Mapping the South bend Lathe slideways (Part 3)

[@ypaulbrown]

Thank You Paul, Paul from the USA......

[@paulhewitt1488]

Absolutely enjoyable watching a true craftsman go about his work. The dedication and data collection you are using to bring this old lathe back to life is fantastic. Thank you so much 👍👍

[@Thesheddweller]

Hi, thanks, I use it quite a lot now. Cheers.

[@lecnac855]

Very astute reasoning and application. Common sense supercedes genius by its simplicity. Well done as usual.⭐

[@Thesheddweller]

Hi, thank you. regards

[@raikbusse7697]

I find it very remarkable how much effort you put into finding out the geometry of the "old" machine to know how accurate it is. Too bad that few "viewers" are of the same opinion. I have learned something. So thumbs up. Greetings from Germany, Raik

[@Thesheddweller]

Hi, thank you for your comments, I am still learning and I intend to for a few more years. regards

[@colincreedtattoomachines]

Looking forward to seeing your "contraption" as I'm sure it'll be creative & ingenious as the rest of your series has been so far.

[@Thesheddweller]

Hi, Oh you can bet your bottom dollar that I’ll find something to do the job. regards.

[@stevengehm1287]

As an old guy myself, I enjoy watching other old guys using what they have available to get and understanding of what they are dealing with. Takes alot of time, but sure beats watching Soap opera's with the wife.....

[@Thesheddweller]

Hi, I agree (with everything), cheers

[@miketherefurbisher8000]

Hi Paul. Extremely interesting. Thanks

[@Thesheddweller]

hI, thanks, cheers

[@wowcoolm860]

Absolutely hooked! You're clearly a skilled bloke. You are giving me some confidence to tackle my old Erikson Emato 180-NE. Keep up the great work and keep British engineering alive!

[@Thesheddweller]

Hi, thank you, I’ll certainly try. cheers

[@leslieaustin151]

Such effort! Such understanding of what you’re about! This is magic to me, but so interesting. Thank you. Les

[@Thesheddweller]

Hi, thank you. Elbow grease also helps make the magic work so much more rewarding. regards.

[@mrcpu9999]

You had me at "contraption". Haven't seen a good contraption in ages, so the bar's gonna be pretty high for yours....

[@Thesheddweller]

I have't had a good contractionfor ages...😆

[@TheKnacklersWorkshop]

Hello Paul, Look like it is going to work out very well... well done... Take care. Paul,,

[@Thesheddweller]

yeah. It’s a bit of a headache at the moment. I’m thinking of using a technique that if it doesn’t work,…means I’ll have to sell it off for spares. I’m also quite busy with other stuff for old cars and bikes, they still need repaired parts.

[@humanistwriting5477]

Absolutely beautiful work, I'm keen on a bet that you will do better then some "professionals" for certain.

[@Thesheddweller]

Hi, thank you.

[@andrewdolinskiatcarpathian]

Very interesting. Thank you 👏👏👍😀

[@Thesheddweller]

Hi, cheers.

[@Kevin-gx8lc]

Hi Paul, I'm following this series of your videos with keen interest as I will soon be commencing work on my newly acquired Myford Super 7 (my first ever lathe, a 1961 model) which I hope will not be quite as complicated as your current project… the Myford S7 has flat ways so fewer faces than your challenging American piece of cast iron! Keep up the great work. Greetings from Southport.

[@Thesheddweller]

Hi Kevin, I'm glad to be of help. regards.

[@garygenerous8982]

Honestly im surprised there wasn’t more wear on the machine outside of those carriage v ways. Looking forward to seeing how you decide to tackle it.

[@Thesheddweller]

Hi, so am I. There is wear all over, but it's so small that only a professional outfit can put that right. I am attempting to reduce the large error on the main slides, I don’t think I can remove it. cheers

[@HaxbyShed]

Paul, I copied your method to measure for twist on the bed of my Harrison 140 today. It confirmed the bed is true and not twisted but a separate test showed wear, so I'll be very interested to see if/how you regrind the v-ways. Regards.

[@Thesheddweller]

Hi. Me too.. I haven’t started looking at that yet, I’ve been too busy with other stuff. Regards

[@greglaroche1753]

Very interesting. Thanks.

[@Thesheddweller]

Hi, thanks.

[@alasdairhamilton1574]

Hi, will you be hand scraping or using a biax scraper? Wishing you success which ever you use🥵😰🤗. 👍🏴󠁧󠁢󠁳󠁣󠁴󠁿

[@Thesheddweller]

Hi. A biax scraper is something I don’t have and I could never afford one of these machines. They cost more than 4 times what I paid for the lathe. I’ll probably just stick to using a hand scraper and Heath Robinsons hand book. cheers.

[@AJBtheSuede]

Good work :) Best of luck, for sure it will be a big improvement.

[@Thesheddweller]

Hi, thank you, i’ll give it my best. cheers.

[@gregwmanning]

Your task is so interesting, I am keen to follow it through. How do you think the front face "high" spot came about?

[@Thesheddweller]

Hi, I’ve gazed at this conundrum for a while now… My conclusion…. still haven’t a clue. regards.

