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2019 POTD Thread Archive
- Thread starter GoceKU
- Start date
- Joined
- May 3, 2017
- Messages
- 2,003
Nice shadow.
Continuing on with my broom project from here (https://www.hobby-machinist.com/thr...you-make-in-your-shop-today.67833/post-647777), today was a one step forward, two steps back day.
I went out and bought bolts for the bracket I made yesterday, and a new belt for running the hydraulic system (old belt was worn out), and a belt to go from the engine to the jackshaft on that bracket, which went ok, and then bolted on the front end I made earlier, and was mounting the broom to measure how long a belt I would need for that, and saw the sticker that indicates what model the "adapter" I bought with the broom is (the broom head has a model&serial number, and then you buy a tractor-specific adapter to mate it to the tractor).
I had bought the setup used, with minimal info about it, and so found several adapter manuals that looked correct for the parts I had. Those manuals showed that the belt from the jackshaft to the broom needed to be twisted/reversed to get the right broom rotation. But, I went and downloaded the manual with that model number I found, and it doesn't need the belt twisted/reversed. And then I double-checked both the engine rotation and rotating the broom pulley to verify broom rotation, and it definitely doesn't need to be reversed.
Finally, the distance from the jackshaft on the rear-mounted bracket I made, to the pulley on the broom, indicates I would need a belt around 112" or so, which are more difficult to get in high-power belts (vs fraction hp belts).
Unfortunately, I cut out the front mount for the jackshaft to use it as part of the rear mount (circled in red in the pic below), so I cut another length of bar, drilled the hole in the middle, and welded it in place. It was a little easier than the first time, as I could line it up with the stubs from the previous piece, and the jackshaft installed on the new mount lines up properly with the pulley on the engine.
Tomorrow, I have to buy some more belts that should be readily available (46" and 63" or so), and then work on making a lever for raising/lowering the brush. Then I need to figure out how much force needs to be put on that lever to raise the broom, so I can then calculate how strong of an actuator I would need to buy to do it.
Once I can raise/lower the broom, I can test how the brush works, and see if I need to modify the jackshaft pulleys, as the one to the broom doesn't line up too well with the broom's pulley.
Oh, I also noticed that the corners of the bracket that the broom mounts to (circled in red in the pic below, which also shows the mount for the jackshaft was cut out), interferes with the rotation of the caster wheels. I'll probably cut off the corners, then add some more braces to the middle, as the broom both weights a decent amount (about 200-250 lbs or so) and all that weight is carried by that bracket when the broom is lifted, as well as handling the forces from shoving that weight around while using the broom.
I went out and bought bolts for the bracket I made yesterday, and a new belt for running the hydraulic system (old belt was worn out), and a belt to go from the engine to the jackshaft on that bracket, which went ok, and then bolted on the front end I made earlier, and was mounting the broom to measure how long a belt I would need for that, and saw the sticker that indicates what model the "adapter" I bought with the broom is (the broom head has a model&serial number, and then you buy a tractor-specific adapter to mate it to the tractor).
I had bought the setup used, with minimal info about it, and so found several adapter manuals that looked correct for the parts I had. Those manuals showed that the belt from the jackshaft to the broom needed to be twisted/reversed to get the right broom rotation. But, I went and downloaded the manual with that model number I found, and it doesn't need the belt twisted/reversed. And then I double-checked both the engine rotation and rotating the broom pulley to verify broom rotation, and it definitely doesn't need to be reversed.
Finally, the distance from the jackshaft on the rear-mounted bracket I made, to the pulley on the broom, indicates I would need a belt around 112" or so, which are more difficult to get in high-power belts (vs fraction hp belts).
Unfortunately, I cut out the front mount for the jackshaft to use it as part of the rear mount (circled in red in the pic below), so I cut another length of bar, drilled the hole in the middle, and welded it in place. It was a little easier than the first time, as I could line it up with the stubs from the previous piece, and the jackshaft installed on the new mount lines up properly with the pulley on the engine.
Tomorrow, I have to buy some more belts that should be readily available (46" and 63" or so), and then work on making a lever for raising/lowering the brush. Then I need to figure out how much force needs to be put on that lever to raise the broom, so I can then calculate how strong of an actuator I would need to buy to do it.
Once I can raise/lower the broom, I can test how the brush works, and see if I need to modify the jackshaft pulleys, as the one to the broom doesn't line up too well with the broom's pulley.
Oh, I also noticed that the corners of the bracket that the broom mounts to (circled in red in the pic below, which also shows the mount for the jackshaft was cut out), interferes with the rotation of the caster wheels. I'll probably cut off the corners, then add some more braces to the middle, as the broom both weights a decent amount (about 200-250 lbs or so) and all that weight is carried by that bracket when the broom is lifted, as well as handling the forces from shoving that weight around while using the broom.
Last edited:
- Joined
- Oct 18, 2016
- Messages
- 2,872
Built A Fixture To Index The Spindle On The Lathe
Owners of old Logans know how small the dials on the cross feed are and how hard they are to read. I plan on making
a set of bigger dials, but to do that I need to index the spindle to inscribe the marks. So I built a fixture.
