Wadkin AGS10 bush replacement

[Megaweasel]

Hi everyone,

So after getting the motor sorted for my AGS10 (single phase TEC, 1.5KW) I stripped the machine and got the spindle machined true with a new nut for the pulley end, and then stripped the machine down for sand blasting. I guess in my head I didn’t really worry about the bronze bushes as I kinda thought I’d replace them anyway, and the guy doing the blasting said he’d stick a couple of washers with a bolt/rod through to protect them - however, he clearly didn’t do this and they are now as rough as. - well - use your own preferred analogy… He also left the parts outside where he did his blasting for a couple of days through the rain, meaning the bits that I wrapped to protect them have a nice coating of rust now..

anyway - so it looks like I need to replace the bushes and I realise I have no idea what I’m doing here. Q1 - how do I remove them, Q2 - how do I size new ones (in case they need to be different than the sizes in the manual) and what are they for the purposes of ordering (oilite or something else?), and Q3 - how do I get the new ones fitted?

I have two in the main casting and one in the end of the rise-and-fall shaft.

cheers for any help you can offer..

Chris

 

[ChaiLatte]

Q1 - how do I remove them, Q2 - how do I size new ones (in case they need to be different than the sizes in the manual) and what are they for the purposes of ordering (oilite or something else?), and Q3 - how do I get the new ones fitted?

1. Find a thick washer that is larger in diameter than the bush. Put washer on bolt. Put nut on bolt. Tighten. Wrap insulation tape around threads on bolt. Grip shaft of bolt in drillpress and switch on. Apply file until washer OD is a smidge under bush OD.

Find socket that is larger a/f than bush. Remove bolt from drillpress and remove insulation tape. Poke through bushy hole and through socket. Add washer that is larger OD than square in socket. Add nut. Tighten. The bush will pull itself into the socket.

3. Installation is the reverse of removal and you do not need the socket.

2. Bushes are sized by OD, ID and width. George Lodge has a good selection of imperial and metric oilite.

42. Threaded rod looks like a very long headless bolt.

 

[Megaweasel]

Cheers! Sounds like something I can achieve

 

[Fergie 307]

I hope your grit blaster put something in the threaded holes to protect them, otherwise you will have fun and games getting all the grit out.

 

[Megaweasel]

nope - he did not. I guess my fault for assuming he would take proper care

I'll try blasting them with the airline and after painting runs a tap through them I guess.

 

[Inspector]

No help now but the type of abrasive blasting done has a great influence on the damage it can inflict on the parts. There are a number of blasting media available but most places use cheap and rough which don't matter a lot when blasting cast iron fences and bulldozer blades. We used to have aircraft slat tracks sent out for titanium cadmium plating for corrosion resistance and then painted. Sometimes they would get the masking wrong and some of the paint had to be removed. They used a plastic bead to blast of the unwanted paint and it did no damage to the soft plating. What I am trying to say is to look for place that have gentler blasting media options like soda, walnut shell, corn cob, dry ice, plastic bead, glass bead etc. Also don't trust them to protect dimensionally critical surfaces. Mask or plug them yourself or get them to understand they need to.

Pete

 

[Megaweasel]

No help now but the type of abrasive blasting done has a great influence on the damage it can inflict on the parts. There are a number of blasting media available but most places use cheap and rough which don't matter a lot when blasting cast iron fences and bulldozer blades. We used to have aircraft slat tracks sent out for titanium cadmium plating for corrosion resistance and then painted. Sometimes they would get the masking wrong and some of the paint had to be removed. They used a plastic bead to blast of the unwanted paint and it did no damage to the soft plating. What I am trying to say is to look for place that have gentler blasting media options like soda, walnut shell, corn cob, dry ice, plastic bead, glass bead etc. Also don't trust them to protect dimensionally critical surfaces. Mask or plug them yourself or get them to understand they need to.

Pete

Fair points - having gone over a few parts today, it doesn’t look too bad - looks like a very fine ‘sand’ was used and mating surfaces like ones on the main tilting assembly seem to have come back up with only the lightest of sanding. I’ll blast it with air and tentatively try a few bolts.

It’s been said before in a few places, but the quality of the castings is really pretty rubbish. In the raw you can see the soft of fettling the Wadkin did - it ain’t too pretty. Didn’t notice it particularly under its old paint so hopefully will be the same once its painted up. I could spend hours fettling it but I’m not sure it will make much difference to how it works.

good news is I’ve got the spindle back from a local engiineering firm who have skimmed it for me - its now straight and true And looking good.

 

[Fergie 307]

nope - he did not. I guess my fault for assuming he would take proper care

I'll try blasting them with the airline and after painting runs a tap through them I guess.

make sure you wear safety glasses. Best way I have found is to use an airline with a tip fine enough to be inserted all the way to the bottom of the hole then pressure on and gradually withdraw it. Any grit will come out with some force, so don't get it in your eyes. And I wouldn't use a tap, unless it's an old one. Any grit will blunt it surprisingly quickly. I would get a bolt of the same size and file or grind grooves down it, like a tap. Use this to get the worst of the crud out, then a tap once it's fairly clean. One commonly used media is copper slag, looks like tiny bits of black glass. Horrible stuff.