A very slow Fobco Star refurbishment

[skippy75]

Hi, after having the star for 10 years it’s finally forced me to do a refurb because some awful run out has started.

I’ve got the motor pulley off but I cannot get the spindle pulley to budge. It’s soaking with penetrating oil and I’ve had a three prong gear puller on it cranked as hard as I dare but there’s no movement at all.

I’ve taken the grub screws out and looked for any sneaky second screws.

I haven’t tried any heat yet but im really worried about cracking this pulley with the amount of force it’s resisting.

Does anyone have any advice?

 

[flh801978]

I would get a blowtorch on the pulley as hot as you can get it
Make sure that your socket is properly down the hole and resting on the spigot..
They normally come off easily
Ian

 

[skippy75]

I would get a blowtorch on the pulley as hot as you can get it
Make sure that your socket is properly down the hole and resting on the spigot..
They normally come off easily
Ian

I’ve got the quill wound down with a socket under the gear puller so that it’s pushing on the sleeve inside the pulley right now. You think I’m better pushing against the top of the spindle down the hole?

 

[flh801978]

No you definately need to push against the sleeve/spigot

Ian

 

[flh801978]

How long is that socket that you are using? as i remember the spigot is about 30mm down the hole

 

[skippy75]

How long is that socket that you are using? as i remember the spigot is about 30mm down the hole

I’ve been pushing against the slightly raised centre of the pulley. With the spindle wound all the way down there’s nothing else down the tube to push against until you hit the top of the spindle. I assumed the shaft was just higher on mine.

 

[Fitzroy]

Following with interest as I've tried to get the top pulley off on mine before and given up. I think you're doing it right based on this drawing.

 

[skippy75]

Following with interest as I've tried to get the top pulley off on mine before and given up. I think you're doing it right based on this drawing.

I bought that guide from Tony so long ago I actually forgot to look!

I’m going to keep bathing it in plusgas for a few days and then give it another go with some heat and enjoy the fumes in my tiny shop.

 

[Henniep]

I bought that guide from Tony so long ago I actually forgot to look!

I’m going to keep bathing it in plusgas for a few days and then give it another go with some heat and enjoy the fumes in my tiny shop.

Forgive if this is obvious. Careful of overheating, or protracted heating as the heat may migrate to the shaft and expand it as well.

 

[clogs]

Henniep
it's an ally pulley...they will always expand more than the steel shaft regardless of the temp.....
Steel on steel is works as u describe....
ally to steel carrosion would be the biggest prob here I guess..those two metals dont like each other....

Skippy, if u dont need to take to take it off just paint around it.....could save a lot of heart ache......

 

[deema]

I’ve not worked on one of these drills, but a lot of other machines. I’m guessing the grub screws had cone ends, or in other words pointed. Often these will have been over tightened and caused a burr / deformed the metal around it. If too slack the pulley can have spun and the grub screw chewed up the shaft. Either scenario makes getting the pulley off the shaft very very difficult.
The pulley looks to be cast iron, heat is you friend, most people don’t heat them up enough. If it’s aluminium be very careful not to melt it!

 

[flh801978]

Clogs
surely you can see that its steel....

 

[skippy75]

Success!

With safety goggles firmly on my face and fear in my heart I put the gear puller back using the socket to put the force onto that central tube. I applied some force with a wrench and started tapping the top of the central screw on the bearing puller with a hammer. I kept switching between tapping and tightening as it fought me all the way off.

Didn’t have to use any heat in the end which is a bonus.

 

[skippy75]

Forgive if this is obvious. Careful of overheating, or protracted heating as the heat may migrate to the shaft and expand it as well.

A warning is always appreciated however obvious it might seem. I do lots of stupid things so it’s good to be reminded. Thankfully I didn’t need any heat in the end.

As I’ve only got a crappy blow torch I wasn’t sure how I’d go getting enough heat into the pulley before the shaft started warming up. Plus the previous owner liked grease a lot so I wasnt looking forward to that.

