Confessions of a surface plate abuser

[@jacquessmit115]

Just a Tip from Africa, we do not have the facilities to have tools delivered to our door, so as a surface plate alternative we use a good piece of plate glass, fairly thick, I have mine set in a recessed block of wood, so it is safer, and I keep in in the corner of my shop. I have cleaned some motorcycle clutch covers that leaked because it was ever so slightly warped, some high grit on the glass and rub it in a circular motion managed to bring the mating surfaces in the same plane, and hey presto, the cover can be put back on and no oil leaks. Replace or turn the glass when you suspect low spots are developing. I check it by using a straight edge and feeler gauges. Obviously do not drop the work piece on the glass.

[@KaimasterXD]

Glas or even better mirrors. If a mirror is not very flat the reflection gets warped

[@WireWeHere]

You must have some beautiful night skies so if you happen to have a couple more thick glass blanks, about the size of an 33⅓ LP record you're on your way to a nice telescope....by weight at least. That size works great and gets your arms in shape for serious sanding. Just a thought... I forgot to mention the search parameters: "John Dobson making your own reflector telescope". He's the solo version of a reflector telescope collective knowledge database. A natural guide. Cheers.

[@melgross]

A good quality glass plate 1/2” or thicker has been a way to do this for a pretty long time. I use one myself.

[@BedroomMachinist]

I mean I don't know how expensive your glass is but a grade b surface plate like 24 x 24 is only 100-200 us dollars.and that's for large parts you can pickup a used starrett toolmakers flat out of class A Pink granite that is 8"x12" or 12"x16" for sometimes like 50-150 bucks.

[@rameezsheikh7576]

What on your name ? 🤣​@@BedroomMachinist

[@christophermikesell5722]

When I worked in the grind department at a company in Bad Axe, Michigan, we had one of these in each work area. They are very handy for cleaning up parts after they return from heat treat. We would rub the parts before measuring them on the plate and they thus saved wear on the plate (from the grit and residue which got stuck to the parts during heat treat, and which would have otherwise been rubbed on the plate and machine chuck) and made the parts stick much better to the chuck during the first cleanup. You could also easily see the locations of any burrs (and remove them) as well as the contact pattern which gave an indication of how the parts had warped in heat treat. They also put one at each work station in the mill department, where they could use them to knock off unseen burrs very rapidly. All of them were similar to yours, and used a full sized disk grinder pad, but had a 3/8" thick steel base which was Blanchard ground on both sides. They were heavy enough not to shift during vigorous scrubbing and yet light enough to pick up and move. At a cost of less than $300 in material, tooling, and time, I estimate that these would be cost justified in under a 40 hour work week for one person in a serious shop doing short production cnc machining and grind work. These were one of the most practical productivity-boosting hand tools in that shop.

[@GregsGarage]

I love watching these kinds of projects... No blue print needed, just dig in and get it done... I'm learning a TON from seeing you and other machinists work. Thanks for bringing us along.

[@ianrobinson509]

Interesting to see rotary grinding. What did surprise me is that you didn't bother to bore the center hole when on the lathe to bring it truly concentric. Useful for other operations.

[@RyJones]

Robin and Tom, saving the world one surface plate at a time!

[@nottelling6598]

22:13 That's the kind of thing I love doing. Taking a look at the cast-offs and offcuts and imagining what you can use them for is more fun than doing that with a solid piece. There's just a hint of a challenge to it, but no real pressure other than the desire to not waste.

[@ensen89]

When a surface plate wears a hollow it can easily be filled up again with some sharpie! :D

[@railgap]

Or Bondo. **ducks and runs**

[@jovanivaldez924]

@@railgap 🔫

[@jerrylong381]

Yeah, I have too confess too. I've done the same. I'm a maintenance machinest in a plastics factory. A couple months back I came into the shop, and the night shift mechanic had been working on some feed chains for a thermoforming machine and had used our 24x36 B Grade surface plate to set the chain on to swage the pins back into about 6 links. Needless to say, there are little pairs of chips that perfectly match #60 chain all over the plate. I lost my mind, chewed his ass for a while and post a sign on the plate stating "THIS IS NOT AN ANVIL KEEP YOUR GODDAMN HAMMERS AWAY FROM HERE" The sad part is we have two 4'x8'x 3/4" steel work tables one only 4 ft from where he did this. AAAAAAAAA!HHH!A!HG!HAHA!!!AAGAA!!!

