DIY surface belt grinder

[Natlek]

It s time to say again.....this is the last grinder i will make
I have six of this linear bearing set , about 18 inch long .And two set long about 60 inch. I got them a long time ago, I wanted to make a CNC grinder.....no way ! They are very expensive and best quality .Now it s time to make use of them ...........surface grinder ! I have tons of quality ball bearing , i have gas forge I even have small anvil and hammers of course ........ But after I straighten ball bearing race they need to be surface ground ....so here we are
Plan is this ...........I will make/use belt grinder / 2x42 belt /for feeding , one set of this linear set is more then enough for sliding part .What I m not sure if I need to do is ..........do you think that If i grind part by part / will be better-faster / I mean grinding like real surface grinder ? Or should I make it fixed ? Which make building much simple and grind whole steel at once ?
I will use 2HP 2800 RPM motor with 7-8 inch wheels, rubber and hard surface .
What do you think ? I kind of cheer for the first solution...to make use of that lathe part I don t need anymore jig for hollow grind
One more question......home made plate with magnets or real one ?

 

[A.McPherson]

Real magnet plate with on/off mechanical switch from china. Not electro mag, just mechanical.

 

[JDWARE]

Looking forward to this Natlek. I think this is where the Surface Grinder Attachment was always heading .... a dedicated grinder, solid, precise - sized for knifemakers' needs. I'm in a part of the world where there are very few used, full size, Surface Grinders available. The ones that are, are expensive and worn-out.

I'd go for a permanent magnetic chuck as well. I have seen a few nice electromagnetic chuck builds though, using magnets from microwave ovens. A lot of work to do well. Either would be better than the milled out aluminum and epoxied magnets.
Good luck
Saludos
J

 

[Natlek]

Well , in scrap yard I found this for 10$ .They are 32 x 3.5 x 1/2 inch , machined surface from both side, they will make my job easier . I took them from some kind of printing machine ... never seen something like that , maybe more then 5 tons weight.
I ordered this, I hope I wasn't wrong .........https://www.amazon.com/VEVOR-Magnet...CEM20C5SGFC&psc=1&refRID=WGWET6X3ACEM20C5SGFC

One part of the construction solved , drilling and taping hole is easy part. I have not decided whether to use one rail or two.
Now I can think now to make belt grinder and frame .....

Well , I don t like what I see on this last picture .It will be sin to use this linear bearing for one inch movement , don t you think ? I can find better use of them........like for some grinding jigs. I will make it lathe type ................

 

[Natlek]

Some progress ..........tracking , tension solved .I need drive wheel and grinder part is done .Sliding part done , i need magnet chuck to finish
it .

 

[reevestx]

pretty clever

 

[3fifty7]

Nice shims on the contact wheel !

 

[Pinoy Knife]

im sorry but i have to ask !!
why not machine Dovetails into the metal ?? with a nicely done dovetail the parts move very precisely..
you could also cut a T slot /or a number of them and use bearings to make it smooth travel..
then mount your magnet to hold the blade/motor/wheel and be done ..
i think by making my own slots/dovetails i can make it also precisely raise/fall to adjust for different thickness metals..

Again i'm sorry but just have to ask !!

 

[Pinoy Knife]

HFS(R) Multifunction Worktable Milling Working Cross Table Milling Machine Compound Drilling Slide Table for Bench Drill Adjustme X-Y.. (Found on Amazon )

at least use something like this. then you just have to worry about up/down adjustment..

 

[Natlek]

im sorry but i have to ask !!
why not machine Dovetails into the metal ?? with a nicely done dovetail the parts move very precisely..
you could also cut a T slot /or a number of them and use bearings to make it smooth travel..
then mount your magnet to hold the blade/motor/wheel and be done ..
i think by making my own slots/dovetails i can make it also precisely raise/fall to adjust for different thickness metals..

Again i'm sorry but just have to ask !!

Can you make some draw of how you would make this surface grinder? I really don't understand what do you mean ?

HFS(R) Multifunction Worktable Milling Working Cross Table Milling Machine Compound Drilling Slide Table for Bench Drill Adjustme X-Y.. (Found on Amazon )

at least use something like this. then you just have to worry about up/down adjustment..

You mean on something like this ?
https://www.amazon.ca/MultifunctionWorktable-Milling-Compound-Drilling-Adjustment/dp/B01NBU6B72
If that is that , it is to weak to carry weight .....only magnetic chuck weight 20 kg ...

 

[Pinoy Knife]

Natlek
id love to draw it out but don't know how to on a computer...
take 2 bars of metal, measure 2 slots at equal width to each other and make 2 slots with a straight cutter about 30-40% of its thickness then Dovetail "Female"
now do the same on the second piece except this time you cut the matching "Male" dovetails out..
once the machining is done the parts should slide together like a tight puzzle.. 20 kg is about 50 lbs for the magnetic chuck
as long as the "Dovetails are clean and tightly cut to each other it should easily hold the weight..

you could also do the same with a t slot cutter. you just need each part to be "Male" "Female"
this is how all precision parts are made .. look at a milling machine .. everything is dovetail cut and uses "Gibs" to set the moving tension required.

again good idea but if i think i know a better way to build this ,and not share it with you, i would not feel very good about that .
i would much rather share and let YOU decide which way you want to build YOUR machine..

