Clarke cl300

[Acid-burnParticipant @acid-burn]

Hi all

Im new to this whole model engineering and i have a few questions. I have bought a second hand clark cl300 lathe. it works perfect (well it seems to with my limited knowledge) but i do have a few question

1) The forward, neutral, reverse lever on the back for the lead screw works, but i can only get forward and reverse, no matter how hard i try i cannot get a proper neutral engagment, is this a common issure with these machines and is there anything i can to about it (is there anything i can adjust) at the moment is i want to do some facing i take off the leadscrew plastic gear and lock the carrage using the half nuts to the now non rotating leadscrew

2) Whilst im on the subject i have noticed some side to side play in the leadsrcrew (about 1mm) is this normal? there is no play up or down (i think that is a bad thing if there is up and down play, is that worn bushes?)

3)I have been looking at some easy mods for the lathe (thank you mikes workshop) are there any other simple mods a new girl can do?

4) Will the leadsrew fit through the hole in the head to be centre drilled for a handle extension?

Well thats all for now, like i say im a new girl to all this so im hoping for some answers

Thanks

Leanne

[Acid-burnParticipant @acid-burn]

A few questions

[john swift 1Participant @johnswift1]

Hi Leanne ,

on my lathe , I had to move the position of the neutral de-tent , by carefully drilling at an angle so the existing dimple drifted by about 0.5mm from its original position .

the die-cast drive belt cover is only about 2.5 mm thick ,so the revised de tent can't be drilled too deep !

the lead screw will fit through the spindle , the lead screw is 16 mm diameter and the spindle bore about 20 mm

with the far end of the lead screw unsupported , don't us too high a speed when drilling the other end , to attach the handle

the greatest improvement I've made is to replace the spindle bearings with taper roller bearings from Arc Euro Trade

see arceurotrade.co.uk/projects.aspx

unless you have another lathe , just ensure your make the new longer spacers before , you  remove the spindle ! ( the centre of the roller bearings are off set by about 1.25 mm

the  new roller bearings and new gibs solved my problems with parting off and improved the finish (both being sold as spares for the C3 lathe

note- the CL300M is a C2 lathe and the motor and speed control is not the same as the one used on the slightly larger C3 lathe

John

 PS        I'll take a picture of the three detents on my lathe

the neutral position  is not half way between the others , its closer to the reverse position

Edited By john swift 1 on 11/07/2012 15:33:38

[john swift 1Participant @johnswift1]

missing pictures

the neutral detent is about 3.6 mm from the reverse detent and about 4.9 mm from the forward detent

PS –  I forgot about the lead screw

to reduce  the sideways  play in the lead screw and  avoid enlarging the mounting holes in the lead screw bearings ,  

I just  added a brass washer onto  the right hand end of the lead screw

    John

 

Edited By john swift 1 on 11/07/2012 17:16:16

[Michael Cox 1Participant @michaelcox1]

Hi Leanne,

I think John has covered most of your points but with regard to the side to side play on the leadscrew you have two options.

1. Loosen the bearing blocks at either end of the leadscrew and see if you can push them closer together to remove the slack. You will have to re-align the bearnig blocks to ensure that the leadscrew can still rotate easily and that on closing the half nut the leadscrew does not move. If there is not sufficient movement in the bearing block to take up the play in the leadscrew then you could elongate the holes so that then can move horizontally to take up the play.

2. The other method of taking up the play is simply to make a washer the correct thickness to take up the play. This is the easiest solution if there is a lot of play.

I think there are instructions for aligning the leadscrew in the ArcEuro guide.

Mike

[blowlampParticipant @blowlamp]

Once the plastic cover for the change wheels is removed, you can see two securing bolts (situated top-left and bottom-right) for the aluminium casting that all the mechanism mounts on to.

Loosen these bolts with the lever in the neutral position and see if you can obtain a satisfactory clearance that will allow the tumbler assembly to work as intended when moved into each position.

I had the same problem with my lathe and managed to sort it out without too much trouble by making this adjustment, although it was a bit fiddly.

Martin.

[Acid-burnParticipant @acid-burn]

Hi all thanks for the advice

Martin – I have tried today to adjust that back plate and no matter what i did i couldnt get both of the gears clear. they just seem to be so closely aligned

Mike and John – thanks for the advise, i will try the spacer idea first to try and take up the slight movement. John i have to say that the taper bearing mod sounds good, but also a bit scary for me due to the need for pressing to be done and spacers making for the new bearing (i dont mind having a go at making a small spacer for the leadscrew but im not confident in my newly found skills to make realy really really (you get the idea) accurate parts yet (and in a part of the lathe that is so vital) However you did mention somthing about solving the parting off issue? whats that? (i know about parting off but is there an issue with these machines?)

Thank you all again

Leanne

Oh by the way im making a little vertical steam engine im going to call her ivor lol

[Sub MandrelParticipant @submandrel]

It should be possible to move the tailstock leadscrew bearing mount enough to take up any play.

The leadscrew will fit through the mandrel bore.

Take the gear cover off. Forward-neutral-reverse should each have separate detents, with it on the middle one the tumbler gears (two gears attached to the lever) should be clear of the bull gear wheel. in forward and reverse one or the other of the gears is engaged.

Good luck!

Neil

[blowlampParticipant @blowlamp]

Leanne.

