Monday 31 July 2023

Speeder reassembly

The time has come for me to reassemble the speeder. Obvs I have left this long enough to ensure I've forgotten how it comes apart and thus goes back together again. But we like a challenge.

Anyway, here are all the bits:


Firstly I will need to reassemble this angular contact bearing which came apart during disassembly:


...then refit the (matched pair) thrust bearings to the output shaft.


The locknut proved a bit of a twat to tighten, partly due to the deformed collar (used to lock it into the slot) and partly due to the nut being fairly insubstantial. From what I can tell, the Knipex adjustable grip ended up squashing the nut, causing it to bind. Anyway, I got there in the end.


Now I need to fit the planet gears in the carrier. Each has a needle bearing and a couple of brass / bronze thrust washers. I can push them in using a small vise:


But one of the thrust washers has been worn down, almost to a wafer. I have a piece of brass that is big enough, so it's lathe time. I don't have the Tree set up for toolpost drilling yet, so it's over to the Bantam for this one.


Drill out 14mm and turn down to 24mm:


Then part off a 1.2mm length to form a washer.



That did the trick.


I cleaned out all of the bearings with brake cleaner. Now I need to regrease them somewhat. Although it looks as if I have fully packed them with grease, in fact the grease is only present on one side of the bearing, so the fill factor is probably less than 30-40% or so.

The planet gears and their carrier go in before the output shaft, unless you want to disassemble it all over again. Luckily I remembered this.



Finally back together, so time to fit the ISO40 / M16 adaptor, held in with some low strength Loctite.


The output shaft seems to be fitted with  Clarkson Autolock (small) collet. John Stevenson had made up an adaptor that fits the Autolock collet at one end and accepts ER11 collets at the other. It's actually composed of an ER11 collet chuck with a taper socket on the end. There's a mating tapered element with the required 5/8" x 20tpi thread - no idea where this came from. It looks like this


So finally here it is back together again.




Here are the Autolock collet and the ER11 collet chuck.


Nobody uses Autolock cutters any more, as they require a 20tpi thread on the chuck end of the cutter. Nowadays people prefer to use ER collet chucks, Weldon shank cutters, hydraulic chucks etc.

In my case, this speeder would tend to be used only for small diameter cutters under 3-4mm diameter, so an ER11 collet would be quite appropriate. This Autolock-to-ER11 adaptor is rather helpful. It's just a pity there's only one of them here and I can't see anything similar on the internet.




Back in their rightful place


Torque / reaction arm:

Speeders require something to prevent the body spinning, rather than the intended output shaft. This takes the form of some form of reaction arm and a fixed vertical rod for it to work against.

As noted, I previously made up a reaction arm for my tapping head for use with The Shiz. This also required me to make up a torque arm to prevent the chuck body from spinning. In the end, I decided that a tension-compression tapping chuck was a far better solution, so the tapping chuck was flung into the tooling rack, never to be used again.

Here's the chuck with its torque arm...


...and the rod that the torque arm picks up on, held up against the speeder in roughly the right position. 

It's got a machined bore to fit the quill of The Shiz and is held on with a pinch bolt. However, as you might expect, the pinch bolt block would foul the body of the speeder in its current form. It's upside down here but you can see that there would be a problem if I flipped it so that the rod pointed down, as would normally do.

So it looks as if I'll need to do some surgery here. It feels to me that I will need to hack off the existing pinch bolt block and fit something more (axially) space-efficient. Doesn't look like the end of the world but needs a bit more buggerage before we are done here.

Saturday 22 July 2023

Welding fiasco - resolved

Last time round, I "just" had to weld the adaptor to the nose of the 40 taper body. Then it would be done and dusted, job done. However, I stupidly handed the job over to The Stupid Fat Bloke. I mean, what could possibly go wrong etc.

Firstly, there's a large (M14) grub screw inside the centre bore that protects the internals from stray muck and swarf from getting into the bearings etc. It needs to go in before Fat Boy welds the adaptor in place. But hold on, if I do that, I won't be able to drift the output shaft out if I ever need to disassemble it later. Hmm.


At this point, I tried a dry fit of the adaptor and found that it jammed into the end of the taper body - it's a light press fit. But when I forced the issue, it turns out that there's a threaded adaptor I'd missed. It's held in with some for  of thread locking adhesive - heating it up had softened it enough to come free. That was a lucky discovery and actually helps me.


So at this point, The Stupid Fat Bloke took over. Rather than set up the TIG welder, he went for the easy / lazy option of the Lidl / Parkside stick welder. Nice piece of kit for the price (£90?) but these things are rather brutal and lacking in finesse.


