Sent 05 Ex to RF Powerboats
02-24-2012 | 12:56 PM
#612
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From: KC, MO
Boy, this thread got off track in a hurry. Let me get it back headed in the right direction.
We have all of the machine work done. We are in the process of preping everything before assembly. Every hole in the block has been bottom tapped (since it has never been done before) This insures us that all of the threads are good and clean and they go all the way to the bottom of the hole. When the block is made, they use a starting tap to thread the holes. The first 5-6 threads are chamfered and are not full threads so the tap will cut easier. You end up with a 1" deep hole that only has about 5/8" of usable thread. We cut those last few threads with a bottom tap that has only 1 chamfered thread. That way the entire hole is usable for more thread engagement.
We also go through the entire block and deburr it and remove any and all sharp edges. There are tons of pieces of slag and casting flash that are hanging off of the block. We don't want any of those to go through the engine. There was one piece that was hitting the crank counterweight and preventing it from turning over. All of the sharp edges left after machining are full of tiny little burrs. We don't want any of that material left in there to do any damage. We also don't want to get cut by them since they are like razors. Lastly, God forbid there should be a failure, but a rounded corner is harder to crack than a sharp one. It could potentially help to save the block. It takes us about 2 days per block to do all of this prep work. It's very time consuming and you really don't get paid for it, but I wouldn't even consider not doing it.
Now that the grinding and tapping are done, we washed them thoroughly (the third time). Now we can start fitting bearings and gapping rings.
I will post some pics as soon as I can. My laptop took a dump, so we are trying to recover all of the data. I have some pics on there so hopefully I can get them. I will take more as the work continues.
Eddie
We have all of the machine work done. We are in the process of preping everything before assembly. Every hole in the block has been bottom tapped (since it has never been done before) This insures us that all of the threads are good and clean and they go all the way to the bottom of the hole. When the block is made, they use a starting tap to thread the holes. The first 5-6 threads are chamfered and are not full threads so the tap will cut easier. You end up with a 1" deep hole that only has about 5/8" of usable thread. We cut those last few threads with a bottom tap that has only 1 chamfered thread. That way the entire hole is usable for more thread engagement.
We also go through the entire block and deburr it and remove any and all sharp edges. There are tons of pieces of slag and casting flash that are hanging off of the block. We don't want any of those to go through the engine. There was one piece that was hitting the crank counterweight and preventing it from turning over. All of the sharp edges left after machining are full of tiny little burrs. We don't want any of that material left in there to do any damage. We also don't want to get cut by them since they are like razors. Lastly, God forbid there should be a failure, but a rounded corner is harder to crack than a sharp one. It could potentially help to save the block. It takes us about 2 days per block to do all of this prep work. It's very time consuming and you really don't get paid for it, but I wouldn't even consider not doing it.
Now that the grinding and tapping are done, we washed them thoroughly (the third time). Now we can start fitting bearings and gapping rings.
I will post some pics as soon as I can. My laptop took a dump, so we are trying to recover all of the data. I have some pics on there so hopefully I can get them. I will take more as the work continues.
Eddie
03-01-2012 | 03:39 PM
#615
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From: KC, MO
03-01-2012 | 05:11 PM
#616
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From: Galveston,TX
03-01-2012 | 06:01 PM
#617
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From: Tennessee
