[wildwestpat]

These chucks are held on to the spindle by short bolts or nuts and a captive stud which is fixed into the back of the chuck. Having removed those nuts / bolts the chuck should just pull off in the direction of the tail stock. Little machine shop has a good picture of the spindle here Spindle, Mini Lathe 7x14 - LittleMachineShop.com There are two hole patterns - four at 90 degrees used on the four jaw chucks and three at 120 degrees for the three jaw. The holes are clearance on the studs / bolts. The chuck is registered on the projecting smaller diameter part of the flange integral to the spindle. This projecting flange meshes with a similar recess that is found in the back of the chuck body when you have removed it.

Is the lathe new? If it is contact the supplier as it has either been abused or has rust or dirt trapped between the mating diameters. IMHO this indicates that the machine should be replaced. Do not accept a replacement spindle and chuck unless you are confident you can dismantle and reassemble the beast. Not difficult and here is a link to some instructions from Arceuro. Although the instructions apply to the Seig C3 the method is similar although the castings are slightly different. Arc Euro Trade - C3 Mini Lathe Bearing Change

Hope this helps. By the way if you leave the electronic trip set as supplied it will stop the motor before the plastic gears fail - don't ask me why I am sure but I bought a set along with the taper roller bearings just in case! However the lathe performs well so I am leaving it alone. Guess having the bits in the draw under the lathe is like buying insurance or carrying an rain coat in summer.

Can I ask why you are looking to reset the tail stock as there are several factors to take into account if accuracy is you bag. The centre of the tail stock has to be true for all positions along the bed. This is checked by turning between centres and there is a good write up on how to do this on the web. BUT and it is a very big but some of the correction may involve the head stock as the bed reference 'vee' + headstock spindle + tail stock spindle alignment all have an influence on the accuracy of your machine. If you have just moved the tailstock on the adjusting screws getting it back to the start position is easy. Just do as Dano has suggested or simply put a bit of ground round stock in the drill chuck mounted in the tail stock bring the protruding ground rod up to the headstock chuck with its jaws wide open. Then simply close the jaws a bit at a time testing with a slip of thin paper that the grip is equal. Most likely it will require adjusting but as you get near to the correct setting just rock the chuck back an forward using the chuck key making sure the lathe cannot be powered. Sounds complicated but is very quick to do and is a good use for a broken drill. Also do not forget the jaws on the chuck are designed to be tightened in a set order. Get into the habit of nipping the work with jaw number one and then tightening the others in numeric order. Some chucks are just marked with a punched dot and not numbers - the jaws are also similarly numbered.

Regards - Pat

[earthman]

Thanks guys for all the help/replies.

So there's a captive nut on the chuck hey, that would explain why it was still rock solid, I didn't even notice another hole at the back of the chuck when removing those 3 nuts, I'm normally pretty good with things like that.
Could it be behind one of the 3 jaws? maybe I'd have to remove the jaws to find it?

I bought the machine new at the beginning of this year, I followed the instructions in one link on how to check that the motor/drive belt is set correctly, I didn't strip the machine down fully, just enough to satisfy myself that it's (hopefully) OK.

I've not actually used the machine much at all, it is my first lathe/go at machining period so I'm not even fully up on all the terminology that you guys know/use.

All I've done so far is turn down a small section of bar and drilled holes in the end. The hole didn't look central to me hence why I've been messing around with tailstock adjustment.

How do you guys get a centre punch mark dead in the centre in the first place? It could have been my fault, I've never found using a centre punch/marking the centre of a bar whilst in a vice easy, the drill bit just followed maybe??

The last hole I done looked a lot better to me (see my previous picture).

Is it OK to mark the centre of a piece of bar via using a dead centre in the tailstock, sliding it gently along the bed and tapping the bar whilst it's clamped in the chuck??

I'll try to do what's been suggested so far in the next couple of days, it's hard to find lathe time at the moment, I'll keep you all posted.