[@KISSMYACE3203]

Sounds like my coworker, and actually, a lot of people in general. I swear they look for the nearest thing to get a job accomplished, whether it be my tools, table etc. rather than doing things properly. Drives me up the wall. I use filing cabinets as toolboxes, they're free :D, so I can't lock my stuff up. Ended up leaving different large notes in sharpie in all the drawers along the lines of, "Stay the fuck out of my tools and destroy your own garbage." My dad told me, "I don't use your shit, because I don't want you using mine." It'd be one thing if people were respectful, but in their eyes, a micrometer is just as good a c-clamp as a wrench is a hammer.

[@samrodian919]

@@KISSMYACE3203 buy yourself some hasp and staples and padlocks and lock your filing cabinets that way when you are off shift lol. I certainly would or take the vulnerable tools like mics and such home every night lol

[@SuperAWaC]

millwrights gonna millwright

[@spehropefhany]

And people wonder why there is a cage in the middle of a shop.

[@mor4y]

@@spehropefhany for putting the apprentice in after the 20th stupid question of the day? :)

[@mp6756]

I really like the 4 jaw adjustment bolt setup for keeping the part parallel. I'm so envious of your wide variety of equipment and setup gadgets. I am living vicariously through your KZbin videos thanks

[@moms762]

When you peeled the backing off the paper, and then raised it up, it appeared to me that something had fallen off of the paper and was on the disc when you stuck the paper down.

[@pedrobatista4439]

"...and if we can't, we put a groove in the middle." Classic. 🤣🤣🤣

[@paulwomack5866]

Actually, lots of wooden chopping boards for kitchen use have a nice big groove round the middle, to act as a grip for lifting. So a large groove might save the work of drilling and tapping, and fitting those feet. :-)

[@Gabriel-bk1hk]

@@paulwomack5866 ⁷7

[@Gabriel-bk1hk]

K7 I 09pl .

[@geckoproductions4128]

Really enjoyed this video Tom. I will probably never make this surface plate, but the little tips and tricks you through in almost as an aside are extremely helpful to me. Thank you

[@bradthayer6782]

“Hi, I’m Tom.” “Hi Tom!” “I’m a surface plate abuser. I’ve been clean for 2 days.” (Applause)

[@genixia]

Step 8. Made a list of all persons we had harmed, and became willing to make amends to them all. Step 9. Made direct amends to such people wherever possible, except when to do so would injure them or others I think that means just buying more toys from Mr Starrett, right? A direct confession might cause emotional injury.

[@jakeqwaninne8502]

oh my god,,,, AA alone kept me from ever wanting to drive when i drink,,,, i hated that whole cult

[@williamsquires3070]

Hi Tom. A thought. After removing the material from one side (where the flat is), I’d flip it over, then make a very light pass with that X-acto blade to form a crease, then fold the sticky part of the abrasive disk over the other flat and trim the bottom. Now you can sand either one or both surfaces of a part that has an internal 90-degree angle (like an “L”-shaped piece.) 😎

[@unherolike]

Oxtools: "That is as close as we will ever get" Abom: "Lets spend another 30 minutes centering this piece up so its dead on with no runout" AvE: "It runs about 2thou off.....Good enough for the girls I go out with." The Machinist world in 3 different takes.

[@QueernMental]

Pakistani truck channel: "ਹਥੌੜਾ ਚਪਟਾ ਹੈ"

[@whatelseison8970]

What? No love for dear Old Tony? For shame.

[@BlackSoap361]

@@whatelseison8970 ToT: “that worked out closer than I expected.”

[@melgross]

Yeah, we could have done without that last one.

[@WillowEpp]

The first step is admitting you have a problem. Good on you for building a tool to help.

