Thread: Hercus 3A T&C grinder

I didn't know about balls to support the table on Hercus 3A. An upgrade?

Jordan

Originally Posted by nadroj

I didn't know about balls to support the table on Hercus 3A. An upgrade?

Jordan

In all honesty I'm not that familiar with Hercus machines in general (my first one) let alone the family of T&C grinders. I have read that the No.1 and No.3 had "regular" V ways and the 3A came out with balls on "linear" hardened ways or tracks. I know that it's standard on the 3A because of several searches on this forum and receiving advice from Anorak Bob.

It's certainly a clever and interesting method. The hardened tracks are also removable and held in with cap screws although I dare not remove them for fear of never getting them "just right" again.

It also occurred to me that if the ways are badly worn, would replacing the balls with slightly different diameter work? This would mean they would seat in a different (unworn) spot on the V. Only issue I can see is one side on the bottom is flat and so would not help and also the rack may not mesh properly with the traverse. Anyway, no need to worry about any of that with this machine, but I do like to think of stuff like that!

I'm taking them to work tonight to burn the midnight oil cleaning some parts, including my balls. If I don't receive any advice on the balls, I'll be inclined to just throw them in the tray with turps and clean them all together.

Cheers,

Simon

Ouch my neck hurts.....
The balls should all be identical, so no need to number them. Though i guess its too late now anyway....

You can't just change the size of the balls, as one runner runs in 2 V's and one runs on a V and a flat. If you go to a bigger ball one of the runners will sit up higher than the other. I think.....

Once apon a time you may have been able to get new tracks to replace the old ones. I'm guessing not any more however there are companies in the states that sell retro fit kits for grinders. Can't imagine they would be cheap though.

Ew

Thanks Ueee, I figured they must be identical, or should be anyway. WRT the balls I see what you mean, because one side is V on V and the other is V on flat the result would have an affect of tilting the table and throwing off the vertical alignment. I figured that the intent of the track removal was for replacement but I bet they would cost more than a S/H machine!


Any idea when these things were made? There is a stamp on the table: 3A-679 would this possibly mean it was made in 9th month of 1967?
Edit: Oh wrt the balls I didn't number them but I kept each side separate.

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Cheers,

Simon

Spent a bit of time cleaning parts today.

Tonight I just finished cleaning the table. I removed the top half of the table from it's base to give it a good clean. There was a fair amount of crud, build up of grinding dust and some rust. I used some steel wool to get most of it off. I may just lightly run a silicon carbide lapping stone over it. It is still stained but if you close your eyes you can't feel anything.

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Cheers,

Simon

Originally Posted by simonl

In all honesty I'm not that familiar with Hercus machines in general (my first one) let alone the family of T&C grinders. I have read that the No.1 and No.3 had "regular" V ways and the 3A came out with balls on "linear" hardened ways or tracks. I know that it's standard on the 3A because of several searches on this forum and receiving advice from Anorak Bob.

It's certainly a clever and interesting method. The hardened tracks are also removable and held in with cap screws although I dare not remove them for fear of never getting them "just right" again.

It also occurred to me that if the ways are badly worn, would replacing the balls with slightly different diameter work? This would mean they would seat in a different (unworn) spot on the V. Only issue I can see is one side on the bottom is flat and so would not help and also the rack may not mesh properly with the traverse. Anyway, no need to worry about any of that with this machine, but I do like to think of stuff like that!

I'm taking them to work tonight to burn the midnight oil cleaning some parts, including my balls. If I don't receive any advice on the balls, I'll be inclined to just throw them in the tray with turps and clean them all together.

Cheers,

Simon

Simon,

The No 3 had vee ways. The 3A and its revised successor, the No.1, both had the table mounted on hardened balls running in hardened steel tracks.

How smooth was the table traverse? My 1's is silken and traverses effortlessly.

BT

ps. Don't be misled by the information Tony Griffiths has on his lathes.co site. What he is calling a No. 1 is a 3A.

Hi Bob,

That explains the heading No.1 and then the first and biggest picture is a 3A. It confused me at first but at the start all I knew was that the T&C for sale was what was in that pic. The small perpendicular hand wheel is the biggest give away.

It's a beautiful machine I must say. I took everything apart and cleaned it and back together. Everything fits beautifully and it's simplicity at it's best. Even the taper dowel pins (in lie of those awful roll pins) that fit the bevel gears on the shafts etc are a joy to drift out and put back. If they don't almost fall into place then you know that it's out of alignment. The ball bearing table takes a bit of getting used to. A couple of times I've nearly send it flying (lucky for end stops).

