question....

My chuck backing plate is not removable..the spindle incorporates the plate

the spindle taper runout was <.005mm.... could hardly see the needle move..if I did it right..lol

so how do I machine between centres with out an adaptable face plate?
the chuck wont accept the passing thru of a 4MT so that means the chuck has to come off...do I need to make a plate, one that bolts to the chuck backing plate or is there another method I could consider

its a standard looking backing plate with 3 bolt holes for the chuck and 1 hole to get at the bolts for cover plate of the front bearing

[Stustoys]

Are you sure it isn't a screw on chuck eskimo?
Why (at the minute) do you want to turn between centers? You could most likely put a bolt in one of the holes on the plate thats there already and make a dog that presses against it. I assume you don't have any dogs? Some pictures would help.
Stuart

[eskimo]

Are you sure it isn't a screw on chuck eskimo?
Why (at the minute) do you want to turn between centers? You could most likely put a bolt in one of the holes on the plate thats there already and make a dog that presses against it. I assume you don't have any dogs? Some pictures would help.
Stuart

I want to turn between centres so that I can make a test bar for tramming the lathe as per this....to start afresh with someting I know is true..well not bent...even if i have to get my machine shop the guy I use for my business, to check it..:p.....

would putting a bolt thru one of chuck bolt holes be OK....i mean would it be more prudent to put it thru the hole used to access the front bearing cover..thus avoiding an possible damage to the chuck bolt holes

and yes as for pics I am getting around it to it
its one of these
http://image.cn.made-in-china.com/2f0j01mBUTrJPqHpbf/%E5%A4%9A%E5%8A%9F%E8%83%BD%E5%B7%A5%E5%85%B7%E6%9C%BA%28BB25-1L%29.jpg

[pipeclay]

Why not put a piece of material in your existing chuck,turn a centre on it and use that for turning between centres.

[eskimo]

Why not put a piece of material in your existing chuck,turn a centre on it and use that for turning between centres.

what would prevent (the material being turned) from slipping on the centre?

dont I need to use a dog/clamp or something

[pipeclay]

Yes,sorry I thought you would of known that.

[eskimo]

Yes,sorry I thought you would of known that.

thats why I am asking what I can do if I dont have a purpose made plate

[Stustoys]

Your pic link didn't work eskimo

You can't make a test bar until the lathe is set up correctly. Or do you mean you want to turn a bar that allows you to check it and adjust the set up of the lathe?

I'd use the hole closest to the center of the spindle so that there is less weight to unbalance things.

If you want to turn between centers you don't need a dog you can drill and tap a hole at 90deg to the axis of the bar. Put a bolt in that and use that to drive the bar. You still need another bolt in the plate to drive the bolt.

Stuart

[pipeclay]

Even with a purpose made plate you will still need something to drive the material.
Your purpose made plate wont do it by itself unless it has drive teeth or points.

[eskimo]

Your pic link didn't work eskimo



Yes it does ...now that I fixed it....:D




You can't make a test bar until the lathe is set up correctly. Or do you mean you want to turn a bar that allows you to check it and adjust the set up of the lathe?



err err ...you've lost me

[eskimo]

Even with a purpose made plate you will still need something to drive the material.
Your purpose made plate wont do it by itself unless it has drive teeth or points.

yes I gathered...but what to do

mine is something like this and plate setup as shown in this link...u may need to scroll down a little
mini-lathe Features (http://www.mini-lathe.com/Mini_lathe/Features/features.htm#Spindle)

Also noted that this site calls my lathe a 9x20
mine didnt come with the extra face plate...looks like its a bolt on job to the existing and uses the three chuck bolt holes
nor did I get those two big round things covering the centres and spanners....nor the two steadies...i got robbed.....:((

[Stustoys]

eskimo. I think you will find the holes you say are to get to the bearing are in fact holes for mounting a four jaws chuck. (assuming they are the same as the picture)
Stuart

[eskimo]

eskimo. I think you will find the holes you say are to get to the bearing are in fact holes for mounting a four jaws chuck. (assuming they are the same as the picture)
Stuart

My plate only had 3 bolt holes for the chuck

there is one extra which is not on the same dia which lines up with the screws holding the bearing cover ...

[Stustoys]

My plate only had 3 bolt holes for the chuck

there is one extra which is not on the same dia which lines up with the screws holding the bearing cover ...
Oh (I shouldnt assume hehe)
Is there enough room for a nut and washer between the plate and the bearing cover?
If there is, I'd make a pin that is a slip fit in the hole and tap the end what ever size it needs to be to suit. Closer to the center is better as it will be less out of balance.

