One of the best for details. Just one request, do you cover reading the layout or image in one of your other videos? My boss/instructor is from East Germany, and I'm not sure I'm understanding the process right for using the layout medium.
No sorry, there is no detailed (or any) description how to read the blue. I thought about making a video about that for several times. But it would require some animation tools I don't have. I tried to collect shots of clear readings, but that also failed.
Maybe once I'll come up with a description. As soon as you understand what the blue does, it's easy to draw your own conclusions. I never found a clear explanation. Maybe, I'll try it with some sketches.
hello; had to laugh on your comments. bulls eye! IMHO. i have a chinese built lathe labelled for marketing by a tool company in 1 of 2 north american countries(do not know the legalities of commenting here but rather not be sued). this video gives me hope i can rectify my carriage, crossslide, issues . my tailstock and carrige have been scraped to the ways with a mini grinder. please continue with the videos. your knowledge can save us from the fate of this junk from china.
If I may ask...where I can find detailed information about scraping.It may sound stupid...but why not to machine on grinding machine?Wich is the difference between a scrapped surface and a polished surface? The scraped surfaces are they mating together during operation or there is an oil film between them?Can this be done on larger machines (lathes wich can machine pieces 1-2 m length )?
I would be willing to bet a lot of the distortion in Chinese machine ways is do to not stress relieving the casting before machining. Hopefully it has moved as much as it's going to before you do all that work to it.
I dont understant the part where u measure the dist. from the side of the carraige to the dove tail, what good is that reference? Do u use the home made prism to mark the dovetail or for someting else, can the traverse slide be used?
@Axbent If you look at the guide for the crossslide, it has to be perpendicular to the guide for the bed. Now I don't have the bed, so I need some other reference that is more or less parallel to the crossslide. That reference was the granite angle. Now I measure the distance from angle to dovetail at the front and set the dial to zero. Second measure from angle to rear of the dovetail. That gives some value (in this case it was IIRC 0.17 mm). I know that the cross slide has to be rotated ...
@MuellerNick Understood, but dont you just end up with a dovetail that is non converging if the faults are corrected. Not having the lathe bed must be rather critical? The centerline on the CS dovetail could be off from 90° to the bed?!
Also what did you mount the scraper in for the motorization of it?
The cross slide had been measure by the client at site and I was told that it is off my a certain amount. So I only had to a) get some repeatable reference and then b) had to rotate the guide by the tad that I was told. Client was happy with the result. I don't want to promote this as the best way, but it was the best doable way (except shipping the bed; $).
I worked with two tools: A manual scraper and an electric one, called BIAX. I think the BIAX can be seen in the Myford #3 video
@Axbent ... by amount X (0.035mm) So I scrape the dovetail and shift the tilted plane by guessing and measuring by the desired amount. That amount is reached when I measure again and the difference between front and rear is 0.25mm (see notes on the part).
The prism is needed for marking the tilted sides of the lower part. After that, the lower part's tilted sides are the master for the upper part. Look at my video "Scraping in a lathe's top slide", it describes the sequence in detail.
thanks for making this video- its been very helpful- great job!
The87wing 2 weeks ago
at 8:43 the chief engineer gave approval lol
FueShuN 3 months ago
One of the best for details. Just one request, do you cover reading the layout or image in one of your other videos? My boss/instructor is from East Germany, and I'm not sure I'm understanding the process right for using the layout medium.
Tombfyre80 4 months ago
@Tombfyre80
No sorry, there is no detailed (or any) description how to read the blue. I thought about making a video about that for several times. But it would require some animation tools I don't have. I tried to collect shots of clear readings, but that also failed.
Maybe once I'll come up with a description. As soon as you understand what the blue does, it's easy to draw your own conclusions. I never found a clear explanation. Maybe, I'll try it with some sketches.
MuellerNick 4 months ago
hello; had to laugh on your comments. bulls eye! IMHO. i have a chinese built lathe labelled for marketing by a tool company in 1 of 2 north american countries(do not know the legalities of commenting here but rather not be sued). this video gives me hope i can rectify my carriage, crossslide, issues . my tailstock and carrige have been scraped to the ways with a mini grinder. please continue with the videos. your knowledge can save us from the fate of this junk from china.
billgator2005 9 months ago
Hello.
