Rechargable Batteries and Prop Bolts.
Posted: Fri Feb 17, 2012 8:34 pm
Hello ALL,
Just thought I would share two SAFETY RELATED items I discovered today, will thrashing away in the shop!
Cordless Drill Batteries:
I have stored my spare batteries on the top right side of my tool box unit for 7 years. At one time I had about 7 of them always thrown there in a pile, but today I was down to only one. I routed around in the top of the unit today looking for something, and then went back to work. About 15 minutes later when I went back over to my tool box I found out why I could smell something burning in the shop. I had nudged that last battery up against an old piece of safety wire that was in the back corner of the box. It nicely connected the two battery terminals and it glowed a nice red, setting the battery case and a plastic package cover for a tube of silicon on fire. It's a good thing it wasn't the end of the work day and I had locked up the shop. The batteries are now stored in a non-metallic location, all by themselves! Please do the same with yours, so your garage/shop and project aren't in jeopardy. It was the first incident in 7 years, but it could have caused a large financial impact if it had of gone undetected.
Propellor Bolts
I pulled the propellor off one of my recently acquired Rebels today and found that the bolts were tight to get out. Once out, I found that the builder had "shouldered" them due to over length that could have been adjusted with one, to one and a half more washers. There is also very clear signs of rubbing, (fretting) between the flywheel and the WarpDrive hub, showing that even though the bolts were tight, the prop and engine were not quite held tightly together. (and to think I flew this thing home!) If you are going to "cheat" and use standard 1/2" thread length AN bolts, for prop bolts (and why not when proper "prop" bolts with the 1" thread length are over $40 each and they are no different in strength than standard AN bolts contrary to popular belief), make sure you thread them in by hand until they bottom and take the measurement from the flywheel face to the underside of the head. (also feel around behind the flange bushing and get a feel for how much protrusion or recess that the bolt has, so you can recheck this after the prop bolts are torqued down). Make sure this measured dimension is LESS than the overall thickness of your prop hub, squash plate, spinner, etc. so it will tighten everything down without bottoming out. If slightly too long adjust with up to 3 washers (or a thicker squash plate). If still too long buy shorter bolts. JUST MAKE SURE THAT YOU USE ALL THE LENGTH YOU CAN THREADING INTO THE BUSHINGS, WITHOUT BOTTOMING THEM OUT. Using proper 1" thread bolts makes life easier, as they will come through the prop flange bushings enough so you can feel them protruding (sometimes as much or more than 3/8") and they still won't be bottomed out. On most prop flange bushings, using regular bolts, the bolt will either be slightly recessed or just flush with the back when bottomed out so you need to do the depth check first!
Build it and Fly it Safe,
Regards,
Wayne G. O'Shea
www.irishfield.on.ca
Just thought I would share two SAFETY RELATED items I discovered today, will thrashing away in the shop!
Cordless Drill Batteries:
I have stored my spare batteries on the top right side of my tool box unit for 7 years. At one time I had about 7 of them always thrown there in a pile, but today I was down to only one. I routed around in the top of the unit today looking for something, and then went back to work. About 15 minutes later when I went back over to my tool box I found out why I could smell something burning in the shop. I had nudged that last battery up against an old piece of safety wire that was in the back corner of the box. It nicely connected the two battery terminals and it glowed a nice red, setting the battery case and a plastic package cover for a tube of silicon on fire. It's a good thing it wasn't the end of the work day and I had locked up the shop. The batteries are now stored in a non-metallic location, all by themselves! Please do the same with yours, so your garage/shop and project aren't in jeopardy. It was the first incident in 7 years, but it could have caused a large financial impact if it had of gone undetected.
Propellor Bolts
I pulled the propellor off one of my recently acquired Rebels today and found that the bolts were tight to get out. Once out, I found that the builder had "shouldered" them due to over length that could have been adjusted with one, to one and a half more washers. There is also very clear signs of rubbing, (fretting) between the flywheel and the WarpDrive hub, showing that even though the bolts were tight, the prop and engine were not quite held tightly together. (and to think I flew this thing home!) If you are going to "cheat" and use standard 1/2" thread length AN bolts, for prop bolts (and why not when proper "prop" bolts with the 1" thread length are over $40 each and they are no different in strength than standard AN bolts contrary to popular belief), make sure you thread them in by hand until they bottom and take the measurement from the flywheel face to the underside of the head. (also feel around behind the flange bushing and get a feel for how much protrusion or recess that the bolt has, so you can recheck this after the prop bolts are torqued down). Make sure this measured dimension is LESS than the overall thickness of your prop hub, squash plate, spinner, etc. so it will tighten everything down without bottoming out. If slightly too long adjust with up to 3 washers (or a thicker squash plate). If still too long buy shorter bolts. JUST MAKE SURE THAT YOU USE ALL THE LENGTH YOU CAN THREADING INTO THE BUSHINGS, WITHOUT BOTTOMING THEM OUT. Using proper 1" thread bolts makes life easier, as they will come through the prop flange bushings enough so you can feel them protruding (sometimes as much or more than 3/8") and they still won't be bottomed out. On most prop flange bushings, using regular bolts, the bolt will either be slightly recessed or just flush with the back when bottomed out so you need to do the depth check first!
Build it and Fly it Safe,
Regards,
Wayne G. O'Shea
www.irishfield.on.ca