[wildwestpat]

There are no hidden fixings. The chuck is held in place on the register of the head stock spindle by thee fixings which will either be nuts and washers or short bolts. (four fixings if a four jaw) When these are undone the chuck simply pulls off. Do not remove the jaws with out first ensuring they are marked with their corresponding slots. The jaws have to be replaced in their correct slot as the chuck key is rotated starting with the jaw / slot marked one. If you mess up the sequence the jaws in a self centering chuck will be way off center by many mm.

You should use a center drill in the tail stock chuck assuming the surface is not too rough. The center drill is short and very stubby and makes a small hole with a larger tapered counter sink that matches the tail stock center. Keep the tail stock clamped to the bed and advance the center drill using the hand wheel slowly and use a drop of oil if using steel. If you are in need of basic information get the workshop practice series number 43 would be a good place to start.

There is no need to strip the machine down as it is supplied in a condition to work as taken out of the box unlike some others which need extensive cleaning.

Regards - Pat

[earthman]

Spent some time on the lathe, turned a piece of bar and used a Stanley knife blade, that's all I had to hand at the time, looks like the tailstock is a tad low to me? I'm thinking that maybe I could shim it up with a pair of feeler blades, not ideal I know but I can't see another easy/cheap option.

[IMG][/IMG]

This is the first time I've even attempted to cut at an angle other than 90 degrees, couldn't work out how to adjust the compound at first, not very convenient those two bolts are they? Is that the same for all lathes then?

[IMG][/IMG]

I will look into buying that book, ideally I would have liked to have gone to an evening course, sadly I can't find any college/school any where near me that offers such a course.

Clips on Youtube are handy and the site below.

Lessons on The Lathe « Start Model Engineering

[wildwestpat]

The test you have done with the blade indicates that the two centers are reasonably close in alignment and certainly close enough for your first ventures into the delights of turning.

Yes the compound operates in a less than ergonomic fashion but you will find that reaching over to the feed wheel soon becomes easy and turning the feed in a nice slow uniform manner will be natural. However the tool should be mounted on the other side of the four way tool post to reduce the over hang.

Here is a link to a series of videos by MIT as part of their degree courses on robotics - I think it is for students venturing into their workshop for the first time with the need to cut parts for their robotics course work. http://techtv.mit.edu/genres/24-how-...machine-shop-1

Get started and enjoy - Regards - Pat

[earthman]

However the tool should be mounted on the other side of the four way tool post to reduce the over hang.

Do you mean the side that's parallel to where the bit is now? If I mounted it in there then wouldn't I have had a clearance issue with the corner of the tool post hitting the chuck? I take it that I'm meant to have the work piece sticking out as little as possible.

I'm not sure I follow you about the 'over hang', do you mean that the tool post should remain more in the centre of the compound throughout the entire cutting procedure?

I found it difficult to set up, juggling with having enough room to turn the compound knob without hitting the splash back, making sure nothing was going to collide with the chuck.

Thanks for the link to that first clip, just what I need to watch.

[wildwestpat]

With any machine it is good practice to have the maximum support possible for both the cutting tool and the piece of material being worked. In the last picture you took it the tool could be better supported by:-
1. Take the cross slide back towards you so that the slide is almost fully retracted - you may need to drive in when you have set up the compound slide to the angle at which the cut is to be made but this is step 4
2. Run the compound away from the head stock to expose the two locking screws - slacken the screws a little anf adjust the angle of the compound slide as required - re lock the two screws and re check the angle.
3. Now run the compound back towards you so that the slide is fully engaged - this will provide maximum rigidity - another way of expressing this is that the three gib adjustment screws should be over the mating part of the slide and not operating against free air.
4. Place the tool in the position that gives minimum over hang and is nearest to the work piece. In most cases this will be the tool position that is to the right when the compound is set to zero degrees off set. This also means that the compound is operating with the slide supported by the dove tail slide over a much longer length and gives more room between the splash guard and the hand wheel. Also adjust the amount the tool over hangs the tool post slots if necessary to ensure the chuck is clear of every thing in all positions of the compound slide. Adjust the position of the saddle ( big wheel) and the cross slide to apply the cut and also ensure there is working clearance on the chuck. You might find that the work piece has to be extended.

