Capri Tools 1HP die grinder, your thoughts please?

[Stobal]

So I came across this set of die grinders from Capri Tools:

https://capritools.com/shop/1-0-hp-air-die-grinder-set/

• Powerful 1.0 HP motor
• 18,000 RPM of speed
• Ultra quiet with specially tuned muffler, only 79 dBA
• Low air consumption only 0.45 CFM at 90 PSI ****(in the graphics it says 4.1CFM)
• Ergonomic non slip soft grip handle
• Air inlet: 1/4 NPT
• 1.4″ industrial collet
• 2 Year Warranty

The specs seem too good to be true. It also has a positionable exhaust which seems like it could be useful in certain situations. I am happy with all of my Capri tools but other than the blow gun non of them are pneumatic tools so I am left wondering. Does anybody own this or have any experience with them? Could those specs really be even close to accurate as far as 1HP and 0.45 CFM at 90 PSI. (In the graphics it says 4.1 CFM but still unbelievable) What are your thoughts?

 

[908Jim]

I doubt the specs very much. Air motors are largely limited by physics at a certain point so I'm guessing the power rating is inflated or the assumed duty cycle is very low to get that average air consumption rating down into the 4cfm range.

For reference, my Sioux SGD7 series is pretty heavy duty grinder, rated at .7HP and it runs down a 20 cfm compressor with about 10 minutes of continuous use. SGD10 versions (1hp) are rated at 30+ cfm.

 

[vwpieces]

Probably can only achieve that rating in Reverse.

 

[u3b3rg33k]

Somewhere I thought I read you need 7HP of compressor for 1HP of tool.

 

[GeoBruin]

Air tools like die grinders are often rated based on an assumed duty cycle of something like 25%. Meaning within a given period of time, the tool will only be actually running for 25% of that time.

Here's a video I shot testing various air tools and comparing their measured air consumption with their advertised consumption.

 

[Stobal]

Air tools like die grinders are often rated based on an assumed duty cycle of something like 25%. Meaning within a given period of time, the tool will only be actually running for 25% of that time.

Here's a video I shot testing various air tools and comparing their measured air consumption with their advertised consumption.

That is interesting. It’s weird to post a cfm that only represents 15 seconds out of a minute. Is this just to be able to boost advertised specs or is it related to “best practice”. Am I only supposed to be holding the trigger for 15 seconds of every minute?

 

[GeoBruin]

That is interesting. It’s weird to post a cfm that only represents 15 seconds out of a minute. Is this just to be able to boost advertised specs or is it related to “best practice”. Am I only supposed to be holding the trigger for 15 seconds of every minute?

I'm sure someone, somewhere has some kind of "data" that supports that type of use case. Someone in another current thread speculated that those numbers where developed for industrial settings where you may have multiple users with tools running off of a big air distribution system and it was a way to indicate how much drain one additional tool would add to the system on average.

If I'm being honest, it's probably not very likely that I hold the trigger down on a die grinder for a solid minute. In fact the 25% duty cycle is probably a pretty good estimation of my usage. But in my opinion, it's stupid to assume that in the specs you publish. Just publish the actual instantaneous consumption and let the user decide what their use case will be.

 

[Wamsutta]

For reference, my Sioux SGD7 series is pretty heavy duty grinder, rated at .7HP and it runs down a 20 cfm compressor with about 10 minutes of continuous use.

That's not fair to Capri because you're talking about real air tool right there. My Sioux 1954HP will twist my arm every time I squeeze the trigger.

 

[strutaeng]

It looks like a good tool. Agreed about the CFM usage: seems low, but I'm sure that's how a lot of tools get rated.

I've got the cheap HF due grinder and my 8.1 CFM @ 100 psi old compressor can keep up if tool is used continuously. When I was grinding some welds for a large guardrail job I did in my house, I was pretty much using the die grinder 100% and compressor ran like 75% of the time...did that for like 6 hours. So maybe 4-6 CFM is more realistic.

I'm sure this tool is more efficient than my HF versión though. I do eventually plan to upgrade to something nicer.

Someone may say, oh, just get an electric die grinder. But the variable speed of pneumatic is very nice. After some use, you develop a eye-trigger-pressure coordination for grinding things down very efficiently. It's a really cool tool.

 

[Rinspeed]

Lol at $250, step away from the crackpipe.

 

[Wamsutta]

I think what I'd do is spend the $250 on one good die grinder instead of two halfway decent ones.

 

[Stobal]

I think what I'd do is spend the $250 on one good die grinder instead of two halfway decent ones.

Any suggestions on a 90 degree “good die grinder?”

 

[Wamsutta]

Any suggestions on a 90 degree “good die grinder?”

