I know that many people here are complaining about the aluminium as testing material but helicoils/thread inserts are most commonly used for aluminium to repair stripped threads or to reinforce existing threads if you need to repair a thread with an insert in steel it is most likely that the insert will also be stronger or at least as strong as the steel. I recently fixed my oil drain plug with a helicoil cut the thread, install the insert, insert the bolt and tighten according to factory spec.
Thank you for the video. Probably one of the best non-biased comparisons on the internet. Anytime Helicoils are brought up, Timeserts are always thrown up as a better solution. There are also videos of people talking about how timeserts are better but they are extremely biased as they sell the timesert kits. Looking at both from an engineering standpoint the biggest pro for a timesert would be the flange (to keep it from running deeper) and the more positive locking feature (swaging the end threads during insertion). A lot of people keep saying that the con to the Helicoils is that it's just a coiled wire, when in fact this is actually the advantage. Each loop/thread can move independently vs solid insert. This allows more even force on more threads. On a solid insert or bolt, the first 2 threads see 75% of the pull force. WIth a helicoil 80% of the force is spread over the first 4 coils. No bolt is perfectly nominal and neither are taps, and the helicoil can adapt to this better since it isn't as static. Plus since it's just a wire, better materials can be used to manufacture them more easily.
Thanks! Your testing technique was WAY superior to anything I could have ever done. After watching, now I have the confidence to use a helicoil to repair the threads in a brake caliper. Most of the load is sideways to the helicoil, not towards pulling out. I will monitor the repair for a while for any evidence of failure. Damn threaded aluminum ....
Hey Kevin, Nice testing video. I thought it was odd that the feeler always releases from the left side first. I think you may have some geometry error in the press setup that is loading the assemble off center slightly. Also technically just because the feeler comes out does not mean anything has yielded yet. The fact you have so much head room over the feeler coming out would be consistent with elastic stretching when the feeler comes out. The failures are pretty cool to watch. Fasteners typically fail when they are being torqued as opposed to pure tension loading. The shear stress is highest when trying to rotate the fastener when torquing. Fun video! All the best, Tom
Thanks, Tom! I, too, thought it was odd that the left feeler gauge came out first. The cause has been puzzling me since I did the tests. Maybe I'll put it in backwards and try one again to see if the press is flexing or if it's a geometry issue with my rig. I stole your use of shim stock after watching the test you did. I guess it's a good thing I used one on each side. The broken bolt caught me by surprise. When doing the other tests I was standing behind the mill table. After they all pulled out I decided to grab another chunk of aluminum and stuff a BigSert in it. Then, I stood beside the camera when torquing the bolt. Scratch one camera battery cover! That's what complacency gets you. Kevin
@@RidgewoodMachine I have to think it's because the faces of the blocks are not machined perfectly and the aluminum blocks are giving against each other. Perhaps matching all contact faces and using steel parallels between blocks will remove the aluminum as a variable. All the aluminum faces have to be machined. Tolerance? maybe .003? This would obviously be a time-consuming exercise, as well as possibly damaging 2 sets of parallels. maybe not. Obviously, you have to check for left-right problems with the press itself.
I agree. Helicoils are perfectly adequate, and perhaps better in some aplications, regardless if there is something better, they work well in anything i have used them in so far.
An objective, well thought out and executed test video on RU-vid, and with a control no less. I believe that's a first. Thank you, Kevin! By the way, I just think the left feeler was out of spec (or the right one) not your setup... ;-)
Good testing liked it. I have removed several of those other types that had failed and install Heli-coil. Always liked Heli-Coil and have rarely seen them fail. Thanks for sharing.
What a great demo, this is so nice to see. Ultimately the base metal is the weak point, which puts a limit on any design. Helicoil did pretty well! The TimeSert did not come through with the distinct advantage we all assume and talk about. I wonder how these would perform after a few years of corrosion and galvanic reactions.
I'm impressed. You clearly spent a lot of time, effort and money to give this information to the public. How can anyone give a hand down - I don't know and don't understand. School teachers and technical university professors should pay you part of their money because you clearly teach more of "important stuff" in half an hour than they in a whole semester. Thank you.
Despite torquing only to spec, I managed to strip some threads where my car's exhaust manifold mounts. This actually seems consistent with the control testing in this video. I'd like to repair this properly, and had purchased some helicoils. I was debating whether I'd rather use Timeserts instead since the install seems cleaner IMO. I was also debating whether I should also do the threads that are not stripped to add strength. This seems to be the only real side-by-side. And I'm incredibly grateful it exists! What's more, it properly includes a control! From this I've decided to stick with helicoil (I'd consider big-sert if they came in stainless. Maybe I'll look around) and will indeed to all bolt holes. Thank you so much for putting this video together!
