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Why not expensive die grinders?

Stewie

Well Known Member
Hi all-
I just purchased a Sioux angle drill and love it already. I was thinking about tool quality, and was wondering why builders spend a fair bit on drills, rivet guns etc but I have not seen people recommend good quality die grinders in the "recommended tools" threads? Just curious - it's a tool that I use as much as, if not more than any other.
Eric
 
I have a Dotco dye grinder, it's one of my most used sheet metal tools and well worth the $$.
 
A die grinder is not a high precision tool, and doesn't need to be in order to perform its function well.

I use a $20 die grinder from Harbor Freight and it seems to do its job just fine.

In what way is a $400 die grinder so superior to a $20 one to be worth the price difference? Just curious.
 
Dynafiles are worth their weight in gold

A good die grinder is a must. Like a lot of tools, one that will last a lifetime is worth the cost. To me anyway.

The air tool I personally think is worth its weight in gold is a Dynafile (or equivalent brand). The model I have is: Dynabrade 40320. I was just using mine today, on some alligator jaws for upcoming tools for Hondajet. The unit accepts 1/4" - 3/4" belts.

I was telling a friend today how useful these are. You can change out belts, and switch quickly from sanding to polishing. It is readily throttleable, and you can really turn the belt slowly for great control. I like to hold mine so that the belt throws the debris away from me. This isn't a cheap air tool, but you will use it ALL THE TIME.

There are electric versions out there too. Dynafile is the gold standard.

http://www.aaabrasives.com/products/4401/D40320/dynabrade-40320---dynafile-ii-abrasive-belt-tool-5-hp-7-degree-offset-20000-rpm-front-exhaust-for-14-34-w-x-18-l-6-19-mm-x-457-mm-belts
 
Well, it has to be good enough to do the job

I have a good die grinder that I inherited from my brother Drex and when I need it it does the job perfectly - I used it last night to put a groove in the edge of a part for a perfect fit into a small space at the end of an installation. But, I don't use it often and when I'm done the part that I am working on is the important thing. If the tool allowed me to do the necessary work like this spinning variable speed manual tool has done that's all I care about. Tools like rivet guns and especially electrical pin and terminal crimpers predetermine the quality limit of the product and therefore demand more of my attention in tool selection.

Bob Axsom
 
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A good die grinder is a must. Like a lot of tools, one that will last a lifetime is worth the cost. To me anyway.

The air tool I personally think is worth its weight in gold is a Dynafile (or equivalent brand). The model I have is: Dynabrade 40320. I was just using mine today, on some alligator jaws for upcoming tools for Hondajet. The unit accepts 1/4" - 3/4" belts.

I was telling a friend today how useful these are. You can change out belts, and switch quickly from sanding to polishing. It is readily throttleable, and you can really turn the belt slowly for great control. I like to hold mine so that the belt throws the debris away from me. This isn't a cheap air tool, but you will use it ALL THE TIME.

Mark and I think alike...
I'm gonna have to keep an eye out for a Dynafile now :D
 
A die grinder is not a high precision tool, and doesn't need to be in order to perform its function well.

I use a $20 die grinder from Harbor Freight and it seems to do its job just fine.

In what way is a $400 die grinder so superior to a $20 one to be worth the price difference? Just curious.

I have an old (at least 30 years old) Dotco die-grinder. It's smaller and lighter than any of the cheaper tools out there. Even with it's worn out gear set it will run newer grinders into the ground.
 
die grinder?

I had to look up what a die grinder even was! I have never used one before I started my build. After the tail kit is nearly complete, I still haven't used one. I did buy a fake Dremell kit from Costco, but I haven't opened the box yet.

I do have a really cool tool that fits on my angle grinder with a couple of chains on it for carving wood, but I probably won't use it on the plane either! I will look at the posts and the links and see what the die grinder works well for. The one with the mini belt sander looks like it could have a bunch of uses.

That is one of the fun things about building, finding more tools.
 
Grinder

As a professional aircraft mechanic I would never spend more than $20 on a die grinder. I've had expensive ones and they work no better than a Habour Freight cheapee. They usually last about a year in an industrial environment. (I'm speaking of heavy check chasing lots of corrosion job).
Drills, ect I would go for the high quality stuff.
 
I got a Sioux

Hi Eric,

I just received my new Sioux die grinder in the mail. Dunno if it works well or not but it sure is nice to play with. :D I'll let you know.

Gerry.
 
I am a mold maker and machinist so I have a fair amount of tools. I have a Sioux Rivet gun and a Sioux Air drill. I love both of them and built my RV-9A over the last 8 years with them. I use cheap die grinders in my work because the expensive ones don't last that much longer than the less expensive ones. How much I use a tool every day is how I determine how high quality I buy. Even if a cheaper rivet gun would have done the job just fine I wanted a Sioux just because I liked how it felt in my hand and it is a pleasure to use. If that new Sioux grinder gives you a warm and fuzzy then it's worth whatever you paid for it. :)
 
My cheapo 90 degree die grinder was one of my most used tools, during the airplane construction. A lot of 2" twist on scotchbrite pads were attached to it. It still works, many years later.
 
Interesting set of responses. Since I use my die grinder so much, I actually have two of them (Home Depot cheapies) and one didn't last more than a few months before I needed to replace it, prompting this thread. I'm working full time on my -4, so well-balanced, low-vibe tools make the job more pleasant. As I've said on a different post, one of my favorite tools is a Rohm keyless chuck. Saves me a huge amount of time, and is obviously a very high quality item. Absolutely worth the money.
I do understand that compared to a drill or rivet gun, die grinders do "rough" work and so high precision is not really necessary. However, from a vibration/balance standpoint, as well as economical standpoint (how long a Sioux would last compared to a HD/HF cheapie), I wonder if it is worth the money. A Sioux die grinder is only $60, so I may buy one and like Gerry report back.
Thanks for all the input.
Eric
 
Sioux makes two grades of product, Sioux and Sioux Force. My understanding is that the Force line is imported. They are certainly cheaper.
I own Sioux, american made, drills and rivet guns, but my 90 deg angle die grinder is a Force.
I have hundreds of hours on it and it is still performing as new.
 
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