The Marvel Saw is by far one tool that a man would be proud to own let alone use, Thanks Tom for showing.

Did I really just spend 25 minutes watching a man rub 2 pieces of metal together? Seriously, incredible work. Thanks!

The optical flat is fascinating! Never heard of that before. Thank you for sharing this with us.

Hey Tom, great video! Get yourself a box of the 4.4 x 8.4 Kimwipes. Put a single layer of the Kimwipe on the part and then put the optical flat on top. Now slowly drag the Kimwipe out from between them and you will have a perfectly clean interface where you will be able to manipulate the flat to get the band spacing and direction you desire. Also fold a piece of paper into an inverted hat shape and put it in the vise and then grab the lap with the paper lined vise so all that lapping debris does not lube your vise but stays on the paper. ATB, Robin

The way people figured out how to measure things is astounding to me. I mean, I understand that the measurements my digital calipers spit out come from a measurement on a wave but to then see that broken down into it's base components and then expanded on in another direction like this is a real treat.

Wow. That gives me new respect for the gauge blocks. I mean I know they're good, but those lines are straight!

I wish I could find one of those old Marvel band saws for a reasonable price. I worked in three shops that had them and the were indeed a marvel. At one shop, the automatic feed had gone out years before and I was told that they couldn't get parts for it. I took it apart during my breaks and found out that all that was wrong was the pin on the worm gear was sheared and the clutch was worn out. Since the clutch was actually made from cork sheeting, I took a cork bulletin board and peeled the cork off it and that became the new clutch. It was still working just fine a year later when I left that job for another.

Very cool to see that. Thanks for sharing Tom.

In my carer as a mech. in a power plant, I lapped safety valves on every overhaul.On the finish lapping ,would use 1000 grit,and just keep lapping and wiping the valve seat until the compound would break down so fine that the seat would would become a mirror finish,,,the seat would become so smooth it would become a filament finish,or you could see a flashlite filament in the seat...

Brings back memories of running lapping machines when I worked as a hydrostat mechanic. We had a six inch diameter optical flat that I kept locked in a drawer so that the hammer and chisel mechanics couldn’t bust it. We had several lappers and the largest was about 60” in diameter. I would batch test and adjust the rings in or out to compensate for wear on the lapping surfaces which in turn adjusted the flatness of the plates being lapped. In that set-up, flatness was a constantly moving target.

Used a saw just like that working maintenance in a steel mill good memories thanks for the video 👍

The McD’s lunch tray is the real gem of precision in today’s video! This is an absolute killer for knocking out ignorance! Warm water changing shapes because yes, we are capable of working on THAT level in our shops. Damn dude, you are awesome. Thank you.

Very interesting video. Back when I was a SeaBee in Vietnam, we actually had a lapping plate to rebuild fuel injectors or maybe the pumps on diesel engines. We didn't have an optical flat to test it however. I don't think we were looking at that level of precision. It seems to me the lapping plate was 6 to 8 inches square.

Extremely interesting subject. Thanks for the education and take care Tom!

That is one marvelous bandsaw you have in your shop.

I don't find videos like this boring at all. There is something very hypnotic about it. Almost like an asmr video, but without the weird noises

Not boring at all. Nice saw, thanks for showing us.

Super cool, like the optical flat shows some cool info about the surface finish

Fascinating. I was part of a tour group in the early '60s where the company made hydraulic motors in Southern California. The swash plates (I recall that being the name) were lapped and measured on a machine like that. As I recall they were used for aircraft flight controls

Very Interesting Tom, the monochromatic light is amazing, The Marvel saw is pretty cool too!

So that is what optical flats are fore. Really cool. Thanks for sharing.

Tom My first knowledge of optical flats come 50 years ago when as a Sparks was put on shift with a 60 year old Sparks mate , though time spent chatting between plant breakdowns it transpired he made gauge blocks (jo blocks ) during ww11 he when into great detail how they made them and the hand lapping process using CI Lapps and optical flats to test the results , and it's a bit footy now but a optical comparitor to get them on size , one thing that did stand out was the ruff ground the blocks then during them in the ground for two years ( greased up ) before finishing, he still had a couple of rejects that still wrung together , during the same time frame in ww11 dad worked on 18 foot HBM to bore and rifle large gun barrels ( he sett them up and the operators were all female )

Very cool seeing the optical flat and the interference rings! Great video.

"Zen and the Art of V-Block Maintenance" By Tom Lipton. On book stands this summer!

Interesting video, I wondered how true flatness was determined, now I have a glimpse of how, & what to look for. Thanks Tom!

Hip Hip Moiré on those patterns. Your lapping series solved my much lower resolution problem. I'll be lapping the bottoms of a new set of cast iron skillets [very nicely cast, but with a fine sandpaper-like as-cast surface from the casting sand]. I want the bottoms both smooth and flat so as to be non-abrasive and to get greater surface contact with the glass on an induction cooktop. Thanks Tom

That was cool! Thanks for the vid. You know us geeks are lapping it up...

