Squareness Comparator

after a shop for the longest time I wanted a squareness carburetor to measure the squareness of work pieces on the surface plate and I was thinking about a good design for quite some time and due to a post on Instagram I got a good inspiration on a design that looked very similar to this one and I modified it slightly and I built it and that's the result that's my squareness comp area has base width 4 feet the hardened bumper piece with the large radius here indicator hold up here with the fine adjustment and spring steel flexor in here is an hinge and it holds my two thousand seven millimeter more they'll test indicator unfortunately I lost a lot of video footage especially that footage when I machine the base due to stupidity of mine I copied the files back and forth between card PC different folders external hard drive and I don't find it anymore but I have some footage left and I will try to show you at least some of the parts as they were made so hope you can still enjoy this video and sorry net once if it looks said if it's a bit out of order so have fun okay this is how the squareness cooperator looks right now I have to base piece of tool steel I have four balls pressed into the base surface ground flat so we have four hardened feet and yes I know Surrey feet are more stable than four but so if I put three feet in here it's it's very easy to tip over the axe between the three points and I don't want that so I went with four and as they are surface ground in one setup they are all the same height and I cannot measure any tipping on the surface plate so spare me that comment please laughter clamp here which jet this is a piece of hardened aground linear shafting have the clamp here board to a close fit I reduce the material cross section here and here by putting this radius in here so the clamp verbs very easily I can fact they even can lock it by just pressing on here with my fingers and it's a two-part design I have to clamp and the indicator hold as a two parter that's there is a split line and I have a piece of spring steel flaps brings your one millimeter thickness as a hinge I have an adjustment screw here and the screwdriver so we can very finely adjust the dial test indicator the holder for the dial test indicator is i milled above tail 60-degree dovetail 5 millimeter and split that and it's also clamp with a single screw that can hold my regular dial test indicators first I'm going to make some proper screws thumb screws for clamping at adjustment let's take this guy off here the clamp off and I have a lot of photographs that out with saw we've a write-up that I'll link to in the description let's take off be the indicator holder screw down with four or with two three millimeter screws and as you can see I drilled also into this piece and pressed in a ball bearing ball and then surface ground it that gave me a hardened wear pet or sliding surface for the adjustment screw as I don't have to harden the whole part just drill one or two tenth of a millimeter undersized press in the bearing ball with some Loctite and the surface grinded flat or leave it a slightly proud like I did of course I need to make a proper screw the the final adjustment screw will have a bearing ball in the center so we have hardened and ground running and hardened Bank ground and this will give me a very smooth adjustment action not like the scrappy screw on the crown surface this is not very not very good the adjustment screw is a six millimeter threat I will also put the my hand sketches in the in the link with the description of on the photos but I have no proper drawings on this project only the hand sketches so if you want to build something like this yourself you have to either come up with your own design or as I copy a design or work with the hand sketches if you want so that's current current state of progress now we will proceed on okay the last piece we need for our squareness cooperator is the bumper which goes here little drill tap two holes into this face so we can screw it on here and I like the bumper design with a big radius and we're going to mill it out of a piece of tool steel we'll have an L cross-section L shape and have a big radius mill down to it I have to do the math which radius will end up with the Moodle harden it then we will grind it and we'll heart mill the radius just to clean it up I have no way to grind such a big radius on my surface grinder properly I know that you can side wheel such a radius freehand with the magnet turned off but I think I prefer hard milling and then some hand work with stones to even it out so let's go to a milling machine take this piece of 128 to steel and make some chips and we start machining the bumper by screwing up the piece of tooth filled with a rather small six moon with carbide end mill just serve facing down both sides both stock up sides the other two surfaces are already pre ground as it is pre ground tool steel and I prefer the smaller angles for such tough materials as they don't tend to put as much strain on the machine as a big cutter would do of course we do all the machining dry except for squaring up the ends because I'm using a 8 millimeter high speed steel end mill and I don't want to run that without any lubrication of tool steel so I'm using a little bit of cutting oil deburring the part I'm of the mindset to not chamfer the edges while you do machining only remove the burrs by by moving the part over some Emery cloth I have Emery cloth double stick tape to a old parallel that's what I use for deburring and roughing out the l-shape again with the six millimeter carbide end mill and I'm using some compressed air to get away the chips I'm running at 1,000 rpm and about one millimeter one and a half moving a step over with full depth of cut which is about 10 or 12 millimeters and this is very easy on the tool you don't you use the whole length of the flutes and that's how you get more life out of an end mill and