Thread: Hercus AR saddle re-assembly

Hello Ken,
The clutch on my Hercus Craftsman is in need of a good service but I am unsure how to remove the apron.
Can you confirm the method and add any further information for a poor Apprentice

1. Remove 2 screws holding Saddle to Apron.
2. Remove Saddle by sliding to end of bed ways.
3. Remove Leadscrew rear end bearing.
4. Slide Apron along Leadscrew to remove.

What have I missed and what agonies are ahead.

Thanks
Colin

Col,

What you describe sounds ok to me. It's a fairly straight forward job, take care not to bend the lead screw by supporting the free end. Would be interested to know what condition you find the clutch parts in, after dis-assembly.

Ken

Originally Posted by neksmerj

Col,

What you describe sounds ok to me. It's a fairly straight forward job, take care not to bend the lead screw by supporting the free end. Would be interested to know what condition you find the clutch parts in, after dis-assembly.

Ken

Thanks for info regarding the removal and supporting the free end of the leadscrew.I used V blocks and packing and slid them along towards the free end as I removed the apron.
As you stated, a fairly simple job.
The clutch on my machine required over one turn to engage and sometimes slipped under cut hence the need to remove and inspect.

Photo 1 shows the debris that has probably collected over the 40 years.
Photo 2 after cleaning with kerosene.
The feel of the clutch was much different after the cleaning that I decided to re-assemble without taking the clutch apart (it is a simple job as you said).

I took a few test cuts and no apparent problems.
Thanks again
Col

Just out of curiosity. I notice that some half nuts are painted blue, and some are painted green. Is this a color code? My (otherwise green) 260 is metric and has blue half nuts and blue cross slide nuts. Would this mean blue = metric and green = imperial? Would make sense. Chris

youve got it chris metric half nuts and spindle nuts are painted blue
john

Col et al, Afternoon...

Ta for posting those pics, pretty much answers the my query way the thread cutting lever on my x TAFE lathe will only engage if forced.

As I have only ever made something on a lathe once in my life (and that was in 1970), I am somewhat knowledge deficient of things to do with lathes, not least of which is the terminology...but will endeavor to release the apron assembly after figuring out just how I release the lead screw.

Cheers, Dick

Originally Posted by greencan

Col et al, Afternoon...

Ta for posting those pics, pretty much answers the my query way the thread cutting lever on my x TAFE lathe will only engage if forced.

As I have only ever made something on a lathe once in my life (and that was in 1970), I am somewhat knowledge deficient of things to do with lathes, not least of which is the terminology...but will endeavor to release the apron assembly after figuring out just how I release the lead screw.

Cheers, Dick

Hello Dick,
We are in the same boat. I last put hands on a lathe in the early 50's but was in the Cemented Carbide industry since 61.
The removal of the apron was a ten minute job after the help I got in this thread.

The lead screw is released by removing the bearing at the tailstock end. Two screws pass through the bedways and retain it.
Wind the saddle to the tailstock end and support the leadscrew to prevent it sagging and bending.
Remove the two saddle clamps, one at the rear of the cross slide (two hex screws) and
the saddle clamp (a square head screw above the half nut lever).
Lift the saddle upwards from the front and move to a safe position,
Release the two screws holding the tail end bearing of the leadscrew, supporting the apron in the process.Slide off the bearing off and slide the apron toward the tail end to release it.Just make sure the half nuts are open.

Then inspect the apron..hope it is in a better state than mine.

Regards
Col

Evenin' Col et al...

Thank you for that, snap...I've recently retired after 30 years as a Paramedic so if I refer to specific components as 'thingies' you'll know what I mean then.

It's been an arvo of bonuses for me as firstly I established that my wireless internet connection works well in my shed so I was able to use an old laptop and open this thread and re-read it and I was able to remove the apron like you (and others said)...thank you

Although I didn't quite have the same amount of scrap metal encased within, simply cleaning all the innards with kero didn't free up the thread cutting engaging lever (I'm sure this has a more appropriate name). Anyway, I was able to dismantle it without any dramas and found that it wasn't waste that was causing it to jam up, but (bear with me on terminology), but a small rod of approx 1.1/4 x 3/16 that I think is meant to prevent the thread cutting lever to be engaged simultaneously with the feed screw had had it's ends quite badly burred over.

Some careful filing and buffing fixed that, and it all went back together without difficulties, and presto the screw lever engages and disengaged with ease...now all that remains to be answered...how the hell do you cut a thread...BSF and 26TPI will probably all that I'll need to know

Cheers, Dick

You will need a Metric Transposing Compound Gear 127/120 tooth for cutting your BSF thread as well as the associated change gear if you dont allready have it.
There maybe allternatives to the 127/120,others on the site maybe able to assist with the different gear combinations.
Hercus might even still sell the compound gear.

There are other transposing gear combinations apart from the standard 100/127.

You could try 37/47 or 46/36. These combinations are only approximate.

There is a discussion on this subject at Metric transposing gears - Practical Machinist - Largest Manufacturing Technology Forum on the Web

Ken

Ken do those other combinations you mention cover the 127/120,as you have noted the 127/100 which suits the AR.


Dick if you cant find allternative Compound Gears for that TPI you would also require a 39 tooth Gear.

Hi PC,

I'll be the first to admit I know little about transposing gears, only from what I've read.

In answer to your question, I do not know whether other combinations exist, I've never really sat down and tried to work them out.

I guess when I finally get my Hercus AR up and running, and need transposing gears, I'll seek your advice if I can't nut it out.

Ken

Evenin' Guys, Ta for that, much appreciated...

...the truth is I am somewhat off (skill / knowledge),for cutting threads at the moment, that said I do have access to both BSF and cycle thread in tapes and dies so in all likelihood I will stick with these as required.

But thank you anyway...have added the suggestions into the bookmarks.

On the plus side I managed to successfully re-bush a very much elongated stand attachment hole on a motorcycle I am restoring at present...twas the first time I'd made anything using a lathe since 1971...so I'm rather chuffed with myself tonight

Cheers, Dick

Originally Posted by greencan

I managed to successfully re-bush a very much elongated stand attachment hole on a motorcycle I am restoring at present...twas the first time I'd made anything using a lathe since 1971...so I'm rather chuffed with myself tonight

Cheers, Dick

Well done Dick. Mostly my lathes get used to make spacers and bushes - useful and necessary things!

Jordan