Even thought Time Serts show as weak in testing, I prefer them for through holes. I install them from the backside so the bolt would be trying to pull the fatter part through the counterbore. Would be interesting to see that tested.
Interesting test. The basic Helicoil held up pretty good. sometimes low tech is better that high tech, when you factor cost and application. Thanks, you put some time into setting up this up.
Thanks for a very informative video , this is the kind of stuff I often think about but have no idea how to investigate it , you have taken care of that !
Excellent video. Thanks for all the work and time. Need to make a repair and, not having a lot of experience, this is exactly the kind of 'shootout' I was looking for. Technically you'd need multiple samples and a measurement systems analysis to know if your rig is truly repeatable but for any arm chair mechanic I'm sure this is far more scientific than the "hold my beer' crowd really needs. Well done!
I greatly appreciate this video and was surprised to see how well the Helicoil stood up to its fancier competitors. I had trouble understanding the squish test. I would have been easier (to follow) had you backed off the camera at the beginning to show the entire set up instead going into close up mode right away. I hope you don't mind me saying so. Overall very good video and extremely helpful in making the right choice for those of us who aren't set up to do these types of tests. Thanks.
Eric Mowrey thanks for the feedback. This was the first video of its type I have made and it shows. One of these I'll get better at this kind of thing.
I've tried the Heli-Coil's and TimeSerts in Corvair spark plug threads - Helicoil's a bit more work on an installed head but far superior!! Thanks for the test.
Great video, you should be a tester for Consumer Reports, I've known several, testing bores the hell out of me but real world application is always the best or makes you wonder how the hell it's working so well. Don't stop.
At home i use helicoil. At work i use the generic brand helicoil knock of. I need to purchase another set for a size i need and do not have, i was considering time sert. But after watching this i can only see one advantage that people talk about is they are better for something that is frequently disassembled. But i need it for an aluminum block small engine, it should be 30 years before i need to tear it down again if ever so ill just go with helicoil again because so far they have never let me down.
Thank you for your testing. Did I miss the point in the video where you showed how you are pulling the bolt out with a press? How are you changing the push into a pull?
I guess I didn't cover that too well. The big rectangular frame (13:37) is narrow enough to fall between the press load surfaces. The test bolt holds the aluminum to the bottom of the rectangular frame. Up close to the camera is a riser running across the press table and it has a partner in the back. On each side are the 1.75" x 3" blocks that support the aluminum. That means all 110 pounds of the fixture are hanging off that little bolt. When I press on the top of the rig that little bolt is the only thing resisting the force.
In this part of the world mechanists use a brass tube/pipe and using die make an outside thread on it. Then they drill the hole of slipped thread bigger and chamfer end and use moose to create inner threads in it. Then apply some two part locking compound insert the bushing and then create inner threads of the size of the bolt. These have never failed and are very strong. Can you also try it and run it through similar test? As I have never seen any thing about this in the mainstream media. Appreciate the video and subscribed
excellent Deathmatch! Have a striped out AL oil pan drain that need to be repaired and the timesert seems to be what most use. Great Job interesting to see the destruction.
I used a Helicoil to repair a stripped bolt hole for a mount on aluminum Honda transmission. As expected, everyone on the Honda forum I was on was like "It might work but timesert is better blah blah blah". I was able to reach full torque on the bolt (28 lb-ft) and I've been running the helicoil repaired hole for years without issue. The transmission mounts use very stiff rubber and a lot of vibration gets transferred into the chassis. Couldn't be happier w the helicoil
Seems like the Bigsert isn't an apples to apples since of course it has more circumfrence contact. I'm surprised the Helicoil did better than the Timesert which was recommended to me for a repair I need to do. I think I may just use Helicoil on my job.
It's wild how just a lil diameter makes this much difference. This month I did m10x1.5 timeserts in my M54, they're on an angle spec but the wrench said final torque was >70ftlb. One of them pulled but it was my fault for doing a crap job on it. You ran your tap by machine, right? I got myself into all kinds of trouble trying to hand drive that tap, even with that sloppy lil guide sleeve they sell...
Thanks for a great video! It would have been good to repeat the experiments a few times with each repair method to check for variation, but at least there were two related tests for each condition. I was not impressed with the BigSert -- if you make the hole much bigger it is not surprising at all that the joint is stronger. Often that is not an option due to space constraints. The Helicoil repair clearly was best among the holes of a similar size. While a solid bushing seems like it would make a strong repair. the wall of the bushing reduces the amount of possible external thread due to its thickness.
