Hi Tony
Is the back improving now I hope the meds are working OK for you. I dont know if you are checking the site but this is where I am up to, facing the .08 surplus off the cam was a bit of a disaster I managed to turn the gear location dia .02 u.size must learn how to read a mic.I thought of a few options but decided to remake it as it was a nice job to do originally & would let me get more use from the milling fix. I made it exactly the same except the marking out which I did similar to the crank image below, grind a knife edge on a piece of round HSS & mount in the spindle grip cam blank in dividing head chuck & set in freewheel mode & use the DRO to space out markings lot easier than height gauge.The spare cam will be useful for a trial heat treatment if necessary. Started on the crank faced both ends & mounted in vee block to centre both ends in mill using DRO I remember doing an actuator gearbox many years ago where the gear centres were lapped before grinding between centres so I lapped these with an old dead centre & fine lapping paste it cannt do any harm, then turned down to ¾ dia from 1.1/4 which was the size in the kit. I have not used this material before it seems very similar to S1 mild steel picks up & tears very easily when turned. I roughed main journals plunge cutting with Iscar self grip p/off tool & 3mm neutral insert tried most of speeds available for this, 500 rpm seemed to work best when I tried this on the other journals it would not cut just tried to push away from the job probably due to interrupted cut I ground up 3mm wide HSS groove tool & used this 1 pass down centre then 1 either side to about .4 dia which is where I am at now, 315 rpm seemed best, worked OK. The tool chattered a lot as can be seen from the image due to interrupted cut I think it will improve when down to a full dia. It needed a regrind on top face about 4 times per plunge cut this was indicated when the swarf changed from fine needles to lumps of swarf. I did 1 journal per day as I lose patience easily, when finished I released pressure on the tailstock for the night & noticed when I tightened it up for the 2nd journal a very slight pressure caused the first journal to start to collapse I dont know what it will be like when they are turned to size will have to make some small turning tools maybe modify 2mm insert p/off tools. Checked between centres when finished & got 0.012 TIR not bad considering the amount of material hacked out & it not being a very symmetrical shape, will set on 2 vee blocks & use press to straighten before final turning .Going on hols at weekend so will check if it moves while I am away maybe I should leave it outside to weather like a casting!
Hope you are soon back in shop making swarf with a pain free back.
Is the back improving now I hope the meds are working OK for you. I dont know if you are checking the site but this is where I am up to, facing the .08 surplus off the cam was a bit of a disaster I managed to turn the gear location dia .02 u.size must learn how to read a mic.I thought of a few options but decided to remake it as it was a nice job to do originally & would let me get more use from the milling fix. I made it exactly the same except the marking out which I did similar to the crank image below, grind a knife edge on a piece of round HSS & mount in the spindle grip cam blank in dividing head chuck & set in freewheel mode & use the DRO to space out markings lot easier than height gauge.The spare cam will be useful for a trial heat treatment if necessary. Started on the crank faced both ends & mounted in vee block to centre both ends in mill using DRO I remember doing an actuator gearbox many years ago where the gear centres were lapped before grinding between centres so I lapped these with an old dead centre & fine lapping paste it cannt do any harm, then turned down to ¾ dia from 1.1/4 which was the size in the kit. I have not used this material before it seems very similar to S1 mild steel picks up & tears very easily when turned. I roughed main journals plunge cutting with Iscar self grip p/off tool & 3mm neutral insert tried most of speeds available for this, 500 rpm seemed to work best when I tried this on the other journals it would not cut just tried to push away from the job probably due to interrupted cut I ground up 3mm wide HSS groove tool & used this 1 pass down centre then 1 either side to about .4 dia which is where I am at now, 315 rpm seemed best, worked OK. The tool chattered a lot as can be seen from the image due to interrupted cut I think it will improve when down to a full dia. It needed a regrind on top face about 4 times per plunge cut this was indicated when the swarf changed from fine needles to lumps of swarf. I did 1 journal per day as I lose patience easily, when finished I released pressure on the tailstock for the night & noticed when I tightened it up for the 2nd journal a very slight pressure caused the first journal to start to collapse I dont know what it will be like when they are turned to size will have to make some small turning tools maybe modify 2mm insert p/off tools. Checked between centres when finished & got 0.012 TIR not bad considering the amount of material hacked out & it not being a very symmetrical shape, will set on 2 vee blocks & use press to straighten before final turning .Going on hols at weekend so will check if it moves while I am away maybe I should leave it outside to weather like a casting!
Hope you are soon back in shop making swarf with a pain free back.
