Homemade Surface Grinder Attachment - Want Flat Things?

so I hope clicking on that title got you guys excited because today we're gonna be making our own surface grinding attachment for a 2 by 72 belt sander so these have become very popular the design was originated I think by Travis where it's at TW 90 grinders his are pretty expensive though and I didn't want to lay out that kind of money so today we're gonna make our own there is a large thread at blade forums com of other guys out there making their own surface grinding attachments for their belt centers and I learned a ton by looking at their designs and looking at their bills so I learned a lot from there I'll put a link to that thread in the description below so you can go and read up on the pages and pages of users making their own surface grinding attachments special thanks to Stromberg knives because he not only had it awesome drawings of his surface grinding attachment but he also had great pictures and our email correspondence really helped out but I build so major thanks to him so today we're gonna be building one I'll go over first all of the items and pieces that I purchased and where I got them from I'll be putting a whole parts list and links and stuff below the Amazon links are affiliates but there are going to be a lot of links that are from other places because not all these items can be found on Amazon one of the major ones is Aliexpress now this is like a direct import company so when you order something on Aliexpress it's generally coming directly from China so you can expect ship times of like 20 plus days so it took a while to get some of these parts in you can get some of those same parts on Amazon but there are two or three times more expensive so I'll give you the options down below on how much your wait time is worth but the first thing we'll do is we'll go through all the parts and then we'll get on with the bill first of all we have the table here or the slide table this thing will be used to move our magnetic Chuck and assembly further or closer to the grinding wheel so you can see by turning that screw there you can move it back and forth in a very controlled manner the second item is the slider this has a set of five bearings roller bearings there and to guide rods in the long portion and they ride upon each other so you have a very nice tight controlled sliding mechanism here's a close-up of the bearings we are going to have to modify this plate so that we can attach it to the table the slider is about 600 millimeters long and about two and a quarter wide here is our contact wheel this is a serrated wheel to help with the heat it is about three inches wide and it's 200 millimeters or about eight inches in diameter the bearings on this contact wheel will be twelve point seven millimeters or 1/2 of an inch I selected the 12.7 millimeter option so that I can utilize a one half of an inch diameter bolt this bolt will be five inches long and I also bought an assortment of washers and a spacer as you see there so that I can space out the contact wheel from the tooling arm to around 1/2 an inch or at least a half an inch is what I use your machine may differ next up is the aluminum that we use for this build I ordered this from online metals calm these are 2 foot sections this first bar is 2 inches by 1/2 inch the next bar is 1/2 inches by 5/8 of an inch and then the last bar this will be our magnetic Chuck is two and a half inches wide by one inch thick last bar that we're going to look at here is going to be our tooling arm which is one half by one and a half inches square next up will be the hardware I spent about two hours at Ace Hardware making sure I had the right pieces so I didn't have to go back i over bought so this list here will be modified and I will show you that modified list at the end of the video I also had to modify the lengths of many of these pieces of hardware so I made sure that by long so I can grind them down I stuck with mostly quarter-twenty for this build however the only oddball size were these m6 fasteners up here in the top right these are going to be threaded into the table and the table does accept m6 this is a 7/16 of an inch in mill that I'll be using to mill out the slots in my magnetic Chuck if I was doing this again I would have purchased a two or three flute roughing mill then that would have made the process easier for aluminum that is these are the magnets there are sixty by ten by five millimeters about twenty of them off of Amazon and they are very strong so be careful when handling these magnets these are two handles that will be utilized on the surface grinding attachment I bought these off of Amazon as well and I bought them long so that I can shave them down to my required lengths so we're gonna go ahead and get started by cutting out these pieces of aluminum that large piece there is gonna be my magnetic Chuck we're gonna make that one 15 in 1/8 of an inch long and then the other two pieces the half-inch piece and the 5/8 piece will make 16 and so you can see that we're cutting them here on the bow or bandsaw and Swack stand this takes a little bit of time so just take your time feed it slowly and you'll get through it so after we get these pieces cut out we're gonna go over to the belt sander and just clean up the ends so that we don't cut ourselves on the birds while working with these pieces for the rest of the project so these bolts these quarter by twenty bolts will be utilized to attach this 5/8 piece to the magnetic Chuck so this will be the piece that holds the magnetic truck to the assembly with these three