THIS ONE HERE

PDF

 

[Chris_Hamilton]

I have several true 1 hp and higher die grinders (Dotco, Sioux) and they are much bigger than the one pictured. They are nice when you need them but for many tasks I don't use them because they have so much torque. Every 1 hp and above one I have will torque twist in your hand when you first depress the handle. Like I said good for certain tasks but a good quality "regular" die grinder will do most every task someone needs it for.

 

[Wamsutta]

Aircat 6255

 

[ZRX61]

I think what I'd do is spend the $250 on one good die grinder instead of two halfway decent ones.

Well over a decade ago I bought some at Horrible Fright for about $7 each. Plan was to throw them in the trash where they wore out or broke.
I still have them.

 

[2ndGearRubber]

Well over a decade ago I bought some at Horrible Fright for about $7 each. Plan was to throw them in the trash where they wore out or broke.
I still have them.

They vibrate pretty bad, bog easy, and are air hungry for their output..... but damn if they don't meet the bare minimum requirements for less than I spend on lunch.

 

[LopezBart]

When I worked for FMC back in the 80s, the folks building the BFV next door used Aero tools. I was impressed by the 4-6" diameter 3/4" wide carbide milling cutter they used in something that looked like a circular saw. This was in the rework area, repairing welds that failed Xray. Several horsepower on air, apparently, big fat air hose and it would remove aluminum like nobodies business. Loud as can be, and dangerous, too.

 

[Steve_P]

They vibrate pretty bad, bog easy, and are air hungry for their output..... but damn if they don't meet the bare minimum requirements for less than I spend on lunch.

Yeah, I had several $9.99 HF die grinders I used for decades; I'm sure 50+ hours on one. Not a lot of power, bog easy, bearings were crunchy after years of use..... but still working. I replaced them with a snap on and a Dynabrade, both USA made, and they're so much nicer to use, and waaaaay more power. But each cost 15-20x as much as one HF.

 

[cvairwerks]

My Dotco 90 deg is from about 1970 production and still going strong. Dotco and Sioux pretty much rule in the production world. Can't comment on the Aircat. One thing about Dotco, is that should you need parts, almost every part for anything they made is available. I had to order a collet and nut for a straight grinder that was made in the 60's, and it was here in just a few days.

A bunch of years back, I did a test with the HF straights and right angle units. Of the 4 I bought of each style, all were replaced at least twice under warranty within 3 months of buying them. I think I tossed the last ones about 5 months later, as all were frozen up and had bearings there were coming apart.

 

[Wamsutta]

I have no experience with the Aircat. I just posted it because the picture is pretty.

 

[Rinspeed]

I have no experience with the Aircat. I just posted it because the picture is pretty.

I have a Aircat impact and it's been an awesome tool.

 

[Wamsutta]

I have a Aircat impact and it's been an awesome tool.

That Aircat die grinder has no lock off tigger I noticed. You go to grab it the wrong way and it'll light up in your hand.

 

[Rinspeed]

That Aircat die grinder has no lock off tigger I noticed. You go to grab it the wrong way and it'll light up in your hand.

I always cut those stupid locks off to tell you the truth.

 

[dnschmidt]

Air tools like die grinders are often rated based on an assumed duty cycle of something like 25%. Meaning within a given period of time, the tool will only be actually running for 25% of that time.

Here's a video I shot testing various air tools and comparing their measured air consumption with their advertised consumption.

I knew the air file would use the most air. If you cut the air hose the air file would still probably win that race. This is why I always say if you're going to buy an air compressor start at really big and considered huge. It's all ******** on these tool boxes when it comes to air demand. Typically, I multiply by four.

 

[Hohn]

THIS ONE HERE

PDF

VERY few users will ever benefit from the industrial durability of a tool like that. A good home gamer unit for half that can be found that is well balanced and has reasonable runout.
I've had great luck with the AIrcat stuff, but don't own any of their die grinders.


I have a cheap Chinese IR that will turn your hand numb with vibration. It's a miracle that it hasn't failed the output shaft bearing. Joke's on me-- it probably has no output shaft bearing and that's why it vibrates so badly.

 

[Hohn]

So I came across this set of die grinders from Capri Tools:

https://capritools.com/shop/1-0-hp-air-die-grinder-set/

• Powerful 1.0 HP motor
• 18,000 RPM of speed
• Ultra quiet with specially tuned muffler, only 79 dBA
• Low air consumption only 0.45 CFM at 90 PSI ****(in the graphics it says 4.1CFM)
• Ergonomic non slip soft grip handle
• Air inlet: 1/4 NPT
• 1.4″ industrial collet
• 2 Year Warranty

The specs seem too good to be true. It also has a positionable exhaust which seems like it could be useful in certain situations. I am happy with all of my Capri tools but other than the blow gun non of them are pneumatic tools so I am left wondering. Does anybody own this or have any experience with them? Could those specs really be even close to accurate as far as 1HP and 0.45 CFM at 90 PSI. (In the graphics it says 4.1 CFM but still unbelievable) What are your thoughts?

