Belt Grinder 2x72" and 50x2000 mm

[toomast]

Sweet!

Sent from my LG-D605 using Tapatalk

[Boyan Silyavski]

OK, some more:

Welding the motor mount bracket that i cut from the original machine, as i savaged the motor from the junk yard. Clamped both pieces to the table first and then to a bar, then welded very carefully so not to distort the piece, as all wheels must be on one surface flat, otherwise belt will want to go left or right.

This is or ideally must be a very precise machine. First to be functional at all, then to be quiet and free of vibrations.







The belt grinder is meant to be used with using minimum 1.5kw 3 phase 4 pole motor and VFD. Now i had 3kw motor and in the same size and frame,plus Siemens 3kw VFD, so can you guess what happened :-)




Now as i dont have physical grinder to see in real life, judge or copy from, some things are not clear, so instead of finishing all 3 machines i will leave it here and start trying this one to see how it works.
For example:
-welding the bracket made so that the tooling arm could not pass through further from the end of the square cage, and according to my calcs there is no need to. The motor bracket and motor are there as i put them there for the reason of when 1.5kw motor its easy to flip machine to horizontal. It could be made more compact but then it must be much higher, so some decisions have to be made for future ones.



The paint. Probably industrial epoxy as its the best i could do here. The color is clear though as Jeff like that color, so i decided i would not insist on strange colors. It would be the aquamarine of Myfords and Bridgeport. Does any body know the exact color name or code?

Asking cause on all pictures they look to have different color/ poor white balance on camera/ . The second one seems right to me on my color calibrated monitor.

So any hint on the color?

[Noplace]

very nice, just curious how much would it cost to build one if you were willing to build in the future to sell it?

[Boyan Silyavski]

very nice, just curious how much would it cost to build one if you were willing to build in the future to sell it?

Difficult thing to say at this stage. But the KMG grinder sells for 1800$ and can not flip to horizontal. The best one sells for 3000$ and can flip and more . The ebay clones made from box section or/and 6mm laser cut pieces go for 800-1000. That without the wheels especially made for knife making.

On my prototypes all parts are milled/for now/ , so i have still to decide which ones are to be milled and which to be laser cut. Have in mind the price of the VFD and the 1.5kw 3 phase motor. Also welding things aligned precisely takes its time, so still not sure where to weld and where to bolt.

But the way i see it i want to have one model at ~1000euro /+30% if-when sold legally as a company / that beats all basic models around. But it may be high end 2000euro .

Cause its very simple. You want to make knifes, you need a grinder.You need a knife grinder. Thats it. FIY one way or another even if you totally DIY you will spend 500-800 euro on the complete machine. If you have lathe and mill and mig welder ~400euro at least.

By the way its a very useful machine even if you dont intend to make knifes.

So my idea is to make it accessible priced but not sure for now if it will be easily achieved. I started making changes on the drawing even while i am welding it together for this and that reason. So as i said this is a prototype to study whats working on the market and eventually make something better.

[JAZZCNC]

So as i said this is a prototype to study whats working on the market and eventually make something better.

Surprised you have made 3 identical when it's still in prototype. I Prototype lots of stuff and first version nearly always gets changed or improved in some way. Hell with my little router design I see ways to improve or make building easier just about every time I make one.

Surely would have made more sense to build one and test then improve second and test again etc.?

[Boyan Silyavski]

Surprised you have made 3 identical when it's still in prototype. I Prototype lots of stuff and first version nearly always gets changed or improved in some way. Hell with my little router design I see ways to improve or make building easier just about every time I make one.

Surely would have made more sense to build one and test then improve second and test again etc.?

I make one small wooden musical instrument as a side hobby and every now and then i have a whole day or 2 day, when i do sanding all day long. So the faster the better.

I needed a serious sander also for all the steel projects. I have a nice DIY 12" sander but what i am making here is a "grinder" not "sander" meanung it will have very serious surface speed with 120mm OD wheel at he motor spinning at 300rpm / 4 pole 3 phase 1420 rpm motor with VFD/

The other thing is that i have a knife project where i am at the stage of needing the grinder. I made the prototypes using small bench sander but as i am using one of the bad ass tool steels its very difficult to grind with belt sander to shape.

Plus as i found the typical paradox- " To make a grinder you need a grinder"


The design is more or less clear, a lot of DIY copies of the KMG grinder with plans in internet. The KMG is also a copy of an older machine, so i understood while looking at the plans that these are not just copies, but a concept proven through the years of abuse, that works. So i directly started building on it knowing that it will work.

Jeff needed a grinder, all of the above+ that they sell material in 6m, packets of 10, etc., so doing 3 machines at once made sense to me.


The next step from here is next week machine is ready, i continue my knife project and while having actual experience using it for knifes, i will meditate upon a much more brave design.


In fact Dean next step would be directly producing them by the 10, cause of the fixtures on the mill and the lathe is makes sense to make 10 pieces at once.

Needless to say that the experience from building CNCs till the moment helped in in such way that the only error till now was just 1 spot weld not at the right place.

[JAZZCNC]

Needless to say that the experience from building CNCs till the moment helped in in such way that the only error till now was just 1 spot weld not at the right place.

Erm I'd say the error was the spot welding.! . . . Doesn't look good or strong. Great for proto typing but not for real thing. It needs proper welds to give it credabilty as industrial strength tool.!