Rigidity is paramount in small hobby lathes. Check your gib adjustment on all slides. Also move the compound towards the center of the lathe. Try to use the maximum amount of dovetails in the compound and cross slide. Make sure the center of the tools are at the center of the work.
Thank you - yours the first video's I've found that actually show usage of the machine instead of just talking like other publishers. Rockin' the Fidel Castro look too!
As a rule of thumb, unsupported stickout shouldn’t be more than 2x stock diameter - so 1” round bar shouldn’t stick out more than 2” - otherwise you’re asking for a ride into chatter town, always work as closely to check chuck as you can for maximum rigidity - but like you, I learned by trying! Blondihacks lathe series is fantastic for learning!
Regarding parting, at 11:55 the part is running true. At 12:13 the part is wobbling. I believe the lateral pressure from parting caused the part to move in the chuck meaning the chuck wasn't tight enough. I am not an expert though.
Do you think this lathe can be operated while sitting (if the height was lower). I am not sure if I can manage leaning over for long periods of time. Thx.
I just set my shop stool up and did some dry runs to see how it felt. I had to extend my shop bar stool to its full height, but it felt fairly comfortable. It does slightly reduce your range of motion. But if you're making small parts I think it would work just fine. Sorry for the late reply.
Hi, nice lathe. Very quiet too! Regarding parting, some food for thought: - How thin is your blade? It flexed a lot when you started the cut, almost like if you were parting off on a threaded section (with a thin blade). I'm not seeing the holder moving, only the blade flexing, so maybe that blade was too thin (and the RPM was too low). - You didn't seem to have excess stickout for the cut, but maybe it was too much for the thickness of the blade. - Also it doesn't seem to me that you had the tool off center, it was cutting nice curly chips. - When starting, with HSS, slow will get the job done - but I think you're going too slow. 1018 with 20mm O.D. I think I'd start with 150-180 RPM with a 3/32nds blade. "Same" lathe. - Looks like the entire compound lifted when the blade broke. I'd check the compound play in all joints from the cross slide upwards. Also wouldn't hurt to check the carriage play. But at the least the compound should be locked during the operation and in a position where the parting tool is overhanging the cross-slide. Sorry for my poor english, I'm trying to help with little things that might make a difference. - There was some wobbling on the part before the blade broke, which wasn't happening at the beginning of the cut. Did the blade dig into the work and stalled the motor at some point (not shown on camera)? Sorry to ask but the times it happened to me, the part always ended up like yours (wobbling). And then yes, it runs crooked and the part grabs the blade. - Confidence and feel play a big role on the parting operation. Don't give up, you'll get there! (I had never seen a blade breaking before, yikes!) Stay safe!
Thanks for watching and your feedback. I agree that the RPMs were likely to slow. I'm a bit more confident now on the lathe in general, but still struggle a bit with parting. Luckily from what I can tell I haven't damaged anything or caused excessive play. Now, when I part, I also tighten up my gimbels. Which has been helpful. I just need some steady practice . Thanks again for the tips!
I'm not a pro by any means. But watching the video back a few times, it looks like there was a lot of runout on the part a couple of seconds before it broke. Maybe too much infeed creating tool pressure to be high. I ordered this same machine, I'm just waiting on delivery. I can't wait to make some chips.
Regarding your tailstock, when it's set up correctly, you use the lever at the rear to lock it in place. No need to use a wrench on the nut. That's what the lever is for.
Check out the edge technologies height setting tool. Its absolutely a game changer and is faster and more accurate than eyeballing the tool height. They arnt really that expensive either.
I got the PRO LATHE GAGE 02-000. I used to scoff at these sort of tools for a hobbyist but theres no way I could measure it by eye as accurately as that can.@@steelforestweldingandforge
Regarding the parting tool snapping... watch your video right at the start of the cut, at about 12:10. The parting blade is moving up and down A LOT. You see that, you back off immediately, something wasn't tight or squared up. There is a jump cut at 12:12, and unfortunately, I think you edited out where things went really wrong, as after the cut the part is wobbling at the tailstock end. Maybe it shifted in the chuck, maybe something else is loose... hard to tell with the key part of the video missing. It doesn't take much to snap a part-off blade. Every machinist has done this, many times. it can happen even if the setup is as perfect as you can get it, just from a chip pushing the blade a little bit too deep into the workpiece; if the side of the blade digs in, it's game over.
