Excellent video, you have done such and great job eliminating the errors, the only thing I can think of is that the face of the cutter is not flat and no matter what you do it will never run true If it is dished, then there would be at least two highs and two lows for every rotation of the spindle and not just one ?
@@seamusbolton215 Thank you. The diamond wheels were cheap so I doubt they're perfect. Since I made this video I've given the diamond wheel more use and have found it's excellent for hogging off material, the chips come off silver so it cuts cooler, but it gives a poor finish so I go back to a white wheel for the final polish on the tool. I have another potential solution to the wonky spindle, but its a lot more drastic and is in the queue for the subject of a video, when I get time!
I mounted one of these cup wheels onto a cutter grinder I made and went through a similar process but in the end found the bore was causing most of the runout. After boring it out and remaking a mounting washer it is still not perfect but considerably better than it was.
That was the original plan. The diameter of the bush that fits in the bore came out concentric when mounted on the grinder so I decided to turn it to size on an arbor on the lathe. There are no graduations for the table feed on the grinder and the handle isnt on much of a gear reduction, so precise diameter control would be difficult turning it on the grinder. The face of the bush that seats against the rear of the cup wheel was turned as you suggest. Strangely it didnt seem to reliably remount with that face running true.
Thanks Robert, I’d be interested to see what you do when mounting resin bonded wheels, I have yet to find a cup wheel that isn’t all over the place including branded ones.
Thanks for watching. I've got a resin bonded wheel on the other end of the motor spindle. It works but, as you say, runs out a bit. The bit problem with them is the corner is quite rounded and I'm after a sharply defined edge for splitting drill points, hence the electrocoated wheel. I've tried truing up the bonded wheel with several things, a devil stone (I think its silicon carbide) and even brifly with a diamond dresser, all to no avail. The bonded wheel seems to glaze too, which is not good.
Morning Robert, I have also bought one of these wheels for a future grinding project, this has given me some things to consider. Thanks again for the content. I have tried to contact you about the spur gear you might be able to help me with.I used your email on your about page, but to no avail, I don't think I typed it incorrectly Thanks Jon
Hi Jon, thanks for watching and commenting. Regards the spur gear, I haven't seen a msg from you, sorry. Please try again, I'll do my best to help you out. I've received other mails on that address, so it does work. The address should be tpsw@catsparadise.me.uk
I've not come across either of those techniques. There's not much material that can be removed on this style of wheel, unlike on a resin bonded diamond wheel.
I hope the spindle isnt that sensitive to a light tap. I'm just tapping the key home with a soft bronze bar to seat it correctly, but its another avenue to explore if the wheel doesnt grind nicely. I'm not a fan of mounting the wheel direct to the motor spindle, but I guess the machine was designed down to a price
I think the worst thing you did was mount the new wheel face to the face plate instead of the internal machined face this would show if the cone was running true the rough surface however would not.
It was deliberate to mount the face of the wheel as a reference, after all that is what will be doing the grinding. I wonder if the front face of the cup wheel, where the front spindle washer sits, is not true and is pulling everything out of line as the nut is tightened. Or maybe the motor bearings run out, although I have replaced them recently.
Hello. I remember you saying that you were going to do an undercut but I don’t think I saw it? I’m probably wrong, just thought I’d say it. Anyway, really enjoying your content and look forward to the next video. Greetings from Amsterdam. 👍
Someone was paying attention🤣. You are of course correct. I think when skimming the face of the bush on the grinder I fed in a bit extra to create a partial undercut. I had some video of me checking the contact pattern between bush and cup wheel which was only on the periphery so the chamfer on the cup wheel was sufficient, but that footage didnt make the final edit as it was getting too long. Thanks for watching and commenting.
Thats the plan! I saw one of these wheels on Max Grants channel and thought it might be worth trying as theyre cheap direct from the far east. Thanks for watching!
Yep, I agree. The motor shaft is bent. I dont want to try and straighten it as its a double ended motor and theyre not easy or cheap to come by. The optimum solution is to make a new spindle and drive that from the motor. Another project...
Excellent video, you have done such and great job eliminating the errors, the only thing I can think of is that the face of the cutter is not flat and no matter what you do it will never run true
If it is dished, then there would be at least two highs and two lows for every rotation of the spindle and not just one ?
@@seamusbolton215 Thank you. The diamond wheels were cheap so I doubt they're perfect. Since I made this video I've given the diamond wheel more use and have found it's excellent for hogging off material, the chips come off silver so it cuts cooler, but it gives a poor finish so I go back to a white wheel for the final polish on the tool.
