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2021 POTD Thread Archive
- Thread starter Gaffer
- Start date
- Joined
- Aug 22, 2012
- Messages
- 4,295
Made a clamp tool to hold a section of a die to hopefully make a thread chaser.
The front bolt tightens the clamp, the sides prevent the die bit from turning or sliding sideways and the rear bolt cantilevers the clap upwatrd exerting more pressure on the die bit.
Here is a test cut in plastic of a four start M1 thread, I've stopped one pass so you can see the four simultaneous threads.
It seems good, smooth, no rough bits but I dont yet have the nut to test it.
One change I should make is to re-shape the bit to cant the thread angle more in keeping with the M4 thread angle.
Its too shallow at the moment but did still work well.
The front bolt tightens the clamp, the sides prevent the die bit from turning or sliding sideways and the rear bolt cantilevers the clap upwatrd exerting more pressure on the die bit.
Here is a test cut in plastic of a four start M1 thread, I've stopped one pass so you can see the four simultaneous threads.
It seems good, smooth, no rough bits but I dont yet have the nut to test it.
One change I should make is to re-shape the bit to cant the thread angle more in keeping with the M4 thread angle.
Its too shallow at the moment but did still work well.
- Joined
- Aug 22, 2012
- Messages
- 4,295
quick update, it worked fine on aluminium but not on stainless.
I will see what the new angles do when I get that done.
- Joined
- Sep 28, 2013
- Messages
- 4,403
made a new countershaft and motor pulley for my SB9, both to reduce motor pulley slip (J6 to J8 belt) and reduce countershaft pulley speed
and static balanced on my ghetto rig
works a treat, no vibration, spindle speeds are down ~20% and slip is reduced a bit though I still need to use backgears for low speed/ high load cuts. Onto the next project!
and static balanced on my ghetto rig
works a treat, no vibration, spindle speeds are down ~20% and slip is reduced a bit though I still need to use backgears for low speed/ high load cuts. Onto the next project!
- Joined
- Nov 25, 2015
- Messages
- 10,045
Looks great, but why would you want to reduce the speed? I'm probably late to the game here.
- Joined
- Sep 28, 2013
- Messages
- 4,403
good question - I'm running a treadmill motor and want to keep the max spindle speed to ~1500rpm. WIth what I had intended to be the middle pulley ratio (about 1:1) the top spindle speed would be nearly 2000rpm, which is both way too fast for comfort and would make the large spindle pulley kinda pointless. So slowing down the countershaft speed will help get me closer to the range I want and now that it's done I can calculate the countershaft step pulley diameters and start making them 
- Joined
- Jul 14, 2017
- Messages
- 2,459
Well i've been gone for half a month, i had a emergency trip to Athens, Greece i made the trip in my brothers Ford. Which was a mistake, it managed to burn thru 7 liters of engine oil in 1500 Km. But just as i come back i could see white elephant no: 2 was waiting for me in the small garage. My brother managed to drop the engine out of it, in the process broken a coolant line and left it to drain coolant in the inspection pit for days. In the picture the engine was future down i raised it immediately because only thing holding it was the battery positive lead. The repair was simple, i only threaded the mount with a bigger tap drill it deeper also, reinstalled everything new hose ( 20 year old one but not broken) new coolant and it was back to use. I'm not sure how or where this car broke but my brother maned to buy one more car a GM now.
- Joined
- Nov 25, 2015
- Messages
- 10,045
I'd be looking for a new brother
- Joined
- Jul 14, 2017
- Messages
- 2,459
It's the roads and the loose nut behind the wheel, he jump railroad tracks a bit fast and when he landed white elephant could not hold its belly. I'm more afraid of the GM (general motors) he just bought, they brake all the time.I'd be looking for a new brother
- Joined
- Sep 5, 2013
- Messages
- 3,936
Some days a guy just gets lucky….
This is what was left of a flat-head #7 screw seized inside the barrel of the crank lobe after I torqued the head off trying to horse it out. Eyeballed the first hole in with a #54 drill then pulled it out with a #51
Some days a guy just gets lucky…
This is what was left of a flat-head #7 screw seized inside the barrel of the crank lobe after I torqued the head off trying to horse it out. Eyeballed the first hole in with a #54 drill then pulled it out with a #51
Some days a guy just gets lucky…
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