Thank you very much!

@@ProjectFarm Video suggestion (but certainly too expensive): automatic tapping mechanisms. Tapping heads of different brands vs FlexArm.

His testing is invaluable, especially for a DIYer like me. Before I try anything I haven't used before, the first thing I do is see if he has done something on it. The time and effort that must go into these is mind boggling.

They don't add to the video content... They permit the video content XD

Quite the exercise in patience on this one for sure! That's a lot of tapping.

Congratulations on the new house and thank you for the positive feedback!

I started to buy my tools based on his recommendation. Witch is hard, since not all brands are available in Romania… but now at least I know what to look at… specially when the seller is telling me a lot of marketing bullst… and I’m like We’re going to test that 😂😂

I tell literally anyone I know that’s looking for any kind of tool to watch his videos, very very good quality testing

the scientific method is a hell of a drug. lol.

Is it a new house or new to you? On a new house, or new cabinets, go through and try to tighten all the cabinet door hinges. My bet is that you'll find at least one, if not several stripped ones. I think this is due to the screws being small and the people at the cabinet factory being in a hurry with power drivers. Repair is a similar concept to this video, except you drill out the hole with a 3/16" bit, glue in a piece of 3/16" dowel, then redrill the hole and reinstall the hinge. Ask me how I know this.

Thanks for sharing.

I'm guessing that, since the aluminium remains the limiting material, they're stronger simply because of the slightly larger threaded aluminium hole having more thread overall, combined with a courser thread? So the strongest solution would be the one with the largest outer diameter and a course thread?

@@bakedbeings I would imagine that the insert would exceed the bolt of the same size as the steel insert would expand against the aluminum as the bolt pulls against the insert. Kind of like a climbing expander.

My guess would be that the inserts are steel inserts rather than another soft metal.

​@@bigrenegade7121 they are

Thanks for sharing.

Anodizing means that you are turning the part into an anode. Both stainless steel and aluminum work because they form an oxide so quickly that it forms a skin that protects the metal underneath. That means that if you scratch through it or prevent it from happening the part can be eaten up. That's why they will use a process to build up the thickness of that skin. With a conductive material instead of only getting heat when atoms combine you can also get electrical current. As in you can kinda think of rust being like fire since at some point if it happens you see flame but matter just has some basic ways it works so depending on how you add electricity to metals you can get reactions and with anodizing you are forcing it to react. If you mix metals they will make a battery and there is a scale of nobility if metals showing how much they react. Steel and aluminum aren't that bad normally but in an anodizing tank they will react. By having those inserts in there you probably had some minor changes to the oxide layer since it had to eat the steel before it would begin to work on the aluminum. You might also find it interesting that aluminums oxide layer unlike the chromium oxide layer tends to be a bit more open and thicker and is what makes aluminum special because it's really hard your average sandpaper that will cut even very hard steel is aluminum oxide. It's why it makes great boats since you have a soft tough inner material with an ultra hard exterior that self heals and doesn't wear much when you run it on shore. Some metals when you anodize or form colored oxide layers on them change the surface pattern so they reflect light different like a peacock feather but aluminum is different and they put dye in the mix that gets trapped into the skin. It just accurred to me that thermite is iron oxide and aluminum. Aluminum is extremely reactive and I don't know all the chemistry but once you get it hot enough it can actually pull the oxygen from the iron basically just pure rust to itself and burn it. It's not as reactive as magnesium but it's up there and can be used in explosives as well. A safety note is to not mix them when grinding at least on a large scale.

Also, holes are supposed to be masked off. Anodized threads are bad. Anodizing in threads can cause bolts to seize.

I used to work at a shop and we had that problem too... A couple whoopsies with batches of parts helicoiled before treating. They'd come back all blackened and stained and we had to redo the parts. Always fun redoing stuff in an absolute rush...

Want to remove steel bits from am aluminum part? Immerse it in a saturated alum solution. It will dissolve the steel out without touching the aluminum. Be patient…

Well stated! KZfaq and manuals are my friend. I always try to fix most things myself.

