SteelMike

SteelMike

Well Known Member
Hey guys,

I'm just now realizing you can spend a bundle of money on a torque wrench, so I just thought I would shoot this out there to see if I can get some recommendations. I wouldn't want to spend all that money and get the wrong thing! Looking for something mid-market, not cheapo, not super expensive.

Many thanks - in advance,

mike
 
If you are looking at high end tools, check out CDI torque wrenches. CDI is a Snap-on company with more moderate pricing.
I have two and am very pleased.

Randy Hooper
 
I bought one from sears... $100 IIRC. works fine for now. I'm sure I'll need more than one eventually.
 
danielhv said:
I bought one from sears... $100 IIRC. works fine for now. I'm sure I'll need more than one eventually.
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Based on my experience, "for now" is the operative phrase. The Craftsman "click" torque wrench I purchased a few years ago did not hold up well. I replaced it with a CDI. And no, I'm not one of those guys who can tear up an anvil with a rubber mallet. :p My 1/2" drive Proto torque wrench from the late sixties is still doing fine. $50 extra can buy you a lot of extra quality here. The CDI wrenches are very nice and are a good value in a quality tool.
 
In general, yes, you need a beam or dial type torque wrench calibrated in inch pounds and able to read in a very low range.

See AC 43.13, page 7-6, para 7-40c. It basically says, to torque properly, you first have to measure the drag of the nut, e.g., when you use one of those nuts with the plastic inserts, you might get 10 lbs or more before the nut bottoms out. And it varies, from nut to nut,. so you can't just use some arbitrary number. So, with a beam type wrench, you measure what the drag is, then add that to the spec and torque to the sum of the 2 numbers. I like the clicker type wrenches, but you can't measure the drag with a clicker.

And the rule of thumb is to torque the nut, not the bolt.

Bicycle tool suppliers sell a beam type torque wrench that reads low numbers. Find them on Ebay, search for Park TW-1; they generally run about $35 and measure 0-60 inch pounds.

What, you don't have a copy of AC 43.13? It's the FAA bible on acceptable practices. Get one from Van's, who has them for a decent price. Has all the info you need and then some.

OTOH, there are several places where you can't use a torque wrench--torquing the nuts on the bolts that hold the landing gear weldments to the center section for example. No room in the center section for a socket.
 
By the way, when you say CDI, do you mean the $319 one (at aircraft spruce)? Just want to make sure we're talking about the same thing - I just can't see spending three hundred bucks on a wrench.
 
craftsman torque wrenches work fine if carefully handled. they fail in numerous ways however. the plastic handle breaks, the platic lock breaks, the internals fall apart when dialed below the lowest setting and the locks fail easily. ive worked at sears for 5 years and their cheap ones are just that. their good ones are a little better. buy a good one (not sears) and have it forever. IMHO you may need more than one. you need a 0-100 in lbs, and a 10-150 ft lbs. maybe even a 0-70 dial indicating for your flight controls. torque wrenches are not very accuarate at the low end of their range, and the click is almost unnoticed.
good luck, buy which ever you can afford and be carefull with it, and it will do the job just fine.
 
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FYI - I tried to order one of the 20-150 inlb torque wrenches from toolsource... they are backordered until late Aug at the earliest.

Anyone know of any other vendors with similar pricing?
 
I haven't had any problem with my Craftsman clicker. However, 250 in/lbs is not enough; you will want something with a larger range. Fortunately, I had a beam torque wrench that goes up to 120 ft/lb. There's a lot of fasteners FWF that will require it. The spark inserts for my Lightspeed are 25 ft/lb which is just over the range of the clicker at 274 in/lb. Then there's the prop bolts at 60-70 ft/lbs, not to mention some of the engine bolts. That said, you can wait until you get to the FWF before getting a high-range torque wrench; I don't recall anything in the airframe torqued nearly that high.

Also, if you've never used a torque wrench before, get someone to show you how. It's not hard but there are a couple of tricks and it helps to see them in action.
 
Torque Wrench

Hello All
Any yes any threaded fastener can be torqued. My torque wrenches run trom the ity bity inch ounce to the gonzo beater foot pound models. I have built many torque wrench calibrators. When some body says they can't torque a nut I say bullxxxx. They say that only because they can't get thier super duper torque wrench to fit. What torqueing does it stretchs a tempered metal fastener a specific amount to get a proper clamping force. Now let us take a real problem of torqueing a base bolt. Let's say that we need 169 foot pounds. Digging in your tool box you find a box end wrenche that measures 6.91 inches center to center. This wrenche is 58% of one foot. 169 pounds times 1 plus 58% equals 267 pounds. So you will have to pull 267 pounds on the wrench to equal 169 foot pounds. So get your big en fish scale and pull until you see 267 pounds. Easy isn't it. Friction makes a problem so make sure every thing is clean and lightly oiled.
 
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Lee, are you sure about your calculation? I would think the pull value would be simply (169 X 12) / 6.91 which equals 293 rather than 267. Perhaps I'm missing something or don't understand the scenario.
 
SteelMike said:
By the way, when you say CDI, do you mean the $319 one (at aircraft spruce)? Just want to make sure we're talking about the same thing - I just can't see spending three hundred bucks on a wrench.
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Definitely not :eek: - don't recall the exact price, but it sure seemed way less than that. I got it from a company that markets precision measurment tools to race car engine builders. Can't recall the name right now, but I can find it when I get home. I'll also get the model number of the wrench. I also have a "torque screwdriver" that I really like for the AN3 and other really small fasteners.
AND, in the interest of full disclosure, I actually do still have a Craftsman torque wrench that has lasted well. It's a bending beam wrench that I bought when I was 14 :D. Not much to go wrong with that baby, and I successfully hot-rodded two cars with it, but these days it's all click all the time!
 
Shhhh!

TSwezey said:
That's the only torgue wrench you will need!
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Hey! Don't let my wife hear you say that!! She fully understands that torque wrenches are built like scissors, and you need both left and right handed models!
 
I picked up a Proto dial torque wrench (0-600 in-lb) for about $100 on eBay, brand new. It's done me well so far, and is a great wrench. You should easily be able to find one for under $150.
 
Careful about oiling before torquing. Some torques are given dry. The Hartzell prop manual specifically states that the mounting area and bolts must be clean and dry.
 
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