How to work? Drying here, drying there. I don’t know! Here it is, our shop upgrade again. Bought this pedestal grinder Mighty. Idk what type is it the tag is completely rotted Well there are motor and spindle and belt drive It’s heavy maybe 300-400 kg The lamp 36 volts is still here The wheels are probably 300-350 mm Massive tool rests with such a T-slot Just buttons, so there is a starter there is a common emery wheel and here is a fine-grained wheel cheeped off We have this small grinder A drill bit like this how to sharpen? You cannot do it well. 40 mm OD But here please Whole cutting edge fit So… or maybe to snag smth. so such a machine will be useful As well needs to be restored, cleaned This cover is of plate not cast iron housing i.e. to setup small grinder on top like usually it’s need to strengthen somehow remake. So… another patient for recovery It was concreted into floor Until here All was poured. Were hollowing out with jackhammer Even eyeshields we got Is this original?
Yes, what? You’re gonna hang drawings here To the sparks don’t hit the eye, put the glasses on, shitguy! (joke) Also grabbed this drill press It’s a usual 106-th drill 2N106 or smth. Small chuck is there I believe it’s in work condition Judging by plug, 3-phase Flat belt as usual, machine considered as high-speed How much? Up to 8000 rpm? 8 speeds From 1000 up to 8000 rpm Start, stop, light There is no lamp Abracadabra… Moscow hi-speed precision machines plant As well wether for restoring or… to sell straight away. OK guys, I continue to design T&C grinder In order to increase overall rigidity or only the base rigidity I decided to add ribs, besides it will increase the space for placement mounting screws and it just will be easier to grab machine for carrying. Such bars I chose just because I had them Long ground bars just need to cut and T-slots can be used for clamping to fix the table on the one side and another The rotary table will be moved between guide ways to change sharpening radius On this stage the interesting question arises What the scraper sharpening radius should be? Or in what the range is to be adjusted? Soviet benchwork textbook recommends radii 30-50 mm It seems too little Cuz I always believed I sharpen my scraper blades with radius 300-400 mm And in the comments to the last 2 videos they recommended as well 300, 400, 500 mm So I was confused I grabbed my blades new, old factory made… Now let’s measure up the radii of the blades sharpening Blade #1 I’ve clamped in the tool maker vise on the mill set indicator point on the cutting edge Now I’m gonna traverse the table and measure the cutting edge convexity Here it is top point 16 hundredths 0.16 mm Of cause the blade must be leveled before, to indicator reads 0 So it was blade #1 that I used just recently This is #2 it’s old, almost ended We have 34 hundredths 0.34 mm This one I purchased recently is factory made double sharpening, 2 edges, VK6OM It’s brand new, I haven’t used it yet Measuring convexity and getting 19 hundredths, almost 2 tenths This is my very first blade made of HSS from mill cutter it’s sharpened for scraping dovetails See the corners are cut-off and we got here 25 hundredths Perhaps there is a formula for radius calculation by chord length and height of arc but why strain the brains when we have CAD drawing the arc by 3 points and then stupidly measuring radius There are our 4 blades, first had radius about 100 mm 2-nd was 50 mm factory blade has the largest radius almost 150 mm HSS blade has about 100 mm as well Thus, we took 4 blades The range of sharpening radius Min. is 50 mm, max. 150 mm As you can see, it’s not 300, nor 400 nor 500 mm So in our machine design we’ll be focus on that range from 50 to 150 mm Just about the same numbers is on this gauge from a famous firm And if I’m not mistaken it is a replica of grinding gauge of little-known firm BIAX To secure scrapers with round shaft such a set prism (V-block) is needed, we’ll make it But the grinder must allow to fasten a flat scraper I draw it simply this rod is a scraper Overhang of the scraper end from the center of rotation of the table will give us the blade radius And from above it is secured by special clamp not shown here. Now let’s continue making parts of… How do people cut rails? They cut with machines.
No. Yeas, it’s what I said Let’s go ahead playing toy blocks. Checking main layout Generally, DIY machines are different by some “squareness” because of use what you could find Not everyone has ability to cast large housing parts So for working layout it’s good to use these USP, universal fit-up jig, such blocks They was producing by our industry in great amount and assortment Someone build machines entirely from USP The disadvantage of USP is that it’s hard to be machined cuz they heat treated. But they have accurate geometrical sizes ground planes, reference surfaces, slots and mounting holes including threaded. Like such the scraper is setting up on the prism The overhang is adjusted that gives sharpening radius The radius not hard to guess is from table rotation center to wheel face So far it’ll be clamped by this USP A-clamp In perspective it could be replaced by a special clamp, for instance eccentric. And by such circular motions right by the scraper handle the blade’s being ground From the beginning the idea was that the blade is to be sharpened in scraper Not to take it out from there So far the machine has no any feed apart from this circular, rotary feed Gonna try like such for now and later will see if there is a need for feed Basically, the grinder is not only for scrapers but for any other tool You can grind any scraPPers like this DIY scraper for paint or smth. And for sharpening small radii you need to get the table closer to the wheel. That’s why table traverse is needed. For a flat scraper with flat bar holder would be better to make special adapter instead of this V-block. It’s suitable in height but you should increase force of clamp tightening there is some uncertainty in setup some shoulder is needed on this side The table and the base is to be clamped There will be some clamps And using accurate ground blocks USP as distant pieces is wastefully I could cast an aluminum spacer Because I haven’t got a ready to go aluminum brick size needed For now I’ll put these steel bars Heavy is good, heavy is reliable I have it previously cleaned up, roughed Needs to mill to size And like such you can get table closer to the wheel so you can sharpen even small tools like this little scraper but there is too big V-block, needs to be shortened I.e. for different tools you need to have different adapters. Well, it’s going like such. Iron is heavy, my machines small, machining take time. So I’ll be wrapped on it and continue in the next series. Thanks for watching Please subscribe, if you haven’t already. Feel free to comment, I’ll answer for sure. Until next time! See ya.