So many people discount helicoils. Being highly corrosion resistant, inexpensive, and easy to install, they are my go to for jet skis and automotive thread repair 🤙🤙

i learned about helicoils in Auto shop back in the late 80's, i had stripped a thread on a Holley fuel bowl screw trying to tighten it to get it to quite leaking gas. the teacher showed me how to take the carb completely apart and put it in the drill press, line everything up and drill it for a helicoil. I have been using them ever since, and i still hate leaky Holley carbs to this day.

@@shadvan9494 lol. I have a Holley I just rebuilt for my 72 f100 and it leaked all over. Had a spare Edelbrock I tossed on her, but battery is dead do I don't know if that one leaks too lol

Thanks and you are welcome! Thanks for sharing!

Thanks and you are welcome!

yeah. ezlok and any stainless coil insert seem to be great picks for a factory grade repair. I wonder if you could use a permanent loctite on the helicoil for frequent use. do the helicoils have problems backing out?

@@robomatt1600 I have heard of people using thread locker on inserts before to prevent the inserts from coming out when the fastener is removed, so I would say yes. I was rebuilding my brother's 4.6L 2 valve mustang engine (well known engine for spitting out spark plugs). It had a spark plug thread already repaired in the past with a time sert. The time sert was not put in with a thread locker (that we could tell), & because of this the time sert actually corroded to the spark plug so bad that we could not get it off to put back in the head (needed it for the new spark plug). So he ended up having to run one bad sparkplug misfiring really badly on one cylinder until we could source a new insert. Long story short I put thread locker on the new time sert before putting it in, & I always use thread locker on all of my inserts of any kind from now on just for peace of mind. Silly reason to end up waiting to be back on the road/track or miss a car meet/show.

@@robomatt1600 I was actually really surprised that the timesheet corroded to the spark plug instead of the aluminum. That part I still don't understand.

yes.. recently I needed severAl different size inserts. I knew I had some heli coil kits around somewhere but could not even remember what sizes they were... Did a search on Amazon and several kits With the Horusdy (which works exactly as the heli coil) not only being the cheapest but with the best selection. I am all about buying 'kits' these days. I did find the old heli coil packs I had bought years ago... None of em were the right size of course... and one of em did not even have one insert used the other two had one insert each gone. I probly paid more for those three packs of one thread than I did for the entire Horusdy kit. And.. it is all organized and in a big orange plastic case. Should be easy to find in the future. Oh... this is a metric and SAE kit with about ten sizes of each. Each has it's own drill and tap... and insert tool ... Very common sizes. Can't imagine I will need anything bigger or smaller in the future. Each size comes with about ten inserts. You can also just buy the inserts and use your own drill and tap and ciobble up an insert tool from a smaller bolt that you make a slot in.

Thanks for sharing! Glad that it has held up!

IDKFA.

Yes even the cheap kits are stronger than the parent metal, especially in aluminium alloys, as long as there is enough metal left around to spread the load. Also works for fasteners that are removed very often, so is very common in avionics as well to have 300 inserts in a unit to hold the screws that are used for hermetic covers, and on aero engines as well, in the assorted aluminium castings. Just have to use the right recommended corrosion treatments when assembling them.

The differences are more in how consistently you can install them. The chinese kits sometimes cross thread due to low quality installation tools that come with them. It's really hard to mess up a timesert in comparison...

helicoils work great, they increase the diameter that engages in the parent metal, which makes them a lot stronger than the original thread, and they take advantage of the lower elasticity modulus of aluminum, spreading the load over more threads. They help prevent corrosion between aluminum and steel fasteners as well. Only problem I've had with them is backing out due to poor installation, or using too short of a screw, and pulling out the first few coils.

And he hand tapped. I'm going going send him a tapping for him drill.

Thanks so much!

Insane amount of work. wow.

Haha, it took me a month to work up the bother to go outside and fix one stripped thread on a car engine !