This is the same company that rates a compact 1/2" impact at 1700 lb ft.
Take a whole 40# bag of salt with their air tool ratings.

I'm a fan of their hand tools. But their marketing people are on drugs when it comes to the air tools.

Do you really need a full 1HP in a die grinder? My right angle die grinder wears a roloc all the time. But honestly for most of what I use it for, the small 4.5" angle grinder is a better solution. MUCH more control with the small air angle grinder because the disc is closer to the handle.
And so far, the both some to use about the same amount of air, which is to say, enough to bring my compressor to its knees pretty quickly.

 

[Stobal]

This is the same company that rates a compact 1/2" impact at 1700 lb ft.
Take a whole 40# bag of salt with their air tool ratings.

I'm a fan of their hand tools. But their marketing people are on drugs when it comes to the air tools.

Do you really need a full 1HP in a die grinder? My right angle die grinder wears a roloc all the time. But honestly for most of what I use it for, the small 4.5" angle grinder is a better solution. MUCH more control with the small air angle grinder because the disc is closer to the handle.
And so far, the both some to use about the same amount of air, which is to say, enough to bring my compressor to its knees pretty quickly.

One I definitely don’t need a 1HP die grinder. I am actually looking for something that has decent power but prioritizes air efficiency. That is why I was hesitant. Either it has more power than I need and ***** a lot more air than stated or if the air usage number is correct than it definitely won’t be 1HP which would be fine. I have a 5HP two stage and it runs a lot when I am grinding or stripping paint which is to be expected, but my cheapish die grinders tend to bog down and use a lot of air so I was hoping for something a bit better in both departments.

 

[Hohn]

One I definitely don’t need a 1HP die grinder. I am actually looking for something that has decent power but prioritizes air efficiency. That is why I was hesitant. Either it has more power than I need and ***** a lot more air than stated or if the air usage number is correct than it definitely won’t be 1HP which would be fine. I have a 5HP two stage and it runs a lot when I am grinding or stripping paint which is to be expected, but my cheapish die grinders tend to bog down and use a lot of air so I was hoping for something a bit better in both departments.

It's probably the case that if you bought a newer and reasonably well-made grinder (i.e. Taiwanese at least) then you could get reasonable air efficiency and power both.

I have the HF Chief full size extended inline d/g and I find it to be excellent overall and not much worse on air demand than my tiny little campbell hausfeld mini grinder even though it has significantly more torque.

Those Chief units are all Taiwanese, which means almost certainly somebody is rebadging the same tool. Heck, Capri is Taiwanese so it might even be the same as the Chief units!
Maybe the smaller Chief grinders?

 

[cvairwerks]

VERY few users will ever benefit from the industrial durability of a tool like that. A good home gamer unit for half that can be found that is well balanced and has reasonable runout.

Hohn: The nice thing about the industrial stuff is that it's designed to be used for long hours at a time. The ergonomics are often way better than lower priced stuff. I can run my Dotco's for hours and not have any vibration induced pain or numbing of my hands. The cheap ones, after about 5-10 minutes, I have to put them down and start doing hand flex exercises for a bit to counter the numbness and pain.

 

[Hohn]

Hohn: The nice thing about the industrial stuff is that it's designed to be used for long hours at a time. The ergonomics are often way better than lower priced stuff. I can run my Dotco's for hours and not have any vibration induced pain or numbing of my hands. The cheap ones, after about 5-10 minutes, I have to put them down and start doing hand flex exercises for a bit to counter the numbness and pain.

I won't argue that-- they are superior in a number of ways. I don't think that's at issue. The question is what it's worth, which is where the mileage varies.

 

[LXCam]

I bought a few each (90 n str) of these offerings a few years back because there was some smoking deal posted here. I’ve been very happy with them.

St. Louis Pneumatic

 

[2oolhound]

I can run my Dotco's for hours and not have any vibration induced pain or numbing of my hands. The cheap ones, after about 5-10 minutes, I have to put them down and start doing hand flex exercises for a bit to counter the numbness and pain.

This should probably go in the chainsaw thread but your post reminded me of "White Finger" we used to get from running chainsaws. Your fingers and hands would get pins & needles 1st, then go numb and finally turn white. We had to swing our arms in circles for several minutes to try to get blood in our hands but that didn't work either. I was young and dumb and learned to hold the saw in different ways to just keep working. I was sure my hands would be ruined for life eventually but now in hind sight I quit getting white finger soon after I quit falling timber and have zero issue with it now in old age decades later.

