Thread: Extended Cross Slide Casting for Hercus

Hi I have one of those cross slide castings , I havent been game enough to machine it yet. I saved the step by step write up done by the woman on the US forum, forgotten her name . Mike

None of the machining is overly difficult.

Time wise you could probably knock it over in a couple of days if not quicker depending on how many hours you want to work and the type of machine and available tooling you have,ability/experience.

When you get around to doing it make sure you plan your operations before starting,( measuring the casting,compare to your original)
there is enough meat on the casting,but don't rush into finish machining either the top or bottom.

With the casting Ben had some had to be machined off the front of it.

Up to you what tooling you prefer to use but for the top and bottom faces I used a Fly cutter.

Apart from a vice I used an angle plate and clamping direct to the mill table for work holding.

Mike,
I think Paula is the woman you are referring to.

Bob & pipeclay,
It sounds like using the lathe to machine the dial clearance is the go. In addition to quill runout, my PD is prone to dropping its chuck out of the MT2 bore when it encounters chatter. That could be messy when fly cutting!

Yes.

Yes Paula , she wrote up a good article on machining the cross slide casting - with many pics .


Ok PC thanks for the tips , I have a 45 series mil/drill . Yes OK about the flycutter , I thought that's what you did for the final passes . I will not rush it , I need to buy a slotting cutter , I do have the dovetail cutter.

Clamping the cross slide onto the saddle could become fiddly due to the height of the set up. You blokes with 260s might be able to utilise the front located traveling steady mounts to jury rig something up. I think it would be easy enough to mill the recess with the slide rigidly clamped to the milling attachment. Maybe a task best suited to power feed if you used a cutter like mine.

I wonder why Hercus recessed the boring table and not the extended slide?

BT

I found the thread by Paula

Machining A T-Slotted Cross Slide

Thanks for the setup photos Bob. If I end up buying the extended cross-slide from the bloke in the UK I will use that setup to machine the clearance for the dial. I can see so many benefits with the extended T-slotted cross-slide, I reckon I'll bite the bullet and stump-up the
cash.

What type and size cutter is that you have in the photo?

Chris

Originally Posted by morrisman

Yes Paula , she wrote up a good article on machining the cross slide casting - with many pics .


Ok PC thanks for the tips , I have a 45 series mil/drill . Yes OK about the flycutter , I thought that's what you did for the final passes . I will not rush it , I need to buy a slotting cutter , I do have the dovetail cutter.

When it comes time to purchase a Tee Slot cutter you may find it hard to source one of the specified size.

I think they call for 3/8" slot with a 7/8" Tee,the Tee size is easy to find but one with a 3/8" shank not as easy,most have 1/2"/12mm,
the wider slot will cause no problem.

Originally Posted by morrisman

I found the thread by Paula

Machining A T-Slotted Cross Slide

I had forgotten what a pleasure it was to read and view Paula's posts on PM. I have a few years of catching up to do. Thanks Mike.

Originally Posted by jack620

Thanks for the setup photos Bob. If I end up buying the extended cross-slide from the bloke in the UK I will use that setup to machine the clearance for the dial. I can see so many benefits with the extended T-slotted cross-slide, I reckon I'll bite the bullet and stump-up the
cash.

What type and size cutter is that you have in the photo?

Chris

Chris.

It's an eight flute 1 5/8" English Presto. Space permitting, my end mill of choice.

Bob.

Thanks Bob, I'll track one down.

Originally Posted by jack620

Thanks Bob, I'll track one down.

Chris sent me a PM. I typed the reply below but his mailbox is clogged.....

Originally Posted by jack620

Hi Bob,
I went searching for a 40mm Presto end mill like yours and found this on EBay. Nearly died when I saw the price.
$124 plus postage for a used one! Is that about what I should expect to pay?

Chris

Threaded (25mm) shank end mills 8 flute 40mm dia PRESTO ......................94 | eBay

Hey Chris,

You need to keep looking. I think I might have paid about 30 quid for mine around 5 years ago. Just bear in mind that these big cutters need a bit of grunt to turn them. My little Hercus mill with its half horse motor struggled. The Schaublin copes with 2 horsepower.

Another thing to be aware of is that the Hercus milling attachment has only one bolt clamping the slide onto the cast mount. Same setup on the dividing head. A big cutter and a greedy cut can knock the workpiece out of whack. Guess how I know.

Good luck
Bob.

PRESTO HSS END MILL 1 3/4" X 2 1/2" GROUND SCREWED SHANK C251 | eBay

DORMER HSS END MILL 1 3/4"" X 1" SCREWED SHANK C251 | eBay

Thanks Bob,
Seems I need to clean up my inbox. It would be nice to get a warning from the forum before it was full.

Thanks for the eBay links. Looks like the bloke with the used Presto for $124 Oz is dreamin'.

My Hercus 260 has a 3 phase 3/4HP motor. I guess it would cope with a 40mm cutter with shallow cuts?

Yep, I've only had my milling attachment a couple of months but I've already managed to smack the attachment out of alignment by being a bit too keen with the cut. And that was only a 7/16" end mill.

Chris

Hi Chris,
When you log in it comes up at the top that your inbox is % full and you need to delete things when it's getting close.

Dave

OK, thanks Dave. I'll keep an eye on it.