[@dougvanallen2212]

Tom spreading your knowledge to all of us is really greatly appreciated more than you know thank you very much

[@shonuffisthemaster]

the best i have found on my cheap dedicated sanding reference plate is using 3m microfinishing film (or any mylar based sandpaper), wash the plate well, then put the paper down on the wet plate and squeege out the water from under the paper with a plastic card type squeege (very important) the paper is suctioned to the plate by surface tension, and not only does this keep the paper from moving and causing more wear on the plate, it keeps it quite flat to the plate so you dont have the leading edge of your part hit the paper wave and create a convex surface. work the part wet on the paper (not too much water or you will float the paper) the mylar based stuff dosent curl up like paper based sandpaper so you can re use it untill its dull. the 3m stuff is much more precision graded than regular sandpaper, and you can get it from 30 micron down to .1 micron.

[@colinosborne3877]

You yanks seem to have every tool for every occasion. Here in the UK in my shop I dont have the room. When I was an apprentice, I would have scraped this to blue. Now that was skill!

[@fsj197811]

Nice little project. Thanks for sharing.

[@byronwatkins2565]

When applying the paper, I would align the half that has the backing on it so it will slide and then stick it from the center outward.

[@DaleKallio-jk9wo]

Nice demo of finding median for an out of round condition😊 2 dimensions for datum👍🏻13:10. Are those flex bars and you're adjusting nut height from face to level?

[@DudleyToolwright]

Always informative and interesting. Never stop Tom. It was great seeing you at the Bash.

[@philippzimmermann6027]

Ahh sipping your coffee on a sunday morning while watching a new ox tools video is just great. Thanks for the great video Tom!

[@ElectricGears]

You could make some magnetic feet that would be just a disk magnet with a steel post and self adhesive rubber pad. That would allow you to put a different grit of paper on the other side of the disk and just flip the feet to the other side when necessary.

[@RobertSeviour1]

Thanks for a really wonderful tutorial; this is how to make educational videos. Seeing you work on the lathe took me back to the 16 year old me, mid last century.

[@zexsrah5836]

Really cool. I have some surface ground 1inch plates, in 2 sizes in length. I use them for the same application. When they become compromised I regrind them and good to go. Also they serve as a good reference surface for flatness . good job tom!!!!

[@BedsitBob]

When you were turning the OD, and counting down to the chuck jaws, I had visions of Captain Ramius, counting to the turn in the caves.

[@TheAyrCaveShop]

Turned out great, nice project....I've been using a pastry makers marble rolling plate with the same 12" sanding disks. It's surprisingly flat and water proof for wet sanding. Enjoyed...thanks Tom !

[@agentstaple1]

I've got an old granite chessboard that I've long since lost the pieces for. The back of that is pretty flat, good enough for chisels anyway

[@samdude1953]

I like how Tom used the correct form of "jury rig." A lot of people say jerry rig, perhaps mixing jury rig and jerry built. The two terms have nearly opposite meanings. Good on you, Tom!

[@TabletopMachineShop]

You should make a custom "Mr. Bozo" shop magnet that starts out completely bald and grows hair with steel chips.

[@williamsquires3070]

That’s just evil! 🤣

[@krugtech]

I do emergency machine repair. When a plant full of workers are standing around waiting on me to get a bottleneck fixed, all tools are sacrificial. I am not proud of that. I'm proud of the reputation, respect and compensation I receive.

[@krazziee2000]

Nice new tool for the shop, good to see you again,,

[@wolfitirol8347]

While building my diy surface grinder I have already 150+ hours on it but I'm always watching your videos beside so it will take ages to finish the project 😂😂😂 I love your videos you are one of the best metal youtubers 👍👍🤪 With Rob, Adam,Toni,Joe and Stefan you're the creme de la creme 👍👍👍👏👏👏

[@cschwad559]

Boy, Tom, it’s good to see some old fashioned lathe work on your show again.

[@madscientist5969]

YES!!!!!!!

[@tced2858]

Tom I like your idea with the Walmart bamboo drawer organizer...got one in my kitchen just like..! Good video...as always..!

[@kylejacobs1247]

Was anyone else going crazy as he stuck the sand paper down that there was a giant speck of dust that had settled on the plate and is now a class A scratchmaker?