Going back to you drilled hole - IMHO what you probably did was to chuck that bit of rod and then proceeded to drill the hole with an ordinary twist drill. This is not good practice as twist drills have a problem removing material in the center of the hole because of the way they are sharpened. This causes the drill to slide about causing the hole to wander off as the drill has very little metal due to the depth of those twists. Use a center drill to start the hole then increase the depth using a small twist drill of size similar but a little bigger than the parallel hole made with the center drill then open up to the required size in stages. Please also note that when drilling with the tail stock the chucked drill should be retracted to say the zero marking on its quill and the quill lock adjusted so that the drill can just be advanced using the hand wheel. Now push the tail stock carefully down the bed so that it is near where the hole is to be made and firmly clamp it to the bed so that you are ready to make the hole - center drill first then open up to the required size. It is best to face off the end of the work before center drilling.

Hope this helps - Regards - Pat

[earthman]

Thanks again for all the tips, I understand, the 3 gib screws being in the air makes that point crystal clear, I should have noticed/realised that.

You are right about the drill hole, I just centre punched the bar and used a 3mm drill bit to start with. I've since bought a load of bits for my lathe, centre drills, dial gauge and a quick change tool post are amongst the items I got.

I always assumed that the cutting bit would go in the slot that's closest to the chuck, I guess that most pictures I've seen show that. If I twist the post around and fit the bit in the other way so it's on the right hand side, a piece of bar would have to stick out of the chuck by 3" or more, notice that the tool post clamp is sticking out towards the chuck too.

I'm having problems in general with that tool post locking lever, when tightening/losing it's fouling the height adjustment screw of the cutting bit. Am I suppose to have/use another washer/spacer under it? Or am I just meant to keep unscrewing/removing it's 'arm' to avoid hitting that adjustment screw?? Or am I meant to slide off the tool holder first??

[IMG][/IMG]

[IMG][/IMG]

[handlewanker]

This problem you have is like a correspondence course for brain surgery by someone who neither reads nor understands English, so having regards for my blood pressure I will refrain from giving detailed and very boring explanations on how to plug the lathe into the wall socket and then switch the damm thing on.

I would strongly recomend having someone by your side before you lose a finger or two or poke your eye out.......grrrrrr!....the advice with the razor blade had me frothing at the gills, so I'm off to make a cup of tea to calm down a bit.
Ian.

[earthman]

Er, steady on Handlewanker, folk are only trying to help me.

I've learnt to using many different machines over the years, not lost anything yet, always think about the H&S aspect first.

[WaveDude]

Ideally the handle will point towards the "south-east/lower-right/4-5 o-clock" corner or directly towards you when tight. You have a lathe. Tighten up the tool post where you want it then unscrew the handle that gets in the way. Then turn up a small washer to put under the tool-post "nut" and size it so that the nut tightens up "earlier" and is no longer in the way when tight. Or you could turn off a bit off the bottom of the "nut" so that it will tighten up a bit "more" so that it ends up out of the way.

[handlewanker]

Hi, good advice re- the handle position....to get it precise find out the pitch of the screw holding the handle on and either add 1/2 of the pitch for the washer thickness.....it's easier to make a washer slightly thicker than a thin one, so if the pitch is most likely metric and about 1mm pitch (whatever), just make a washer 2-1/2mm thick, which will make the handle face 180 degrees back and to the right side.

Sorry I bit your ear Earthman, but anyone getting a piece of machinery and then attempting to learn the hard way by hack and bash gets my goat.

BTW, if you've slackened the bolts off holding the chuck to the backplate, (at least one turn), then it's sticking in the register spigot between the chuck back face and the backplate front face........give it a few GENTLE taps on the top of the chuck body with a block of alluminium, turning the chuck as you do it, to loosen it....then remove the screws once the chuck is loosened........be carefull and put a piece of wood board on the bed to stop any impact craters from the chuck.