bolts so we're gonna go ahead and drill a quarter inch holes here three of them three quarter inch holes all the way through this piece and then we'll eventually tap the magnetic Chuck to accept those bolts on the flats of this piece we're gonna put some holes to accept those handles that I showed earlier one side will have a 3/8 hole since they're 3/8 by 16 and then the other side we're gonna go ahead and put a 7/16 hole so that we have a little bit of space in that hole for pivoting this arm so that makes sense in a little bit when this thing comes together but we'll eventually be able to pivot this magnetic truck so that we can taper tangs so what you see me doing here is passing these holes through to the half-inch piece because we'll eventually have to drill that half-inch piece to accept a 3/8 by 16 thread for the handles after we get the the holes marked through here we're gonna go ahead back to the mini mill and take that 5/8 piece and mill out a slot so that it can pivot on the 7/16 side you can see here that I'm marking these pieces top and right so T&R that's just so I can keep everything in line while I am working this project so we're taking a 7/16 in mill here and we're gonna mill out a slot to connect up with this hole like I said earlier at point of this is so that this piece will be able to pivot so just as a caveat I don't know when I'm doing when it comes to milling I learned a lot during this project as you'll see later on and so the early time milling you've seen this project don't judge me too hard on so this is what that piece looks like when we're finished up with it we have a slot on one side a hole on the other side the pivot on and then we have three holes going through the piece that will attach to the magnetic Chuck so these are where the holes are gonna go in and then this piece will will move as you can tell now with that slot so we're gonna go ahead and tap this bottom piece with 3/8 by 16 thread so we start off with a pilot hole and then we drill up to the size required for the tap I can't remember exactly what that size is but it is written on the tap and then using the drill press or using the mini mill we'll get that tap started by hand so that it's nice and straight in this bottom half-inch piece you'll see me doing that operation a lot during this project it's just a really good way to make sure that your threads are going straight through the piece however make sure you turn your mill off when you're doing that for safety so this is what that assembly looks like together you can see my handles are sticking out there we're gonna go ahead and cut those off so we get the ends of these handles cut off and then we go over to the belt sander and just clean them up a little bit so that they're nice and domed so now that we have that piece finished we'll go over to the magnetic Chuck and we'll mark through with a quarter inch drill bit where we need to drill the holes into the magnetic truck so in this project I'm lining up all three pieces on my right hand side and the Chuck will be centered on the table that we show later on in the video so after we get these nice holes marked we'll go ahead and drill a number seven hole to accept a quarter twenty tap now I show it in the second hole I'm actually only drilling down about three quarters of an inch into this piece because I didn't want to go all the way through so about 3/4 of an inch of thread on this magnetic Chuck later on when we are putting slots into this Chuck to accept the magnets mark off where these bolts are so just a test fit here it looks like it works great they all tighten up just fine and this is what this is similar look like before we mill the slots into the magnetic Chuck and then when you loosen up this one handle with the slot on the slot side you can see that you can move this assembly and pivot it to be able to do some taper tangs down the road all right so this is the slider or the yeah I guess the slider piece that we'll be attaching this whole assembly to I went ahead and drilled out the three mounting holes here to a quarter of an inch since they were slightly smaller and then notice that these cap head screws are a little too tall they said a little too proud to allow these bearings to freely slide so I chuck it up into my drill go over to the belt center and then flatten the tops of these a little bit so that that bearing assembly can slide freely in that slider as you can see here I'm not having any issues now that I've taken down the width of those bolts so we'll go ahead and get this thin place and we will mark through or lay out through with a drill bit onto this half inch piece and then we will drill out a number seven holes and tap them quarter twenty thread so this will attach that first assembly we just made to this to this slider and then these 3/8 by 16 handles we'll attach that 5/8 piece on to the 1/2 inch piece and then we'll attach a 1/2 inch piece to the slider with those three bolts that we just took down the tithe of the capsule 1 all right so here we are marking off where our bolts are on the magnetic Chuck before we do any milling I didn't want to mill over the place where we put those threads in there we're going to be utilizing these little magnets here note that they are very strong so be careful when you're using them so you don't pinch yourself they're about 0.38 and we're going to be using a 7/16 in mill to make the slot so that is plenty of room to get these little guys epoxy it in there hey guys if y'all are enjoying this video do me a solid and hit that subscribe button down below so I went ahead and started