Chinese belt grinder for cheap?

[jeness]

Hello everyone!
These are available since some time now, but there aren't really a lof of opinions on it available. Does someone have a unit like this, or know someone who owns one? I found two australian gentlemen who bought it, and both were really pleased with it, and two 5 star ratings on ali. What surprises me that the only opinions I found were positive, and no negatives till now. They use big sealed Japanese made NSK bearings, the sheet metal looks like 1/2" or thicker, has a gas spring, seems well built and thought out, etc. So it doesn't look like typical Chinese junk.

I am talking about this one, lots of sellers have them though:

https://www.aliexpress.com/item/-/32845409414.html?spm=a2g0s.8937460.0.0.74bd2e0efHb14J

For about 950$ delivered I would get a unit with 2hp motor, VFD, 12" contact wheel, platen attachment, and small wheel attachment with two small (1", 1.6") wheels. Locally I can't even get the materials to make one similar for this price, not to speak about time involved and labour costs.

So if someone has some kind of info on these, than please don't hold back!

PS: I know, buying anything Chinese can be hit or miss, that's why I am asking if someone has more info than myself. For the price, this unit is even than really nice if it needs some tuning before use

 

[Jesse WW]

Oh boy where to begin.

I bought one of these just over a year ago, and was in the exact same boat. I was VERY skeptical, but for some reason I just went ahead and purchased it anyway, praying that it wouldn't be total junk. Talk about buyers remorse.

Is it junk? Yes... and no.

The bad:

The first major problem was the motor. Because I bought the variable speed version, it came included with a VFD. For some reason however, it came with a single-phase motor (which obviously it shouldn't have). I contacted them regarding this and believe it or not, they said their single-phase motors worked with the VFD... Okay. No it wont... But okay.
The motor DID work... sort of. The sound coming from it however wasn't good. After what was probably 4 hours of grinding, one of the two big motor capacitors blew a big puff of smoke and ceased to run (which I was expecting to happen sooner or later). Damn did it stink. I contacted the seller, they asked a few questions, and I haven't heard from them since.

Instead of returning it I decided to bite the bullet and pay an additional $250 for a high-quality 3-phase motor. I had some difficulty mounting the new motor however because the mounting holes on the grinder were slightly narrower. This was easily fixed by making an adapter with some scrap RHS tube I had laying around.

The platen and platen mounting brackets were total junk (they didn't even line up with the belt). So I made a new platen and platen mounting brackets.

The tool rest and tool rest mount were also absolute junk. So... I made some new ones.

It is designed for 82" belts, 72" belt WILL NOT fit. To get around this I drilled and tapped a new mounting hole just above the original one for the gas strut in order to decrease the tracking wheel height. It worked... but only just.

The good:

The frame is solid... poorly built and a little crooked here and there, but very solid nonetheless.

The quality of the attachments like the big wheel arm, small wheel arm, and flat platen mount/arm (not including the actual platen and mounting brackets or tool mount) are fairly solid and work well. All the wheels are very good IMO.

I have no idea if the VFD is of good quality or not. It works however and is still going well.

Would I recommend this? Absolutely NOT. I was able to make the best of a crappy product by spending the time to improve upon what was wrong with it. If i could travel back in time, I would spent the extra $$$ to buy a better quality grinder. The time and money that was put into making this one functional... I might as well have spent the extra dough anyway.

Sit tight and i will get some pics to post.

 

[Ken H>]

I see in the link above they show

2HP variable speed drive KBAC 24d .Speed Control from 0 - 2800 rpm

If you really did get an actual KBAC-24D VFD it would be nice, but they show photos of a standard Chinese open frame VFD
With the price down in $700 to $800 shipped range, those sure would be tempting - especially with all the accessories included, even down to small wheels. Since they're designed for the knifemaking world (with USA in mind) why in the world would they use 82" belts rather than 72" belts?

 

[One Armed]

$950 shipped? Not worth it! As Ken said, if it was around $700 it would be tempting. But at that price, there are a few high quality setups you can get minus motor/vfd. Add those & you're still around the $950 price.

In addition, you say you can't build one locally for that price? Where are you exactly? I'm in Philadelphia, Pa., and ordered everything online to build my own. And I didn't use square tubing. I ordered 1018 cold roll bar stock & billet aluminum for the frame/toolarm/platen, etc. I spent less than $600! The only thing I don't have is the small wheel attachment.

 

[Drew Riley]

Since they're designed for the knifemaking world (with USA in mind) why in the world would they use 82" belts rather than 72" belts?

Probably a case of “bigger must be better!”

That, or a translation error.

 

[One Armed]

Probably a case of “bigger must be better!”

That, or a translation error.

Technically speaking, that is true with grinding/sanding belts. Whole reason I first adapted my 2x48 grinder to use 2x72. And I designed the grinder I just built to accept 2x90 belts! But absolutely, the grinder MUST accept 2x72! This is wothout contestation!

 

[jeness]

$950 shipped? Not worth it! As Ken said, if it was around $700 it would be tempting. But at that price, there are a few high quality setups you can get minus motor/vfd. Add those & you're still around the $950 price.

In addition, you say you can't build one locally for that price? Where are you exactly? I'm in Philadelphia, Pa., and ordered everything online to build my own. And I didn't use square tubing. I ordered 1018 cold roll bar stock & billet aluminum for the frame/toolarm/platen, etc. I spent less than $600! The only thing I don't have is the small wheel attachment.

Here in Europe we aren't as fortunate sadly Shipping from the US is around 300-500$ depending on what you buy. The only commercially available alternative here would be a HAIM grinder, but that one would be around 2000-2500$ with the same attachments.