Yes, if the rest of Hercus stuff is this nice then it won't be my last acquisition bearing the Hercus name.

Cheers,

Simon

Simon
Hercus equipment in my opinion is first class.
Bob & I have often commented on the workmanship of Hercus.
They made things good, unfortunately, a lot of Hercus machines have been abused & had rough treatment.
When you find a good one, suggest hang on to it !
regards
Bruce

Simon,

Here's a link to a site has has some pretty comprehensive Clarkson information should you wish to find out more about your hybrid's spindle - http://www.bedroom-workshop.com/index.htm

Bob.

Thanks Bruce & Bob.

I couldn't help myself, I have dis-assembled the spindle. Nothing hi tech there, just a shaft and a couple of 7100 taper roller bearings. Wasn't sure what I would find to be honest. Was half expecting a P4 or P5 precision bearing but I guess it's not a SG as such. I guess as nice as it is, as it really would be a compromise to use it as a SG. Anyway I'll give them a good clean and put them back. I'll have a good look at the race, any hint of wear and I'll replace them.

So, if I were to acquire a spindle and a dead centre, what sort of quality could I expect if I were to use it as a cylindrical grinder?

Cheers,

Simon

Originally Posted by simonl

Thanks Bruce & Bob.

I couldn't help myself, I have dis-assembled the spindle. Nothing hi tech there, just a shaft and a couple of 7100 taper roller bearings. Wasn't sure what I would find to be honest. Was half expecting a P4 or P5 precision bearing but I guess it's not a SG as such. I guess as nice as it is, as it really would be a compromise to use it as a SG. Anyway I'll give them a good clean and put them back. I'll have a good look at the race, any hint of wear and I'll replace them.

So, if I were to acquire a spindle and a dead centre, what sort of quality could I expect if I were to use it as a cylindrical grinder?

Cheers,

Simon

Simon,

I can't comment on the attainable finish because I haven't yet tried out cylindrical grinding (or any grinding ) on the No.1 yet. I'm looking forward to a bit of experimenting.

Here are some photos of Mickey Mouse setups I had tried on the No.3 in the absence of proper tooling. I'm not suggesting you need to start tracking down Hercus accessories but the photos might suggest some easy make dos with a few basic bits of tooling. The dividing head setup was a way of possibly overcoming the excessive wear in the table by angling the head and tailstock. The mill photo simply shows the flexibility of a lathe milling attachment combined with an indexer.

BT

Thanks Bob, You have been extremely helpful. Those pics are of showroom quality (Donna Hayes) that I have come to expect from you!

First things first I suppose, so I have just made up some T nuts since none of my other sets will fit it. The thin part of the "T" is 1/2" and so I can only assume the thread may have been 3/8" or perhaps 5/16"? I'm not that good with imperial! I propose to make it M8. I was going to go for M10 but that would only leave 1mm of meat each side. M8 should be plenty for what this thing will be doing. I reckon I would still rip the T nut out of the table before stripping an M8 thread anyway...

Later I am going to try and kill 2 birds with one stone and make a ball/radius turning attachment for the lathe and make perhaps make an adapter so I can use it on the T&C grinder too.

Edit: PS WRT surface grinding, I'm assuming it will be a compromise compared to a dedicated SG. It would have to be. But, for many of my projects, just having the option of a ground surface (even for athletics) will be handy. As someone here mentioned, just having something to be able to grind down a washer for a shim will be attainable.


Cheers,

Simon

Simon,

The original tee bolts are 3/8" BSW threaded with a 7/8 x 7/8 base. The thickness of the base is about 1/4 ".

On the beater the tee slot was rooted, its upper surface riddled with dents. My plan at the time was to run a tee slot cutter through the slot to knock off the projections. Didn't get to it in the end. I still have the 3 table and sub table but they may both end up as fodder for some other project because with the No.1, Hercus changed the table's handing.

Peter Fou, the fellow I purchased the No.1 from, did use the grinder for some cylindrical grinding along with some surface grinding. He threw in a neat little Indian magnetic chuck for me to have a go at the latter. Maybe some simple washer thinning.

BT

Well, I did M8 and when I looked at them they looked a bit light on so I re-drilled them and re-tapped to M10. They look better now. There is just enough meat in the T nut to allow for M10. I'm thinking I should have gone 3/8 since the table hold down bolts are probably 3/8 too. Now it's got metric AND imperial. I'll need a million and one spanners to work on it now! Oh well, it will just be like old times… working on my landrover series 111

Edit: yea I metricised the T nut dimensions too. They are 16mm high, base is around 20mm wide and about 6mm thick. They fit nicely.

Simon