marking out the lines of where we'll be milling these slots they are about yeah 7/16 of an inch wide and then in between them I am making quarter inch slots or quarter inch ledges most of the way when I get towards the middle I have one or two on each side that will be 3/16 we're gonna be using 20 total magnets for this build so don't judge me too hard here I didn't know what I was doing and I didn't do an adequate amount of research online so I was running this mill about 2500 rpms and I was taking way too large of cuts here and you can tell what my results how ratty it looks so yeah don't don't do what I'm doing right here or you will probably tear up your equipment later on in the video I will show you the difference between this and a better depth of cut which ended up from me being around 40,000 and and way slower on my own my movement of a table so yeah you can see what happened here I blew a fuse and now whenever I put the fuse into my machine and turn on its shuts down the power for the garage so at this point the project we were in a little bit of trouble well the mill broke and I got about seven slots left to do I'm not quite sure how I'm gonna get this done I took the PC board out of the mill or at least a circuit board so I can send it off for repair I hope that fixes it it may not I may need to find someone local to help me out with these slots but we're gonna move on to a different part of the project voilá figure this part out alright so what you see me doing here is I'm mocking up this assembly so that I can make sure that my magnetic Chuck clears the apex of my wheel there that's just a quick check I want to do to make sure everything's lighting up so I'll be using metric bolts in connecting this bearing plate to the table this bearing plate is threaded in m6 threads so I want to make sure to drill those out so that my bolts can pass through even easily I think honor sink these holes to let the bolt head sit deep into this plate so that it will not contact the slider as you see here so we get them nice and deep so that we can slide this effortlessly so nano CAD came in on the clutch here drew out 50 mil by 50 mil hole spacing and it's the only way I figured that I can get this transferred to the other side of this plate I go ahead and put a piece of tape in the middle and then very carefully line up one set of holes with one side of this drawing and then the other set of holes I'll be able to drill on the backside of this plate this is the spacing required to attach this bearing plate to the slider table or to the black table there that you see there so you can see I have one side lined up there I'm going to go ahead and take a center punch and punch my other two holes in the backside of this bearing plate I'll then drill these two holes all the way through so that my m6 bolts can pass through effortlessly and then I will also Connor sink these holes so as the heads of the bolts does not contact the slider so now these four holes line up with the mounting holes of the table and I will go ahead and cut the m6 bolts to around three-quarters of an inch and then they will be able to attach the bearing plate to the sliding table note that by doing it this way I am slightly offset to one side however I still have an ample amount of clearance on my magnetic truck so this is not an issue all right so I got my board back in from mr. Pete brush I'll put his information on the screen here so that if you have any problems with mini lathes or mini mill PC boards you can send them up to him and he'll get them repaired I really hope this fixes my mill because the mill is crucial for this project mainly for the magnetic Chuck I have to mill the slots into the magnetic Chuck so that I can insert the magnets but also for the ledge that I'll be putting into the tooling arm so that my sliding table can have some relief into the tooling arm so I'll put it as information up here so if you have any problems with your Mills you can get them fixed to be honest I was pushing my mill too hard milling the slots my rpms were too high my feed rates were too high so lesson learned hopefully this fixes the problem so yeah major thanks to Pete his turnaround time was extremely fast I want to say it was almost within one week of me sending it I got it back so that's pretty awesome when you're messing around with these mills make sure you flag each one of these lines or these cables here so that the little the little markers don't get don't fall off and you don't lose your spot moment of truth here the mill turned on and we're in good shape again so we went ahead and got the mill reset up onto my workbench here just lined up with the holes I previously had and then we started more intelligently milling our slots here so I started using some some cutting fluid as well as only taking about forty thousand seven inch deep bites and moving about sixty four thousands a second on my table travel there so this is not working way better for me the mill was obviously in a happier condition as I was using it you can tell while you're milling if it's if it's happy or not so we got those holes Mannino slots milled there and then we went ahead with a hand file and cleaned up these corners just so that we don't cut ourselves when we're messing with this thing my older slots too definitely have a lot more roughness on the sides of the channel but I got as good as I can get with a file there and as good as I feel like I needed to and we're going to prep this thing up for doing our glue up so I went ahead and take this prep ball or you can use alcohol clean up these slots so that