[@AndySomogyi]

I do the exact same thing with my little 4x6 saw when cutting at an angle, pushing on the side of the blade until it catches. I’m not a pro so wasn’t sure if that was a pretty sketchy thing to do, but I feel a lot better seeing a pro like you do the same thing.

[@blipblip88]

Your demonstrate good quality control in your shop-good work!

[@billchiasson2019]

Great video! Always a joy to watch! Guys out there don’t get to caught up on the size of the plate, they make all kinds of diameter sanding paper to fit what ever you find for a disc.

[@rgmoore]

Tom, this turned out great! My inner voice is saying 3 points of contact for the feet but I wonder if that might cause tipping at the non-supported edges. Anyway, thanks for sharing!

[@madscientist5969]

Thanks Tom...I really liked this video. The straight edges on the plate are money! I'm gonna head off to my local machine shop to see if they can 'doit toit' for me. I think it will be great for for my little hobby wood shop.sharpening...and save my granite surface plate. I guess a thick slab of float glass could work also if I was gonna only sharpen wood cutting tools...but I think the steel plate has more usefulness overall..

[@charlescartwright6367]

Aloha Tom, I'm starting to worry about ME, I have a project set up in the mill that I left last night and here I set on a Saturday morning watching YOU work???? I do enjoy you talking through your thought process as I most always pickup on a tidbit of information here and there. Mahalo for your time and keep them coming.

[@amundsen575]

nice touch with the flats. I got some sink drops from a granite counter top shop

[@1crazypj]

Find a place that does stone/granite/marble countertops, they cut out a piece for sink to fit into. Usually pretty close to flat and less than $20.00 as an off-cut. Pretty sure it would cost way more than that just to ship a large chunk of cast iron? (plus whatever it costs for a piece the size you had?)

[@africanelectron751]

Damm that's a smart idea.... Allso tombstone makers are worth a visit.

[@1crazypj]

@@africanelectron751 .as long as it isn't recycled from the cemetery ;o)

[@WireWeHere]

At 5 minutes: putting the needle at 3 o'clock gets its movement inline with reality. Just a little something to help anyone wrapping their head around the variables.

[@Scribe3168]

That’s a tip!

[@tacitus101010]

I absolutely love that wheel centering tool!

[@briggsbughouses6291]

Thanks for putting that blast shield up, I didn't have my eye protection at hand when I clicked on your vid!

[@farmalltomf]

Nice project and good advice Tom, however, early on, that off-center hole drives me nuts! LOL. Great video. Well played.

[@KenGutkowski]

I thought I was the only one. It makes your machinist senses tingle, and not in a good way!!! HAHAHAAAA

[@najroe]

Was expecting him to machine it at least some

[@KeithOlson]

#same

[@Hephera]

if you make yourself some little copper covers that wrap around the chuck jaws (ie just use a longer strip of copper and bend it around the jaw) you can slip them over the jaws and not have to worry about having copper shims slip out when you back the jaws off too much while dialing in the part

[@PlayerSalt]

Ive seen this done with pieces of glass a lot , exactly how flat is glass , not sure if you have ever done a video on it but id be interested

[@Broken_Yugo]

Depends a lot on your glass and definition of flat.

[@samantoniak1657]

Really depends on the thickness of the glass. It is brittle, but not very stiff. If you have a thin piece of glass on a not flat surface it wont be flat.

[@Si-Al-Ti]

Common among woodworkers on a budget to sharpen their tools on plate glass with abrasive paper

[@johnmccallum8512]

@@Si-Al-Ti Also an old dodge in vintage engines when you want a reasonabley flat cylinder to head fit. You want apiece about 12mm/1/2" thick at least. Where you get it thats another story.

[@treatch3]

@@Si-Al-Ti check Lee Valley Tools has a glass lapping plate for 20 bucks....Canadian

[@shawnhuk]

The only downside here is, that hunk of cast would be near $300 or more, up here in Ontario in my neck of the woods. I tried to get my metal supplier to bring in a 2” x 2” x 18” chunk of cast so I could make a straight edge and it was going to be $130...

