MDF sharpening discs

[LeTuB]

Roughly cut 8'' discs in a scrap 1/2'' MDF sheet.

Then glue by pair

Of course it's better if you have directly 1'' thick MDF
Drill center, then mount on the grinder

Give them the shape you want with a wood file and sandpaper (grinder ON) depending on what you want to sharpen
Here I rounded the edges for my concave BH

 

[Fuse Dude]

Roughly cut 8'' discs in a scrap 1/2'' MDF sheet.

Then glue by pair

Of course it's better if you have directly 1'' thick MDF
Drill center, then mount on the grinder

Give them the shape you want with a wood file and sandpaper (grinder ON) depending on what you want to sharpen
Here I rounded the edges for my concave BH

Glue the 220 grit silicon carbide powder on one of the discs with wood glue

To be continued....(missing pictures)

I'm liking your style

 

[Halfstep]

Make sure to get some wax and keep the grit wheels coated as it helps to keep them cool when sharpening. Also get some white rogue buffing compound for the non-grit wheels.

 

[LeanMachine]

This is what i use for burr removal on BHs and knives. I just use buffing compound on mine. Works insanely well.

Sent from my SM-G991U using Tapatalk

 

[BTaylor]

Where you get that grit powder?

 

[Iron_llama]

Do you freehand it or use a jig? I've got a Shopsmith, I could make a rod with several grits to put on the lathe.

 

[LeTuB]

...continued...
coat the disc with a good amount of wood glue then pour it with the silicon carbide powder, while turning the wheel by hand.
Put a sheet of paper under to retrieve the powder in excess
let dry for 24h


After 24h, coat the grit with bee wax (turn the wheel by hand)


Turn on the grinder, use a scrap blade to gently heat the wax until you obtain an uniform coating


the other disc is coated with polishing paste (rouge)


few pass of each disc gives you a razor sharp edge, you'll need to train a bit to maintain the angle

 

[LeTuB]

Where you get that grit powder?

you'll find it on amazon

Amazon.com : silicon carbide powder

 

[LeTuB]

you can even sharpen replaceable blades (QAD exodus for exemple)

 

[Halfstep]

When it comes time to re-grit the wheel, I find that using an angle grinder works well. Turn on the grinder with the paper wheels and then turn on the angle grinder and grind the paper wheels until clean. Since both grinders are turning at the same time, this ensures that the wheels will remain true and it will quickly remove all the old wax and grit and also it will true up any out of roundness that may have developed from hard use. Then when I re-grit, I put an EVEN and THIN coat of glue on the freshly cleaned paper wheel. I use Elmers's glue and then QUICKLY sprinkle the new grit onto the wheel. I put a piece of paper under the wheel to catch the unused grit. It is important to get the paper wheel gritted quickly as the glue starts to dry fairly quick. Once the paper wheel is re-gritted, I then take a cordless drill and install a 2–4-inch grinding stone or something similar. Then I zip-tie the trigger to turn slowly and then place the drill so that the 2-4-inch grinding stone is up against the deburring wheel. This way, the freshly re-gritted paper wheel will turn slowly as it dries. I do this for 15-20 minutes until the glue is set. If you don't keep the freshly re-gritted wheel turning slowly, the glue will start to sag and run toward the bottom of the wheel creating lumps. DO NOT turn on the grinder while the glue is wet as it will sling the glue and grit off of the wheel and make a big mess, been there done that. But with the cordless drill turning it slowly, it will dry evenly without any lumps from the glue sagging.

 

[eastchannel]

When it comes time to re-grit the wheel, I find that using an angle grinder works well. Turn on the grinder with the paper wheels and then turn on the angle grinder and grind the paper wheels until clean. Since both grinders are turning at the same time, this ensures that the wheels will remain true and it will quickly remove all the old wax and grit and also it will true up any out of roundness that may have developed from hard use. Then when I re-grit, I put an EVEN and THIN coat of glue on the freshly cleaned paper wheel. I use Elmers's glue and then QUICKLY sprinkle the new grit onto the wheel. I put a piece of paper under the wheel to catch the unused grit. It is important to get the paper wheel gritted quickly as the glue starts to dry fairly quick. Once the paper wheel is re-gritted, I then take a cordless drill and install a 2–4-inch grinding stone or something similar. Then I zip-tie the trigger to turn slowly and then place the drill so that the 2-4-inch grinding stone is up against the deburring wheel. This way, the freshly re-gritted paper wheel will turn slowly as it dries. I do this for 15-20 minutes until the glue is set. If you don't keep the freshly re-gritted wheel turning slowly, the glue will start to sag and run toward the bottom of the wheel creating lumps. DO NOT turn on the grinder while the glue is wet as it will sling the glue and grit off of the wheel and make a big mess, been there done that. But with the cordless drill turning it slowly, it will dry evenly without any lumps from the glue sagging.

I dismount the disc, glue and roll in a vee folded newspaper with grit, seems like mess.. Let it dry a day and dress it with the back of an old wrench. Bee's wax is a great lube for this.

 

[Halfstep]

I dismount the disc, glue and roll in a vee folded newspaper with grit, seems like mess.. Let it dry a day and dress it with the back of an old wrench. Bee's wax is a great lube for this.

I tried it that way, taking the wheels off and reinstalling them but it seemed too problematic. Once the wheels were reinstalled, they would be a little off center. It was difficult to get them centered well. So, I just mount them and leave them on and clean and re-grit them. I buy and use a few tubes of bowstring wax as it is bee's wax.