First, an old but unworn 100 tooth gear was sourced on eBay. In order to securely lock the gear I need a solid mounting
point for the fixture. By removing the lathe's reverse gear assembly, I was able use it's mounting hole and the bolts that secure it
to the headstock. A 6061 spindle with an offset flange was turned and cross drilled for a 1/4 inch steel pin. The end of the pin
was ground to fit between the teeth on the gear, and a set screw provided to secure it. A spacer was turned and pressed
into the gear to adapt it to the aft end of the spindle, and a brass plug with an MT3 taper was turned to fit into the opposite
end. All those parts are held together with a length of all thread acting as a drawbar. My 4 jaw chuck can
be mounted right over the top of this stuff, and I was pleased to find that the gear locks up solidly when it's all in place.
Loosening the set screw is all it takes to move the gear to the next tooth. Now all I have to do is make the part!
Owners of old Logans know how small the dials on the cross feed are and how hard they are to read. I plan on making
a set of bigger dials, but to do that I need to index the spindle to inscribe the marks. So I built a fixture.
First, an old but unworn 100 tooth gear was sourced on eBay. In order to securely lock the gear I need a solid mounting
point for the fixture. By removing the lathe's reverse gear assembly, I was able use it's mounting hole and the bolts that secure it
to the headstock. A 6061 spindle with an offset flange was turned and cross drilled for a 1/4 inch steel pin. The end of the pin
was ground to fit between the teeth on the gear, and a set screw provided to secure it. A spacer was turned and pressed
into the gear to adapt it to the aft end of the spindle, and a brass plug with an MT3 taper was turned to fit into the opposite
end. All those parts are held together with a length of all thread acting as a drawbar. My 4 jaw chuck can
be mounted right over the top of this stuff, and I was pleased to find that the gear locks up solidly when it's all in place.
Loosening the set screw is all it takes to move the gear to the next tooth. Now all I have to do is make the part!
Last edited:
- Joined
- Jul 14, 2017
- Messages
- 2,451
Today i had to do one job in a hurry but i still had this project chuck up in my lathe so i quickly finished it. started with a clean up pass then i started taking cutting passes on the smaller part, when i was at size i chamfer the edges and parted it off. This is a piece of a bigger puzzle for a in line drilling machine.
Continued on with my broom project (from https://www.hobby-machinist.com/thr...you-make-in-your-shop-today.67833/post-648061)
Got the belts, and I think I nailed both lengths. Got everything together, with the belts, cut off the corners interfering with the caster wheels, started it up, and the broom brooms in the correct direction. Yay. Then it kind of folded in half around the pivot point between the broom and the drive unit because the original broom lifting mechanism also has a stop to prevent this from happening. So, I've begun making a similar lifting mechanism, but didn't get it done.
Bercomac did something annoying as part of their broom, in that they used washers as a spacer between the gearbox and it's mount. Normally, it's NBD, but in this case, they are vertical, there's no way to hold them in place during assembly (they are at the back of a box holding the gearbox), so they don't readily stay in place. After trying and failing a couple of times, I finally decided to glue the washers in place with RTV. Makes a bit of a mess, but it's not visible at all, and it should hold them in place if I need to disassemble it again. And if I ever remove the gearbox entirely, I'll probably weld the washers in place.
Here of some pics of 2 of the 3 washers (you can just see them at the end of the bolt holes):
Got the belts, and I think I nailed both lengths. Got everything together, with the belts, cut off the corners interfering with the caster wheels, started it up, and the broom brooms in the correct direction. Yay. Then it kind of folded in half around the pivot point between the broom and the drive unit because the original broom lifting mechanism also has a stop to prevent this from happening. So, I've begun making a similar lifting mechanism, but didn't get it done.
Bercomac did something annoying as part of their broom, in that they used washers as a spacer between the gearbox and it's mount. Normally, it's NBD, but in this case, they are vertical, there's no way to hold them in place during assembly (they are at the back of a box holding the gearbox), so they don't readily stay in place. After trying and failing a couple of times, I finally decided to glue the washers in place with RTV. Makes a bit of a mess, but it's not visible at all, and it should hold them in place if I need to disassemble it again. And if I ever remove the gearbox entirely, I'll probably weld the washers in place.
Here of some pics of 2 of the 3 washers (you can just see them at the end of the bolt holes):
- Joined
- Jul 14, 2017
- Messages
- 2,451
Yesterday i got a call from a friend about a job he has taken on for fixing a gearbox from a rock quarry, he is a welder, so he welded the worn down bearing and seal journal. He asked couple other machine shops but they said they won't turn down welded shafts because it breaks their tools, others said they shaft is too big for their machines. Any how i started by getting on top of my lathe bed and using two straps to raise it in the chuck, the shaft must weigh 60 kg after i had it chuck up i indicated it and bump it around till i got it perfectly straight, then i got my steady rest in place to hold the good bearing end so i can center drill it , i used my big 16mm centre drill and made a fresh centre hole so i can hold it with a live centre, then i removed the steady rest and supported the end with a new russian made live centre, for a tool i used left carbide insert tool holder and did broke couple of inserts, you can see how the broken insert pushes the material in front of him and makes ring and many runners from it. Mid way thru the job i stopped and brought the tool holder as far back as i could to make it more rigid, the wire used to weld it was pretty hard, but the lathe hand no difficulties on the hard spots broke the insert didn't even slow down, i finish the work with cutting couple of radiuses by hand to make installing it easier, also the surface finish that i got straight from the lathe as you can see was really fine. Removing the shaft from the lathe was easier but still hard can't image some of the youtubers that show machining a 9 inch shaft how would they loud it or unload it without a crane. Hope you like seeing how shafts are repaired here.