[@chronokoks]

300? Oh god.. it would be cheaper to buy old cast iron brake discs (every scrap yard has tons of them), melt them in a 200 dollar furnace (old tank, ceramic cotton, firebricks, fireproof mortar, propane + diy venturi burner) and pour into a very crude sand mould (open top.. just a bunch of wet sand with a circular imprint)

[@oxtoolco]

A clever guy might take a look at some cast iron free weights at the local sporting goods store..... Cheers, Tom

[@shawnhuk]

@@oxtoolco - I've done that. What a horrible experience! I made a back plate for a Pratt Burnard collet chuck from a dumbbell. Full of voids, weird chunks that would break the brazed tool bit, it smelled weird?! I'll be honest, I was warned about using free weights as a source of cast iron, but I did it anyways. I've heard them once described as compressed chinese street grime.... I've also heard chinese inserts described the same way. Lol.

[@oxtoolco]

@@shawnhuk You have discovered a new alloy! "CCSG" iron, Dumb bell grade. Got a good laugh out of that one. Cheers, Tom

[@chrismorris8695]

If you can find some old York plates, they used to machine the backs of these plates to achieve closer weight tolerances. The set that I had (and sold to fit my lathe and mill in the garages) looked beautiful. There were no voids or irregularities in the machined back side.

[@robboz85]

Learn something new every time I watch your videos. @ 8:00 I didn't know avocado pits were magnetic

[@bkoholliston]

Nice video! A lot of woodchucks use sandpaper on glass as a flat surface for sharpening. You need a fairly thick piece of glass and many folks say you need "float glass" which is produced by flowing molten glass over a molten tin bath. I have used regular window pane glass and I think it is OK, but not surface plate accurate. Woodchuck stores also sell granite surface plates to use as sharpening platens with sandpaper. MDF from the big box hardware store is also remarkably flat and works OK, but does degrade over time.

[@Chris-bg8mk]

Amazing at 2:50 watching the cast iron change color! Automatic white balance artifact?

[@OtherDalfite]

McMaster-Carr is so awesome. They offer free CAD models that I use at my job all the time to plan assemblies. Great company.

[@jaecenwhite2590]

Some granite floor tiles at big box stores are extremely flat- I use one of those for most sanding if I don’t need greater precision

[@waynep343]

i used to cut a lot of brake drums and rotors on various drum and rotor lathes.. i always tried to have some inch and a half disposable natural bristle wooden handle brushes next to the lathe.. i would rest the side of the bristles on the cutting tip.. so it deflected the chips downward.. nylon bristles just melted as did plastic handles sometimes. it does block the view.. but i would rather not have chips everywhere .

[@ITzSmores]

The gloves being worn while at the bandsaw made everyone at OSHA quit

[@DroneFragger]

just gotta buy gloves that tear more readibly than a human finger joint

[@jeromeprater183]

Great job! As a suggestion, I would have J.B. Welded a slightly undersize pin either before turning or roto-grinding. This would help prevent snagging on smaller parts or parts with sharp corners.

[@RRINTHESHOP]

Does this plate come in a set of 16 or just 8. Very nice.

[@FinnoUgricMachining]

You can clean the chuck by sucking with Your shop vac from the back of the lathe and then using a bottle brush to clean the jaw threads. Cleans the jaws and their threads really well unless You let go the bottle brush into the shop vac.

[@Rsama60]

Nice project. On compressed air on machines. During my apprenticeship as a tool and die maker back in the 70‘s one thing we got hammered into our heads. Never ever use compressed air to clean precision machinery. During the year I worked in the mold shop we had the same rule.

[@jerseyjoe2684]

Lol I knew where you were going with this before you said it. Now I'll watch the rest of the video.

[@KISSMYACE3203]

I will have to call you out on not cleaning off the plate again before putting the disc on, Fresh abrasives are notorious for leaving behind particles, especially laying down as it was. Other than that, great video as always, you're like the mentor I've never met.

[@braingrenade]

Starting @0:47 is that holder for your test indicator made by you or can I get one of those somewhere? I'm a calibration tech and that would be really nice for holding test indicators since I use gage blocks to cal with.

[@Evergreen1400]

Cool video this is the 1st video of yours I’ve seen I like your work and personality you seem very easy to get along with so I’ll be checking out more of your videos.