I appreciate this channel and work he is making for the videos but... Because of my work, once a while I mark and drill holes into aluminium. Some days can be 500 plus holes...

Thanks!

Wow, thank you!

that would be 5 "half millions"

@@bndjaric ohhh yeah, or 10 quarter millions

@@GOAT_GOATERSON LOL

Thanks and you are welcome!

F

Thanks! Thanks for sharing.

That same idea is done in wood working with gluing in dowels to fix mistakes or fill in worn out screw holes. Any difference in strength is very minor as the wood glue is stronger than the woods used as long as you give the wood glue time to cure first.

I've done the oversized bolt trick many times in my little machine shop when i didn't have the right helicoil kit and it's always worked great and there's no waiting around for the right helicoil kit to arrive

I've been designing a light aircraft, and this has been an area of concern. The engine (85-90kg) is supposed to bolt to 4 points in an aluminium bulkhead/firewall. Which type of thread insert would you recommend, based on your experience? Please feel free to be as specific as you wish. Thank you in advance.

I have a 6.5 diesel block that was bought with starter hole problems. One hole is re drilled off center and oversized. Been thinking about having it welded to re drill. But now I think I'm going to try the oversize bolt trick and drill/tap it to OEM size and location. Thank you for the idea.

@@leoarc1061 they all work well, you just get a much larger bearing area for the same fastener.

I can answer that one from experience. Nope. It makes pretty close to zero difference

Thanks for the suggestion.

That’d be an awesome test, he could suspend a sheet of steel, bolt a transducer to one end (kind of like a plate reverb design), and then put a contact mic and an audio mic near the other end, apply a four foot square patch of each brand to the middle of the sheet, and measure what frequencies it deadens and by how much.

@@ProjectFarm If you ever do such a test, be sure to test for high temps and melting goo running out of doors. The brand I went with drips out of my doors years later and destroys my door seal no matter how many times I replace it. Huge mistake on my part.

Add 90# roll roofing to the sample list for siund deadenerst. I bet Professor Farm has som lying around.

Thanks for sharing.

Time-Sert is 100% legit. Love the design.

Thanks and you are welcome! Thanks for sharing.

I had to do multiple thread repairs on a Honda crankcase, not much material to work with. Heli Coils with their smaller diameter worked fine. An aviation technician told me that's all they use, and all OEM assemblies come with HC.

I've never used Time-Sert. I've also never had Heli-Coil fail on me, guess if they do I have a very expensive alternative now. :-D I was impressed with the fork repair, I don't work on motorcycles. I know that some of the structural adhesives used in collision repair are very impressive. I'm kind of wondering how they'd work for thread repair now, just for giggles.

A properly installed heli-coil will ultimately outperform any other threaded insert, heli-coils are approved for use in aerospace while time-serts and others are specifically prohibited. I wonder if the FAA, in conjunction with the entire aerospace industry, got together and used their combined experience with testing and engineering to evaluate the performance of threaded inserts.

Thanks and you are welcome!

Not a title to be given, or taken, lightly! But you are correct.

Immeasurable

@@megaluckydog1212 you don't say, lol. Do share.

Thanks, will do!

Thanks!

Thanks for the feedback.

Time serts are the best, but there are places only a helicoil will work.

Space to get into an area is always the tough part... even when lying on your back on the ground jobs need to get done.

torque test channel disagrees

I don't understand what's the point with these repair kits. You can just bore the hole bigger, make bigger thread and install a bigger bolt. Much easier than with repair kits.

Good suggestion. What is better than my old black and decker workbench?

@@sbukosky build one yourself. Will have everything you need (cuz you built it) and will fit perfectly (cuz you built it) and will make you feel good (cuz you built it)

@@doctordumbass9425 Some people value their time

The best sawhorse is the one you build yourself. Only you know what the sawhorse needs to sustain to be a valuable tool to you. I've never bought a sawhorse that could handle the pressure I put on too it with my foot to keep it stable. So I ended up reinforcing them myself

A 2x4 homemade sawhorse is the best because you can cut right through it

Thanks so much!

