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squareroot
Advanced Member
Username: squareroot
Post Number: 50
Registered: 09-2013
| | Posted on Monday, September 19, 2016 - 08:54 pm: | 
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Bill says he believes we can further dis-assemble my Robert Bosch BA2 magneto if he applies heat to the bolts. Will that harm the magnet?
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giii
Member
Username: giii
Post Number: 21
Registered: 04-2010
| | Posted on Monday, September 19, 2016 - 08:59 pm: |
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There will be no permanent damage. Why not just use an impact screwdriver, the kind used with a hammer? Those fasteners will surrender quickly. |
squareroot
Senior Member
Username: squareroot
Post Number: 51
Registered: 09-2013
| | Posted on Monday, September 19, 2016 - 09:30 pm: |
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We didn't like the fit that we had between the driver bit and the bolt-slot. Slot too narrow? Will try to find a better bit. Thanks for your reply! |
david_doyle
Senior Member
Username: david_doyle
Post Number: 76
Registered: 03-2013
| | Posted on Tuesday, September 20, 2016 - 05:21 pm: |
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Having ruined a few slots on my day I now always grind a driver to fit the fastener.I'd be leary about swinging a hammer around that unless you fitt some hardwood to support the legs of the magnet.
The "right way": guys that work on electric motors used to have a special tool for this very job. a driver is supported on an arm that allows down pressure while turning. Maybe your local starter rebuilder might have one.
I'd make a good fitting bit on a HD screwdriver. I'd rest the handle end on my sternum while holding like a bear with two hands, bear down on it and have a helper turn the screwdriver using a pipe wrench. If the slots rip out then it is an hours work with the drill press and a center punch to get back to the start.
Why does it need to come apart? |
johnoxley
Senior Member
Username: johnoxley
Post Number: 161
Registered: 04-2010
| | Posted on Tuesday, September 20, 2016 - 05:51 pm: |
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First - Why do you need to remove the screws??
Second - Please do not heat or hit magnets (unless you are going to remagnetise them afterwards.
Try - A short screwdriver with hex for a spanner is gripped in a drill press - Apply pressure using drill press with maggy on wooden support on table and use spanner to undo screw. Usual fitter machinists guide - 55 minutes prep for a 5 minute job, but the result is worth it. Also need the same jig for replacing the screws.
You might be able to do this job in a 4" vice with an impact screwdriver bit (only) using the vice to apply sensible pressure while you turn bit with spanner. |
squareroot
Senior Member
Username: squareroot
Post Number: 52
Registered: 09-2013
| | Posted on Tuesday, September 20, 2016 - 08:02 pm: |
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Found a bit with good grip, and the job was accomplished quickly without requiring heat. We do have the device for recharging the magnet. Thanks to each for your suggestions. We've gotten to the condenser, and it needs replacing. Thankful that the coil might be OK. Thanks again. |
robert
Senior Member
Username: robert
Post Number: 767
Registered: 07-2003
| | Posted on Friday, September 23, 2016 - 02:46 pm: |
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Why use heat when the screw holes are not blind? Clean out the inside ends of the holes with a dental pick and put a good penetrant in there and leave it for a week or two. You'd have to do one side at a time of course. Heat with a zinc or aluminum body does not sound like a good idea to me, except maybe warming it up to maybe 200� or less in an old toaster oven just to encourage the oil to penetrate. |
squareroot
Senior Member
Username: squareroot
Post Number: 53
Registered: 09-2013
| | Posted on Sunday, September 25, 2016 - 08:14 pm: |
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You're right, Robert. The holes are not blind. Thanks for your suggestions. |
