Over at Amazon, they recently listed new Dewalt rotary rasps.
While rotary files and rasps designed to be chucked into a drill or rotary tool aren’t unusual, these stood out to me.
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Features include a 1/4″ hex shank and precision cutting edges that are said to reduce clogging or loading.
They’re said to be used on ferrous metal, for deburring, shaping, and grooving applications.
There seems to be 2 styles – conical (DWA4971) and cylindrical (DWA4971)
Price: ~$10 each
Buy Now(Conical Rasp via Amazon)
Buy Now(Cylindrical Rasp via Amazon)
I’ve seen similar burrs for use on wood and other similarly soft materials. I’ve seen plenty for use on metal and ferrous metal materials, but rotary rasps? I think these are the first I’ve seen for use on such materials.
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Have you used something like these rotary rasps in the past? Would you use these for any of your typical types of work?
fred
Priced at almost $10 on Amazon – you can buy them at Lowes for $4. This is getting to be rather typical of Amazon pricing – where they build in shipping costs into the price. They would be more consumer friendly if they stated the shipping price separately and calculated a different shipping rate if you bought more than one item. As it is – if you bought 1 of these – you would be paying for the shipping ten times over. There are many things I like about Amazon, this is not one of them.
fred
I should have said “if you bought 10 of these”
Adam
I’ve been buying a lot of Wall Control pegboard and hooks for work, and they do the same thing there. Many of the accessories are $10-15 cheaper ordered direct from Wall Control. No free shipping, but it still ends up being the same cost or a bit less.
fred
Yes – I realize that most folks realize that there is no such thing as “free shipping”. The cost is real so it must be somehow built into the price. Getting you to buy more – spreads the cost out a bit – so some online retailers have a minimum purchase for them to waive adding on a shipping cost. They may be reducing their profit margin a bit – but they are getting you to buy more. This is akin to them offering you a quantity discount.
Sometimes an Amazon (eBay et. al) third-party vendor will list the a price at something like $2.95 plus $5.95 shipping – seemingly a terrible deal. But if you buy ten – the price might be $29.50 plus the same $5.95 shipping – perhaps a better deal.
Koko the Talking Ape
I am having trouble visualizing how these would work on iron or steel. It seems like the ball-end rasp in particular would just make a set of shallow grooves in the metal. Are we sure they aren’t mislabeled or something?
Hilton
I bought similar rasps about eleven years ago to try and enlarge holes I had drilled in some square tubing as I didn’t have a big enough drill bit. It was a disaster and I still haven’t finished the project.
Jimmie
Likewise. I tried using a rasp like this to slightly enlarge the hole in a dead-bolt striker plate. Things couldn’t have gone more wrongly. The metal quickly clogged the rasp rendering it useless. Wound up having to file down the opening manually. Maybe this was a case of using the wrong tool for the job.
Nate
Sure look like wood rasps to me. Typically i would use carbide burrs for what they are claiming this does.
fred
I looked at the package at Lowes this morning. There is no verbiage – just 3 little icons on the right side.
Under “For” they show (top to bottom) : a depiction of a cordless impact driver; a depiction of a cordless drill; a depiction of an “I-Beam; a depiction of what looks like a wood 4×4; a depiction of some pipe – with the letters PVC; 1/4” and a hexagon with the word “shank”. All that on the back are warnings about wearing eye protection – written in English, Spanish and French.
JoeM
Want. Don’t care. Want. I’m an idiot and I want these.
Noah
I just can’t see them lasting long.
fred
I think that after some use – they will confirm Count Rumford’s observation that a dull boring tool will produce lots of heat and not much else.
T
Lol. I know alot of dull boring tools that dont produce much.
JoeM
If you use them with a light touch, letting the speed of the rotation do the work, (Like you do with a Dremel tool) then I can see these working pretty well, and lasting quite a long time.
I think we often get confused when we see the rotary version of a hand tool. The Hand Tool, without a doubt, needs some force applied to do the job, especially rasps and files. But when we’re talking a spinning version, on a power tool spinning faster than our hands could ever spin the thing, even if we were on some sort of steroid/methamphetamine combo, then the barbs don’t need force to work. They really just need to be rested in place, with a tight grip on the tool so it doesn’t fall out of your hand while spinning. It’s counter-intuitive, but the harder the material with a rotary device, the more gentle you need to be. As such, you could set the drill or impact driver to their highest speeds when using metal, and just barely touch the hole you’re widening, then just wait while it does the work. You could do the same in hardwoods like oak, and use the slower speeds for softwoods like pine or cedar.
I’ve been using Dremel rotary tools since I was 9, and broken or dulled more than my fair share of rotary bits and discs because I was always impatient and pushing on them too hard. I learned the rule of speed over torque for these things. Dremel rotary tools don’t have a lot of torque at all, they have immense speed instead. The same can be said for the much slower drills and drivers we use every day. They’re able to spin things significantly faster than we can move them. So it makes sense that rotary versions of heavy-force tools, like rasps and saws, need a much lighter touch to let them do the work with speed over force.