Henniep
it's an ally pulley...they will always expand more than the steel shaft regardless of the temp.....
Steel on steel is works as u describe....
ally to steel carrosion would be the biggest prob here I guess..those two metals dont like each other....

Skippy, if u dont need to take to take it off just paint around it.....could save a lot of heart ache......

They are cast iron in this case. I suspect it’s just never been taken off since manufacture.

I have to change out the bearings as the run out was so bad you could see it with the naked eye. It was drilling oval holes. Complete disassembly is going to be unavoidable unfortunately.

I’ve not worked on one of these drills, but a lot of other machines. I’m guessing the grub screws had cone ends, or in other words pointed. Often these will have been over tightened and caused a burr / deformed the metal around it. If too slack the pulley can have spun and the grub screw chewed up the shaft. Either scenario makes getting the pulley off the shaft very very difficult.
The pulley looks to be cast iron, heat is you friend, most people don’t heat them up enough. If it’s aluminium be very careful not to melt it!

You can see where the grub screws have bitten into the steel so I suspect that was part of the issue.

 

[Fitzroy]

I have to change out the bearings as the run out was so bad you could see it with the naked eye. It was drilling oval holes. Complete disassembly is going to be unavoidable unfortunately.

Great that you got it off. Can the bearings on the pully assembly result in runout issues? I'd assumed it was only the quill and bearnings inside the quill that impact runout. I have a little runout in my Fobco that has yet to annoy me enough to warrent a rebiuld.

More annoying is the vibration when there is no load on the drill. Reading posts it looks like this is to do with the preload on the angular contact bearings in the quill, which I may investigate this weekend.

Fitz.

 

[skippy75]

Great that you got it off. Can the bearings on the pully assembly result in runout issues? I'd assumed it was only the quill and bearnings inside the quill that impact runout. I have a little runout in my Fobco that has yet to annoy me enough to warrent a rebiuld.

More annoying is the vibration when there is no load on the drill. Reading posts it looks like this is to do with the preload on the angular contact bearings in the quill, which I may investigate this weekend.

Fitz.

Im just an idiot working it out as I go along to be honest so I have no idea. My plan is to take everything apart, check for wear the best I can and then replace all the bearings. There’s a strong chance I will end up with less money and a drill that’s worse.

There was a huge amount of wobble in the front pulley before I got it off which I can’t imagine is normal.

 

[Fitzroy]

Im just an silly person working it out as I go along to be honest so I have no idea. My plan is to take everything apart, check for wear the best I can and then replace all the bearings. There’s a strong chance I will end up with less money and a drill that’s worse.

There was a huge amount of wobble in the front pulley before I got it off which I can’t imagine is normal.

We sound similar, and if you’re pulling it all apart may as well do it properly. It was your post that made me think about my drill and to go and read around the problem, there are some great refurb threads on the site and over on the model engineer and mug welding forums. It was those posts that got me thinking about what causes runout and my vibration issue.

 

[skippy75]

We sound similar, and if you’re pulling it all apart may as well do it properly. It was your post that made me think about my drill and to go and read around the problem, there are some great refurb threads on the site and over on the model engineer and mug welding forums. It was those posts that got me thinking about what causes runout and my vibration issue.

It’s nice that it’s a popular drill. Plenty of references out there and even spare parts.

Will be interesting to hear what you find with yours. I suspect you’ll get it done faster than me!

 

[skippy75]

I have begun degreasing the parts I’ve taken off so I can oil them and pop them in labelled bags. For the moment I’m just using elbow grease spray and an old toothbrush followed by a rinse and a squirt of wd40.

I’m reached the point where I have to decide what kind of restoration I’m doing. I think I’m going to try and keep the patina where possible and repaint as nicely as I can. She’s old and I want to respect that rather than making everything shiny.

The other big question is cream or turquoise? I love the turquoise but how much do I care about originality here? It’s into meaning of life now and 10 years of thinking about it hasn’t made me any clearer.

I bought a special jar for my grease scrapings so I can dispose of it responsibly.

 

[skippy75]

I underestimated the quill spring…. Luckily only a relatively minor cut on my thumb.