Turning between centers just allows the work to be removed and replaced accurately. It wont make the lathe turn any more accurately than it is set up to turn.
To make a "test bar" you need to be able to turn parallel, the lathe needs to be set up accurately to do that.
http://www.rdgtools.co.uk/acatalog/Machine_Test_bars.html (http://www.rdgtools.co.uk/acatalog/Machine_Test_bars.html)

I'm not sure what you are trying to check anymore.

Stuart

[eskimo]

thanks Stuart
i want to tram the lathe...why... i want any faults that are produced on it to be mine and not the lathe's....no not really I will always find someone or something else to blame...its never my fault....just ask swmbo

I really want to see how accurate a product it can make so I wont set my sights too high

so what does one do first ...do you have to buy a test bar, or can it be made first on ones own lathe so that you can then tram your lathe?

Got a 4 jaw chuck yesterday, but thats useless till a get around to drilling 3, or is that 4 extra holes to accept it...

[Stustoys]

You don't need one of those test bar at all, they just make life a easier.
To test how accurate the set up is.
(guessing at sizes here)
Chuck a piece of 3/4 bar about 1 ft long, face and center drill the end. (do you have center drills?) Thicker bar would be better, just what ever you have around.
Slide the bar out about 10 inches and support the end with a live or dead(don't forget some oil) center.
Turn as much of the length as you can easily get to until you are cutting all the way around the bar.
Mark about an inch of bar each end then machine the rest of the bar down 1mm or so.
Now with a sharp tool and power feed take a very light cut off the two high sections.
Measure the Dia of the two sections, if they are the same size(or close enough for you) then you're done. If not you will have to find out why.
I did a terrible sketch if you are having trouble with my description.

Hope this helps.
Stuart

[pipeclay]

Never having seen or used 1 of these Lathes any or everything I say could be useless.

Firstly I would check to make sure the Headstock is securely mounted to the Bed.(Was the Lathe brand new when you got it,was it still covered in protective coatings.)

From what I have read the Headstock is located to the Bed by 3 cap screws and aligned by a Vee way.(Would be good if you can give them all the same torque.)

Check to see if there is any End float on your Spindle,also check to see if there is any Vertical movement in your Spindle.

If there is any excessive clearance you would have to eliminate that first.

Put your Dial on the Spindle plate after doing your checks and note amount of runout if any.

Hopefully you got an inspection sheet with the Lathe indicateing Tolerances ,if so as long as it falls in there range it should be fine.

Even if you havent got anything to go by ,as long as its not over the top keep going.

When you come to mount your 3 Jaw chuck it should be a reasonably tight fit on the Register on the Spindle plate,if its not you will have another thing to try and adjust.

Once the Chuck is mounted making sure that the 2 mateing surfaces are clean and the nuts Tightened evenly check the Runout on the Chuck Face and Body.( Compare to Spindle Plate).

If everything is still reasonable place a piece of Round bar Bright or Ground in your Chuck,a piece about 300mm long would be good(the largest diameter that you can fit).

Face and Centre Drill both ends.

For the 1st test I would have around 100/150mm out of the chuck,if its Bright bar it might not be running true dosent matter.If you are going to be useing HSS grind your tool accordingly,set a Shallow depth of cut( but so it is cutting the FULL diameter) fine feed and try around 300 RPM .If theres to much vibration try slowing the speed down,increasing the feed rate,changing the nose radious on your tool.(DONT change all these things at once but play with it untill you virtually have no vibration and a good finish).

Then measure the Diameter along its length and see if it is parallel or tapered.

If its not parallel but tapered you may have to adjust the location of the Headstock on the Bed,could possably be a dag on the Vee way or you may have to put shims against the Vee to get rid of the Taper.

If it is cutting within tollerance then bring the Tailstock up and take another Skim cut with the job supported by your centre,measure it again and check.

If its out this time remove the Bar and use another piece of material and machine a centre in your Chuck,you will either have to by a Drive Dog or make 1,it will get its drive from 1 of your Chuck jaws.

After you have machined the Centre place the Dog into position and do your test cut again.

By measureing the finished Diameter and noteing the sizes you will then know which way to adjust your Tailstock,check google but Im pretty sure if its Large at Tailstock it needs to move towards you and vice a versa (its one way or the other).

Use your Dial indicator against your Tailstock so you know how far you are moving it,generally move it half the error,and recut and check again.

If you can get any taper down to about .0005"/.001" thats pretty good.

[Stustoys]

I wouldn't mess with the headstock alignment until I was super sure that was the problem. Twist in the bed would show up the same.

[eskimo]

I did a terrible sketch if you are having trouble with my description.