I have another potential solution to the wonky spindle, but its a lot more drastic and is in the queue for the subject of a video, when I get time!
I mounted one of these cup wheels onto a cutter grinder I made and went through a similar process but in the end found the bore was causing most of the runout. After boring it out and remaking a mounting washer it is still not perfect but considerably better than it was.
That's very interesting, thanks. Maybe I will bore it out and try again with a new bush turned in situ.
IMt is very interesting to see the work that you did.Thank you.
Thanks for watching!
Make your adapter a little oversize, mount it on the grinder spindle, then turn it to size and true on the grinder itself.
That was the original plan. The diameter of the bush that fits in the bore came out concentric when mounted on the grinder so I decided to turn it to size on an arbor on the lathe. There are no graduations for the table feed on the grinder and the handle isnt on much of a gear reduction, so precise diameter control would be difficult turning it on the grinder. The face of the bush that seats against the rear of the cup wheel was turned as you suggest. Strangely it didnt seem to reliably remount with that face running true.
Thanks Robert, I’d be interested to see what you do when mounting resin bonded wheels, I have yet to find a cup wheel that isn’t all over the place including branded ones.
Thanks for watching. I've got a resin bonded wheel on the other end of the motor spindle. It works but, as you say, runs out a bit. The bit problem with them is the corner is quite rounded and I'm after a sharply defined edge for splitting drill points, hence the electrocoated wheel. I've tried truing up the bonded wheel with several things, a devil stone (I think its silicon carbide) and even brifly with a diamond dresser, all to no avail. The bonded wheel seems to glaze too, which is not good.
I made a pair off of those for my tool post grinder. Came out pretty nice
Did you get them to run true? If so, well done. Thanks for watching.
@@ThePottingShedWorkshop yes I took them to 5000 rpm with no problem. I filmed it under my video grinding jaws
Morning Robert, I have also bought one of these wheels for a future grinding project, this has given me some things to consider. Thanks again for the content.
I have tried to contact you about the spur gear you might be able to help me with.I used your email on your about page, but to no avail, I don't think I typed it incorrectly
Thanks Jon
Hi Jon, thanks for watching and commenting. Regards the spur gear, I haven't seen a msg from you, sorry. Please try again, I'll do my best to help you out. I've received other mails on that address, so it does work. The address should be tpsw@catsparadise.me.uk
I think the usual
Method for truing diamond wheels is to dress with a bit of moly or at a pinch a bit of soft steel.
I've not come across either of those techniques. There's not much material that can be removed on this style of wheel, unlike on a resin bonded diamond wheel.
just a thought,,, when you knock the key into the shaft with the brass lump is that enough to push the shaft out of alignment??
I hope the spindle isnt that sensitive to a light tap. I'm just tapping the key home with a soft bronze bar to seat it correctly, but its another avenue to explore if the wheel doesnt grind nicely. I'm not a fan of mounting the wheel direct to the motor spindle, but I guess the machine was designed down to a price
I think the worst thing you did was mount the new wheel face to the face plate instead of the internal machined face this would show if the cone was running true the rough surface however would not.
It was deliberate to mount the face of the wheel as a reference, after all that is what will be doing the grinding. I wonder if the front face of the cup wheel, where the front spindle washer sits, is not true and is pulling everything out of line as the nut is tightened. Or maybe the motor bearings run out, although I have replaced them recently.
Hello. I remember you saying that you were going to do an undercut but I don’t think I saw it? I’m probably wrong, just thought I’d say it. Anyway, really enjoying your content and look forward to the next video. Greetings from Amsterdam. 👍
Someone was paying attention🤣. You are of course correct. I think when skimming the face of the bush on the grinder I fed in a bit extra to create a partial undercut. I had some video of me checking the contact pattern between bush and cup wheel which was only on the periphery so the chamfer on the cup wheel was sufficient, but that footage didnt make the final edit as it was getting too long. Thanks for watching and commenting.
After you have used it a faw times you will know if it works or not.
And if it doesn't, just make it better :)
Thats the plan! I saw one of these wheels on Max Grants channel and thought it might be worth trying as theyre cheap direct from the far east.
Thanks for watching!
@@ThePottingShedWorkshop I use the same one on my milling machine. It works really well.
Thanks for the video 👍
You're welcome. Thanks for watching.
Check the shaft of the motor for run out.
Yep, I agree. The motor shaft is bent. I dont want to try and straighten it as its a double ended motor and theyre not easy or cheap to come by. The optimum solution is to make a new spindle and drive that from the motor. Another project...