taking the finishing cut that's time to clean up the mill and the real advantage when you do dry machining is that you can just use your shop vac suck up all the chips and you're good for the next setup within a few seconds doesn't really take much and again deburring the park not chamfering any of the edges right now just knocking down the birth I'm referring to the mechanical metal Trades handbook to figure out the radius of the bumper bit of math but before a machine radius I'm drilling the mounting holes into the bumper spot drilling drilling and chamfering the holes I get asked a lot what cutting oil I'm using I use whatever I can get my hands on and right now I'm using this crong crong oil canning the rotary table ready on the table to do some radius milling and always careful when you set up machine tools not to dent your machines table or the tooling itself careful lift it slide it in place and are setting up for the radius milling and have to park back there on a parallel I'll slightly tucked down with one strap clamp and now I'm using a stack of gauge blocks to get the right distance to the center of the rotary table I have a 6mm of the high speed steel blank in the collet in the center of the rotary table and that's my reference point for aligning the part I'm using a square to get the part into the right orientation in the other direction that's a bit fiddly but it doesn't need to be super accurate for this purpose and attaching a set second strap clamp tucking it down and good to go very easy setup four millimeter carbide end mill and cutting the radius and about 0.5 millimeter increments I don't want to over strain the setup and I didn't mill all the way through I left about point 1 million of material in the end so I don't run into danger of machining into my parallels and that's how the part looks right now we have the remaining material still on there clean off the rotary table a little bit of compressed air and tear down the setup that's our part and we can easily break off the remaining material and yeah that's radius okay oh very with the bench wash and I'm using some hand files to clean up the radius before I harden the parts just just a fine triangular file hitting up most of the milling marks and look at the mess on my bench at the finished part and now it needs to be hardened and the great irony is I have a oven and the very kind viewer sent me a your firm temperature controller it's right there sitting already in a box but I didn't have time to wire it up and make it running so for this part I have to resort to the torch running my small oxyfuel torch with the biggest tip I have to harden apart it's absolutely not ideal for this part the part is all almost too big to be hard with this torch but it worked out in the end took quite some time to get enough heat into the part you can see I'm slowly heating it up to a cherry red temperature or color and ask this isn't this 2080 to fuel this air Hornung you can air harden or oil harm it and I decided to try air Horning this time so going away with torch and I pick up my air gun and I'm cooling down the part with air this should be enough to let it jump to a significant hardness so the first for me I never tried this before so we'll see how it works out okay you saw me just flame hardening the part and I wanted to know about the hardness at least approximately and I have a set of su bows and hardness testing files I ordered these directly in Japan because they're cheaper that way you can find them on ebay when you search that name made in Japan and Tomlin already showed them so I won't go into great detail but they are quite need to set of six files and I range from 65 Rockwell hardness see that's hardness with a cone 65 down to 40 and you use them to test the hardness of the work piece start with the 65 HRC file and you just press down on the part and see if it grabs you don't take big filing strokes with this just look if it if it grabs and if it grabs like the 65 to take the next softer file 60 the scraps to 55 huh barely are almost slipping 55 this is 50 the no way doesn't grab at all just scratches the scaling so 50 slips 55 grabs so hard ass between 55 and 50 without on tempering annealing so I won't do anything to the hardness of the steel the flame hardening is not the most ideal choice for this part but I decided to go with it instead of firing up the oven and waiting one hour until it's up to temperature so now as the part is hard booth again can remove the scaling I removed the scaling before grinding because it tends to glaze up the wheel okay we row at the surface grinder and I'm just touching up all the surfaces slightly with an 80 grit alumina oxide wheel to get the part after hardening nice and square or back square again it was square when i milled it but hoarding of course slightly warped it and I'm not too fuzzy about the dimensions of this part I just one to be cleaned up and nice and square but even that would not really matter but my personal OCD doesn't allow for parts that are out of square so cleaning it up so and I'm using some oil while for grinding I am I'm still experimenting around with different coolants and lubricants for surface grinding I tried Windex I tried soluble oil I tried way all I tried cutting oil and they all work almost the same I can't really make out much of a difference except for the mess they produce the the soluble oil of course gets everywhere on the machine and the machine is not built for wet grinding so not sure how I'm going to do that in future here I'm facing off the the ends of the bumper just to clean them up and concede it's blocked in with one two three blocks and held in place with a can't twist lamp okay checking clearance for hard milling the radius and you can see tell I just broke my car ride until by running it into the parallel with the spindle not running back with new carbide and no hard milling radius 50 HRC hardness 1000 rpm full depth of cut and little step over and