it will accept the two-part epoxy here so I started off by using some my remaining BSI epoxy and I moved on to j-flex for the rest of the slots down the road I ended up having a couple problems with the BS I've stuffed because it was taking me so long to get these little guys in there that some of it started setting a little too soon for me so I went ahead and replace those with G flex so when you're doing this make sure you're being very careful and holding down the magnet adjacent to the one you're inserting because they definitely want to be friends know and it's not fun trying to get them apart when they're all epoxy dumped together and slippery and whatnot so it happened to me a couple times while doing this but I found that if you hold down the previous magnet and then get a really good grip on the new one and get it into that slot immediately you won't be in good shape they pull up against each other but that's fine as long as they're still in the slots so also note that this takes longer than you think it will so I was in there for a while getting all these little guys in there but this is what it looks like after I had them all epoxy tin they're a little messy but it's just the nature of this job I went ahead and brought this magnetic truck inside into the nice climate-controlled environment so that it can dry quickly so I'm going to be milling the slot into my tooling arm to accept the table I'm going to go into it point four six inches into it and it's going to be four point five eight long and then the hole I'm putting in my tooling arm for the wheel will be about eight point eight inches into the tooling arm so the knock out most material I bandsaw cut this slot here and then I went back to the mill and took a half-inch in mill and just clean that up a little bit so yeah I'm taking about half a width of the mill cuts there and it's not it's not a very deep cut so it didn't take that long to get this nice and cleaned up so I want to note that I actually tried a different method of drilling the hole for my contact wheel and this tooling arm when I did not have access to my mill and I drilled the hole all the way through to one half of an inch so that I thought that I would be able to thread that bolt through that hole and just tighten it up really tight and I wouldn't have any issues however you can kind of see here that hole is not perfectly half of an inch and neither is the bolt so I had a lot of wobble on that side of my tooling arm so I found the better method is to go ahead and drill an undersized hole and then tap it to half-inch by thirteen threads and then screw in that axle into the tooling arm and it was way tighter of a fit but also note that I have about a half-inch I need to relieve this tooling arm because my threads on that actual bolt are not long enough so that's what I'm doing here i relieved it I went ahead put that half inch bolt in there I had a nice little spacer that I bought within a washer and then screwed this axle into the tooling arm get it nice and tight and then I can eventually put a nylock nut on the back end of that bolt so it's gonna be in there and it's it's never going to come out also there's no wobble in this wheel anymore with that type of assembly method do note that there are two operations in this method the tapping being the second one so you just need to really take your time and make sure you're getting a tap in there nice and straight so now we're going to move on to the table and attaching this table to the tooling arm I kind of eyed these they don't need to be super precise I just went ahead and I two holes here I'm drilling quarter inch holes and then I'll come back eventually and counterbore those holes so that the bolt heads will sit deep into these into this table I'll be using quarter-twenty bolts to attach this table into my tooling arm so I have four spots there I'm gonna go ahead and transfer these holes or this hole placement on to my tooling arm so I get it mocked up on there and clamped and I take a square and make sure it's square with the tooling arm and then I use a quarter inch drill bit to go ahead and start the divots for these four holes then I head back over to the mini mill with a number seven bit drill through all four of these with number Seven's and then tap them to quarter-twenty using the same technique that I've used throughout the video so that you get nice and straight holes now note my tap was not quite long enough to go all the way through this tooling arm so I ended up cutting down my bolts a little bit to think yeah around 1.2 inches so that they just stopped short of where my threads are this next piece here we're going to go ahead and put a stop nut or just a nut here so that the pivot arm will stop mechanically in the quote unquote zeroed position so we're going to go ahead and drill and tap this half-inch plate to quarter-twenty for that little stop nut the nice thing about the stop nut is you will also be able to use shims on this nut for specific tapering angles so as I mentioned earlier in the video I bought long and I overbought just to make sure I had the hardware I needed but you can see the adjustments I made in red to the sheet this is how my Hardware landed at the end of the project so take note here and then we're going to drill some holes in tap them on the edges of our sliding bar here these will be stops so that the entire simply doesn't come sliding off the bearings okay so here's the final assembly here I went ahead and used some blue off-brand Loctite to get everything nice and tight in this assembly you can see me putting in the the