[@brushbros]

The irregular sanding pattern on the sand paper shows that it is less flat than the base plate by orders of magnitude. You need to use diamond paste instead.

[@rc166honda]

As ever, lovely work. Thank you Tom

[@ronwhittaker6317]

never get tired of chips flying sawdust production. or filings. call me crazy. for now, I live via youtube machinist I don't have a problem watching each and every operation from start to finish. i like every detail so that I can know for sure how the job is done.

[@cliffordfender1159]

Tom, I always marvel at your saw ! Cheers, Cliff

[@dangerrangerlstc]

Question from a non-machinist. Wood workers and cabinet makers often have centralized vacuum systems with collection pipes at every machine. Why not so much with machinists? Seems like some sort of flexible vacuum nozzle rigged up next to the cutter would collect all the dust and chips where they're being formed instead of flying everywhere.

[@sandmanbub]

A little piece of tape can make removing an adhesive backing much easier. Enjoyed watching your work, thank you.

[@diet-water]

Never knew about this. We always used a parallel bit of C250 Aluminium and double side sticky tape some emry tape to the back of it

[@nestorknoxs3795]

Heyyyy!!! I'm new to your channel. Nice work and I enjoyed the video. Down to earth, little humor and right to the point!!! I'll be here for awhile!!💪🏻👍🏻

[@TheKnacklersWorkshop]

Hi Tom, A job well done... Thank you for sharing... Take care Paul,,

[@blauesKopftuch]

41:01 get yourself an eraser, the ones for pencil on paper, but a big one (usually have a print on it "for big mistakes"). They work like a charm for cleaning sandpaper / (diamond)grindingstones, produce way less smearing compared to those un-vulcanized latex-rubbersticks some woodworkers use for their beltsander and you don't spread so much dust in your workshop. (You still need the brush for the finer eraser crumbs, but they are significantly larger and won't fly a fraction of the distance)

[@SliverLIVE]

Hey, i grind aluminium with grain alcohol (spiritus), makes the job much easier and the paper is not smearing up. You can also create a rotating plate, also much easier to grind with. :P Greetings from germany.

[@whatelseison8970]

Ah yes, the old spiritus makes all sorts of jobs much easier. Just don't let the boss find out. 😉

[@bkailua1224]

Pretty nice plate, I live where cast Iron likes to turn into Iron Oxide in 3 nano seconds. Shars $30 looks like a good idea.

[@TrPrecisionMachining]

very very good video..thanks for your time

[@thrownchance]

it kinda bothers me, that the hole is not in the centre.

[@buckinthetree1233]

It bothers me also. I think if you're sanding any small parts that go over that hole the sandpaper is going to sag into the hole causing an issue. I think I would have drilled it to a nominal size, tapped it, loctited a bolt in, and then faced it off flush. Tom is a lot smarter than I am, and he knows what he's going to be using this for so I'm sure if it were going to be a problem for him, he would have fixed it.

[@BluesDoctor]

Another great and enjoyable project to watch. Thanks!

[@archangel20031]

You mean the CENTER?

[@genixia]

@@archangel20031 I'd imagine that he meant the centre, as spelled by the originators of the English language, the English, and most non-US countries where English is used as the first language, including Canada, Australia and India (populations totalling ~1750 Million). You chose to ignore all the interesting things that could be written about this video, and instead went with pedantism.

[@genixia]

@@buckinthetree1233 I'd only consider that if I had a cast iron bolt. With any other metal the disparity in thermal expansion rates will exacerbate flatness errors in the center. A hole will always be a hole, easily noticeable and avoided when sanding small parts, completely bridged and mostly irrelevant when sanding larger parts. A plate containing a faced-off bolt of steel would only be flat when at the exact temperature that the plate was at during final grind. If the plate was warmer than that then I think you'd end up with a high spot where the bolt was, and another high concentric ring where the iron deformed upwards under radial pressure. That said, I'm not sure that the effect would be of the order of magnitude to be of much worry considering the tolerances of the disc and adhesive thicknesses. I am surprised that Tom didn't either re-cut the hole larger to be concentric, or center on it during lathing. That's the sort of thing that would bug me forever. I await the future video where he forgets that it's off-center and Bozos somehow.

