Cost saving methods for grinding

[MotorbikeMan]

I have one of these in my workshop..just a spinning disc on the end of a reversible motor......IMO this is a very underestimated tool!!! I can get a true flat fininsh with ease, especialy with a small blade knife, as its not necessary to draw the blade across the grinder, like a 2 inch wide grinder....with a bench disc grinder I just hold the blade still.

Its possible to grind a knife with some nice curved transitions with this machine....and because you not paying for belts, its a fraction of the cost..........In fact, I think that it could make an expensive belt grinder obsolete once you learn what you can do.....But a 'reversible' motor is a MUST.....


Could you explain why Coutel, I'm thinking of getting a motor to make one of these which would be bigger and heftyer than the drill I'm using at the mo, also what would be good for the disc itself, wood, mdf, metal?

[Kevin]

Could you explain why Coutel, I'm thinking of getting a motor to make one of these which would be bigger and heftyer than the drill I'm using at the mo, also what would be good for the disc itself, wood, mdf, metal?


Jon..I will go and snap a photo and show you...back in a mo.

[ZDP-189]

Kevin, you're right. This is the disc sander.

http://www.uberlevel.com/homepages/zdp-189/workshop/disc.jpg

It'll have a powerful single phase motor and I may install a speed controller. The disc alone has a lot of mass and so it will happily hog through most any unhardened steel, or whatever.

I'll probably put a rag buffer on the other end, due to direction of rotation and proximity to the other disc to the left of it (see new floorplan, to follow.).

I'm not sure that the cost advantage if so great. I have the horizontal mill which uses cheap off-cut discs and the linisher has a relatively short belt. I also tend to use the 1" belt sander for activities like stock removal, and those belts are under 40p each, vs. 15p for a sheet of coarse wet 'n dry. It's also a pain in the behind to change stuck-on discs.

MBM, you need a bidirectional motor because you can only use one side of the disc; the other throws grit in your eyes and vibrates your workpiece out of your hands. As you have to grind blades edge up, you need to be able to spin the motor the other way.

[Kevin]

Kevin, you're right. This is the disc sander.

..........
I'm not sure that the cost advantage if so great. I have the horizontal mill which uses cheap off-cut discs and the linisher has a relatively short belt. I also tend to use the 1" belt sander for activities like stock removal, and those belts are under 40p each, vs. 15p for a sheet of coarse wet 'n dry. It's also a pain in the behind to change stuck-on discs.

.

Good one.

Belts for my 2 x 72 run at about $6.oo each....It will take maybe 5 or 6 belts to grind and finish a knife easily...In fact, belts are my biggest consummable cost!!!

After forging, I can get thru a 36 grit belt in minutes just grinding the scale off....so a few minutes with a hand grinder saves a lot of money......

here is a link to my disc grinder..

http://www.britishblades.com/forums/showthread.php?p=104029#post104029

[JohanB]

a very "money saving" way of grinding blades is a grinding wheel...those rocks...they are really nice and lasts ages..

[shing]

I do all my initial blade grinding with an angle grinder, its quick, and grinding discs are a lot cheaper than belts.

[Graham]

Angle grinders are great for initial grinding, but I found I got a better result when I changed from the hard disks to Flap Disk's these are available in many grades i'e 40.60.80 and are less prone to leaving furrows in the metal due to them having a flat edge, they are commonly used in car body shops to grind welds with less damage to panels and the smoother finish needs less filler. Using a 80 grit carefully I find I can go straight to a 120 grit belt saving a lot of time, the disks are long lasting and easily available well worth a try.


Graham

[ZDP-189]

This thread's taken an interesting turn. I'm going to split it and put the part on cost saving grinding methods as a separate thread outside the Matrix.

[MotorbikeMan]

This thread's taken an interesting turn. I'm going to split it and put the part on cost saving grinding methods as a separate thread outside the Matrix.
Good Call :biggthump

[Sajuma]

Angle grinders are great for initial grinding, but I found I got a better result when I changed from the hard disks to Flap Disk's these are available in many grades i'e 40.60.80 and are less prone to leaving furrows in the metal due to them having a flat edge, they are commonly used in car body shops to grind welds with less damage to panels and the smoother finish needs less filler. Using a 80 grit carefully I find I can go straight to a 120 grit belt saving a lot of time, the disks are long lasting and easily available well worth a try.


Graham

Now days I use those too. I have found that those lameldisks exist also up to 240 grit and that gives a nice finish. Only thing is that those disks block up sometimes and are pain to clean.

Juha