Low cost small wheel attachment for your NWG

[ERIK KNIVES]

Wow man, your grinder really turned out very nice. Clean. I like your live spindle approach to the small wheel.

I used some Vespel polymer, which is used for high speed bushings, on a dead spindle. Pictured is the 1/2", though I have a larger one too. These have a lot of miles on them. I do wish they were more compliant.

Nathan,

I love that approach, I would have initially done something similar if I had your knowledge of available materials. I made a flat grinding jig that I think you may appreciate. It's different from the jigs (cheaters) I've seen and although I am a novice, I put down a decent flat grind my first time out with it. I will post some pics in a few days.

 

[ERIK KNIVES]

I got some 1/2" rod at the local hardware today, and I was able to find some scrap 1/4" |_| shaped brackets that I should be able to mount my flange bearings on when they come in. I also got some 6" spiral sewn buffing wheels that I'm going to mount opposite of my sanding spindles for a makeshift buffer. All in all, I should have less than 50 bucks tied up in this by the time everything gets put together.

K.T.A.G.,

I like the multifunction idea, I plan on using a longer drive shaft on my grinder and adding a 9" sanding/grinding disk beyond my drive wheel. If I may, I think the problem with your plan is that as soon as you push something against the buffing wheel, the shaft will slow down or stop and the rubber bushing will spin with the belt and melt. My rubber bushings only have enough grab to spin the shaft and the bearings, nothing else.

Maybe I don't understand your layout, but I couldn't do that with mine.

Erik

 

[SteelSlaver]

Nice idea and execution. Sure it does a great job.

I have one of Robs small wheel attachments and I don't think it is over priced. First there is the cost of the aluminum. Then cutting it up and machining. It might not be cheap, but, that hardly makes it overpriced. Rob, has provides us with first class equipment and he has always been willing to help those who wish to make equipment and attachments on their own.

 

[Drew Riley]

Knife to a gunfight,

Good luck with yours, I can say mine is working very well now that I have had some time to run it though it's paces.

My suggestion is to use some low viscosity grease in those flange bearings to keep them loose (something for cold temperatures). The stuff I originally put in was too heavy and dragged before it warmed up and also heated up the shaft quite a bit - enough that after heavy use the rubber bushing began to smell. That only happened once, I have since thinned out the grease and it runs cooler. The small wheels cause very high rpm to the shaft - on my grinder I only run the small wheels on my first two speeds (mainly 1st).

Erik

Thanks for the advice. I can't wait for my bearings to get here!
Looks like the brackets I found are going to be a little too short for the length of square tube I have, so I'm probably just gonna use a left over piece of 1/4" square tube that I had left over from my NWGS base to mount the flange bearings to. It'll be a little heavier, but I figure the added mass will help cut vibrations that much more.

I also went ahead and made some "stop collars" by drilling the centers out of some 1/2" nuts so they slide over my rod, and then tapping some set screws into the faces. I'll probably end up getting some lock washers to help hold the rubber in place, but I'll see how it works without.

I'm so glad I happened upon this thread. Now I can check off my much needed small wheels and buffer, and all for less than 50 bucks! (not including the tap and die...)

I'll try to post some pics when I get it all set up.

 

[Drew Riley]

K.T.A.G.,

I like the multifunction idea, I plan on using a longer drive shaft on my grinder and adding a 9" sanding/grinding disk beyond my drive wheel. If I may, I think the problem with your plan is that as soon as you push something against the buffing wheel, the shaft will slow down or stop and the rubber bushing will spin with the belt and melt. My rubber bushings only have enough grab to spin the shaft and the bearings, nothing else.

Maybe I don't understand your layout, but I couldn't do that with mine.

Erik

Yeah, I definitely thought of that possibility. I may try using some lock washers on the rubber, or making a different "drive wheel" that will lock onto the shaft on the sanding belt side. If all else fails, I can also mount a pulley and run a belt to my motor, or I'll just mount the buffing wheels to my shopsmith and forget about multi-purposing. I'll have to play with it for a while and see. I'll probably be using a pretty light touch while buffing anyway.

 

[NickWheeler]

I really like your ingenuity!!!


I've said it before and I will always say it again... knifemakers sure are a bunch of "CAN DO" type of guys (and a few gals!) Your work here is proof positive of that! :thumbup:

 

[ERIK KNIVES]

Nice idea and execution. Sure it does a great job.

I have one of Robs small wheel attachments and I don't think it is over priced. First there is the cost of the aluminum. Then cutting it up and machining. It might not be cheap, but, that hardly makes it overpriced. Rob, has provides us with first class equipment and he has always been willing to help those who wish to make equipment and attachments on their own.

I agree, I've bought 4 wheels from Beaumont and they all all worth it. Without them, I wouldn't have a grinder. The KMG is also awesome and worth it, I just can't afford it.

Erik

 

[ERIK KNIVES]

I really like your ingenuity!!!


I've said it before and I will always say it again... knifemakers sure are a bunch of "CAN DO" type of guys (and a few gals!) Your work here is proof positive of that! :thumbup:

thanks Nick,

I love sites like this becuase so many people have ideas and experience to draw from, and so many of them are willing to share their success and failures.