Your a great teacher and mentor, thanks for the your time in show us your great knowledge around your workshop.

As a non-machinist (went to school for welding finished school and changed my mind) I am blown away at that finish. I didn't even know steel could be that mirror like. Nice work! Also making that "Lap" (?) was very interesting I have never seen that done and those cross hatches are really awesome looking. Any chance you could do a video on making one of those from start to finish?

probly the first time I've seen optical flats on youtube not a bad video at all I half expected a explination on how photons are particals the follow eachother around in waves and esentialy yer using a lazer to determin flatness its good to know how mr wizard love that saw that was what the press forming was bout ha awesome aqisition

VERY interesting....enjoyed!

Super interesting bit about the optical flat and monochromatic light source!! More, please! I would like to see how flat you can get your V block.

the last minute showing and explaining the lines was the best

Used a saw just like that one in the first fab shop I worked in. Cut MANY a stair stinger with it!

Multiple lessons in one video - very nicely done, Tom. It would be interesting to see other ways to check flatness for the small shop, but I think you've covered that in previous videos if I recall correctly. Hard to keep track after all of this time. Search button to the rescue! Thanks for sharing, sir. Tom Z

Tom's on a roll with introducing us to crazy ass new stuff most folks have never heard of before (me included!), the polariscope, the optical flat and a monochromatic light source by lapmaster. Being that I know a thing or two about lasers the "monochromatic" light source particularly piqued my interest, as most light sources emit a variety of wavelengths which we perceive as "white" (or yellow), I had thought that lasers were the only "lights" that we produce that operate on a single wavelength but that seems to not be the case, entirely anyways. Fascinating.

You ought to do a video in more detail on the feed mechanism on your Marvel saw. The way that works has to be one of the cleverest engineering designs I have ever seen.

Wow, you're truly the Norm Abram of the machine shop.

very interesting demo on how to measure flatness with light. camera work was very good.

It has been many years since my time as a job shop machinist , Though I remember a crystal similer to what you used and I believe it was a type of Calcite Optical Feldspar ... One of the Gem quality version of the Sun stone used by Nordic Vikings to site the sun for navigation... Could be wrong or close. I think I have forgotten way more than I have learned in my lifetime... Many Blessings , SMR

I would kill for a video showing how ol' Johansson did it with a Singer sewing machine.

Excellent information, Tom. Especially the part at the end evaluating with the optical flat. It's interesting because the laps you made look just like the laps used to polish mirrors for reflector telescopes. I believe the grinding material is also Aluminium Oxide; need to look see whether the Mirrors are ever finished with a diamond compound. I suspect the assessment of how well the mirror is made would be how concentric the bands are in the optical test setup the mirror fabricator uses. Thanks!

Hey Tom... first time I've seen the optical testing... very impressive... thanks to you I learned something today. Thank you for sharing your vast knowledge and being so casual about it... very much appreciated!

The things I learn from you, I swear I can not learn anywhere else.

In a future lapping video you should see if you can lap two parts flat enough to get them to wring together.

Excellent video, as usual, thanks Tom for sharing. I'm pretty sure you would enjoy telescope mirror grinding and lapping. Much of the same, but with the added fun of figuring a concave or convex shape (paraboloid, ellispoid, etc.) down to a few nanometres (when we're lucky). Hours of fun! For the final lapping, we commonly use pitch laps and cerium oxide.

very cool Ox. Thanks for the lesson

Hi Just found your channel, Awesome stuff, I used to lap carbon seal plates among other things back 25 yreas ago while building up Pratt & Whitney JT3 gas turbines for Boeing 707's we have come along way since then but I feel sorry for the kids these days they cant even read a mic or a Verynear haha let alone use a light source. I tell people and they are amazed what we used to do I worked over in Holland at the Frank Whittle engine shop for a few months and got the nick name MacGyver from my supervisor as they had all the kit but I was working out the moments of the fan blades for balance without a computer lol not rocket science back when i started we had to work everything out on paper lol cheers Phil.

Not boring! Very interesting.

You need some KimWipes. They are ubiquitous in labs, and with people who use microscopes. They are made from special paper they leaves no lint, and absorb an impressive amount of moisture considering they are closer to feeling like printer paper than tissue. I use them by the case in the lab, they are fairly cheap.

Oh it was very interesting thanks Tom

now that was very cool Tom.

it is really amazing as to the tools that are out there and to how fine measurements can be taken down to good Tom keep em coming

That measurement process really is something

Abraham Lincoln: Give me six hours to chop down a tree and I will spend the first four sharpening the axe. Tom Lipton: Hold my beer.

