Belt grinder

[Bert51]

Wow, I thought she may have seen the account balance after buying the new toy

Sadly I am unable to give blood or donate my organs, I wish I could but I hope other people do.

I'm pleased she is okay, that's the main thing.

You can start on it again tomorrow.

Bert.

[dikman]

Actually, she saw it on the credit card account and said perhaps I should have it as a combined birthday/christmas present.

Here's the "finished" product, a cheap (because I used whatever I had in the sheds) and rough-as-guts (well, I did give the wood a rough sand to remove most of the splinters) dust catcher! I routed a slot in the rear piece so it can be adjusted for height, a few assorted plumbing fittings, a spare hose from an old vacuum cleaner and a cheap shop vac. Works well for leather and wood (no good for metal, of course), but even with the vac outside it's still noisy!!!

Now I think I need to buy one of those digital tachometers off ebay so I can measure the speed and mark my adjustment dial.

 

Edited June 6, 2020 by dikman

[Bert51]

Looking at the video of the grinder being used, I think that will do what you need it to do, not much will get missed.

Bert.

[RockyAussie]

Now that is looking promising - well done. I should also ask you to thank your wife for giving as she has done and I hope that she does not ever get such a bad result again. I wish her well.

On 6/5/2020 at 11:12 AM, Spyros said:

Shipping from China is pretty terrible these days because of COVID, if you want I can send you mine for a while, let me know.  You don't need it all the time, only to take readings when you change something to make sure dust levels haven't change much. 

@Spyros I would like to take you up on your offer as I have been asked to do a little consulting and training on the croc belt making by the end of this month. Getting one out a China that quick is unlikely at present. I would be happy to buy yours for $100 for now if you would like to go that way please pm me you details. They have a sanding machine set up for this but from what I have seen I know they need a lot better and I am thinking about making them up something way more heavy duty and as they are a BIG company the dust extraction will be an important thing to be clued up on. I will appreciate it a lot if you can help me with this one.

Brian

[RockyAussie]

On 6/2/2020 at 5:37 PM, dikman said:

I have a belt grinder which I use a lot - metal, wood, plastic, nylon and yes, leather. The problem is it's too fast and burns the leather and wood if I'm not very careful. So I bit the boolit, so to speak, and treated myself to a new grinder, something I've wanted for years. This one is designed primarily for knifemakers and runs 48" belts, and I went the whole hog and bought a 3-phase motor with it and a separate VFD. It took a while to figure out how to programme the VFD but now I can run the grinder from almost nothing to flat out! No more burning leather.

I'm so impressed with the VFD/3-phase motor setup that I'm thinking of fitting one to my lathe.

@dikman Can I ask what hp that motor has? I am also thinking of running a similar arrangement and could use a little help on what and where I may be able to get a hold of some of it along with any kind tips you may have to offer. I do like how you have the control knob box separated and keeping the main VFD nicely away from the messy stuff - also well done.

[dikman]

Brian, it's a 1.1 kw (1.5 hp) motor, it's the size they recommend for this grinder. As it's designed for hogging out metal I don't think I'd want anything less, but if it's only used for leather/wood you could possibly get away with 1 hp, but the price difference between the motors isn't much. I bought the motor from Artisansupplies only because it was convenient but there's a place on ebay called Conon Motors, in Vic, and they have a good range at what appears to be good prices (unless you can find one locally maybe). If I go ahead with modding my lathe I'll get the motor from them. I bought the VFD from them ($200) but there are others on ebay for around $100 and I've found good reports on them. I think if I buy another I'll try one of the cheaper ones. Putting the VFD in a separate case is a good idea, as you say it protects it and once it's set up you don't really need to access it, all you do is fit remote  start/stop and speed controls, all done by programming.

My background is in electronics but the programming had me scratching my head for a while as the terminology was a bit new to me. I watched a few vids on youtube where guys had fitted them to lathes and that helped me understand the basic ideas. Most of the settings don't need to be changed for our needs, basically just add the motor parameters (volts, phase, current, hp etc, all of which is on the motor nameplate) and that's it. Depending on the VFD type it may be necessary to set the voltage input, I didn't have to on mine. The trickiest part was working out the settings for the remote controls, but like a lot of things it was fairly obvious afterwards!

Anything you want to know just ask.

[Matt S]

My little 1x30 grinder suddenly feels very inadequate. I'm jealous. Looks like a real workhorse!

If I can figure out a place to place it I might just have to upgrade...

[dikman]

Matt, a 1x30 can be very useful (bigger isn't always better ). I've had the other one for over 30 years and I've found that I actually use a belt grinder quite a bit, but the main reason for lashing out on this is to get the variable speed, as there's no easy way to vary the speed of a single phase grinder.

[RockyAussie]

14 hours ago, dikman said:

Putting the VFD in a separate case is a good idea, as you say it protects it and once it's set up you don't really need to access it, all you do is fit remote  start/stop and speed controls, all done by programming. 

  Electronics is definitely not one of my strong points. I have to ask where I would get one of them remote start stop speed control things and exactly what I should ask for when ordering it? Thank you again for the above information. I am sorry to admit that I think I will be back with some more questions on this as I get some it together.

[dikman]

Unfortunately you don't just buy a remote unit made up (at least not from the store). It consists of a potentiometer (I used 10 kohms), a knob, a switch and a box to mount it in, all of which are available from Jaycar, if they're handy, or online. Some of the VFD's have a removable control panel but I don't think it's a good idea to try and mount it remotely. I used a 3-way switch to give me forward and reverse but after wiring it up it struck me as pretty pointless having the grinding belt going backwards!! I'll probably replace it with a simple on-off switch. Pity we don't live closer, instead of 3,000 kms or so, but I'm happy to help in any way I can. If you get stuck with the remote bit I can make you one and send it up.

I've been looking at the cheaper VFD's on ebay and all of them that I looked at had 220v input and 318v for the 3-phase, and while they obviously work we use 240v and 415v for 3-phase - which the one I bought from Conon is rated for. I'm thinking that I should buy another one of those for the lathe (I'm undecided). I noticed that the lathe motor has a squeak, which is not good.