Thread: Slotting - A Rough Attempt

Here's my recent attempt. I wanted to make gears with it, hence the toolhead. But I found out how hard it is to hand grind a form tool for gears. It cuts ally ok, but steel would be hard going. Maybe ok for small internal keyways.

Excellent work Bob, the only thing I would ad are oiling points...

I think every shaper/slotter I have seen has scored rams from lack of oil...

Bryan, Impressive, the slotter looks shop bought! Dont you blokes have a macro setting on your Kodak Instamatics? How about addtional detail on the tool head.

RC, I was toying with the idea the idea of zig zag oil ways in the ram or ram guide but ran out of puff. Deckel lubricate the ram in their FP slotting heads as per the attached photos.

Bob, it is bought insofar as I used a pair of linear bearings that I picked up cheap on fleabay. I just lashed them onto a kind of 'raft' structure, made of driftwood and coconut fibre, as you can see.

Yes my camera has a macro setting but the trouble I seem to have is with the stupid operator getting either flash glare or blurring. Also it shows up my work a little bit too well. But if you insist...

Originally Posted by Anorak Bob

Hello Frank,

Nice work. I have to make one. Any chance of a few more detailed photographs?

To cut keyways in tapers do you simply eyeball the ram against the work piece (or use an indicator) to ensure parallelism and tighten the base plate bolts?

I imagine it does not require anything more complicated than that.

Bob.

Hi Bob,

By an extraordinary piece of luck I found the original MEW article first try - my filing system is not usually that good! It appeared in MEW August/September 1991 issue. If you PM me with your e-mail address I'll scan it for you (3 pages including the dimensioned drawings [for a Myford sized lathe] The Brackenbury and Austin has a bigger swing). Obviously I can't post these for copyright reasons though. I can certainly take extra photos if you need them, but what you see in the one I posted is about all there is to see. Let me know if you would like to see other views though. I could also briefly describe what I did when fabricating it to make sure the ram was actually on centre height for the B&A lathe in the finished article if it would be helpful.

You can match tapers pretty well by eye, or by using a sharp pointed tool to scratch the taper surface in the keyway location prior to starting cutting. You could, of course, use an indicator for absolute certainty - depends on how much precision you need.

Frank

Bryan,

I like the removable toolhead and the way in which you have dealt with the skewed slot. Do you have another head for internal slotting?

Is the vertical handle another reference to Thor Heyerdahl's Kon Tiki? A mast?

I would have thought a horizontal handle would be easier to use simply because you could get your body behind it.

Whilst you have utilized commercial bearings, do you reckon a line bored block of cast iron would do the job?

Finally, how did you index the lathe spindle when you cut your gear?

Bob.

Frank,

Last year a bloke gave me a swag of old MEWs and I have the issues either side of the one above. Funny how they all have an old codger featured on the cover !

I tried to send you an email yesterday but there was a glitch with the system.
I 'd really appreciate those scans. I will have another go at a PM.

Bob.

Bob, yes a different head would be needed for internal work but I haven't made that yet. Now that I have a shaper it may never happen.

The vertical format just happened to suit the framework, which in turn was just the simplest method I could think of that used the materials I had. I was a bit worried about the ergonomics but it's fine. In fact it may be better because you can get your shoulder behind it. However my lathe is on the low side so that may be a factor.

The bearings are just plain bronze bushes, so I'm sure cast iron would be fine with suitable lubrication. They do take a bit of side load though.

For the test piece pictured indexing was achieved by rigging a pointer on the bull gear. My intention was to later use the 'printed scale stuck on the chuck' method.

Bryan,

One of the more useful accessories that I have made for my lathes is an expanding mandrel to facilitate manual turning of the spindle. Great for threading to a shoulder.

My version utilizes a standard Hercus cast handle which is readily removable. I made the projecting end 1/2" in diameter so that it would enable it to fit into a chuck mounted in my Vertex rotary table.

I've used this setup, located on the table of an incomplete pedestal drill press, to graduate the rotary table, dividing head etc that I've made. It has worked flawlessly and would work in a similar fashion for accurate slotting.

After RC's comment about lubrication I popped the head apart to see if there was any simple way to introduce some oilways in the components.

What I found were wear marks in only a few places which indicates a pretty poor fit between the mating surfaces. The chatter that I was experiencing in not going to abate unless I get out the bearing blue and the scrapers.

Not a task that I really look forward to as I've done very little of it before. The last thing I want to do is stuff the thing up in the process of trying to fix it.

Bob, I like your lathe indexing setup. Very clever.

If you don't want to scrape, ask RC if he'll do it for a slab. He's quite the veteran these days.

Bob the indexing head on the lathe spindle is brillant.
I'm going to have to get me one of those one day.

Stuart

p.s. You've made me realise I can use the handle from my shaper for a spindle crank

Stuart,

What worked out well with the removable crank is that you can leave the mandrel in the spindle. Very handy.

Bob.