Thanks and you are welcome!

Thanks for the feedback.

I had studs falling out of the head of an engine. Helicoil kit I bought was solid. It became an entirely different car once that giant boost leak was eliminated, also an entire new set of issues 😂

"Mil-Spec", i's a catch phrase that sounds good but actually means nothing unless you know what the spec says. Without actual certification it is just a con like "Aircraft Quality" aluminum.

@@deconteesawyer5758 correct. In the case of the inserts it is materials, certification tracing, and certain thread standards. Just letting folks know it IS available. In a past life, using spec certified hardware was important (for some reason, the military cares about it, particularly for flight hardware). We didn’t even allow non traceable stuff in the building.

@@CharlesGallo If I want some Mil-spec hardware or aircraft parts I will contact the Taliban. They are currently better equipped with with that than two thirds of UN forces, as they were recently gifted 90 billion dollars worth. If l want a reliable insert with good quality control, material specifications, thread form, and strength I will just get a commercial insert from a good brand name American company like Heli-Coil and rest assured that it's tensile strength exceeds my needs. They are Mil-spec suppliers and have a ton of Mil-specs listed on their website, so there is a good chance the product is already Mil-spec without my thinking about it or asking for that. And in addition even if for some reason the product I selected was not Mil-spec they have the advantage of being produced in a quality conscious environment much like what you described working at, and meet or exceed numerous other quality, material, and process certifications. We can up that with NASA certified inserts, somehow important to space flight folks. I just want to make folks aware you CAN get those too.

Thanks and you are welcome!

Wow, thank you!

He is the absolute best. I feel like he could approach a tool company/monopoly and SELL this information for a TON of money. He doesn't operate like that. He helps the common man with unbiased, video proof evidence with absolutely ZERO BS and filler, or "please like and sub and comment and raid shadow legends" etc. You're the man dude! I tell all my family and my good friends about your channel. They always are somewhat uninterested because it is KZfaq but I say to give it a chance. They always are stunned how efficient and likable you are. I'll speak for him on this...remember to like the video, let him make some more money from KZfaq.

Thank you very much!

On average, it takes about a week.

@@markeymark5265 some of his test have lasted months for evaluation time

Pays very well per hr

@@safffff1000 You might be surprised.

Thanks so much!

Thank you very much!

Definitely. This guy’s channel is fantastic!!

Thanks for sharing.

Thanks broi

I've seen them break a few times, depends how they're done.

Thanks! Thanks for sharing!

Thanks for sharing.

Armchairhero : There are repairs that we dare not guarantee and whose reliability is sometimes surprising. :-)

Thanks for sharing!

live, die, modify

Ain't nothin' more permanent than a good temporary fix.

My favorite: A family friend (my wife's former student) was in college and her Honda Civic had a bolt strip (on the alternator bracket or tensioner) and each shop told her it was not repairable. Her parents were trying to convince her to purchase a new car which she could not afford. We were trying to convince her to repair the car and minimize debt. I ended up buying a time-sert kit and new bolt from the dealer and was able to repair it for her. She has since graduated and is an elementary school teacher, wife and mother. Her husband drives the little Civic as his commuter car and I can't help but smile every time I see that car or the time-sert kit in my tool box.

Thanks! Thanks for the suggestion.

I second this!

@@ProjectFarm I'd be interested to see how well something bigger like m16, m20 or even m24 would hold up with high tensile 8.8 or 10.9 bolts

Or engine head/brake caliper

Yes! The one time I had to do this was for a spark plug. I used a metal insert, but to lock it, you tapped the top with a provided punch to stretch the top and lock it into place. This was an extremely interesting vid for me!

Thanks and you are welcome!

Thanks for the feedback.

Wow, thanks!

Thanks for the feedback.

Thanks!

Thanks, will do!