 

[jeness]

I see in the link above they show

If you really did get an actual KBAC-24D VFD it would be nice, but they show photos of a standard Chinese open frame VFD
With the price down in $700 to $800 shipped range, those sure would be tempting - especially with all the accessories included, even down to small wheels. Since they're designed for the knifemaking world (with USA in mind) why in the world would they use 82" belts rather than 72" belts?

Good question, looks like in Asia and Europe the standard size is around 2000-2100mm length, thats 79-82".

 

[Stromberg Knives]

Here in Europe we aren't as fortunate sadly Shipping from the US is around 300-500$ depending on what you buy. The only commercially available alternative here would be a HAIM grinder, but that one would be around 2000-2500$ with the same attachments.

Well, I wouldn't say you're without cost effective options here in Europe.

Here are a couple of choices for you to look into.

1. For about £1000 you'll get a nice grinder (with IP66 VFD and 2 hp motor) from Nick in Greece. I have two of them and I'm very happy. He can also help you with all accessories you'd need.

https://www.ebay.co.uk/sch/konstantinos_95/m.html?_nkw=&_armrs=1&_ipg=&_from=

2. You've also got this guy in Croatia, I've bought wheels from him, no problem at all.

http://batkovic-alati.hr/

His prices are very competitive.

3. This is also an alternative, I've heard good things about this guy in Bulgaria.

http://volf48grinders.com/

 

[Jesse WW]

Probably a case of “bigger must be better!”

That, or a translation error.

Nope. Not a translation error. When I got the thing and tried fitting a belt for the first time, 72" belts were way too small.

Its very strange, because I cant even find belts in 82x2, and if I google "82x2 grinding belts" it just brings up the results of this exact grinder. Very odd.

What would be funny is if it was a translation error in the build plans prior to manufacturing, instead of in the product listing.

 

[mike-E]

jesse WW, did the grinder come with what appears to be a 10" drive wheel? It also looks to be a 5 or 6" idler.

 

[skillgannon]

7 is right next to 8 on my keyboard

 

[Drew Riley]

Nope. Not a translation error. When I got the thing and tried fitting a belt for the first time, 72" belts were way too small.

Its very strange, because I cant even find belts in 82x2, and if I google "82x2 grinding belts" it just brings up the results of this exact grinder. Very odd.
What would be funny is if it was a translation error in the build plans prior to manufacturing, instead of in the product listing.

By translation error, I meant some machinist in China probably asked "what's a good size belt for a grinder", and mistranslated 72 as 82 when he was designing it.

 

[Jesse WW]

jesse WW, did the grinder come with what appears to be a 10" drive wheel? It also looks to be a 5 or 6" idler.

The idler is about 5". The drive wheel I don't know the exact size of but I can post back when I get the chance. I would say it is about in the 10" range.

 

[mike-E]

Thank you for taking the time. Also, how is the vibration? A drive wheel that big with just a slight bit of wonky torque from the set screw can cause issues.

 

[Jesse WW]

No problem friend. Here are some images of my setup if you are still interested:

Here is the main setup (with the new motor).

As I said the platen and the platen mounting brackets have been remade. I had a buddy laser cut and bend them to a perfect right angle so they fit perfectly.

Here is the big wheel attachment with the remade rest and mount bracket.

Small wheel attachments. Both small wheels should have a rubber sleeve, however one come loose and I removed it.

All three attachments.

This is where I had to remount the gas strut in order to fit 72" belts. Note the hole underneath to the left where it was previously mounted. Its a temporary fix currently. I'm thinking I might eventually throw a compression spring in there to replace the strut.

The mounting adapters for the new motor. The holes were about 1" wider apart if I recall. Centering of the drive wheel was atrocious so the adapter helped me get everything centered.

This is the VFD it comes packaged with.

The big wheel is 11.5"

The drive wheel is 8.5"

The idler is 5"

 

[Jesse WW]

Thank you for taking the time. Also, how is the vibration? A drive wheel that big with just a slight bit of wonky torque from the set screw can cause issues.

The big wheel can be balanced a little better, but for me the vibration is tolerable. It also depends on the speed/frequency setting on the VFD.

 

[mike-E]

Awesome, thanks again. Looking at the idler wheel tracking mount. Would it be possible to pull the hinge bolt out and flip the whole wheel/ bracket upside down? To where the idler wheel sits lower and gives you extra belt slack? Or would the nut on the back not clear the inside of the arm?
Seems really strange for the idler upright to be welded so far forward on the tool arm pocket. Almost like they did everything they could to make 72" belts unusable.

 

[Jesse WW]

Awesome, thanks again. Looking at the idler wheel tracking mount. Would it be possible to pull the hinge bolt out and flip the whole wheel/ bracket upside down? To where the idler wheel sits lower and gives you extra belt slack? Or would the nut on the back not clear the inside of the arm?
Seems really strange for the idler upright to be welded so far forward on the tool arm pocket. Almost like they did everything they could to make 72" belts unusable.

I did try what you described. The nut that fastens the idler wheel to the bracket does get in the way of the bolt used to adjust the idler angle.

I also forgot to mention - the 72" belts still did not fit when I remounted the gas strut a little higher on the idler arm. The adapters I made to mount the new motor allowed me to move the drive wheel inwards a little more, which is what did the trick. Still a tight fit though.

This thing is just filled with too many inconveniences.

 

[Ken H>]

Jesse, it sounds like you did so much work you could almost have built from scratch. I'm glad you've got it working good. That VFD, is it sealed? OR - are there air ventilation vents on the side?