Erik

 

[butchesforge]

I did basicly the same thing,but not as pretty as yours.I used pillow blocks and a piece of 1/2" cold roll and slipped rubber tubing over it,not high tech but it works---Regards Butch

 

[ERIK KNIVES]

I would have used pillow blocks if I thought of it. Square cuts, less material, and less weight with a plate mounted above or below the tool arm. Thanks, Erik

 

[Tippet]

As I've said before, it's a amazing what you can do with a little welding on the NWG

 

[Drew Riley]

Well, here's a couple pics of my small wheel attachment with a 3/4 spindle on it. Overall, it's not bad. I still need to get some lighter visc. grease for the bearings. I scrapped the buffer side. It's not that it didn't work, but there was just a little too much vibration for my tastes, and since I have another machine and I can turn into a makeshift buffer, I decided not to mess with it.

I sill need to work out some tracking issues here and there, but overall, it seems effective for the mean time. I probably will end up getting the KMG small wheel set up one of these days, but I'm gonna have to raise a lot more money. This will definitely get me where I need to go until then though.

 

[ERIK KNIVES]

Well, here's a couple pics of my small wheel attachment with a 3/4 spindle on it. Overall, it's not bad. I still need to get some lighter visc. grease for the bearings. I scrapped the buffer side. It's not that it didn't work, but there was just a little too much vibration for my tastes, and since I have another machine and I can turn into a makeshift buffer, I decided not to mess with it.

I sill need to work out some tracking issues here and there, but overall, it seems effective for the mean time. I probably will end up getting the KMG small wheel set up one of these days, but I'm gonna have to raise a lot more money. This will definitely get me where I need to go until then though.

I'm glad it's working. It looks like you could move your 4x4 square tubing to the other side of the tool arm and closer to the belt. If your bearings are closer to where the belt rides, it will be stiffer and cause less stress on the shaft. That may help your tracking issue and overall vibration. To check the overall alignment of your drive and small wheel, try running the belt straight to the small wheel and bypass the tracking wheel. I had a tracking issue and did that with my 8" and small contact wheels to isolate the problem. The belt tracked fine between the drive and contact wheel completely bypassing the tracking wheel. So, I went to the tracking wheel assembly and and found I had a slight issue on the horizontal plane, it was not aligned as well as it should be. I bored out the bolt holes a bit and adjusted accordingly. Now my tracking wheel looks level from the front while running all attachments and tracking is no longer an issue.

Erik

 

[Drew Riley]

I'm glad it's working. It looks like you could move your 4x4 square tubing to the other side of the tool arm and closer to the belt. If your bearings are closer to where the belt rides, it will be stiffer and cause less stress on the shaft. That may help your tracking issue and overall vibration. To check the overall alignment of your drive and small wheel, try running the belt straight to the small wheel and bypass the tracking wheel. I had a tracking issue and did that with my 8" and small contact wheels to isolate the problem. The belt tracked fine between the drive and contact wheel completely bypassing the tracking wheel. So, I went to the tracking wheel assembly and and found I had a slight issue on the horizontal plane, it was not aligned as well as it should be. I bored out the bolt holes a bit and adjusted accordingly. Now my tracking wheel looks level from the front while running all attachments and tracking is no longer an issue.

Erik

Yeah, that's exactly what I plan to do with my tooling arm, to shave a couple of inches more off the shaft. As it is, the vibration is really so minimal that I can set an object on the 4" tube and it won't vibrate off. I don't mind taking up slack where I can though.

As for the tracking issues, part of it has to do with the play between the tool arm and my socket. Since I had to use my tool rest socket which tighted from the top, I have a little left to right play. Tapping a hole in the side (or just shimming the gap) would fix that part though.

I have had a little bit of tracking issues in the past though, which I was able to mitigate by adjusting my drive will a little, but I think I do need to calibrate my tracking wheel. One side has actually worn smooth, so I'm not really sure what to think about that. I tried to initially square it up with my drive wheel, IIRC, but maybe it's not as square right now as I think. I'll definitely check it again.

As for my small wheel attachment, I made the mistake of pumping some grease into the bearings that I thought was a low enough visc., but it seems to have slowed things down to where the belt starts slipping. So now I'm trying to figure out how to "degrease" the bearings before I just have to buy new ones. :thumbdn:

At anyrate, it was working great for a while! A few adjustments and it should be adequate until I can raise enough funds to get something better.

 

[Drew Riley]

Well, I got things running smooth again. Went ahead and moved the toolarm to the other side so that I could shorted the rod up some more. The tracking issues seem resolved as well. It helps if I push the tool arm all the way to one side of the socket.

Now I just need to get some low visc. grease, but I can't seem to find any at the local hardware or tractor supply. Seems to all be roughly the same kind of stuff. Any suggestions for a brand?

 

[ERIK KNIVES]

Well, I got things running smooth again. Went ahead and moved the toolarm to the other side so that I could shorted the rod up some more. The tracking issues seem resolved as well. It helps if I push the tool arm all the way to one side of the socket.

