Member postings for Lee Jones 6

No, that's the end of the cut. It started shallow then went progressively deeper.

The cutter started to spin in the collet near the end, then carried on going, then span at the very end.

I was cutting from right to left on the edge closest to me - I think this is conventional milling.

Edited By Lee Jones 6 on 19/05/2020 14:15:28

**LINK**

Chinese facemill/inserts.

In steel, with both 50mm carbide facemill and 10mm HSS endmill.

CHEAP! :D

I'm certainly not concerned about tipping it over. It takes all my weight and lifting power to tip it enough to get something underneath it (rollers, etc). I just want it to stop sounding like it's going to bring the house down if I take more than 1mm DOC.

Don't worry, that's an old picture. I have since wired 6 new sockets into the existing ring main.

I'm pretty sure the garage is free of such subterranean impediments.

I wasn't climb milling (at least I don't think I was). Which picture are you alluding to?

I believe I'm inserting it correctly. The collet is gripping the plain shank and I did it up pretty tight.

1mm DOC. The cutter was touching, but not cutting the bottom of the slot at the time.

The current set-up is currently limited to ~1mm DOC before things get too loud and shaky.

However, I'm planning to rectify that shortly: Stabilising a Milling Machine

How hard should it be possible to push such a machine during various types of operations?

I was afraid you'd say that.

If it were to do that, would you suggest putting rubber between the base and the floor?

Or would metal-concrete be better?

After taking the time to clean, square-up, mill to size and slot a part:

When it came to widening the slot (from 10mm to 22.8mm), the 10mm 4 flute milling cutter decided to dive into the work:

... and I have no idea why.

The part didn't move (it was still tight on it's parallels), so either the cutter was pulled from its holder or the quail was pulled down. However, although the quill was not locked (is this compulsory?) it was set to wheel (rather than big-pull-down-leaver-thing [scientific name]).

Any ideas?

I've been meaning to fasten down or otherwise stabilise my Warco Super Major Mill for some time now. Even with everything secure and the gibs tightened, it still has a tendency to vibrate (a lot) and wobble (a bit) on it's current flat base.

However, I'm not quite sure of the most favourable means to accomplish the task. The issue is my lack of trust in the quality of the concrete in the garage and the fact that I'm not keen on drilling a bunch more large holes in the floor.

Is there another way to gain a similar level of rigidity? Perhaps some rubberised feet?

In the headstock gearbox? The little shiny spot on the dirty section of paint? Or something else?

That's a good question. This was the muck that came out of the SC gearbox.

Head gearbox looked okay, but I dropped and changed the oil anyway.

It would surprise me if the delrin swelled further. It took 25 years to get it to the point of binding.

However, if this does happen again, I can either add the same mod to the other end or turn down the cams.

The odd thing is, the cams on the right of the picture (3 and 4) were the worst. 3 was causing the bind.

I will be careful, promise.

After ~2 years of searching, I finally managed to source a suitable lathe.

She's a 1995 Harrison M300 - Long Bed [40"]

Pretty, no?

I actually took a bit of a punt on this one, as Covid-19 prevented a viewing.

Most things turned out well. It's in pretty good condition overall.

However, when I tested the screwcutting gearbox, the feed selector was jammed and the leadscrew skipped.

I feared the worst; chewed-up gearing, missing teeth etc. My heart sank.

After some guidance from the wonderful folks over on the Harrison Lathe Group (https://groups.io/g/HarrisonLathe), it transpires that there are a couple of known issues with the M300 SC gearboxes. Firstly, the oil can gum up the workings. Secondly, the delrin cams can expand over time, ceasing the feed selector. Hopefully it's one of these issues.

Well, there's only one way to find out.

The gears look like they're in good shape - no missing teeth. Phew!

Gave it a good clean and fished what turned out to be one of the external plugs out from under the cams. No idea how it would have made it into the gearbox. I had hoped that this was the cause of the jamming. No such luck I'm afraid.

Anyway, gave her a good clean.

I'll save you from all the gory details (for those wishing to delve into those you can see the link just below). The issue was expanded delrin cams. There are a couple of options available to fix this. Firstly, one can mount them on an arbor and turn them down. However, since I have never used a lathe before, let alone turned delrin (requiring a honed HSS tool turned not too fast so as to melt it, etc) and the fact that they are an expensive part to replace if I mess the up (£160 - thanks Harrison!), I decided on the second option.

https://groups.io/g/HarrisonLathe/topic/m300_newer_type_screw/73407135?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,0,73407135

Option 2 was to capitalise on the fact that any movement (i.e. any direction) of the cam follower shaft seemed to free up the binding. So first I made up a new cam follower shaft (so as not to chance scrapping the original part), turn down one end and place it into a brass cam, which can be tuned.

This is my first ever turning operation.

Faced:

Turned down to the same diameter as the original part (bang on ).

Centre then twist drilled:

Reamed:

Hex milled on the end for fine tuning (this is to be removed later):

Tuned:

Hole for grub screw drilled:

Tapped:

Fit-up:

And ... it verked! \o/

Phew!

Edited By Lee Jones 6 on 17/05/2020 09:48:21

Edited By Lee Jones 6 on 17/05/2020 09:48:37

Edited By Lee Jones 6 on 17/05/2020 09:49:33

Going to do an Arc Euro Trade order in the near future.

Thinking about going for the no brand Telescopic Bore Gauges.

Assume this is a generic import product.

Does anyone have them? Are they any good? How do they compare to a named brand?

Same goes for thier micrometers? Can they be trusted?

Is this just another case of 'you get what you pay for'?

Right, the size limitation was one reason I decided against the scissor/clamp style.

I read about the toolpost rotation issue in a previous thread.

My toolpost is the T1 T63 type. I need to check if it has the anti-rotation pin fitted.

Went for a large 2 wheel push-in forming type; with fine, medium and course wheels provided ans a package.

A nutcracker type knurling tool has also been placed on the 'to-make in the future' list.

Thanks for all your help and advice.

With regards to conventional style knurling tools, what the the benefits to single or double wheeled tools?

Currently in the market for a knurling tool.

I understand that the scissor/c-clamp style puts less pressure on the spindle than the push-in style, but that's about the limit of my knowledge presently.

When are c-clamp style tools not the best option?

Does anyone have any product (bought rather than made [maybe further down the line if this doesn't work out]) recommendations that have served them well?

What does a 6 wheel model offer? Are they just 3 different patterns located on the same tool?