Your RPM is too low as you’ve been told already, but the depth of cut is too shallow as well. Your depth of cut should be around half of the radius of the tool for turning. So if you’re using an insert that has a.03 radius your depth should be .015. As for the parting tool, it was probably chip build up due to the low RPM and an inconsistent feed rate. Don’t get discouraged. Get a copy of Machinery’s Handbook and practice with something more forgiving like nylon. When we were taught how to use a lathe in school we all started with nylon before moving on to brass, then aluminum and finally steel.
More RPM. Cs×4÷Dia is what works for me. So if you have 5/8" steel, which is 100 for the Cs, you'd do 100×4÷.625=640 RPM. It appears you were going too slow at the start.
There is always some runout with 3 jaw chucks. After facing and turning it shouldn't wobble. I believe you can get it to run true with 4 jaw chucks but it takes effort and I've never done it.
Your speeds are way to low. Turn your compound 180deg. Always try to cut on a forward direction. Maybe your parting tool was lower than the centre point. When you cut the face and drilling a centre drill, work piece as close to the chuck as possible.
How is your PM lathe working out. I am a retired machinist and always planned on purchasing a lathe before retirement. Very disappointed in all the youtube videos I have watched because the money you all spend for what you are getting. Yes I am spoiled. I had access to every machine imaginable in the shop I worked in. The only lathe I have seen that comes close to quality is Baileigh. Alot more $$$. I would like at least a 12x36.
Rigidity is paramount in small hobby lathes. Check your gib adjustment on all slides. Also move the compound towards the center of the lathe. Try to use the maximum amount of dovetails in the compound and cross slide. Make sure the center of the tools are at the center of the work.
Thank you - yours the first video's I've found that actually show usage of the machine instead of just talking like other publishers. Rockin' the Fidel Castro look too!
As a rule of thumb, unsupported stickout shouldn’t be more than 2x stock diameter - so 1” round bar shouldn’t stick out more than 2” - otherwise you’re asking for a ride into chatter town, always work as closely to check chuck as you can for maximum rigidity - but like you, I learned by trying! Blondihacks lathe series is fantastic for learning!
I'm a big fan of blondihacks! Thanks the advice.
Regarding parting, at 11:55 the part is running true. At 12:13 the part is wobbling. I believe the lateral pressure from parting caused the part to move in the chuck meaning the chuck wasn't tight enough. I am not an expert though.
Do you think this lathe can be operated while sitting (if the height was lower). I am not sure if I can manage leaning over for long periods of time. Thx.
I just set my shop stool up and did some dry runs to see how it felt. I had to extend my shop bar stool to its full height, but it felt fairly comfortable. It does slightly reduce your range of motion. But if you're making small parts I think it would work just fine. Sorry for the late reply.
Hi, nice lathe. Very quiet too!
Regarding parting, some food for thought:
- How thin is your blade? It flexed a lot when you started the cut, almost like if you were parting off on a threaded section (with a thin blade). I'm not seeing the holder moving, only the blade flexing, so maybe that blade was too thin (and the RPM was too low).
- You didn't seem to have excess stickout for the cut, but maybe it was too much for the thickness of the blade.
- Also it doesn't seem to me that you had the tool off center, it was cutting nice curly chips.
- When starting, with HSS, slow will get the job done - but I think you're going too slow. 1018 with 20mm O.D. I think I'd start with 150-180 RPM with a 3/32nds blade. "Same" lathe.
- Looks like the entire compound lifted when the blade broke. I'd check the compound play in all joints from the cross slide upwards. Also wouldn't hurt to check the carriage play. But at the least the compound should be locked during the operation and in a position where the parting tool is overhanging the cross-slide. Sorry for my poor english, I'm trying to help with little things that might make a difference.
- There was some wobbling on the part before the blade broke, which wasn't happening at the beginning of the cut. Did the blade dig into the work and stalled the motor at some point (not shown on camera)? Sorry to ask but the times it happened to me, the part always ended up like yours (wobbling). And then yes, it runs crooked and the part grabs the blade.
- Confidence and feel play a big role on the parting operation. Don't give up, you'll get there!
(I had never seen a blade breaking before, yikes!) Stay safe!