Now I just need to get some low visc. grease, but I can't seem to find any at the local hardware or tractor supply. Seems to all be roughly the same kind of stuff. Any suggestions for a brand?

I shot some WD40 in the bearings when the were warm and running and that loosened it up a bit. I'm going to get some AeroShell 22 grease online.

 

[Drew Riley]

I shot some WD40 in the bearings when the were warm and running and that loosened it up a bit. I'm going to get some AeroShell 22 grease online.

Yeah, that's basically what I had to do... I just used some penetrating oil to clean out as much of the grease as I could, and I put a larger spindle on so the sanding belt would grab and turn the rod better. It eventually loosened up enough to use the 3/4 spindle again. I'll have to look into trying that Aero 22 stuff. Unfortunately, shipping seems to be as much as the tube! I guess it's worth it if it keeps me from buying another set of bearings and roughly the same cost though.

Thanks for all the friendly help and advice thus far.

 

[Drew Riley]

I used the small wheel attachment tonight, and it looks like I have to warm it up with the 3" wheel before I can use the 3/4". Sooo.... I went ahead and placed an order for the Aeroshell 22. I'll post the results when it get's here. Maybe have to lube the bearings a couple times to purge the old stuff out though.

We'll see.

Anyway, it seems that I'm now having some additional tracking issue that were not present before when I use any of my other attachments. I.E., if I start the 8" contact wheel on high speed, the belt immediately tracks right off. At medium speed, it seems to stay most of the time, but if I bear down on the side of the wheel too much while grinding, it tracks right off too. Seems like the drive and contact wheels are still lined up, so I'm not really sure what to think about it. I guess I need to fiddle with it some more. It's kind of frustrating at the moment, not knowing the cause.

I thought maybe the drive wheel wore down a little when the sanding belts slipped on the small wheel, but I can still feel the ridges, so I don't think THAT's the problem.
Hopefully I can figure it out without having to spend any more money on the thing...

 

[ERIK KNIVES]

There is no way your drive wheel wore down from the belt slipping off because of alignment issues. I could see your tracking wheel taking some minor wear over long term use if it was not parallel to the ground and the belt ran on one side of it for an extended period. Even then you should be fine once you get the right alignment.

I used 1/4" wall on my 2" tool arm adapter. I found that 1 1/2" square tube I bought will fit in there very nicely if it was oriented so the weld seams are on the same side. I don't know if using the 1/8" wall could create enough play in the tool arm to make an alignment issue. I have not heard of anyone having problems sticking to the plans in that regard.

Is your abrasive belt tight enough? Some of my belts have about 1/16th side to side travel which looks normal in the videos I have seen. Other belts I use have no side to side travel, but they all behave poorly if there is not enough tension. I played with different springs to get the tension I was looking for. I have read that the KMG has a really stiff spring on it, so much that many add an extended arm for leverage when changing belts. I did the same thing on mine, I think my spring set up pushes close to 50 pounds when it is compressed.

Make sure your belt is fairly tight.
Do your best to figure out the alignment. If you are in good shape, you can run directly from your drive wheel to your 8" contact wheel or small wheel and be close enough to stay on the wheels (completely bypassing the tracking wheel). The tracking wheel should be working to fine tune belt location, not overcome bad alignment.
Make sure your bearings on your small wheel are nice and parallel and not binding. - Loosen the mounting bolts and check how well they spin. They should spin just as well when the bolts are tightened. Even if they bind or are causing enough friction to slip the rubber bushing on the shaft, the belt should still track fine, you will just melt your rubber bushing. PS, make sure that your small wheel shaft is clean and dry so it's not slipping for that reason, although alignment and belt tension really seems like the overall problem here. Good luck.

 

[ERIK KNIVES]

I used the small wheel attachment tonight, and it looks like I have to warm it up with the 3" wheel before I can use the 3/4". Sooo.... I went ahead and placed an order for the Aeroshell 22. I'll post the results when it get's here. Maybe have to lube the bearings a couple times to purge the old stuff out though.

We'll see.

Anyway, it seems that I'm now having some additional tracking issue that were not present before when I use any of my other attachments. I.E., if I start the 8" contact wheel on high speed, the belt immediately tracks right off. At medium speed, it seems to stay most of the time, but if I bear down on the side of the wheel too much while grinding, it tracks right off too. Seems like the drive and contact wheels are still lined up, so I'm not really sure what to think about it. I guess I need to fiddle with it some more. It's kind of frustrating at the moment, not knowing the cause.

I thought maybe the drive wheel wore down a little when the sanding belts slipped on the small wheel, but I can still feel the ridges, so I don't think THAT's the problem.
Hopefully I can figure it out without having to spend any more money on the thing...

Try this, once you have confirmed that your drive wheel and 8" contact wheel are reasonably aligned, put the belt on all three wheels and stand above your grinder looking down at the tracking wheel. Using the belt as a reference line, you should be able to see if your tracking wheel is rolling in line with the other two.