 

[Steve_P]

I knew the air file would use the most air. If you cut the air hose the air file would still probably win that race. This is why I always say if you're going to buy an air compressor start at really big and considered huge. It's all ******** on these tool boxes when it comes to air demand. Typically, I multiply by four.

I'm not saying they're the only one, and I'm not saying they're 100% honest, but Dynabrade does not do this BS fantasy underrating nonsense that most do. 28 CFM is the spec for this random air file that I pulled up

Dynabrade | Made in USA Abrasive Power Tools & Surface Finishing Solutions

Portable power tools supplier — Boost your operators' productivity with durable portable pneumatic abrasive power tools. Precision tools for all your industrial grinding, cutting and polishing productions. Long-lasting solutions

www17.dynabrade.com

edit:
23 CFM for a 0.4 HP die grinder

Dynabrade | Made in USA Abrasive Power Tools & Surface Finishing Solutions

Portable power tools supplier — Boost your operators' productivity with durable portable pneumatic abrasive power tools. Precision tools for all your industrial grinding, cutting and polishing productions. Long-lasting solutions

www17.dynabrade.com

 

[Hohn]

I'm not saying they're the only one, and I'm not saying they're 100% honest, but Dynabrade does not do this BS fantasy underrating nonsense that most do. 28 CFM is the spec for this random air file that I pulled up

Dynabrade | Made in USA Abrasive Power Tools & Surface Finishing Solutions

Portable power tools supplier — Boost your operators' productivity with durable portable pneumatic abrasive power tools. Precision tools for all your industrial grinding, cutting and polishing productions. Long-lasting solutions

www17.dynabrade.com

edit:
23 CFM for a 0.4 HP die grinder

Dynabrade | Made in USA Abrasive Power Tools & Surface Finishing Solutions

Portable power tools supplier — Boost your operators' productivity with durable portable pneumatic abrasive power tools. Precision tools for all your industrial grinding, cutting and polishing productions. Long-lasting solutions

www17.dynabrade.com

I noticed the Sioux uses SCFM also. When Sioux shows their 1hp die grinder at 30 SCFM and some other guy is rating his tool at 4 CFM, I know which one *I* trust.

I actually called Aircat and had a bit of a discussion with an engineer there. He was very gracious in giving time but unfortunately the discussion was head-bangingly frustrating.

He couldn't or wouldn't tell me precisely how Aircat gets a die grinder to show 4 CFM or such. He did suggest that the derate was *entirely* duty cycle because while 25% cycle cycle is very common it is NOT always a 25% duty cycle rating. He basically said that they make up an expected duty cycle and rate it at that.

So unless you buy an industrial tool that is assumed to be 100% D/C and rated in SCFM (Sioux, dynabrade, etc) your consumer grade air tool ratings are essentially pixie dust based on some duty cycle that may or may not be 25% but commonly is.

When I asked him why they don't use SCFM ratings, he reply was basically "I could never sell a tool because customers will see the high air demand and think they can't use a 20SCFM tool with a 5SCFM compressor."

In other words, customers are dumb and we have abandoned any responsibility to educate them on how tanks and duty cycles work.

Which I reject out of hand. I hate that attitude. Just how many air tools are purchased by people who know nothing about air systems? Your typical shop has people who know that die grinders use a lot of air and they already know your 4 CFM is pure BS.

Large businesses doing big air tool buys are hiring consultants and experts who know how to account for duty cycle. SO your BS derate does nothing but frustrate them and you'll have to cough up the real SCFM ratings anyway. Same for any DoD or .gov contracts.

So what Aircat and others are saying is that they are so concerned about the stupid 10% of potential customers that they will annoy and frustrate the 90% of customers who can do 3rd grade math and account for duty cycle in SCFM ratings.

I give that attitude 0/10 do not recommend.

 

[Hohn]

My Dotco 90 deg is from about 1970 production and still going strong. Dotco and Sioux pretty much rule in the production world. Can't comment on the Aircat. One thing about Dotco, is that should you need parts, almost every part for anything they made is available. I had to order a collet and nut for a straight grinder that was made in the 60's, and it was here in just a few days.

A bunch of years back, I did a test with the HF straights and right angle units. Of the 4 I bought of each style, all were replaced at least twice under warranty within 3 months of buying them. I think I tossed the last ones about 5 months later, as all were frozen up and had bearings there were coming apart.

That Dotco anecdote about getting parts for something made in the 60s is pretty awesome. If only everything was so well supported!

You think we can talk Dotco into making refrigerators or other household appliances since they're almost all **** now?