That optical flat, I saw one a couple of weeks ago for the first time in a "how its made" video about the starret micrometer production. Ofcourse in "how its made" tradition lacking all seriously interesting stuff. Thanks for the explanation I now understand the idea and it is pretty cool! It might also be horrible to have when you are a perfectionist.

That's a very cool saw. Thank you for the video

Fascinating to watch that Gauge block is amazing! Thank you. Learning new stuff is fun :)

Beautiful job

I can't press the "like" more than 1 times? This video is awesome! THX!

Excellent video Tom, specially the optical inspection part.

Always nice to see some of the stuff we were supposed to learn at school, for real! Thanks for sharing! ;)

Love that saw , never seen such a beast .

You've got my curiosity peaked for what the supper precise v-block is going to be use for. ??!!

Great demonstration Thanks for sharing

Saw envy. Nicely done.

Thanks Tom. Did the gauge block wring to the base? Did you finish up buying an autocollimator? You mentioned that at one stage. If so, set the V on a sine plate and collimate off it. You will get a very good indication of how accurate your V block is. Calibrate your sine plate with zero degrees (ie no blocks), Any lapped surface will provide a good enough reflection to do that. Gauge blocks make great mirrors in fact. Do you think the grooves were strictly necessary when using such fine abrasive? My understanding they're more for coarse abrasive so the excess that doesn't charge the lap has somewhere to go. Not such a factor with fine abrasive. One thing to mention to your viewers is to grind the lap before changing to a finer abrasive. The lap is charged and that layer needs to be removed before going finer. Your surface grinder is sensational and you do beautiful grinding. I've never seen that saw before. A very nice piece of kit, thanks for showing us that.

MUCH better than watching grass grow, although trucks rusting might give it a run for the money...just kidding, great video. Thanks, as always.

You just have a way of moving on' fantastic show👍👍👍👍👍

This video isn't boring, it's lapping *badum-ts*

I have seen many, many machines, but it is my first time I see a machine like this!!! Thank you for Sharing :) I just love your work. Have a very good year and Hope to see lots and lots of video from you. Lots of love from Iran....:)

Thanks, I will look forward to more lapping videos. I think you get monochromatic light out of any LED. You might using and LED flashlight and see what happens. Could save the rest of us a bundle for a light source..

Outstanding Tom! 😃👍

19:18 OMFG and then laughed so hard i choked on my spit!

Nice Tom, the only things I have lapped are valves! Using what would amount to the equivalent of 32 grit paper! Enjoyed.

CALGON, take me away! Awesome video. Thanks for the informative video!

Great video and very informative. Thanks Tom.

Oxtool you learn something new every day

I love these old school approaches. You can actually see the physics principles at work.

Hi Tom, Very interesting subject... Enjoyed... ;) Cheers, Pierre

Great video. You are a consummate professional. Thank you.

wow, learn something new every day. And I thought my shiny finish on my surface ground drill press was flat. lol

really interesting Tom thanks Will

THANKS TOM VERY HELPFUL

You taught me something again. Thanks.

If you have one, try the optical flat with an ordinary laser pointer; those should be monochromatic. :)

Great stuff Tom. Thanks.

After grinding use paper on a flat lap or granite with diamond paste then final lap with Happich (pink) semi chrome polish.

Very interesting Tom, great content.

nice work leaned something new thanks

Very interesting! Thanks for the education... Fred

Thanks for sharing!

great video i have learn alot thanks.,,.keep it up

diffraction pattern or grating is the term for the lines shown on the optical flat.

A more than interesting video Tom. Information and especially videos about precision lapping is tough to find. Since I've never lapped anything even close to high precision this is simply passing along a technique I've seen mentioned in Guy Lautard's second? Bedside Reader book. They mentioned how to get surfaces lapped as parallel as possible while using a lapping plate by weighting the part at the high side so it gets lapped much quicker at that area and into being parallel. On smaller parts the magnetic base from an indicator stand and without the vertical rod might be enough to weight bias the part. But it was something I've always remembered given the accuracy they were trying for. I'd be surprised if that's anything new to you though.

Hey Tom, when making a lap out of cast iron can you use any old grade of cast iron or is there one that does a better job? i've been seeing several different grades of cast iron in german ebay and have worked with some really bizarre stuff and so it would be good to know if there is any discernible difference a guy needs to watch out for? cheers mike

Well, that just blew my friggin mind

Very interesting. I have a lap I've never used. I think I'll have to order some abrasives. Now, how about a video on testing the ground and lapped block?(amateur here) The geometry makes it interesting. Parallelism of both sides of the base, parallelism and centering of the axis of the v to the sides of the base, parallelism of the axis of the V to the base, actual angle of each side of the V away from the centerline plane down the length of the V, etc.

Good one, learned something.

thanx Tom !!!