The whole point of the Bigsert is for repairing threads that have already been repaired once before, so a standard insert will not work, I wouldn't use one unless the previous repair had failed, or some muppet has tried drilling a busted bolt and gone off centre and made a total mess of it.
Thank you! I think I'm going to try helicoil I just need to repair a stripped thread on a valve cover ~10ftlbs. Didn't how strong each one was or know which to use.
I first became aware of Timeserts in the late 90's when the Cadillac Northstars were coming apart with pulled bolts and corrosion. General Motors specified Timeserts for Northstar block repairs. I never heard why HeliCoils weren't recommended, but maybe there was Corporate interest in promoting Timeserts? Up until then, Helicoils were all I knew, especially in racing.
Do you have a theory as to why timeserts were worse than helicoils? As far as I’ve searched, timeserts are praised more but obviously they held less in your test. I’m looking to beef up my 10mm head bolt/stud threads in my aluminium block engine, so I’m looking for the best option.
My opinion is the cast metal of the Timesert is not as robust as the wire used for Helicoils. Every Timesert failure showed the insert being destroyed where the other brands either stretched or pulled out intact.
@codenamecordon Did you end up going with Timeserts? If so, did the hold up over time? I’m looking to do the same upgrade so I’m extremely curious to know how it went!
I wonder what would happen if you install the Time-Sert in a through hole but do the pull test from the opposite side , I seen a comment & someone mentioned to do the same thing but with Heli-coils
Nice demonstration, but most oil pan drain plugs torque at about (22 ft-lb). Still interesting to see how much aluminum can handle. Most people don't use a torque wrench and over tighten most of the time, which damages the inner threads of said oil pan over time or at the time depending on how over tightened it is/was.
Whatever sert you put in, eventually it is still the aluminium thread that is holding it. Once the outer thread (aluminium) it is dstroyed, the sert just have nothing to hold on to. But if you were to be able to increase the thickness of the sert or even glued the sert with JB weld, the stress will be transferred to the bolt and having the smaller diameter it will just break. This is pure physic as the force has to go somewhere.
Excellent Video Kevin, I have often wondered at which is better and have favored a threaded insert over a helicoil simply because the coil is not solid an I suspect that the grip might not be as good as threading a sleeve such as a bigsert style replacement thread . We all have to remember that alloy is inherently soft and has limitations, but in general a Helicoil if employed properly is very reliable , depending on the location and usage, especially if there is no room to cut a larger thread and use a steel insert. I myself favor a steel threaded insert if there is room for the appropriate thread to be cut so that can be done , but helicoil's work , it's that simple.
These inserts are designed to repair or reinforce thee existing threads, i daught they actually see those maximum loads in real life. In aerospace i used the heli coil quite often to reinforce the threads in the 7075 T6 to reduce the wear and tear of the aluminum threads. Good video tho. 👍
In 40 years of machining parts for all major industries, DOD, NASA, satellites, jet engines etc., no thread insert other than Helicoils have ever been specified for mission critical applications. If a Helicoil fails to meet a particular size bolt torque specs, then either the Helicoil thread was not made correct due to a wrong size drill or thread alignment, or the insert was not installed correctly.
i will say that if the insert has a piece of metal to hit it will swell some and tighten itself up in the case of the helicoil at least that is the way it was explained to me nice test
Excellent video comparison, I wonder if results would have been the same when adding an insert to steel? I have a wheel hub where threads are on their last legs from looking at video Big sert looks to be strongest, but that is really intended as you note in the video to be the thread repair when others have failed, would it make sense to go with the big sert from the start for lug bolt requiring 80# ft torque?
Honestly, being in the auto industry for many years I would replace the hub. I doubt the inserts would be stronger than the steel hub and you would be introducing another possible point of failure into a rather critical piece of the car.
Thank you for the video. I was going to use stainless steel Helicoils but was talked out of using them. The voice on the other end of the phone said to use Time-Serts instead. After seeing the video I don't see any reason not to use Helicoils on my project.
Very interesting. Over the years, I have used Heli-Coil very successfully. However, i always seem to get the Time-Sert argument and was ready to step up and try them on the next repair. In your case, it sounds as if the "voice on the other end of the phone" may sell Time-Serts. However, this test shows the Time-Serts to be nearly double the price of Heli-Coil and do not perform as well. Heli-Coil remains my choice. This reminds me of the various penetrating oil tests that have been published recently. The famous and hallowed Kroil, at 3 to 4 times the price of other common penetrants, did not out perform and in some cases failed to match the competing oils. This is a perfect example of the value of independent testing.
