Angle Grinder

Fiddleback

Fiddleback

Knifemaker
Moderator
Knifemaker / Craftsman / Service Provider
Joined
Oct 19, 2005
Messages
20,010
Just got one. Are there jigs I should build? How do you secure it to a table to use as a profile grinding tool?? Safety concerns?
 
harbor freight sells a mount that turns the angle grinder into a chop saw. i have one but havent tried it out. i prefer to use mine by hand.
 
Cool. I have been using mine as a profile grinder. I've had it clamped to the table. Anybody know of a better way?
 
I clamp the blade steel down in vise grips and a table vise and hold the grinder in my hands. Still use a respirator and face shield and goggles. I've found that while gloves will keep my hands clean that they can catch on the disk- long close fitting sleeves will keep the sparks off your skin.

Make sure that disk guard is tight and won't sling around and push your thumb into the disk...come to think of it, don't touch that guard at all when the disk is spinning. And don't remove that stick handle. I guess the gloves would have provided me some early warning on the disk/thumb action, but I could have lost a thumb tip if the glove had caught under the guard and wedged my thumb between the guard and disk, so no gloves for me.

Harbor Freight has specials on 10packs of metal cutting disks and metal grinding disks. I tend to use more of the cutting disks. I've bought name brand disks at Lowes and Home Depot and not seen a difference in performance/longevity between the "good ones" and harbor freight, except that 3-4 name brand disks= one 10pack of hf disks price wise.

There's a discussion on how to profile and bevel with an angle grinder on this site somewhere.

Enjoy the new tool!
 
Geez. That does sound easier. THanks.
 
That Other Guy said:
I clamp the blade steel down in vise grips and a table vise and hold the grinder in my hands. Still use a respirator and face shield and goggles. I've found that while gloves will keep my hands clean that they can catch on the disk- long close fitting sleeves will keep the sparks off your skin.
Click to expand...

I'll second that. Clamp the blade and move the grinder. I don't know about yours, but mine is roughly a cylindrical shape- tough to clamp anywhere! But barstock, just clamp it to the bench and go to town.

The cutoff discs work faster than a bandsaw, although there are some downsides- noise, sparks, larger kerf, can only cut straight lines.

And the grinding discs I find great for profiling. Way, way cheaper than coarse grit belts, and you can get the inside of tighter radii, too (ie, the inside of a finger-groove in the handle). Again, there's a downside- leaves a messy, ragged edge. And the sparks (don't let the sparks fall on your little piles of sawdust).

Useful tool!

Mike
 
You can also get disk that are layers of sandpaper I call tiger disks. They come in a variety of grits and are very aggressive, but are easirer to do smoother work with. Care is need to avoid gouges.
 
i use an angle grinder to do the profiling as well. just put the blade in a vice and go to town.

can you post the link to the HF cuting disks?
-matt
 
The angle grinder is my workhorse too.I profile with it using cutoff wheels like so...I know the drawing is crude so bear with me.Draw your design on the steel with a sharpie and cut to the outside of the line(that'll leave roughly 1/8") Make your first cuts with the red lines.then make second cuts on a diagonal
to cut out finger grooves and curves.follow carfully with the grinding wheel afterwards.This might not be the best method but I found it better than leaning in on the angle grinder and burning off the marker lines :eek: Sorry again about the crude drawing I'm on my wifes time now;)
profile.jpg
 
To be honest, I've never used a angle grinder on blades (way easier with a bandsaw and belt grinder) but I do use one every day at work (I'm a welder/fabricator). What everyone else has said will work (how well depends a lot on you) but if you want to smooth out your grinds, and don't have a belt grinder, get some sanding discs. Basically they're a flexible plastic or rubber backing pad that attaches to the spindle on your grinder. Sanding discs (the ones I used were Klingspor) attach to the face of the pad by a nut that screws onto your grinder's spindle (through the disc and pad clamping everything together) and come in 36-100 gr. There are also emery pads that attach (hook and loop) to a different backing pad and can give you almost a mirror finish (the ones my shop supplies are 3M). I use these for blending welds and prepping sheet metal joints for paint or powder coat. The flapper-type sanding discs are okay, but they tend to leave a concave surface (and they cost a lot more than the flat-disc type). Hope this helps, if you need some pics/links to get a better idea, let me know and I'll try to find some.

Have a good one,
Nathan Dallyn


Make sure that you wear wraparound type safety glasses if not a full face shield whenever you use an angle grinder! This is a welder talking from the experience of having doctors picking bits of steel out of my eye with a needle (one of the least fun experiences of my life). You only have two eyes and you need both of them to make knives (depth perception is a good thing). And most definitely WEAR GLOVES, especially when using cutting discs (1/16-3/32 zipcuts) as they tend to shatter under only very slight side-loading. I cannot count the number of apprentices and jouneymen I've seen get cut or burnt because they "were just gonna do something quick" and didn't bother to leather up. If you're worried about your gloves catching, wear tighter gloves. I'd rather lose a layer of leather than a layer of skin. And lastly, if at all possible grind so that if the disc digs in and catches, the grinder jerks away from you rather than in to you. Looking down from the top, discs spin clockwise. If you catch the left side (7-12 o'clock) the grinder will move backwards, if you catch the right side (1-6 o'clock) the grinder moves forward (this being away from you). Put it into the wall, not into your guts.
 