If I may ask...where I can find detailed information about scraping.It may sound stupid...but why not to machine on grinding machine?Wich is the difference between a scrapped surface and a polished surface? The scraped surfaces are they mating together during operation or there is an oil film between them?Can this be done on larger machines (lathes wich can machine pieces 1-2 m length )?
Thank You.
P.S.: I don't know nothing about scrapping.
princeigorash 1 year ago
@princeigorash
Forums like HomeShopMachinist of PracticalMachinist talk about scraping. You'll find information there.
Two polished surfaces adhere to each other, they don't glide very well. Oil pockets at one side are essential for good tribology.
MuellerNick 1 year ago
I would be willing to bet a lot of the distortion in Chinese machine ways is do to not stress relieving the casting before machining. Hopefully it has moved as much as it's going to before you do all that work to it.
ardvarkkkkk 1 year ago
Comment removed
phibieb 1 year ago
I am interested to learn basic scraping. what model manual scrapper is that? where can they be purchased.
phibieb 1 year ago
@phibieb What country are you from? I mean, if I tell you that I bought it at Hoffman Munich, is that of any help?
Any Sandvik dealer should have them. But there are other manufacturers.
MuellerNick 1 year ago
Nick: Thanks for the lesson. Who is the lathe Manufacturer?
I guess this is typical quality?
petsatcom 1 year ago
@petsatcom I don't know the manufacturer, and am not sure about the importer. But yes, that's about the average "quality" you get.
MuellerNick 1 year ago
@MuellerNick There is an art to scraping, i lost it 30 years ago.
Removing metal by guessing, then whats to say its not parralel, warped 3 dimensionally etc These chinky castings move when machined.
Seen loads of beds scraped in 'i only took a couple of thou off' to put right needed 30+ thou on all faces to put right.
If you would have smoked it or blued it and trial and error removing in right areas, then yes.
Assume the underside was trued up first, if not fighting a lost cause.
jhareng 1 year ago
Thank you Nick you patience and precision is inspirational.
Alan
jackary2003 1 year ago
Great vid,
ahz123 1 year ago
I dont understant the part where u measure the dist. from the side of the carraige to the dove tail, what good is that reference? Do u use the home made prism to mark the dovetail or for someting else, can the traverse slide be used?
Axbent 1 year ago
@Axbent If you look at the guide for the crossslide, it has to be perpendicular to the guide for the bed. Now I don't have the bed, so I need some other reference that is more or less parallel to the crossslide. That reference was the granite angle. Now I measure the distance from angle to dovetail at the front and set the dial to zero. Second measure from angle to rear of the dovetail. That gives some value (in this case it was IIRC 0.17 mm). I know that the cross slide has to be rotated ...
MuellerNick 1 year ago
@MuellerNick Understood, but dont you just end up with a dovetail that is non converging if the faults are corrected. Not having the lathe bed must be rather critical? The centerline on the CS dovetail could be off from 90° to the bed?!
Also what did you mount the scraper in for the motorization of it?
Axbent 1 year ago
@Axbent
The cross slide had been measure by the client at site and I was told that it is off my a certain amount. So I only had to a) get some repeatable reference and then b) had to rotate the guide by the tad that I was told. Client was happy with the result. I don't want to promote this as the best way, but it was the best doable way (except shipping the bed; $).
I worked with two tools: A manual scraper and an electric one, called BIAX. I think the BIAX can be seen in the Myford #3 video
MuellerNick 1 year ago
@Axbent ... by amount X (0.035mm) So I scrape the dovetail and shift the tilted plane by guessing and measuring by the desired amount. That amount is reached when I measure again and the difference between front and rear is 0.25mm (see notes on the part).
The prism is needed for marking the tilted sides of the lower part. After that, the lower part's tilted sides are the master for the upper part. Look at my video "Scraping in a lathe's top slide", it describes the sequence in detail.
HTH!
MuellerNick 1 year ago
Big thanks for this superb vid!
Axbent 1 year ago
Thank you SO MUCH!! I really want to learn to scrape! I'm going to check out more of your videos!!
BabyHominid 1 year ago
Thank you very much Nick. You are the one who introduced me to scraping.
hla27b 1 year ago
@hla27b
One of the nicest compliments I could get! But don't curse at me if it takes longer than expected. ;-)
MuellerNick 1 year ago
Thank you Nick you patience and precision is inspirational.
Alan
jackary2003 1 year ago