[@yvesdesrosiers2396]

You could use a crepe block to clean your abrasive. It helps clear between the grains and extends the life of the abrasive. Just a thought.

An incredible amount of work to make something you could have just purchased.

[@WireWeHere]

A starter guide bearing project for your bandsaw. One that pops out the way...or a brush handle bearing...

[@Orxenhorf]

Or, to piss off as many machinists as possible, but be fine for almost every other use.... go buy a 8 or 12 inch granite flooring tile from the local big box store.

[@genixia]

Be careful though - they are thin enough to bend and take on the shape of the underlying surface. A better choice is to find a small custom kitchen countertop supplier. Their workshop probably has off-cuts piled up in the yard awaiting disposal, most of which have effectively zero value in their market. You'll likely find a suitable sized piece of 1-1.5" thick granite with better stiffness and flatness than the floor tile. Another potential source is countertop rip-outs on Craigslist. Be aware that countertops aren't precision-ground and the edges of abutting slabs are sometimes polished in-situ to reduce lippage, so they aren't suitable for precision measurements. With a little effort you should be able to find something usable for sanding though, and if you got three pieces and lapped them together with diamond paste you could end up with something better than anything not sold as a precision surface plate. At some point though you need to remember that a Shars Grade B 9"x12"x2" surface plate is only $30, and a 12"x18"x3" only $50.

[@gearloose703]

How about a manhole cover?

[@thebad300]

thick glass plate

[@Tsamokie]

@@thebad300 Yes. 0.5" plate glass is a good substitute.

[@vincentrobinette1507]

A tile like that won't be flat enough, for precision work. a machined plate like this really is the ideal thing.

[@billdlv]

Nice job Tom, looks very useful with the 2 straight edges. I'm wondering if a smaller 6" version might be useful the sandpaper for that size is readily available. Maybe even used like a bench stone that stays flat unlike regular stones?

[@MrYukon2010]

Hi Tom, first I want to say I admire your skills and love your enthousiasm showing how things are done. My question is (and I have to admit I know less than nothing about designing, machining etc.) , with all that precision you are working with, does temperature play a role? I mean, when you measure metal, according to my physic teachers, metal usually changes volume when tempreture changes . Does this influence your mesurements, and if so, how do you correct that? Again, I have absolutely no experience with this, I never even met a CNC machine. Finally, I am fascinated by what you show on your channels. You got a new subscriber.

[@geraldsylvestre535]

I trully hope none of my metrology student EVER treat a surface plate that way!! I wonder if I should report this video to the admins !!! Sand paper on a surface plate!!! there is a special place for people like you in the underworld :)

[@jlucasound]

Awesome video! I learned a boatload! Thank You!

[@jonanderson5137]

Honestly, I was expecting a pressfit pin for the center of that plate before finishing.

[@samrodian919]

Or NOT centre of the plate! Lol

[@jlucasound]

Yes!

[@74KU]

God at least a bodgy plug weld before it was all ground back to dimension!

[@0verboosted]

Before Tom even finished I knew he was going to mention Robin!

[@garymucher9590]

Nice plate sanding idea. Where did you get the metal from to make it? Thumbs Up!

[@AmateurRedneckWorkshop]

Very well done as usual. Now I know what to do with all those 12" cast iron cutoffs that I don't have.

[@notsofresh8563]

Tom, There is some kind of ships wheel behind you at the beginning, What is that for? It looks like it would work pretty good on an etching press...

[@1arm_658]

What is the tolerance of the adhesive on the back side of that paper?

[@michaelvogels9905]

at 36:45 could the sparks spraying over the 'finished' portion affect the surface?

[@djvanzz]

ive been told put saran wrap or package cling wrap on the surface plate when sanding

[@ChrisHarris4U]

I am curious what goes on in the minds of people who give this a thumbs down 😳. You make great videos! 👍👍

[@tomstech4390]

Nobody disliked the video, people just dislike theyre not as good or don't have the facilities. But they like the video ;-)

[@ALSomthin]

Yup a piece of Blanchard ground steel plate or a cast iron plate like an old table saw is a good thing fot using abrasives on.

[@tsfarken]

Good tip with the brush handle.