Ditto the good eye protection and learn which way the grinder is going to fling the sparks and grit and remember that this stuff will richocet off and come back and get you. The needle in the eye sucks and if it starts rusting they have another nice little bur tool to help remove that. Good eye protection is a constant when working power tools especially around metal.
 
i also suggest something to cover your whole head (non flamable cloth) ive gotten so many hot sparks bounce off the wall and hit my ear of side of my face where the shield ends and its not a pleasent feeling.

-matt
 
i find that when your making a vertical cut and have the angle grinder turned sideways and are cutting from top to bottom, be sure to turn it so the motor is on the left and the disk is on the right. this way the sparks dont fly towards you but away from you. if your do the same cut but are going straight into it with the grinder, then turn it the opposite way so the sparks fly downwards. i find wearing a long sleeve shirt with the gloves helps out too. you wont get little sparks flying onto your arm. hope that helps out.
 
Great tips guys. Thanks.

Oh. My shop is pretty well equipped I'll try to dig out pics. Although my belt grinder is only a 1x42. I'm going to remedy that soon.
 
just dont buy disks from the local expo or fair gatherings ive had them explode while grinding and even with all the protection you can have that still hurts. also your shop will get dirty fast from the grinder sparks and grit. i use it for final profiling after the band saw and primary bevels and to remove alot of the meat on the sides when im going to make a flat ground if you dont have a belt sander you can use a agressive file to true up the flats and use a sharpy to show where the dips are on the flats
this a filing guide helps with the racasso edge you can get it from jantz supply
 
I don't know how to do the link gimmick, soooo...Do a search for "metal cutting" on the harbor freight website. 4 1/2" 10 pack on sale for $3.49 right now. Don't even look at the angle grinder prices if you've already gotten a brand name one- you'll just get upset, although you can console yourself that you have a brand name one...
 
As far as faceshields go looks like the newest and best thought out if a little expensive at $50. Of course EYES are priceless. Combining this with wrap-arounds would put a lot of material between whatever is disintegrating and your eyes/face/teeth/throat/neck.

http://i5.photobucket.com/albums/y166/synthesist/WoodcraftsBionicFaceshield.jpg

Bionic Face Shield (from Woodcraft)

Revolutionary design combines superior protection and all-day comfort. Maximize your protection, vision, and your comfort level with the Bionic Face Shield.
• Extended top-of-head coverage
• Superior optics and full face polycarbonate visor
• Visor features scratch resistant and anti-fog coatings
• Built-in chin protection deflects flying particles and debris
• Comfortable foam back pad
• Easy-to-set ratcheting headgear locks into place for a secure fit
• Headgear adjusts to your choice of 4 visor angles and 2 depth adjustments and the headband is removable and washable
• Flips down for hands-free availability
• Lightweight and comfortable for extended wear
• Can be comfortably worn with most goggles and respirators
• Quick, easy, economical visor replacement
• Meets ANSI Z87.1 and CSA Z94.3 standards.
 
PimpinSquee said:
i find that when your making a vertical cut and have the angle grinder turned sideways and are cutting from top to bottom, be sure to turn it so the motor is on the left and the disk is on the right. this way the sparks dont fly towards you but away from you. if your do the same cut but are going straight into it with the grinder, then turn it the opposite way so the sparks fly downwards. i find wearing a long sleeve shirt with the gloves helps out too. you wont get little sparks flying onto your arm. hope that helps out.
Click to expand...

This is exactly what I was saying not to do in my last post. It is way, way safer to move the guard to control your spark stream. If you are cutting downward with the motor on the right side of the disc and the disc catches, the grinder will pull itself into the material. If the motor is on the left side of the disc, the grinder can kick backwards - straight into you. I met a guy in my 2nd year welding class that had a nasty scar from the bridge of his nose to the corner of his mouth from exactly what I've explained here (zip-cut went through his face shield and would've taken an eye except for his safety glasses underneath).

A simple way to remember is this: If the disc snags, it will move in the direction that is opposite to rotation or direction at the point of contact (just like your car tires). On one side of the disc, you're moving forward. On the other side, backward.

Not trying to be a prick, just don't want to see a "so I went to the hospital today" thread.

Have a good one, be safe, and have a cold one for a Canuck,

Nathan Dallyn
 
This is a very instructive thread. For me anyway..............

I'm a little out of it on some of this shop safety stuff because I took a looooong hiatus from working on metal but now I'm getting back into it and I don't wanna lose time because I did something boneheaded (that would be where I know better but get in a hurry) or just frikkin' ignorant (that's where I don't know better but give it a go anyway).

I appreciate my eyes, face and teeth a lot more as i get older to say nothing of hands and fingers.

Thanks gentlemen, I appreciate every single post in this thread.

Syn
 
You must log in or register to reply here.
Back
Top