bolts to attack attach the slider arm to this half-inch plate I'll go ahead and I put in this top nut here it's not stop bolt and then you can see us putting in the pivot arm I did not lock tight these handles because I feel like they are gonna want to be moved frequently and now we're going to attach the bearing plate to the sliding table and then attach that whole assembly to the tooling arm so this is what that looks like when it's attached I use four bolts there to attach it to a tooling arm I guess you probably could use three if you wanted to but I just went ahead and used all four I also didn't use Loctite on this axle I figured it was tight enough with the with the back of my lock all right so I laid on a piece of wood since I'll be dealing with this magnetic Chuck this thing's kind of dangerous now that it's all together because it's just so strong of a magnet so I go ahead and I attached a magnetic Chuck to the entire simile with these three quarter-twenty bolts and this is what that looks like all right now we're gonna get the tooling arm put in to the belt sander I'm just throwing on a 2-inch ceramic belt here and then we're trying to slide this guy on there and then I noticed that something's hanging it up and then I find out that the culprit is the heads of these bolts here attaching the bearings to the table so we go ahead and with a die grinder just knock down those corners and now it goes on effortlessly so on these stop bolts I didn't like how the threads were impacting the bearings so I went ahead and took a chunk of horse stall mat here and drilled a number seven hole through the center of it and then we'll just we'll just thread that up on the end of our stops so that we have a nice rubber piece contacting our bearing our bearing plate so I also did this on the the bottom end as well so the first thing I did was I went ahead and I started taking a little bit of aluminum off the top of this Chuck and you can see that I am tracking the belt left and right as I go since my belt is smaller than the width of the Chuck this would be a case for getting a three-inch belt custom-made for this but right now I only have two inches so I feel like I got the Chuck nice and square and then did some test pieces here I took just a piece of steel and I started threading I noticed that threading it in just a little bit at a time really helps but you can see here that you can kind of get a workout doing this too and then these are the results I had with my little test piece so I'm looking forward to using this thing in the future and really good in delve in so as far as this build goes mechanically it is completed note that there will be some learning curves involved with using this surface grinding attachment and most notably probably your feed rates on this table you want to feed in probably around one to five thousand at a run if you go any more than that you'll probably get some dishing or warping or even like a bad finish so feed in just a little bit at a time and then probably move this back and forth until you are no longer seeing sparks when it comes to measuring your results you saw that I use a pair of digital calipers these probably are not accurate enough to really give you an idea of how you're doing I've ordered a cheap set of micro meters so that I can get a better idea of this machines performance my target with this machine is about a thousandth of an inch over the my entire workpiece so I feel like that's pretty good for fixed blade knives I'm thinking for folders you may need a little bit higher level of precision but you're probably not gonna get that with with this other than that I probably order some 3-inch belts I think Phenix abrasives will make custom belts I'm not sure about that but I want to get some 3-inch belts here so that I can have an option for wider work pieces and then I think I'll go back and refinish or re true up my my magnetic shop with a three inch belt just to just to make sure that's perfectly true also if you're going to be flattening anything that has a warp in it you may need to put some shims under that warp so that the magnets won't pull up warp out while you're making it flat and then when you take it off you still have the warp there so there are going to be some learning curves like that with this machine that you may need to work on you will see me working through that in the next couple videos that I use this machine all my knives going forward so all the knife pills I'll be putting out in the future I'm going to be working through those kinks with this machine so if you want to see that go ahead and hit that subscribe button down below and go ahead and follow along and with that I hope you all really enjoy this video if you did hit the like button and I'll catch all y'all on the flip side [Music] you [Music]

Channel: Red Beard Ops

Views: 441,709

Rating: 4.819159 out of 5

Keywords: red beard ops, jkeetonknives, knifemaker, knifemaking, homemade surface grinder, surface grinder attachment, surface grinder, SGA, DIY Surface Grinder, DIY Surface Grinder Attachement, Wuertz Machine Works, Wuertz grinder, OBM Surface Grinder, Origin Surface Grinder, Wuertz Surface Grinder, Reeder Surface Grinder, Surface Grinding, Surface Grinding machine, custom surface grinder, Home Built Surface Grinder, 2x72 belt grinder, 2x72 belt sander, 2x72 SGA, surface grinder diy

Id: _Q2aujE3pWk

Length: 34min 4sec (2044 seconds)

Published: Sat Feb 08 2020

Reddit Comments

[u/monkeywelder]

Corin will praise Krom for you.

[u/LedToWater]

Eleven ten-thousandths of an inch sure sounds good to me. A little too good.