Thanks for watching and your feedback. I agree that the RPMs were likely to slow. I'm a bit more confident now on the lathe in general, but still struggle a bit with parting. Luckily from what I can tell I haven't damaged anything or caused excessive play. Now, when I part, I also tighten up my gimbels. Which has been helpful. I just need some steady practice . Thanks again for the tips!
I'm not a pro by any means. But watching the video back a few times, it looks like there was a lot of runout on the part a couple of seconds before it broke. Maybe too much infeed creating tool pressure to be high. I ordered this same machine, I'm just waiting on delivery. I can't wait to make some chips.
So, part sticking out too far and feeding to aggressively? Noted. Thanks for the feedback!
Regarding your tailstock, when it's set up correctly, you use the lever at the rear to lock it in place. No need to use a wrench on the nut. That's what the lever is for.
@@GeneralDesignInnovation-es4zz noted, thank you
Check out the edge technologies height setting tool. Its absolutely a game changer and is faster and more accurate than eyeballing the tool height. They arnt really that expensive either.
I will DEFINITELY be looking into that. Thanks!
I got the PRO LATHE GAGE 02-000. I used to scoff at these sort of tools for a hobbyist but theres no way I could measure it by eye as accurately as that can.@@steelforestweldingandforge
Regarding the parting tool snapping... watch your video right at the start of the cut, at about 12:10. The parting blade is moving up and down A LOT. You see that, you back off immediately, something wasn't tight or squared up. There is a jump cut at 12:12, and unfortunately, I think you edited out where things went really wrong, as after the cut the part is wobbling at the tailstock end. Maybe it shifted in the chuck, maybe something else is loose... hard to tell with the key part of the video missing. It doesn't take much to snap a part-off blade. Every machinist has done this, many times. it can happen even if the setup is as perfect as you can get it, just from a chip pushing the blade a little bit too deep into the workpiece; if the side of the blade digs in, it's game over.
@@shiphorns Thanks for the advice. I'll take a closer look at where you recommended.
Your RPM is too low as you’ve been told already, but the depth of cut is too shallow as well. Your depth of cut should be around half of the radius of the tool for turning. So if you’re using an insert that has a.03 radius your depth should be .015.
As for the parting tool, it was probably chip build up due to the low RPM and an inconsistent feed rate.
Don’t get discouraged. Get a copy of Machinery’s Handbook and practice with something more forgiving like nylon. When we were taught how to use a lathe in school we all started with nylon before moving on to brass, then aluminum and finally steel.
Very solid advice. Thanks for the input.I'll take a look at that book.
More RPM. Cs×4÷Dia is what works for me. So if you have 5/8" steel, which is 100 for the Cs, you'd do 100×4÷.625=640 RPM. It appears you were going too slow at the start.
Thank you for the advice and formula.
Please forgive my ignorance, what does the "C" represent in your formula?
@dennis900 Cs- Cutting speed. In the millwright manual, there's a chart of cutting speeds for different materials. Mild steel is 100.
Why is it always the part being worked on is wobbly? I usually use square to make sure it's straight, but it's always wobbly!
Sorry but could you be a little bit more specific? I'll try and help but again.I'm not a machinist by trade.
There is always some runout with 3 jaw chucks. After facing and turning it shouldn't wobble. I believe you can get it to run true with 4 jaw chucks but it takes effort and I've never done it.
Your speeds are way to low. Turn your compound 180deg. Always try to cut on a forward direction. Maybe your parting tool was lower than the centre point. When you cut the face and drilling a centre drill, work piece as close to the chuck as possible.
What speeds would you recommend? I did center the cutting tool on the tailstock dead center. Thanks for the info.
What model is your lathe??
pm-1030v
How is your PM lathe working out. I am a retired machinist and always planned on purchasing a lathe before retirement. Very disappointed in all the youtube videos I have watched because the money you all spend for what you are getting. Yes I am spoiled. I had access to every machine imaginable in the shop I worked in. The only lathe I have seen that comes close to quality is Baileigh. Alot more $$$. I would like at least a 12x36.
Thats a lot of stick out without a center.
noted
My advice would be to get some actual live help and learn the difference between a RH and LH tool. Making videos may not be the best way to start off.
I've found its alot safer and cheaper to eat chips on the couch than it is to make chips in the shop ....... 🩸 🤕
You're not wrong