What I was looking for: Manufacturer's listed pull-out strength in 6061 aluminum: HeliCoil = 10,116 lbs; KeenSert = 9,239 lbs; TimeSert = no manufacturer listing
I just watched it. He went much deeper than my simple test. However, he ended up testing weaker 8.8 bolts to failure. I used 12.9 bolts and tested the inserts to failure. His video has far better production value and drama of flying parts. Mine is far more boring but I prefer the results I achieved.
@@RidgewoodMachine I originally watched your video last year and I was shocked that the time-Sert was inferior to the helicoil. I asked Project Farm if he could do some tests. Ironically both Torque Test Channel and Project Farm released videos for both of their tests (on the same day).
awesome video! like they say you have let the engineering facts do the talking ! how does the ns300L stack up to these? i am rebuilding my daughters and would like to make best choice
So my torque specs are 31 ft.lbs. on my drain plug… How can any of these options even work effectively? The margin of error is extremely small if i am to torque it to spec. It seems like the aluminum would definitely fail, and the helicoil would be close to failing. And i have 2 stripped oil pans now for the same bike… so im getting pretty frustrated and confused about my options…
Super! Thanks for being open to that. I don't have any right now -- I'm trying to decide whether or not to use them -- but if I can pick some up I'll get back to you.
I'd be curious to see what these would do witb a large bolt and harder testing material. We use key locks at work and they seem to be pretty decent. This on waukesha heads, large and cast iron.
Would you recommend Helicoil for a Cylinder Head Bolt Hole fix? I'm planning to stack 2 helicoils, use ARP Head Studs and torque to factory specs 49lb-ft. Thanks!
While Brembo calipers are great for stopping cars, they have a known issue with the steel mount bolts seizing in the aluminum caliper mount holes. Would you recommend these inserts as a good repair option?
when doing tests, stainless>aluminium. aluminium is not the same all the way through and has soft spots, basically it's more of a test on the aluminium stock then the inserts. i have to know these things as i'm a inventor and deal with material values .
VCMD propulsion but, did you know that I only had a 10,000 proving ring and already had inserts in those sizes? I also have a major project ahead of me that is largely aluminum. You dance with the feet you've got.
Happy to see the tests in aluminium, that’s the place I use thread repair systems the most, not often I have to use them in stainless, mild, or high tensile steel, it’s an aluminium alloy and cast iron the most.
I'm disappointed, I watched through the pull test and noticed that there is SEVERAL discrepancies with this test. Watch the "control" (14:25)and see where the side blocks are set then look at the same test (15:15).. now look at the helicoil (20:16). blocks are set solid next to the test. this is controlling the flex of the aluminum and thus holding the coil in place. Now look at the placement of the time cert (20:45). Recoil (23:25). Big sert (25:21) this one is the only other one placed as close as helicoil. I am sad that I can not honestly take ANY of these tests seriously. The torque test we had no way to see the torque wrench and verify it was actually at the values you stated. I would've like to see a better controlled test to see if they are all equally installed as well. O well, maybe next time.
This test indicates a standard tapped thread in 6061 Aluminum will have a holding force of 5000 pounds and the Helicoils create a wedging effect and go beyond that .
Look at the results again. The threads pulled out of the 6061 at a force that was about 10% less than the Helicoils. The inserts extended the strength but not by a great margin.
First, thank you for this video, I was leaning toward Time-serts but I'm going to use Helicoils now. QUESTION: I have a stripped hole for a head bolt; M11x1.25, 80mm deep hole, 60mm of threads in bottom. If I stack these (4, for a total of 60 mm Helicoil threads) does the torque and load capacity increase? As someone without a lot of experience I'm guessing yes, but I'd like to get the opinion of someone with your experience.
Helicoil makes longer inserts than the ones that come with the kits, but I had trouble finding anyone that sells them. Finally found a place in the UK, waiting for them to come in. Going to try repairing M11 x 1.5 threads for a Toyota head bolt. Not sure how you would stack shorter inserts, since the deep end of each coil bends across the bolt-hole so the special bolt that drives in the insert can get a grip and turn the insert. Seems like having those sticking out into the bolt hole in a stacking scenario would not work.
Great video! I’ve stripped the threads of my motorcycle’s oil drain hole, the bolt diameter is 10mm and about 12mm long. Which option would you recommend for this application? Thanks in advance
Personally, I'd drill it out and tap it with a 1/4" BSP or NPT taper tap to accept a tapered blanking plug (if theres enough "meat")... they usually take an allen key & they seal very well, are almost impossible to strip the threads ... but if you over-tighten in a light housing they can cause a crack... but I would still prefer 'em.. 🙄😂 BTW ... I LOVE helicoils... but not where oil-sealing is required...
