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bench grinder help
- Thread starter walldan
- Start date
Bill_H
Well Known Member
Well, I am a newbie compared to Bill R, but the bench grinder posed no problem using the mounted Scotchbrite wheel on my Rv12 build. What you use it for does not require any real torque. It is just very fast and convenient to hit the edges of the small parts.
You don't use another type of wheel that may already be on the grinder on the aluminum, perhaps that is the issue.
Ditto on removing the guards and rests.
You don't use another type of wheel that may already be on the grinder on the aluminum, perhaps that is the issue.
Ditto on removing the guards and rests.
BillL
Well Known Member
Yep - no grinder needed, at least for aluminum. A hard wheel will collect aluminum in the crevices, heat, expand, crack wheel and it will eventually explode.
I got the lowest price HF bench buffer and installed a hard, and medium scotchbrite wheel on the ends. A fantastic question from Bob Avery when I ordered - which wheel do I want? I was clearly clueless, so he suggested a softer wheel than standard Vans recommendation. I got both. 95% of the work is on the softer wheel.
What's the difference? Well, the 3M recommendation is to use the end of an old file to true the wheel after installation. The soft one was fine, the hard one CUT DOWN THE FILE!! It is that hard. I truly use it like a grinder on aluminum parts that need a little trimming.
I got the lowest price HF bench buffer and installed a hard, and medium scotchbrite wheel on the ends. A fantastic question from Bob Avery when I ordered - which wheel do I want? I was clearly clueless, so he suggested a softer wheel than standard Vans recommendation. I got both. 95% of the work is on the softer wheel.
What's the difference? Well, the 3M recommendation is to use the end of an old file to true the wheel after installation. The soft one was fine, the hard one CUT DOWN THE FILE!! It is that hard. I truly use it like a grinder on aluminum parts that need a little trimming.
Infidel
Well Known Member
You'll likely find it is a piece of junk and anytime you apply nominal pressure to remove material, the motor will bog down. Usually, these Chinese brands will rev up to rpm, but the horsepower doesn't have any *** behind it.
When it comes to a grinder, get a good one. You won't regret it.
Bench grinder abrasive
Mount one of these on your bench grinder. (And I think cheap grinders are OK unless you intend to put hundreds of hours on them)
These flap wheels are great for shaping aluminum. And putting them on a bench grinder makes quick work of any project. You can get others with a stem to mount in drills.
http://www.sparkyabrasives.com/Item--i-FW-UNMOUNTED
Jim
Mount one of these on your bench grinder. (And I think cheap grinders are OK unless you intend to put hundreds of hours on them)
These flap wheels are great for shaping aluminum. And putting them on a bench grinder makes quick work of any project. You can get others with a stem to mount in drills.
http://www.sparkyabrasives.com/Item--i-FW-UNMOUNTED
Jim
David Paule
Well Known Member
I don't own a grinder or one of those big Scotchbrite wheels and get along just fine. Don't see any reason for them, frankly.
But do get a long Vixen file - that's handy.
Dave
But do get a long Vixen file - that's handy.
Dave
I don't mean this as a put down personally, but that can be why some people take 800 hrs to build an RV-12 and some people take 1200 hrs.
Some processes, that If properly learned, can save a huge amount of time.
I can fully deburr a wing rib in less than 90 seconds, where other people take 10+ minutes. Multiply that times hundreds of parts and it adds up.
I do agree with the vixen file. That is the first tool I pick up when starting preparation on skin edges.
RFSchaller
Well Known Member
I don't recall using the grinder much, but I agree that having a large selection of tools can frequently turn a half hour job into a 5 minute one.
Are you deburring absolutely everywhere in that 90 seconds, Scott - e.g. in between all flange tabs? I see a wide variation in what people consider sufficient deburring - and obviously value your opinion. I have stopped being quite so anal with the deburring, but I'm still way closer to the 10 min mark than :90. I am just finishing up my wings and I'll keep quiet at the hour mark I'm at
. I'm not familiar w/ –12 ribs, but don't imagine they are that different from other models. If you are talking all edges (between tabs, lightening holes) and flange holes in :90, I'll pay you to see your technique+1 for the vixen on skins. Makes for quick work and nice results.
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Now we are getting to technicality's, but I expected someone to ask,
I can do a rib in 90 seconds if it is one that the burrs produced by the punching process are on the "outside". Ribs formed with the punch burrs to the inside take a bit longer.
Bill_H
Well Known Member
The original question was why the price difference. If you take them both apart you will see a big difference in the quality of tne machining and the tolerances. The more expensive one will most likely be better balanced. And some of the price difference is simply profit because the name brand one is also made in
China. A really good baldor grinder made in the USA is over $1000.
The cheap one will work for deburring etc. if you wanted to install a diamond wheel and accurately grind carbide forget it, but you probably don't. On the really cheap ones getting any abrasive wheel to run smoothly can sometimes be a challenge. That's the nature of HF type cheap tools.
China. A really good baldor grinder made in the USA is over $1000.
The cheap one will work for deburring etc. if you wanted to install a diamond wheel and accurately grind carbide forget it, but you probably don't. On the really cheap ones getting any abrasive wheel to run smoothly can sometimes be a challenge. That's the nature of HF type cheap tools.
maniago
Well Known Member
I always get a kick out of these deburring discussions (even though the OP is more interested benchgrinder cost).
For some, the act of deburring is a fun unto itself. For some its a motion that must be accomplished to get to something else. For Piper, Cessna, Beech etal of the 70's and earlier, it was an act never done.
*caveat: I debur w/a 3M7A wheel in a drill press 99% of the time.
An A&P friend said that he always thought it important to debur until he climbed into the tail of a Cessna and found all of the sharp edges. I wasted lots of time deburring my RV-12. In some cases, deburring might do more harm than good if the alcad coating is removed from adjacent surfaces. Burs should be removed where two parts meet to prevent one part from scratching the other one. It is nice to be able to work on the plane without getting cut by sharp edges. If a part is so highly stressed that it depends on deburring to prevent cracking, then that part needs to be redesigned. Has an airplane ever crashed because parts were not deburred? I do not know, just asking.
RFSchaller
Well Known Member
I used the little hand held deburring tools. One had a little swiveling blade and the other had a V notch. Both worked great. I used the thumb test to identify what needed deburring which worked in all but one situation where the burr sliver got me --- Ouch!
I use the HF buffer and the Scotchbrite wheel from Vans for smaller pieces. Then I read somewhere(probably here) about the 1inch Scotchbrite wheel and screw on arbor. Used in a HF right angle diegrinder it was great for those long skin edges, gets those bumps right off. Total cost from Cleaveland folks less than $10, grinder about $15. You need to hold near where you work, and work at an angle so you don't get a groove in the wheel. It does use a lot of air.
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