This is great stuff - when you do it yourself you know how well it’s been done plus have the personal satisfaction of figuring out how to do it without a line borer. Love the Mole Grip handle on the lathe on/off switch by the way! Thanks.
Interesting video, thanks for posting. Looking forward to the whole story. Ideally you would bore the centre hole in the two end mandrels before removing them from the 4 jaw chuck so you don't compromise the concentricity of the mandrel OD and the ID of the mandrels that accept the boring bar by having to re-fit to the 4 jaw...
Hi David. Thanks for watching, There was no worry of compromising the concentricity as in every case where the bushing was moved between jaws, I dialled it back in with the dial garage to with in 0.01mm for this application this was more than close enough glad you enjoyed the video and thanks for joining us in the shop
Amazing, i would like to know the tools you used to measure the line bore? Please, also is there other way around like a telescopic gauge and then a micrometer?
Question: If you lathe the aluminum bushing to be .05 mm larger than the measured bore diameter, and those bushings will be in there during the line boring process, won't that bore the area to be bored to 0.05 mm larger than they other two once you take those bushings out?
No, it won't. The key location for the line boring operation is crank main centerline. 0.05 mm is 0.002 inches, a mild crush fit. That dimension will be taken up in "tight fit" as the caps are torqued up. The crush oversize was determined at maximum "original bore- new bore" dimension (perpendicular to both axis of crank and block/cap parting line). The location is fixed by the bearing saddle in the block. If the boring centerline is on plane with the block parting face, concentric with the crank axis, only the cutting tool determines cut dimension. By dimensioning off "block bearing saddle low point", all pre-existing dimensional relationships are maintained (bearing bore- deck, -cam centerline, -rod locations), and that can only be assured by a very rigid locating method, like a crush fit on the existing bores, or a very rigid machine set up, or both
This is great stuff - when you do it yourself you know how well it’s been done plus have the personal satisfaction of figuring out how to do it without a line borer. Love the Mole Grip handle on the lathe on/off switch by the way! Thanks.
Thanks Buddy 100% bonus points for spitting the grips 👍👍
Interesting video, thanks for posting. Looking forward to the whole story. Ideally you would bore the centre hole in the two end mandrels before removing them from the 4 jaw chuck so you don't compromise the concentricity of the mandrel OD and the ID of the mandrels that accept the boring bar by having to re-fit to the 4 jaw...
Hi David. Thanks for watching, There was no worry of compromising the concentricity as in every case where the bushing was moved between jaws, I dialled it back in with the dial garage to with in 0.01mm for this application this was more than close enough glad you enjoyed the video and thanks for joining us in the shop
Just found your channel, excellent stuff
Hi Philip you are most welcome to the channel and thanks for the feedback see you around 👍
Excellent tutorial..
Glad you liked it!
Amazing, i would like to know the tools you used to measure the line bore? Please, also is there other way around like a telescopic gauge and then a micrometer?
👌 Amazing, very very interesting video
Thank you! Cheers👍
Very good
cool, onto part 2..
Thanks for the watch glad you enjoyed it
great content and cant wait to see whats to come 😁
Thank you!
Man, You really make boring videos! ;-) (kidding!!) Well Done.
Haha love it 👍
Question: If you lathe the aluminum bushing to be .05 mm larger than the measured bore diameter, and those bushings will be in there during the line boring process, won't that bore the area to be bored to 0.05 mm larger than they other two once you take those bushings out?
No, it won't. The key location for the line boring operation is crank main centerline. 0.05 mm is 0.002 inches, a mild crush fit. That dimension will be taken up in "tight fit" as the caps are torqued up.
The crush oversize was determined at maximum "original bore- new bore" dimension (perpendicular to both axis of crank and block/cap parting line). The location is fixed by the bearing saddle in the block. If the boring centerline is on plane with the block parting face, concentric with the crank axis, only the cutting tool determines cut dimension.
By dimensioning off "block bearing saddle low point", all pre-existing dimensional relationships are maintained (bearing bore- deck, -cam centerline, -rod locations), and that can only be assured by a very rigid locating method, like a crush fit on the existing bores, or a very rigid machine set up, or both
Can i have some points for spotting the Radio Spares badge on the back of the lathe? :-)
10 points to your sir
too much talking
Noted good sir
Oh dear.
Very good