Please give me some info where I can learn who makes the absolute best taps and the best drill bits for removing broken fasteners......I have small applications....6mm - 12mm. I just realized grade 8 fasteners are waaay too hard for off the shelf drill bits.....I bought some Champion/Brute and they are amazing...... but being new to this hardened stuff I’m list.....thank you.
Hi, good instructive video. May I ask you which method would you recommend when the damaged thread is short? I have seen thread repairs on long threads, say over 1 cm. But if my thread is only about 3 or 4 mm? many thanks
Victor G that's a pretty tough call without knowing everything involved like material, size, load, etc. Honestly, I'm no expert on these things. this video was made to settle my own curiosity.
I have purchased a set of Helicoil inserts to fix stripped out threads on a guitar bridge's fine tuners. These are actively used as adjustments and the mild steel of the original tapped hole just eventually wore out. Is there a specification or test for the durability of these inserts against active use and friction wear? All I know to do is grease up the Helicoil and hope for the best.
Great Review Video...I’m about to use a Helicoil repair on some Subaru oil pump holes...I found out I needed the M6x1mm kit, After purchasing an IRWIN brand 6mm x 1mm repair kit...I assumed that 6mm was the Same as M6 but it’s Much smaller in diameter. Would you happen to know the Metric equivalent to M6?
Great video. One thing that I would find interesting is torque beyond spec, remove bolt and retorque. In the field, this could be common during maintenance and repair. So say a 250lb gorilla torqued the 1/4" bolt to 45ft lbs on the helicoil, how would it stand up the next go around? I purchased Acme keylock inserts based off of field experience. It was nice to see the parent material failing before the insert. Thanks for taking the time to make this.
Makes sense that the bigsert held the most, it has the most surface area in the parent material. But I'm surprised the heli coil did better than the timesert, the timesert and bigsert are the same design, one just has a skinner body...
First time I’m seeing this kind of comment, are you saying that they made their drill bit in the kit to big ? , just got done installing 20 Time-Serts but they were so damn expensive it’s hard to sleep knowing I could have saved money with Heli-coils but something in me can’t trust the “Spring “ design . I was attracted to the “ solid insert “ aspect of the Time-Serts design among other things like the fact they expand into the workpiece & they only go as deep as you want them too during installation because the drill bit cuts a seat for it to rest on .
@@thelongranger55how did the Timeserts hold up over time? I’m interested because I’m looking to use them to do thread repairs for each of my head bolt holes (16) on my V6 engine block. Like you, I trust the Timesert design vs Helicoils since it is a critical repair.
All of the inserts pulled out of the aluminum. The Time-Sert was broken up when it pulled out. I, too, would like to have seen tests in iron, mild steel, stainless, and other materials. This test was laid out to come in just under the maximum capacity of my proving ring. I could easily do it again in other materials but I have no way to measure the pressure involved. Trashing stuff with hydraulics would be pointless without measurement.
That should not be a concern. In the tests I performed an 8mm bolt was holding 9,000 lbs of force in tension. When it comes to torque, all of the thread inserts exceeded the specification for the bolts. When you stuff them in iron the limits should be higher than they are in the aluminum I tested.
my 06 lly the oil cooler was leaking. so i thought. removed it and low and behold a idiot had been here before. the 8mm x 1.25 stud on the engine adapter plate for the oil cooler elbow had come out. apparently there repair using a heli coil did not hold. they used what looks like jb weld as well. also appears they drilled partly into the water jacket. i believe the reason for the jb weld. i drilled and tapped it out to 10mm x 1.25 reassembled the oil cooler and installed it into the freshly tapped hole. after filling the partially penetrated water jacket with water weld epoxy from jb weld..it failed. i installed helicoil it failed so now its time sert ,big sert or recoil. which one would you recommend thanks in advance
Best to use a high strength locking Loctite product to stop the inserts from ever pulling out. Oh now I see why they may not be holding, their being inserted into aluminum and not steel.
Kevin, my compliments on what seemed a thorough test but from my perspective not really one based on what threadcert would be best. You using it on aluminum never allowed the actual strength of the cert to be tested. If you had used them on steel and really put them to a test of their own strength I think it would have been much more informative.
I could only measure up to 10,000 lbs. These were pushing that limit. Besides, I was laying out a project in aluminum so that was the most logical metal to use.
@@RidgewoodMachine well I do understand it from your pointand hopefully someone will come up with a test that shows actual strength of the insert not the product it is being put into. I hope whatever your project was it turned out the way you wanted it to
Loctite would not have an appreciable impact in this test. The inserts are coming out because the aluminum is tearing or the insert is stressed beyond its limits.
