Thread: cross feed screw

Wouldnt worry to much about having slots underneath,when you offset the toolpost and lock it done in what ever position you choose it wont move.

Looks nice but a lot of extra work for virtually no benefit as far as I can see.

Originally Posted by azzrock

looks good but i dont have acces to a indexing head for the slots underneath.

This is how they did it on the Hercus 260. You do not need an indexing head, careful marking out and drilling the index holes is fine.




Me personally, I hate this indexing thing. I am used to set the toolpost to any angle that best suits the job at hand, and this is very rarely exactly in 90 degree steps. With this indexing device I have to undo the locknut about 2 revoulutions to release the toolpost from the spring loaded index pin in the topslide. On a toolpst without indexing "feature", only lightly loosening the locknut is sufficient to rotate the toolpost into position.

Consider a quick change toolpost instead. Either homemade, or bought. There are China made Aloris clones on the market. Especially now with the US$ so low, one can order from the US and get it including postage for well under the cheapest offer in Au. Mine should arrive next week or so.... Then I will sell the 4-way post pictured above including all it's toolholders.

Chris

the south bend nuts on US Ebay for $39-ish might fit?

would the south bend nuts on US Ebay for $39-ish fit? I think I said this in another thread accidentally

Cant see why not,they appear to be the same.

Originally Posted by neksmerj

nadroj,

Well spotted, if you have details of the thick washer, I'll include it with the other drawings.

I presume it sits between the main block, and the top of the compound slide. I don't actually have my lathe up and running yet, so didn't realise it was missing.

Ken

My washer measures
OD= 60.2mm
ID= 12.7mm (plus an imperial smidgeon for stud clearance).
Thickness= 7.0mm

There's an indexing peg pressed into it, at 25.4mm PCD.
The washer has a 6.35mm hole for the peg.
The peg is
Length overall= 10.0mm
Length of portion pressed into washer= 6.7mm
Length of head= 3.3mm
The shape of the protruding head is tapered 10 degrees where it engages with holes in toolpost body.

All edges are slightly chamfered, except the OD edges of the washer which are left square.

Some of your dimensions are different from my toolpost's:
Main body
- Your 37, mine is 36.5
- Your 30, mine is 31
- Your 6.7, mine is 9.1
- Your 19, mine is 19.4
- Your 15, mine is 15.1
- Your 40.7, mine is 43.6
There are 4 indexing holes on the underside corners, 6.5mm deep with tapered edges, located and sized to suit the peg in the washer.

Stud
- Your 15, mine is 19.4
- Your 50, mine is 50.6
- Your 76, mine is 81
- Your 19A/F, mine is 18.1

T-nut
- Your 62, mine is 39

There's a spring: (not shown in photo)
ID= 23mm
wire diam= 2.6mm
No. of coils= 2.5
Length uncompressed= 22mm

The peg with its indexing holes must be carefully made, because it isn't spring-loaded like on the 260. If the thing is annoying, turn the washer upside down so the peg is in the toolpost slot. That works with my 39mm long T-nut, but wouldn't with your longer one.
The 260 doesn't use a washer - the toolpost bears directly onto the unslotted topslide. I'm not sure how the 260's optional slotted topslide (which I've only seen photos of in the parts book) is supposed to accept the 4way toolpost - possibly only meant for lantern type toolpost.
Although some of the dimensions are clearly not critical, others are quite different possibly due to factory redesign?

Jordan

Hi Jordan,

Thanks for all the dimensions of your tool post. It's interesting that there are quite a few differences, clearly, several versions of the same thing exist. Mine does not have any indexing features, as yours does.

I purchased mine from a chap who had several Hercus 9" lathes in his shed, so I assumed it was a genuine Hercus made item. It may not have been.

Ken

Ken I wouldnt venture outside for the next few years if its not ORIGINAL,the (HERCUS GOD) might hit yiou with a bolt of lightning.

Peter,
No pedants or cargo cultists around here I'm sure.
These details only matter if they matter.

Jordan

PC,

The next time I'm out in the yard, I'll make sure I'm wearing my Hercus tin helmet, with a copper cable running down to some copper plates, fixed to the underside of my Hercus safety boots.

Both hat and boots are painted Hercus green. Am I a Hercus head?, you be the judge.

Ken

what a wealth of info cant make up my mind between the first one posted on this thread or an adjustable style one posted earlier in this forum. shimming the tools can be a pain in the ####.
thanks have a good day.
azz

> shimming the tools can be a pain in the ####.

If you go for a 4-way toolpost, you want to go also with the old style HSS toolholders, those that present the HSS bit at an upward angle. They were sold by Hercus along with the 4-way toolposts. You do not use shims on those, instead you slide the HSS bit in or out until the tip is at center height.

If you use more modern tools with a 4-way toolpost, it is good practice to store the shims together with the tool. Each tool has its own shims and tool and shim are stored together in individual glass jars or similar. If you use HSS or brazed tools, it may be necessary to choose new shims after each regrind. But if you use indexable insert tools, the center height (and the shims) never change.

If well set-up, and you never need more than 4 tools at a time, then a 4-way toolpost is as a matter of fact faster to use than a so called "quick change" toolpost. You tend to cut your hands on the tips of unused tools in a 4-way toolpost though.



A good quick change toopost is a joy to use if you can afford it, especially if it is of good repeatable accuracy, and especially if you buy it with at least a dozen empty toolholders.

Stay away from the very cheapest quick chhange toolholders. I bought one made in India about 10 years ago, only to toss it in disgust into the rubbish bin. I then made my own to the same clamp design, one that is properly finished and fits the homemade toolholders, and I still use it on the smaller lathe. You can make your own dovetailed QCTP, if you have a vertical slide you can even make it all on the lathe. It is a very rewarding project. You can also find a dozen plans on the net to make your own, easy to scale up or down to suiy your lathe. There are plans for several types of clamp, for piston and for wedge toolposts. Chris

i have a few traditional hhs tool holders. but was hoping to use tip tool manly. now that i have seen the joy of them on some bigger lathes at work. i am having trouble getting a descant finish on the hercus thow.
i was looking at this tool hold.
http://members.optusnet.com.au/clear...s/article1.jpg
http://members.optusnet.com.au/clear...s/article2.jpg
i like that the hight is adjustable.
thanks for your advise

Are you machining Mild Steel.
What type of tool are you using.