[@samuelfielder]

Great stuff! You keep saying things like "point oh one three dip - that's about five thou". Actually 0.013 mm is 0.5 thou. So I'm thinking I should mentally delete the "oh" in every case.

[@Thesheddweller]

Hi, you’re the first one to hear that error. It was in fact 5thou lower… I got the point and ‘oh’ the wrong way round. It should have been 0.13mm I’ll have to see about putting a oops there as soon as I can, mind you with the amount of views it has had it’s almost not even bothering with. Cheers for that Regards

[@andyknappenberger7512]

I'm gonna check my South bend at work. I could probably use a Sawzall'd chunk of wet pine to confirm it's clapped out.

[@Thesheddweller]

Hi, sorry i didn't reply, I missed your comment. I guess ifn its more than 30years old a bit of dry pine would work🤣. Cheers

[@craigtate5930]

some time back I checked my hendey with very rudimentary techniques...nothing more then a homemade V block and digital calipers...if I recall correctly I saw around .030 wear near the chuck...so I am definitely interested to see how you get on with your project so I can gain from your experience

[@Thesheddweller]

Hi, I recon any improvement is an improvement that will make a difference to any machine. I now know the gear is as sweet as a nut under power. Regards.

[@mikeparfitt8897]

The more rigidly the two 1 inch parallels are coupled and the larger the "contact" face area, the more they average out the tiny differences between the surfaces they each run along. This may be what you want when you are indicating a third surface, but works against you when trying to compare the relative orientation of the two surfaces the parallels are running along.

[@Thesheddweller]

Hi, quite right… thats why I used a less rigid threaded rod to allow flex to prove that there is little parallel error between the two slides while running along the length of them. regards

[@carlwilson1772]

I can only gawp in awe. To be honest, I feel a bit like a chimp having the workings of a swiss watch explained to him. I do not fully understand how lack of parallelism in the flat ways would show up on the dti, using the method shown. If the ways were not parallel, but still coplanar then surely no dti movement would result. If parallel but not coplanar, then the dti would move. So they could be coplanar but not parallel. Which is maybe all that matters. In truth I haven't a Scooby.

[@Thesheddweller]

Hi, the two linked parallels simply compared the parallel relation of the two slides, because I am ultimately looking for a way to repair the two saddle vee supports and knowing as much as possible means measuring much as possible. Just imagine linking the two parallels together like I did, but on a flat surface. Then put a mag mount on one parallel, with a DTI reaching over to the other parallel. The reach between parallels in my case was about 200mm (about 8”). If the parallel with the mag mount was tipped over by say one thou, like would happen if the two slides weren’t parallel, then the DTI will show a several thou error. Therefore, if the DTI shows no movement, then the sides of the parallels aren’t being squashed together or forced apart, tipping them over. in this case indicating that the slides are in fact parallel. hope this helped, cheers

[@carlwilson1772]

@@Thesheddweller I think it is something I would have to do and see myself. I cannot see how the two flat slides not being parrallel, ie not diverging apart or converging together could result in any movement of the dti. If they diverge or converge, but are still in the same plane, then there can be no relative movement of the two blocks giving an indication on the dti. If they were not coplanar, ie if one sloped down or up relative to the other, then there would be. I totally get that the more measurements you take, the more you know and therefore the better job you can make of it. I am convinced I am still missing something here. Never mind though. I will keep watching and eventually the penny will drop.

[@inceptori]

instant sub

[@NellsMechanicalManCave]

Mmm! An angle grinder isn't going to work in this situation is it? I know scraping is the normal course of action to correct this, but,,,, going back to making your straight edge and surface plate. Could a long sacrificial form tool and say grinding paste be used to take out the bulk? This isn't something I'm familiar with and know nothing about, but you use a long block to rub out a dent in a flat surface to correct it

[@Thesheddweller]

Ah… the trouble is, there’s an enormous amount of metal to remove, you are right about the scraping side of things and I’m going to have to swot up on studies made by my hero Heath Robinson…… regards

[@NellsMechanicalManCave]

@@Thesheddweller Plan B then ! A carriage that runs on your true faces with that angle grinder on it 🤣🤣🤣

[@jonedmonds1681]

2 thou over that length is a massive amount of metal to remove with a scraper, hitting the highs with an angle grinder, until you’re within 1/2 a thou then finish with scraping has often been done by others. How about, clamp the angle grinder to your top slide, mount / clamp topslide on top of those parallels, grind 4” advance 4” clamp down, rinse and repeat.

[@nrml76]

A pneumatic die grinder mounted on the ''parallel sledge'' taking very light passes would get you within reasonable range with good control. The problem with angle grinders or other high power devices is that the lack of mass and rigidity in the whole set up to cope with vibration. An arrangement for fine feed and the ablility to swing through 180 degrees would allow it to tackle the angled faces as well as the outside and top faces. I look forward to seeing your solution.

[@Thesheddweller]

@@NellsMechanicalManCave Now there’s an idea,…...

[@paulpahl1607]

The only measurement that makes sense for me is @8.30...

[@Thesheddweller]

Hi, the previous measurements were taken for comparative reasons. Then placed on a computer spread sheet where all the figures could be compared with each other for analysis. This form of analysis was easier than using the data I wrote on pits of paper.

[@АлександрБренгауз]

ok

[@Thesheddweller]

👍