When I fit 3 jaw chucks to backplates I always, as in always ever, make the spigot at least .002" slack to allow for any subsequent run out that develops with 3 jaw chuck useage and wear and tear.....it allows me to get the chuck to run true no matter what.

NEVER use excessive force to hold a job in a 3 jaw chuck......use a 4 jaw for extra holding power........the 3 jaw can be considered a poor man's variable collet chuck for all intents and purposes.....an essay is needed to explain why.

I seem to see a carbide turning tool in one of the photos.......avoid them for general purpose turning as they chip and blunt too much with inexperienced handling, and if you don't have a diamond lap on your tool grinder you won't get any results worth noting.....use High Speed Steel and learn how to sharpen the required nose forms for all your turning needs.
Ian.

[wildwestpat]

Suggest rather than make up a washer use a thrust race these are available from ArcEuro Trade in the UK and you will find a good description on their web site of these lathes.

Here is the link to their web page with the 10x24x4 needle roller race. You can adjust the height by omitting the lower flat race way to get that locking lever out of the way. Do explore this site as there are a lot of links and ideas that should help you including that book! http://www.arceurotrade.co.uk/Catalo...er-C3-Upgrades

As a general point these lathes are not suitable for heavy duty machining so you should not be thinking of changing the three jaw chuck until you have mastered the basics. The motor will trip out long before the chuck loses grip provided you have tightened the jaws in rotation.

Regards - Pat

[handlewanker]

Hmmmm, I think I did mention that you need to know the pitch of the bolt holding the toolpost down in order to move the handle a half turn or so.........just using a ball or needle roller race serves no purpose unless it's thickness is a specific half pitch of the bolt.

Incidently, using a race of any description is not adviseable.....the locking handle requires there to be friction between the 4 way or quick change tool post body and the locking handle bottom in order to ensure that when the handle is tightened it stays there......no friction and it will just turn back with the slightest vibration.

With regards to the chuck....you DO need to remove it when necessary to fit a 4 jaw chuck or face plate...but only when the occasion (job type) occurs....it's horses for courses, again requiring another essay to explain why.

There appears to be a misunderstanding in refitting jaws to a 3 jaw chuck, both for the normal or smaller diam gripping capacity and the reverse jaws for larger diams.

First of all both types of jaws can fit in ANY slot in the chuck, but only in a specific order, starting with jaw marked no1 inserted in one slot (any slot) and working around the chuck face in a clockwise manner.

That means you first insert jaw marked no1 in ANY SLOT and rotate the scroll with the chuck key as if you were tightening the chuck, (chuck key turning in a clockwise direction), while lightly pressing the jaw in...but only for a bit until the thread on the scroll engages with the jaw back grooves, then insert jaw no2 in the next slot around (clockwise) and rotate the scroll a bit more to grip it, next insert jaw no3 in the last slot and rotate the scroll again to engage it.

Correctly fitted, the 3 jaws come to the centre simultaneosly.

There is also another misnomer....tightening of the 3 jaw chuck......it is not necessary to apply force to all 3 jaws seperately......the scroll does that automatically and no purpose is served in applying more force to all 3 tightening slots.

During normal chuck useage, the key is inserted in the first hole that happens to come to the top, and that is used to release or tighten the chuck.....not in any specific hole for that purpose, they all do the same job.

If the chuck shows any holding diffence in a tightening sequence then it's worn out and the scroll is kaput.

The three tightening slots are for the convenience of not having to search for the next slot......you actually only really need to have one slot to tighten the chuck, but that's a tedious search for that hole when the chuck stops.....having three slots maintains the balance too.

Do I need to say that you MUST NOT LEAVE THE CHUCK KEY IN THE CHUCK WHEN NOT USING IT?.....some chuck keys are fitted with a spring to eject it, so preventing you from leaving it in the chuck.
Ian.

