revtothelimit - motorbike forum

Well, it's a start.

Top fettling, that man.

It could do with being 150mm higher, it's very low to work on. Easily solved by making a plinth, probably from square straining posts.

I'm back to annoying this thing.

I got the rise and fall gearbox to work, it needed spacing at the front to keep it properly meshed. The thin white line is daylight:



The top of the gearbox is machined flat:



Where it bolts to isn't:

Then there's the casting draughts:





If the castings were square they would come out of the moulds.

It's still a bit stiff but it works. And is more sightly than the scissor jack.

That little hand wheel is moving a big weight up and down . On my mill i fitted a
gas strut off a car tailgate to the side to support the head of the mill.
It helps lift the mill and also takes weight off when lowering so much easier
to turn the hand wheel.

I've been twitching at it this morning, it's not even over the length of the travel. I don't know why yet.

I'd thought about a gas spring, £25 gets me a new on that will allow full travel, about 350mm, and is adjustable. Or I could run a pulley and some weights inside the column.

Another option would be a lead screw type arrangement on the side of the column. That might also solve the lack of column travel locking.

That's going to happen with found materials because it's an itch I now need to scratch.

That, and a new gear would have to be bespoke. And I'm a cheapskate.

That's a yes then:



Even with a bit of old 12mm threaded rod and washer from a washing machine it was smoother and easier. I'll investigate proper lead screws and nuts.

The nut is at the top there which means the threaded rod rises with the column. If I fix the nut to the bottom of the head then the rod will stay in the same position. A small roller bearing will make it even better.

That's a proper lead screw sorted, they won't deliver to here so I've to go to Chesterfield to collect it.

Afternoon of annoying this thing.

Proper leadscrew fitted, complete with a small thrust bearing. It's much better.



Next is to make a proper bracket for the top to replace the scrap strap hinge. But first I need to make some clamps and the like.

Centre drilled:



Drilled:



Fits:

The first cut, a gentle one. No juddering and no squeals, all is good. It's a slow process so I'll get the bulk of the removal done on the lathe.

Version 1.0 of the mounting block. It works but looks lumpy. I'll make another one that'll be more aesthetically pleasing using lessons learned from making this one.

I suspect you have a coordinate drilling machine there, a later version of the colour pics on this page

http://www.lathes.co.uk/perrin-av-1/

especially as it doesn't have a hollow spindle for a drawbar. Uisng a milling cutter is likely to end up with the collet holder coming out of the taper due tot the intermittent loads, with predictable unpleasant results.

Fantastic drill tho, way better than anything else you are likely to use short of a bridgeport or similar.

If you have access to TIG you could weld that gear up and carefully grind/file it back into profile, it's not likely to see high loadings or speeds, so it being bit sift won't hurt. It will probably still outlast you.