Stuart

thats what I want to make...so back to how to drive a long bit of shaft to be able to turn it up

what would be best, considering the future..eg make a plate as it will be very handy in time to come...or just make a clamp and use a bolt thru the plate, and then toss it in the scrap bin after ....or is there other options

Pipeclay
Are you saying to fit the centre thru the chuck into the spindle taper?

Lathe Steady
does anyone have a good plan for a steady..i know they arent ..well shouldnt be that hard make.....but i am trying to use what I have around the shed.
I have a 200mm (od) dia x 170mm (id) x 45mm wide outer race of a roller bearing I was thinking of using, but would it be too hard to allow drilling 3 holes thru ....its as hard as...could I anneal small areas to allow the holes to be drilled thru for the bearing fingers?,...

would it ...a 200dia outer race be an over kill/under kill, look stupid..etc etc..
I will need to make a base for it to be bolted to so that it can sit on bed

[wannabe]

Lathe Steady
does anyone have a good plan for a steady..i know they arent ..well shouldnt be that hard make.....but i am trying to use what I have around the shed.

Have a look at this one http://www.woodworkforums.com/f189/things-you-have-made-your-hercus-83895/index2.html post No:27 with some pics back in post No:17. It's fully fabricated from what I had around the place.

[Stustoys]

thats what I want to make...so back to how to drive a long bit of shaft to be able to turn it up

You dont need to turn between centers to make this.


what would be best, considering the future..eg make a plate as it will be very handy in time to come...or just make a clamp and use a bolt thru the plate, and then toss it in the scrap bin after ....or is there other options

I'd leave making the plate until after you are sure your lathe is set up correctly. If the machine is way out it will effect the plate and you would have to machine it again later. I'd be tempted to make two plates, one as big as will fit on your lathe, that would be more easily done on another bigger lathe.
"Is there enough room for a nut and washer between the plate(back of the spindle) and the bearing cover?
If there is, I'd make a drive pin that is a slip fit in the hole and tap the end what ever size it needs to be to suit. Closer to the center is better as it will be less out of balance."
Here comes another crappy sketch.
You'd then need to drill and tap the bar so you can fit a bolt to reach the drive pin.


Lathe Steady
I'd go with something like wannabe's, it can be handy to be able to fit and remove the steady without having to move anything else.

Stuart

[eskimo]

You dont need to turn between centers to make this.

I'd leave making the plate until after you are sure your lathe is set up correctly. If the machine is way out it will effect the plate and you would have to machine it again later. I'd be tempted to make two plates, one as big as will fit on your lathe, that would be more easily done on another bigger lathe.
"Is there enough room for a nut and washer between the plate(back of the spindle) and the bearing cover?
If there is, I'd make a drive pin that is a slip fit in the hole and tap the end what ever size it needs to be to suit. Closer to the center is better as it will be less out of balance."
Here comes another crappy sketch.
You'd then need to drill and tap the bar so you can fit a bolt to reach the drive pin.


Lathe Steady
I'd go with something like wannabe's, it can be handy to be able to fit and remove the steady without having to move anything else.



Stuart

Gotcha!

Thanks Stuart & Pipeclay

ps ...Stuart your sketch's are beautiful...well great...they help a lot thanks!

[pipeclay]

Have you been able to sort your alignment out.

[eskimo]

Have you been able to sort your alignment out.

Not yet Pipeclay

Bathroom reno's have been soaking up my time...I also need some err lots of brownie points, so its best for my future that I do this.....

I then need to make a steady so that I can make a test bar of some 45mm scrap stainless fan shaft (old evap cooler) I have....I will need the steady later anyway and will be getting some 3/4 or 20, 25mm or whatever they have in stock square bar during the week...

I expect to be asking for more help and advice, so dont go away

[pipeclay]

If you can I would at the present time steer away from useing the Stainless,not because it wont do the job,but it can be a bugger to machine.
If possable I would suggest a bit of Centreless ground bar to use as your test piece.
I understand that the Stainless is free but the other will not be that expensive,20/25mm should be fine,even a bit of 1020 bright would be easier than the Stainless.

[Stustoys]

pipeclay. If he isn't holding it in a collet chuck and he will be machining it all over. What is the point of centerless ground bar?
Stuart

[pipeclay]

I forgot there was no 4 jaw,still that stainless will be a bugger.

[eskimo]

Pipeclay..its cheap stainless.....when I mean cheap its very low grade...not too sure what grade but it has surface rust on it.....like a tarnish so to speak

it worked fine on a little test I did when I made a top die for the bullet re-sizer...put it this way the end result was much better than the one I made out of mild steel....