I can't remember for sure, but I may have elongated the slots with a small round file to get enough clearance for the gears.

As for the end float of the leadscrew, I just left it alone with ~ 1mm of play because it's inconsequential to the function. Like you, I engage the clasp nuts when facing, but as long as I bias the saddle to remove the play it all works OK and the same thing applies whilst screw cutting.

Martin.

[Acid-burnParticipant @acid-burn]

Hi Martin

Yes i have been doing that, everytime i need to face anything i remove the plastic leadscrew gear (i havnt sorted that neutral lever yet) i then move the saddle across to the work piece and lock the halfnuts, i then turn the sadle level just a mm and the whole leadscrew shifts towards the tail (looking at it again its probably not even 1mm) then im ok for facing. its a bit annoying really as the lathe is in pretty good nick, (i think it might have been in a school at some point as it has a really old electrial safety sticker on it from way back before i was born lol) every other tolerance on the lathe i tight with no slop.

Im going to be ordering one of the Sieg X1L milling machines from Arc Euro soon (when i have saved some more money) Do there prices stay steady does anyone know?

Thanks Again

Leanne x

[Michael Cox 1Participant @michaelcox1]

Hi Leanne,

The best way to cope with facing is to make a carriage lock for the lathe. Look at the gadgetbuilder website (http://www.gadgetbuilder.com) for a simple solution. I have used this arrangement but I modified the lever so that the tailstock can come right up to the saddle, see **LINK**

I have the Sieg X1L and I am very pleased with it. The prices of machines at the moment are rising all the time because the pound is weakening against the Chinese Yuan. This is a side effect of quantitative easing.

Mike

[AndyfParticipant @andyf]

Hi Leanne,

I do know of someone whose leadscrew gear quadrant (the plate to which the shafts of the two gears attached) was badly made, with the gears so close that neutral couldn't be achieved. When changing, one gear started going into mesh before the other was fully disengaged. I had bought a quadrant LINK from Little Machine Shop in the US for a failed project, so didn't need it and passed it on. That solved his problem, which may be the same as yours.

Clarke branded lathes are sold by Machine Mart in the UK, and they boast a spares department, but that item won't often be requested so they might have to order it. LMS carries a pretty comprehensive stock of spares, and the shipping charges are relatively reasonable. They were very prompt with my order; it took about 9 days to arrive.

Andy

[john swift 1Participant @johnswift1]

Hi Leanne ,

a few years ago my first attempt at parting off on my 12 year old CL300M was a little exciting !

 

small inexpensive lathes like the CL300M are made with the minimum of cast iron needed

the bed is more flexible than heavier (and more expensive) machines of the same capacity

the resulting unwanted movement of the tools, when combined with the effect of ill fitting gibs

inadequate spindle bearings makes parting off a problem

 

on my first attempt , the tool deflected downwards as the work piece climbed onto the top of the parting off tool

that's was with the parting off  tool as close as I dare to the chuck and the minimum unsupported length

the main problem being  the original gibs , both under size and bent out of shape – new gibs fixed the problem

the chuck proved to be OK and importantly the jaws undamaged

but some play and roughness was detected in the spindle bearing – some thing that I would of left until later , if I had not needed to replace the plastic double gear on the main spindle ( part of the gear split after the parting tool jammed for the 4 or 5 time)

the parting off tools that are supplied with the lathe appear to be too wide

when I reground the tool , I made it 2 mm wide instead of 3 mm

the thinner tool reduces the bending forces on the lathe and reduces the load on the motor

 

one mode still on my to do list , that you may want to look at is the carriage lock :–

**LINK**

John

 

 

Edited By john swift 1 on 11/07/2012 23:44:51

[Michael Cox 1Participant @michaelcox1]

Hi John,

The link that you posted to the Toolsandmods website actually describes a carriage lock for a Real Bull minilathe. This has a different carriage to the Seig version of the minilathe which has a H shaped carriage. The toolsandmods version of the carriage lock is not therefore appropriate for the Seig (eg Clarke) minilathe that Leanne has.

Kind regards

Mike

[john swift 1Participant @johnswift1]

Hi Mike ,

while its true the lathe shown is different to the CL300M that Leanne and I have

the carrage lock idea is still good ,

it just needs a metal bridging piece fastening in place using the existing tapped holes normally used to attach the travelling steady

that way the mod is totally reversable and the lathe can be returned to its original state

I guess , it all depends on if your looking for ideas or detailed plans

John

[Michael Cox 1Participant @michaelcox1]

Hi John,

I too have the CL300m lathe and I totally agree that a carriage lock is a good idea. Prior to your post I had already given a link to the carriage lock on the gadgetbuilder site which is for the Seig minilathe. I just thought it was a little confusing for Leanne to direct her to the carriage lock for the RB minilathe.

Mike

[Acid-burnParticipant @acid-burn]

Ok

So now im really confused lol. so the carrage lock in the link wont fit our machine? (Why didnt they just come with a carrage lock lol)

At the moment im currently halfway through boring the cylinder for ivor, she is sat in the four jaw chuck waiting for a 13mm MT2 drill chuck to arrive from Fleebay

Leanne x

[Michael Cox 1Participant @michaelcox1]

Leanne,

The gadgetbuilder link in my post about 7 back give information on a carriage lock for the Seig 7x 12 minilathe (i.e. the Clark 300M).

Mike

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