The regulars may notice that I'm posting an hour earlier than usual. I was in the shed by 07:00 and came out at 09:00 because this morning has been hard work, not stood at the bench but crawling about, getting into funny positions and some very heavy lifting. I know, I should have shouted for help with the lift but I like to think I'm still 38 years old and can lift anything! In case you're wondering, because I know how to protect my back I haven't triggered anything. It's tired but not damaged.
The job was to finish my maintenance of the saw. The main concern was the fact that the drive unit was nodding as it drove the saw while doing a heavy cut....
This was how I left the saw last night. I've found that it's easy to disengage the saw frame from its guide bars by simply leaning the top of the unit back. Last night I sprayed the guides with penetrating oil to soften the old grease and this morning I gave them a good clean, taking all the old grease off.
While I had it opened up like this I took this pic of the top of the gearbox which is of course integral with the motor. What I had noticed was that the Allen screw you can see just above the switch was loose and when I tried it it was stripped. This was allowing the unit to move about under load. I couldn't believe that it was only held by 4 X 1/4" bolts to the main frame and so I did nothing at this point. I wanted to have a look underneath to see exactly how it was attached. You might notice that there is a plug on top of the gearbox and I assumed this was for topping the lubricant up.
Back to greasing the slide.... It just so happened that I had a tin of Molyslip grease about my person so I gave the slide and guide bars a good coat with this. Nasty black stuff but it does a good job!
This was the heavy lift.... It wasn't too bad actually because most of the weight was over the wheels. I wanted it on its end so I could examine the motor and the mount. I can't read the details on the motor accurately but as far as I can see It's Hoover 1/4hp, 2,800rpm. It is flange mounted onto the gearbox and all those nuts were tight. I still can't quite believe it but it does depend on those 1/4" bolts accessible from the top!
Once I'd finished underneath I put the saw back on its feet again. This was the hard part! After a couple of goes and a bit of grunting I got it the right way up and in a position where I could get to the offending Allen screw. I noted that the other three set screws were 1/4" Whitworth and realised that this Allen key was a replacement. When I got it out I found that it was BSF and not Whitworth. I measured the depth of the hole and found I had a bit more length so I found a 1/4" Whitworth cap screw and cut it down to size so it reached the very bottom of the drilling. I was considering tapping it for 5/16" but didn't like that idea as I didn't know how much meat there was in the casting. Remembering that a screw thread has maximum grip when the depth of thread equals mare than the diameter, I put some shaft lock on the cap screw and gave it a good but not excessive nip. It feels solid so I am calling that a cure. If it ever comes loose again I can go to Plan B! I nipped the other three set screws and called that finished. Then I took the plug out of the gearbox top and found that there was grease in the hole but when I dipped it I couldn't find a level. I don't know whether you've ever stripped a gearbox that is grease lubricated but over the years the grease hardens and gets squeezed out of the teeth, most of it stuck to the outside casing so I filled a grease gun with ordinary Castrol Grease. It had a fine nozzle so I could poke the end right in the hole and pumped a gun full of grease in, following that up with some SAE40 oil to encourage the grease to flow. I can't see that getting me into any trouble!
I had noticed that the thread on the cable protector wasn't a good fit in the switch so before Ian gets on to me I made sure it was secure by strapping it with insulting tape.... Notice that it's a proper on/off switch. When it's running the outside edge of the red centre pops up and is the emergency stop. The automatic cut out actuated by the depth of the saw doesn't actually switch the machine off, it breaks the circuit to the motor, when the saw stops you have to depress the red outer ring until it clicks to completely switch off.
Close of play. I think that apart from the normal wear in the crank pin and the big end it's as good now as when it was new. Better really because that locking screw on the strut was a bit tatty. I didn't bother trying another cut, that will come soon enough. I'm sure it will be OK. Dave did me proud, it's a heavy well built bit of kit that does a good job.
Now all I need is a small Adept bench shaper for slotting pulley wheels..... Are you listening Lads?