Myford quick change gearbox questions

[Ockert LombardParticipant @ockertlombard60769]

[Ockert LombardParticipant @ockertlombard60769]

Can anybody please help me to answer the following questions regarding the mounting of a Myford quick-change gearbox to a Super 7 lathe.

Firstly, I would like to know if anybody has an idea when my gearbox was manufactured. Its number is QC109572. (It is still brand new, in the box and has never been used.)

My Super 7 was manufactured in 1975 (its number is SK124399M) which is fitted with a power cross traverse. I would like to know if there are any special precautions that I have to take when mounting the gearbox or can I just follow the manual.

I have downloaded a manual from the internet and also have one that came with the gearbox. There seems to be slight differences between the two. In the one received with the gearbox, they explain a procedure "Preparing the leadscrew (re-using early leadscrews)" whereby one needs to reduce the leadscrew diameter. The one from the internet makes no mention of this. Can you please advize on this.

Any advice and tips will be appreciated.

Thanks

Ockert

[LambtonParticipant @lambton]

Ockert,

Last year I fitted a new unused QC gearbox to my Super 7 fitted with power cross feed. I followed the instructions that came with the box and found no problems. The worst part was shortening the lead screw as this was the only step that was not reversible – a bit like having a sex change operation!.

My gear box is one of the last produced by Myford and the instructions do not mention anything about preparing the lead screw just a bit about shortening it.

What I suggest you do is take out the lead screw (an easy job) and offer up it up to the gearbox and the new lead screw gear No. 168 and check that it fits the diameters properly. If it does then all you probably need to do is shorten it as per the instruction. Please note the lead screw will already have the seating for the woodruff key needed to drive gear No 168.

There are several sets of detailed instructions steps depending on which model lathe you have. I photocopied the relevant pages and after very carefully reading through several times I blacked out the words that I did not need to avoid confusion once fitted had started.

The whole job went very well and I was immediately pleased with the results.

There is some confusion in my instructions concerning lubrication stating in the front of the manual to use Esso Febis K68 and on page 15 to use SAE 30 oil. I do not think it matters either way as long as the correct oil level is maintained as the gearbox never gets hot and is only ever lightly loaded. The K68 is more sticky an probably clings to the gears better when the box is idle however within seconds of being turned on the oil is splashed over all the moving parts.

I hope this is of some help

Eric

[Ockert LombardParticipant @ockertlombard60769]

Hallo Eric

Thank you very much for the advice. I needed the confirmation to start my Super 7's sex change! I will let you know how things went.

Regards

Ockert

[pierre ehly 2Participant @pierreehly2]

Hi,

The ML7 was built with an 5/8" LS until Apr73 (sn:K111727) and the S7 use a 3/4" LS.

Both machine using the same Gbx, an adaptation muss be available.

pm

[Ockert LombardParticipant @ockertlombard60769]

I managed to fit the gearbox to my Super 7. Everything went fine. I just had to modify the changewheel guard to fit. It meant some cutting and filing but now it is fitting fine. I just need to top up the gearbox with oil and then I am ready to go!

Thanks for the help.

Ockert

[Pete HillParticipant @petehill80830]

Posted by Ockert Lombard on 10/01/2014 07:43:01:

I just had to modify the changewheel guard to fit. It meant some cutting and filing but now it is fitting fine. I just need to top up the gearbox with oil and then I am ready to go!

Thanks for the help.

Ockert

Hi Ockert

I have just finsihed fitting a QC gearbox to my S7 , I have found the guard is not closing correctly due in part to the lever that locks the spindle and a slight issue with the top section of the guard catching the bearing housing. Can you confirm this is a similar issue that you had? I don't want to start removing metal to find I can shim it out or some clever fix, but it does not look like it from what I can see.

Thanks Pete

[Author]

Posts