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Holt Engine (I hope)
- Thread starter f350ca
- Start date
- Joined
- Dec 15, 2018
- Messages
- 785
Busy with other projects but stole some time to make the cam shaft. One piece at a time lol
Used a parting tool to layout the lobes and bearing surfaces down the cam. No DRO on this lathe so spaced it off with a 2 inch dial indicator.
Then cut the sides and back of each lobe on the mill. Need to round over the top of the lobe, will do this with a file and radius gauge.
Thanks for looking.
Greg
Used a parting tool to layout the lobes and bearing surfaces down the cam. No DRO on this lathe so spaced it off with a 2 inch dial indicator.
Then cut the sides and back of each lobe on the mill. Need to round over the top of the lobe, will do this with a file and radius gauge.
Thanks for looking.
Greg
- Joined
- Dec 15, 2018
- Messages
- 785
Thanks for the likes guys.
Its an addictive project, have to set it aside from time to time to get other projects and other peoples work done. lol
Thanks George, its no where near your quality of work. Have a couple of questions on the build, will be sending you an e-mail at some point if you don't mind.
Greg
Its an addictive project, have to set it aside from time to time to get other projects and other peoples work done. lol
Thanks George, its no where near your quality of work. Have a couple of questions on the build, will be sending you an e-mail at some point if you don't mind.
Greg
- Joined
- Sep 5, 2013
- Messages
- 3,207
I love the looks of those gears! I have to ask, what’s the advantage of using the multiple-tooth hob versus the regular single-tip gear cutter? Speed in that it allows the teeth to be cut full-depth in one pass, or..?
-frank
-frank
- Joined
- Dec 15, 2018
- Messages
- 785
Thanks Frank.
The single tip cutters come in a set of 8 shapes to cut from a rack to a small gear. Each cutter will apparently approximate the tooth on a range of number of teeth.
A proper spiralled hob while cutting the rotating blank will cut the true form on a gear of any number of teeth,
My approximation of a hob is the form of a rack cut on a cylinder. The centre tooth lines up to the centre line of the blank and cuts that valley (?) while the cutters above and below relieve the adjacent gear teeth to approximate their shape to roll in and out of the gear they mesh with.
When cutting 32 tooth gears here the centre cutter tooth goes full depth and two teeth above and below were removing metal to form the tooth shape.
To be true full, I couldn't find a Chinese set of 32 DP cutters and couldn't afford domestic ones so we came up with this idea. lol
On small gears like this I'd go full depth with a regular cutter so no time savings. Especially in bronze.
Greg
The single tip cutters come in a set of 8 shapes to cut from a rack to a small gear. Each cutter will apparently approximate the tooth on a range of number of teeth.
A proper spiralled hob while cutting the rotating blank will cut the true form on a gear of any number of teeth,
My approximation of a hob is the form of a rack cut on a cylinder. The centre tooth lines up to the centre line of the blank and cuts that valley (?) while the cutters above and below relieve the adjacent gear teeth to approximate their shape to roll in and out of the gear they mesh with.
When cutting 32 tooth gears here the centre cutter tooth goes full depth and two teeth above and below were removing metal to form the tooth shape.
To be true full, I couldn't find a Chinese set of 32 DP cutters and couldn't afford domestic ones so we came up with this idea. lol
On small gears like this I'd go full depth with a regular cutter so no time savings. Especially in bronze.
Greg
- Joined
- Dec 15, 2018
- Messages
- 785
A little more progress.
Have made the rocker arms, mounts and rocker shafts?
Made the rocker arms from a bar of bronze I whittled out of a big bushing. Could do the critical dimensions with the mill them a lot of hand work to get the form.
While I was polishing the rocker arms the buffing wheel caught one and threw it into the great expanse of my messy shop. With the prospect of spending hours to remake one the search began. I spent a hour on my hands and knees under the plasma table, under the break that had a large amount of stock piled under it, under the compressor, the bench, the welders etc. Finally called my son Charlie out to help. the search continued, He finally emptied an over stuffed shelf in the overhead cabinet above the break to find it at the very back. lol Switched to a little buffing wheel on a dremel to finish. lol
I need to get collets in 64ths, had to set up the indexing head and 3 jaw to put the hex on the rocker arms.
On a side note, building a frame, setting up a fuel system and wiring this generator for someone took me away from the real project, the HOLT.
Thats my new apprentice, she was really helpful carrying away wire and tools the day I set up the breaker panel. We have an ongoing battle, she seams to think sparks from the grinder and welder have to be caught and barked at.
Thanks for looking
Greg
Have made the rocker arms, mounts and rocker shafts?
Made the rocker arms from a bar of bronze I whittled out of a big bushing. Could do the critical dimensions with the mill them a lot of hand work to get the form.
While I was polishing the rocker arms the buffing wheel caught one and threw it into the great expanse of my messy shop. With the prospect of spending hours to remake one the search began. I spent a hour on my hands and knees under the plasma table, under the break that had a large amount of stock piled under it, under the compressor, the bench, the welders etc. Finally called my son Charlie out to help. the search continued, He finally emptied an over stuffed shelf in the overhead cabinet above the break to find it at the very back. lol Switched to a little buffing wheel on a dremel to finish. lol
I need to get collets in 64ths, had to set up the indexing head and 3 jaw to put the hex on the rocker arms.
On a side note, building a frame, setting up a fuel system and wiring this generator for someone took me away from the real project, the HOLT.
Thats my new apprentice, she was really helpful carrying away wire and tools the day I set up the breaker panel. We have an ongoing battle, she seams to think sparks from the grinder and welder have to be caught and barked at.
Thanks for looking
Greg