*new* anyone with a lathe near East Kilbride (go to page 2)

[skylinedave]

I do some machining and I spoke to my mate who said if it's hardened you can just grind the top hardened layer off before machining but then you will obviously need it hardening again. I do not think any engine shop will struggle with it.

[foxy99]

Thanks again s'l'd'

I posted about this on the Mig Welding Forum (they cover virtually everything over there not just MIG) and workshop.org and got lots of useful information but best of all someone offered to do it for me for a couple of bottles of red wine

Meantime here is a link to a video someone flagged up of hardened metal being cut in a lathe. Looks a bit fierce

sparks fly as hardened steel is cut on lathe

[foxy99]

Hi guys. For anyone that is interested the sprocket is now done. The guy who did it has put the video on YouTube.

here's the link

[skylinedave]

You landed on there feet there , a right proper job !

Nice lathe he has as well !!

[foxy99]

Yeah. It was worth persevering, trying various forums etc and turns out the guy is a bit handy and seems to do all sorts of stuff.

I've sent him something for his trouble and the sprockets came back today.

Might be pushing my luck now but have asked if he can sort the sheared-off M6 studs on my Honda SS50 cylinder head.

Only been wanting it done for 28 years lol

[foxy99]

Well I'm back with another small engineering task. Am sure this time it won't be as complicated as the RD250 sprocket!

I want a drift made-up, to remove the valve-guides on Honda 50cc head.

They are approx 3cm long and have ID of 5mm and OD of 10mm.

So I'd like something of 10mm diameter that could 'follow' the guide out of the head (instead of stopping short when the bottom of the guide gets flush with the head) and with a 'nose' that would fit inside the guide to centre it and keep things snug during the drifting operation.

To give it more oomph I'd like the body of the tool to be bigger than 10mm.

So I'm thinking start with a 20mm diameter steel bar. That would be your handle. Turned down to 10mm for twice length of guide (< or = 6cm) with a 5mm nose on it for sitting inside guide (say 2 cm).

I've no idea how much a firm would take for turning this down but if it's charged by the mm could go down to say 17mm bar or 15mm but am thinking the smaller you go the less effective the drift becomes.

Any thoughts?

[foxy99]

bump

[namless]

Jan 3, 2017 14:59:56 GMT foxy99 said:

Well I'm back with another small engineering task. Am sure this time it won't be as complicated as the RD250 sprocket!

I want a drift made-up, to remove the valve-guides on Honda 50cc head.

They are approx 3cm long and have ID of 5mm and OD of 10mm.

So I'd like something of 10mm diameter that could 'follow' the guide out of the head (instead of stopping short when the bottom of the guide gets flush with the head) and with a 'nose' that would fit inside the guide to centre it and keep things snug during the drifting operation.

To give it more oomph I'd like the body of the tool to be bigger than 10mm.

So I'm thinking start with a 20mm diameter steel bar. That would be your handle. Turned down to 10mm for twice length of guide (< or = 6cm) with a 5mm nose on it for sitting inside guide (say 2 cm).

I've no idea how much a firm would take for turning this down but if it's charged by the mm could go down to say 17mm bar or 15mm but am thinking the smaller you go the less effective the drift becomes.

Any thoughts?

Doesn't really need to be 20mm. If the OD is 10mm. 12/14mm bar for the handle should be enough, down to 9mm for clearence, a shoulder down to 5mm for the nose.

Have you got the stock or do you need the complete package?

[foxy99]

Now this is funny that you just posted right now as I'm literally just home from picking one up that a kind gentleman in Stewarton (near Kilmarnock, about 20 miles from me) made up for me.

He offered to do it when I posted on another forum and after a few emails exchanged he made it up.

I went down today with a bare head (to check that the OD passed thru the casting) and one with guides still installed (to check that the nose located ok in the guides) and it did so I got on may way.

He wouldn't accept anything for his labour either which kinda paid for the petrol I wasted getting there. Satnav took me to wrong town and added about 30 miles and a lot of stress to the journey. Ii was an hour late

Now I'm home I'm finding the nose doesn't actually fit in some NOS guides I have. They didn't come in original packaging so could have wrong ID as the tool fitted in the ones in my head ok. They could be worn right enough.

Anyway I got the vernier out and the handle is 1/2" so that must've been the size of bar he started with (it's just over 12.5mm). The OD is 9.8mm and the nose is 5.5mm which is mb a bit big as I measured the valve-stems to be 5.4mm

I'd post some pics of the tool but my camera isn't working

[Good Scrap]

Get some emery tape and you'll be able to carefully bring it down to size if you keep changing the side you lap it from it won't get far out of round. Be careful of making it too tight as the hole in the guides could tighten up when they're installed and you will struggle to get the drift out or score the guides in doing so.

[namless]

Hehe good timing! Well if its slightly larger on the nose you can drop it in a standard drill an give it a skim with emery cloth/file.

That should bring it down to the correct size.

[foxy99]

That's what I was thinking

However, last night, I was fiddling about with it and the various old and new parts I have and found that it's only the new valve-guides it won't fit into and neither would the NOS valves I have

I'm thinking new valve-guides need to be reamed-out to correct size once fitted. Am sure I read about that somewhere...

[foxy99]

Here's some pics of the tool and it fitting/not fitting into different valve-guides


new drift made from 1/2" steel bar


the business end. nose could have perhaps been longer to sit in more of the guide for max purchase and least deflection



nose fits into old guide no problem


but ain't going into new one