I like these rasps. For those times when I just don’t want to file and rasp my way through a project, these can strip a bunch of material away, so I can get on with the rest of the project.
And… Just to resolve the issue with Amazon… Typically Amazon sucks when it comes to tools and their prices. If you can find a smaller online-only tool place, they’ll have better pricing, and better deals on shipping. Unless you want some cheap pair of tweezers, or you just need a cheap power plug of some sort… Amazon doesn’t typically offer much of a benefit to anyone in the Tool sector. They may have wider selection, or the odd deal, but they’re meant more for other, smaller stuff. Books, DVDs/BluRays, Etc.
Hilton
Thank Joem, I will try your rotary method next time, good instruction there so thanks again.
With regards to Amazon, I would not otherwise be able to source all types of tools, spares, consumables, jig etc without the big giant. I live in South Africa and a lot of other US stores are xenophobic so the majority of my purchases are either Lee Valley or Amazon. Sad but true.
JoeM
Well… South Africa… Honestly, you have to ignore my advice about Amazon when you’re in an entirely different part of the world like that… A lot of these big companies are North America and Europe Centric. I’m from Canada, where Lee Valley is I might add, so I have some pretty good options, like BlackRock Tools online… But you? You gotta go looking and find whatever you can locally. I’m not sure if you fit into the jurisdiction, but the Middle Eastern or Indian/Asian divisions may treat you better than Amazon does. I genuinely don’t know. South Africa is REALLY difficult to source things for globally.
As to Rotary Tools… Trust me, we all screw up sometimes. We all have that logic with power tools, push harder=job go faster. With a full sized Drill or Saw, that’s totally true, as long as you don’t exceed the capabilities or durability of the drill or saw. But tiny, spinning discs, sanding, or polishing stones, sharpening edges, and rasps like these ones? You just have to be gentle. A light touch will do the job.
I’m POSITIVE that the ones these look like, as Koko here is pointing me to, are not meant for metal. I’m pretty sure these aren’t either… to a point… I think these can clean up flashing, or remove sharp edges, or generally do surface work. DOUBLING the size of a hole? No. Cleaning the edge of a hole, so maybe the fastener can be closer to flush? Probably.
But, then again… I’m not sure anyone sane really and truly WANTS to use a rasp on metal. A FILE, maybe, but not a Rasp. Files can sharpen blades at least, but Rasps rough up the surface, and remove mass unevenly. You’d want these for taking flashing off a metal casting or a plastic or fiberglass molding, or to rough up the surface of some wood. This is a very niche kind of tool, and I can totally see where others would hesitate to see the value. I don’t see a wide market for them either, but I do see what they’re intended for.
I’D use these. But, really only for those times when I need to prep a wood surface for reshaping/hiding where I’ve joined more than one piece together with glue and prayers. I only see them as wood and plastic tools, and can only speculate at what you guys see them for with metal.
Vincent
Hi Hilton, from South Africa myself. Have you tried to buy your tools locally through the likes of CIB Partners (DeWalt dealers in South Africa)? I’m sure they will, eventually, keep most of the DeWalt range as the need / want arrises within our market. There are sooooo many brilliant things DeWalt / Stanley / Black+Decker / Ryobi / (That article on their garage door opener with accessories, I was drooling.. LOL) Milwaukee offers internationally that we simply can’t buy locally. I tried buying some stuff off of Amazon, haven’t had much success to be honest. Hope you come right! And ALMOST happy spring!
Koko the Talking Ape
Speed over torque, sure. But that isn’t the issue people are pointing out. People are pointing out that the teeth don’t seem to be designed for iron or steel. They seem to be designed for wood, fiberglass, plastic, or other soft materials. They look very similar to these, which are “not for use on ceramics, metal, or stone.”
http://www.highlandwoodworking.com/auriou-rotary-rasp-6mm-shank.aspx
For ferrous metals like iron or steel, I would expect the rasps to be made of something substantially harder than iron or steel, like carborundum or silicon carbide.
JoeM
No no… Those are definitely not the same as these DeWALT ones, but I don’t think these DeWALT ones are meant for doing a lot in Metal or Ceramic either. I think, at best, they’re for removing flashing from castings or moldings.
Lee Valley has or has had some similar ones that called the Typhoon Carving Burrs by Foredom. In fact there’s a whole section of Lee Valley devoted to far better solutions for carving in various materials, and they are not limited to Rasps.
http://www.leevalley.com/en/wood/page.aspx?cat=1,130&p=43409
The Typhoons specifically are probably a lot better than those Auriou ones, especially since they’re Tungsten Carbide. Not going to do any better in metal, but they’ll probably last longer than the Auriou ones.
Here: http://www.leevalley.com/en/wood/page.aspx?p=69808&cat=1,130,43409
I admit though… they appear to be significantly more expensive… though I may be biased as a Canadian, looking at the site in Canadian dollars… My Math is probably off by a lot.
Mau
I’m not seeing much use of these rasps on metals, even on Al. We use a lot the rotary files, but we never used rasps (even the manual ones). Probably they’re only mislabeled.