The result sort of looked OK superficially but it was deadly quick, so the metal below was doubtless rather brittle afterwards, with questionable penetration. More on this later....


It seemed like a good idea to quickly see if the thing actually fits the spindle before going too far down the road. 

For one thing, these drive dogs will need to be removed before the speeder can be fitted. That's not a problem in terms of function - just like the tang on a Morse taper, they shouldn't be imparting any torque as such. Besides, the actual torque in this instance will be tiny, as we are talking 3-4mm cutters max.




No luck. The drawbar screw bottoms out before the taper is tight. I'm going to need to bore out the central hole so that the drawbar doesn't bind on the bottom of the internal thread.



This 16.5mm drill is exactly what I need. The Drill Doctor thing cleaned up the chipped edges reasonably well:



Done. It's 16.5mm all the way through to the fully threaded portion.


Time to retry it in the spindle. We must be getting close now?

Ooops. The weld snapped - as mentioned before, the stick welding event was very brief and of questionable penetration.

Bollocks - time to move the machinery round and bring Bertha the TIG welder into play. No, I didn't name it - that's how it was known in its previous habitat before I acquired and repaired it.


It needs to go where the black tool cabinet is, so that it can reach the 63A socket you can see on the corner of the wall.


Sorted. 


Now to TIG weld the thing. I won't let The Stupid Fat bloke try his hand at TIG, so will do this myself.

That's better.



Note the obvious difference here. The Thread on most of my tools doesn't start until 9-10mm into the bore. Let's get it in the lathe (again) and rectify that.






That looks better. We must be getting somewhere now, surely? Well, nearly. There's now excessive weld penetration on the inside of the bore, causing the drawbar to foul before it has tightened fully. A bit of action with a carbide burr and an M16 tap and we are (finally?) good.


Cleaning out the thread took its toll on the M16 tap. This was bought as a used tap in an assortment of sizes. It's not going to be much use for tapping new threads now, with half of the teeth missing. I won't throw it out though, as it can be used to clean / chase threads.


Finally, I have a taper body that work with the machine. That was a bit of a marathon but finally I can get back to reassembling the speeder itself in the knowledge that it's likely to actually work....

"All" I have done here is weld an adaptor on the end of a taper toolholder, taking perhaps 2 hours in the process. I'd starve to death if I was doing this for my day job.

Sunday 16 July 2023

Butchering the speeder

Before getting busy with the chopping tool, a few measurements:



I have a couple of these adaptors. They are intended for converting a BT40 toolholder into an ISO40 toolholder. By cutting off the male threaded section, I have a ready made ISO40 nose that I can simply weld onto the butchered speeder taper.


Chop chop and cleanup:
No picture of the angle grinder action itself but here's the aftermath. Now I need to face off the end of the taper and ideally also bore the end out to 17mm to suit the adaptor. There's <10um of radial runout here which is good enough for what I need and I can't be arsed to mess with it any further. It's really muggy at the moment and I'm not enjoying being out here, being a fat bastard.


Anyway, here we are, ready for action:


Other stuff came up, so play ended here. 

Next day. Still pretty muggy but I'm getting impatient!



Face off the end...


...and chamfer.


Now for the boring part:



Ready


Go


Not bad. I need to accommodate a 17.00mm shaft


Looks OK. It's not through hardened, so wasn't a big deal.


More chop chop:
Ideally I'd have cut off the threaded section so I have a go / no go gauge for the boring operation. But the bore is spot on 17mm, so should be a good fit.


Before finishing with the lathe, time for a quick clean up with some fine paper to get rid of the light rust marks. Of course, The Stupid Fat Bloke had jumped the gun and removed the carefully set up part. But for a quick touch with emery paper, it doesn't need to be anything more than clamped in the chuck. That's better:


A pressing situation:
The threaded adaptor is actually a nice press fit. I need to push this into the main body, leaving 28mm from the shoulder. It's still got ~3mm to go:




To get there, this gap needs to come down to 0.6mm although I doubt it's critical, given how coarse the thread is and the nature of the drawbar system.


There's the 0.6mm gap - this will be fine for the weld.


I need to TIG weld it. 2 spots on the spanner flats will do the trick, as it's only withstanding the drawbar tension. It's what I've done previously and it's worked out fine.


But first, I need to remove the blue plastic ring which would otherwise perish:

Weld it up?
Ooof - slight logistical issue there. I had to move the big old Miller Interlas TIG welder to make way for the Tree lathe and the cable isn't anywhere near long enough to reach the 63A socket now. So I can either move the beast, make up a 63A extension, use the MIG welder or go full agricultural mode and use the stick welder. The jury is out on that......

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