[earthman]

Sorry I bit your ear Earthman, but anyone getting a piece of machinery and then attempting to learn the hard way by hack and bash gets my goat.

No worries, apology accepted.

Like I've said, I'd love to go on a course really, sadly no school/college any where near me does a evening/night course.

What else is one suppose to do? Apart from clips on Youtube, books and the fine folk on here.

I did get the chuck off in the end, very gently used a pry bar between the casing and end of each stud, it moved straight away.

The turning tool in the picture is one from a set below.

Amadeal Ltd. Lathe Tools - Brazed on Carbide set

[wildwestpat]

Good so you are making progress. Just a note of caution about carbide edge cutting tools. 1. They do not like intermittent cutting as in turning square or hexagonal stock to a round. If you want to do this use HSS or take it very gently high speed very light cuts. 2. Carbide is very sensitize to sudden temperature changes so either machine dry or use a continuous stream of coolant. 3. Carbide is the province of high speed and high feed rates (feed = depth of cut and traverse together). 4. Needs diamond laps or wheels to sharpen properly hence you being advised to learn on HSS.

I personally use carbide insert tooling and only revert to HSS for special form tools. If you venture into insert tooling avoid any where you do not understand the long number or are missing the long number as this refers to the type of material they are designed to cut as well as the expected finish and feed rate.

Fully appreciate about the lack of courses as I am a volunteer at a centre that teaches basic workshop skills to non academic kids as this is no longer taught in schools. It is great to see kids take to machining and find they are good at it.

Keep going - Regards - Pat

[handlewanker]

Hi, you have my deepest sympathy re the lack of night school courses.......shock horror, a pry bar on a lathe!!!!!....now I'm going to need another bucket of tea.

BTW, at all costs avoid buying what is commonly referred to as "throw away Tungsten Carbide tips" or indexable tool holders with Tungsten Carbide tip inserts......they will cost you a fortune and will not work in your case.......they will cut metal, but so will a carving knife designed, to cut bread, cut the Xmas turkey.

Indexable Carbide tips are designed for CNC useage to get the maximum repeatability from tool set-ups and tip replacements.

They can be used when you have to cut cast iron or bronze, but again at all costs try to avoid anything to do with cast iron.....it will leave you and the lathe in a mess from the graphite in the material.

You will need a bench grinder to make and sharpen HSS tool bits, and as your "tuition" here progresses you'll get to know how to make and sharpen your own tools at next to nothing cost.

I'm getting the cold shivers thinking you might get ambitious and attempt to part off something.....wear a hard hat and safety glasses and keep your fingers crossed.....you'll need all the help you can get.
Ian.

[earthman]

The pry bar I used was a very short one, could have been a small screwdriver, went in very gently, the studs started to move straight away so no drama/worries there.

Yes I do have a bench grinder already, I thought that the tool holders with the inserts were the best ones to go for? However I were only offered the set I've got at the moment, I had bought the machine that day too so money were tight anyway.

I will want to go the HSS bit route once I've found out how to make them.

I will enjoy using the quick change tool post for sure, haven't tried to part anything off yet, I'm not entirely sure which cutting tool out of my set I'm meant to use for that.

[wildwestpat]

Here is a good illustrated guide to the angles required http://www.discoverlivesteam.com/books/Sharpening.pdf
Suggest you print this out and keep it by your grinder. I would suggest that you also get a small diamond lap (1000grit and the credit card size is fine as you will only be giving one or two strokes to the tools edge) to just touch up the cutting edge and to provide the very small radius on the tip of the tool. The use of a small radius gives a more robust edge to the tool. You also need to dip the embryo cutting tool in water to keep it cool as you shape it. The steel must remain uncoloured through out the grinding and in use or the temper will be drawn and the dge will not stand up to use.

Regards - Pat

[earthman]

Thanks for the pdf, that will be most useful.

I take it that there's more than one type of cutting tool to make, which ones would you say are more important/a beginner is likely to want?