 

[Natlek]

Natlek
id love to draw it out but don't know how to on a computer...
take 2 bars of metal, measure 2 slots at equal width to each other and make 2 slots with a straight cutter about 30-40% of its thickness then Dovetail "Female"
now do the same on the second piece except this time you cut the matching "Male" dovetails out..
once the machining is done the parts should slide together like a tight puzzle.. 20 kg is about 50 lbs for the magnetic chuck
as long as the "Dovetails are clean and tightly cut to each other it should easily hold the weight..

you could also do the same with a t slot cutter. you just need each part to be "Male" "Female"
this is how all precision parts are made .. look at a milling machine .. everything is dovetail cut and uses "Gibs" to set the moving tension required.

again good idea but if i think i know a better way to build this ,and not share it with you, i would not feel very good about that .
i would much rather share and let YOU decide which way you want to build YOUR machine..

I'm sorry, but I still don't understand what you're suggesting ? Why I need to build dovetail ? I know how to make it but for what i will need it ? To replace linear bearings which I will use for magnet chuck or for what ?

 

[Pinoy Knife]

yes to replace the bearings with

 

[Natlek]

I make some changes in design , this is how feeding will work ...............

While I wait for magnetic chuck to arrive i make other one , just for grinding distal taper .I will use 10x10 mm magnets .It would be hard to make big one / 20 kg / to do that...........

Aluminium plates are 10 mm thick so I used thin G10 and thin micarta so magnets can sink little in holes...........
Now I need to taper lot of holes for tapered head bolts..........I hate that part of job

 

[Natlek]

Nice shims on the contact wheel !

Well , no more shims ..............but again i use temporary contact/drive wheel which I took of from my horizontal grinder so I can continue with work on this project .
I can't believe they lost my new one contact wheel in shop of my friend....I didn't take it when it was done, now we can't find it where it is
I make some progress......as always I change design depending on what I find and I can use in this build .......... almost finished .Now it look like something that might work .Grinder part works , tracking is perfect ........

I made everything so that it could be adjusted , but for now it seems that it will not be necessary..............look perfect

Shaft is 20mm hardened steel with hard chrome surface , bronze bushing inside ...... solid as rock !

I need to drill several holes and then to install this part and then magnets..........and to find that wheel !!

 

[Natlek]

Almost done . I install feeding screw and it works perfect . I need to make some adjustable kind of screw for dial indicator so i can zeroing ? before grinding.Today i will glue magnets and maybe i will trial run with this wheel .........32 m/s
I wonder what if i install some kind of spring on moving part? I think that it can help with more steady moving while I grind ?

red is spring ?

 

[Natlek]

Well , finally i grind something with this THING I still can t find my new cast wheel in shop of my friend so I temporarily borrowed this AL one from other grinder .It has radius for better tracking so i needed to remove that radius ...Piece of sand paper on chuck solve that fast .Then I grind chuck and I discovered new problems to solve......when I designed this i was counting on two inches max. width of steel to be surface ground .I forgot I needed to surface grind chuck first . So I need to cut little from back side of chuck and to move little that part which hold feeding screw,so I can grind the whole chuck .Fortunately that part is not fully welded yet, just four spots .I hate aluminum dust more than from wood, the whole shop now shines with aluminum dust
But , I like how this thing work ...........I think i make something here ...........something
good .32 m/s and side feeding are spot on ! Almost done ...now my search for magnets start .........I lost them too ..................in my scrapyard shop

 

[Natlek]

The easiest way to clean the belt from aluminium is to start the grinder backwards / or to flip the belt / and use steel brush. Gone in 30 seconds ................clean belt !

Now about this MF grinder !! I cut both side of aluminium plates so i get that clearance ! BUT now I can t grind that corner........................another building mistake ! I will leave it as it is for now, it doesn't matter when grinding steel . I have several way to fix it but not now .
When you don’t have magnets.......double tape works , just watch temperature .The tape withstood the test, I sanded two blanks .........My caliper say that everything is super ...I will check with micrometer tomorrow , now is to late even for me.
I make short video .......I think i will like this new toy !
That's it.............. I don't think I have much more to say in this topic

52100 , this thing grind steel fast ........

I cover double tape........ I can feel that i will need it I don t think i will find magnets soon ....... and I pay almost 60 Euro for them !!

One more question , I forget about that ..................half a millimeter below the aluminum plate is enough for magnets ? In case i found them

 

[fitzo]

Can you find the magnets in the US online? My post office is close.

 

[Natlek]

Can you find the magnets in the US online? My post office is close.

Thank you my friend , I really appreciate that I will find them ... I think I'm looking for them in the wrong place............I think that they are somewhere in the office at my service not here in shop . I bought them from Germany but they arrived at the address in Austria to my brother. ... Then one friend who came from Vienna brought them to me , I think that was in service ... I'll ask him just in case.Soon my real magnet chuck will come from USA.
Thank you again
I grind something this evening , I grind about half mm. from both side .It is hardened steel cut from really big circular saw for granite ,27 cm. long and 8mm. thick .Micrometer say 0.01mm. difference and that only in one corner....and I think i know why was that .... it is from steel not from grinder .
Also I allowed on purpose grinding steel to fly of chuck while i grind on it , nothing special , can t make any damage or it is dangerous .BUT I install stopper /2mm/ so i can make heavy passes if I ever need that , without worries if chuck will hold steel or not ..And again i forget to try 100 grit ceramic ...this is 40 grit Zirconia belt and i like that finish ,high belt speed is good thing !

Edit .....one more thing , watch on temperature on your chuck ........Mine get quite hot while I grind this steel , hot enough to burn hand easy .My magnets have just 80 Celsius working temperature ......................