this left me with very fine surface finish changing to a carbide chamfer yen mill cutting a nice 45 degree chamfer on top of the radius same here running at 1000 rpm and stepping over about point two millimeters per per pass going over to the workbench clamp it on the Wyss and also use an assortment of stones to clean up the radius I will start with a normal aluminum oxide stone and then finish it with a very fine Ruby stone those are used normally by tool die makers for polishing surfaces and they are the best stones you can get they last a lifetime a leave a very good surface finish they don't break down and they are horrible expensive so the base needs of course a two mounting holes for the bumper that's what you're going to do in the milling machine now setting up for drilling into the face using a three point three millimeter drill for the for a four millimeter tap toll using precision depth stop of course it's still working where dwell and second hole changing to a four millimeter for tap that's formula nominal diameter running at 95 RPM and slowly going down bit more and reverse it out of course you have to be careful when you do this you absolutely need to watch your depth otherwise you will end up with broken broken tap and I don't run it down all the way to a hard stop I stay away point five millimeters okay robot the bench and as you can see I took some black oxide finishing to this to these parts and I just I just buy the cheapest of these selenium dioxide bluing compounds on ebay which has dead fish in it and I tried various and they all work more or less the same bad I mix it i diluted with about 25% of purified water so I get a bit more out of it and it still works pretty good you can see even on these these tool steels i used for these parts i get a pretty good finish and it's not a deep black but it's it's an okay finish and it will over time get a nice wear on ya chest and look used in my collection of screws and thumb screws and stuff i found this nice big 6 millimeter shredded knurled screw which works very nice as they adjust the screw for the fun adjustment of the doll test indicator and what we're going to do is we're going to face off the end drill it out and pressed in a hardened steel ball so we have a hardened surface running on a hardened surface and that should give a very fine precise action for adjustment so let's go to the lathe and drill this out okay off-camera I drilled the end of the screw to 3.9 millimeters and pressed in the 4 millimeter ball bearing ball we put this together and you look through there you can see that the at the ball tip of the screw rests very nice on the hardened pad that we put into the indicator holder itself and now with the screw we have a with the two hardened surface is sliding on each other we have a very very precise and very fine adjustment for the indicator holder and as you can see I put some preload into the leaf spring I bent it over slightly just in device and hammered it over a few degrees so I have some preload already there and when we put this all together like this and trick for you and with the indicator in here now we have a very nice squareness carburetor we will flatten the base to and I will make some thumb screws here and here so it's good work okay I did a lot of fir golf camera because it's always the same I turned the two knurled screws and put it all together and a black and the base too as you can see it came then came out too bad looks okay not it's a bit it's not very even the black but it's a nice color for itself and it matches the other part and as you can see I can lock this with two fingers so that's a sign of a hint of precision the borer for the for the clamp is pretty precise the cross sector of material has the right dimension and D the threaded hole for the screw is in the right position so I get enough leverage by a minimum of torque for some proper holding force and the fine adjustment in front here works also very well the feedback from the screw is very nice with the hard ball running on the hardened surface of the way where pet in there you don't get any stickiness or stickiness is the term or raggedy movement or something like that it's just a nice action there so let's go to the surfaced lignin and I will show you how this thing works okay I brought the indicator up against my reference square and I searched for the high spot that's there and I seared out the dial and this is a mm of a millimeter per division indicator that's a about 110 thousandths of an inch so now we have our zero and I know that the square is square and we can take stuff out of the shop and check it for squareness for example we can take my good Japanese grinding wise and check if this side is square to this side let's draw it on the surface plate and bring the squareness cooperating contact and swivel it across to search the high spot and as you can see we read pretty much zero and that's what I expected from this slice we could also check my hands great to make us block this should be square to about five thousandth of a millimeter ah that's nice sound let's see yeah this is zero this is zero here we are - four thousand that means it's tipped away from the gauge yes I just plus four always keep in mind plus on this side it's plus two thousand here it's also plus four plus two sorry and here it's zero so this block is pretty good this is out of the beginnings of my scraping carrier so that's the squareness cooperator I've also a write up a double link down in the description where I have a lot of photos and some additional text and some fluff around this thing right now on my website link is down in the description so hope you enjoyed this build thank you for walking in to see you next time

Channel: Stefan Gotteswinter

Views: 60,849

Rating: 4.9543438 out of 5

Keywords: Squareness Comparator, squaremaster, flachschleifmaschine, härte, hardness

Id: 4F-bUiyFmWc

Length: 33min 15sec (1995 seconds)

Published: Sun Sep 18 2016