I stopped watching the ttc when he got hired by a tool seller. The fact PF won’t even allow the appearance of impropriety keeps me subscribed.

Torque test channel is AMAZING too. Love both the channels.

@@rydplrs71 that won’t influence the results they produce

@@rydplrs71 do you know what they do in order to prevent contaminated data?

Look for a channel called "torque test channel" and watch their thread repair video it has batter information they didn't use aluminum so they had some thread repairs actually fail

You should watch the latest video from Torque test channel. They test these inserts with high grade studs and cast iron

@@juststuff4381 yea I saw that after I commented. But would still be interesting to see it. Most of the time when im doing heli coils it's in alum housings on engines. Very common for some jack azz go get over zealous tightening bolts with a impact and pull threads

The diameter is certainly important, but a second factor is that the pricier ones have one-piece designs so they won't 'uncoil' out of the hole if things get ugly. Far better repair for something that is going to be removed at least occasionally, but more money.

Im a machinist and at my work we used to use the helicoil ones, but switched to the ez lock ones. They hold up much better for bolts that are removed repeatedly. Most of our fixtures are aluminum and threads don't last long with repeated use.

Thanks so much!

Thanks and you are welcome!

I appreciate that!

Thanks for the feedback.

Yes, they last well there, and as a bonus the connection is always stronger than the parent thread.

@@ProjectFarm best wire splice connectors would be a good comparison video.

@@SeanBZA If the parent thread is an aluminium alloy. If the parent thread is some higher end nut like 12.9 grade, I doubt a helicoil is comparable.

@@jpikl1284 Still will hold out, as the larger diameter thread into the parent metal resists the pull, plus it is spread out over a larger area of the very hard wire.12.9 grade yes it will still rip out, but at a much higher load, and you can always use a much longer insert or multiple inserts, as I have done on deep holes.

Thanks and you are welcome!

Thanks!

Thanks, will do!

Agree. Have you seen his test on scissors? That one gave me carpal tunnel.

Great feedback on the Heli Coil kit. Thank you!

@@ProjectFarm My cheapest ones were actually US standard sizes, they had not moved off the shelves for 40 years, since the country went metric, so were finally on sale, for only double of the price in 1970, so I picked all of them they had up. Only 3 sets, but covered all the US standard sizes I used on US built machinery, 1/4, 5/8 and 7/16 standard thread. Also got the 7/16 die nut, so I could make the shear pins that used that thread, instead of ordering them, at a ruinous price. 1metre of 12mm stainless steel hex stock made a large number of those shear pins for use. Machining the pins, plus the tooling, came to the cost of only 1 pin, and I got over 20 of them, with bar left over.

Thanks!

Not only better holding power, but also better durability if it's something that's threaded in and out regularly.

You are welcome! Thanks for the feedback.

well for aluminum bronze inserts are harder and you have also corrosion resistance. I was thinking he was going to test it on mild steel with 10,9 bolts, with that setup its only interesting with the chemical repair

@@scasny Well having tested Helicoil in aluminium i have broken M6 12.9 bolts. Can not say much about the other brands though.

Exactly. My edelbrock victor jr aluminum heads, for a small block Chevy have helicoils installed from the factory. (rocker stud holes, and exhaust Manifold holes)

Thanks! Thanks for the suggestions.

I noticed that those bolts broke. That means next time use a stronger bolt. A broken bolt means the test for that product is incomplete because you aren't supposed to be testing bolt strength.

@@leewilkerson8185 So what if he goes with grade 8 bolts and they break? Or the inserts pull the aluminum threads out with them? We could do this forever, and eventually he’s spending a lot of money testing exotic metals to find out the best way to repair damaged aluminum threads. Best way is when possible just chase the threads with a tap and be done with it.

@@308dad8, why don't you use a thread chaser next time you lose the threads from a spark plug blowout and then report the result!

@@leewilkerson8185 The thing about Project Farm is that he performs experiments and reports results in an operationally representative manner. For most people, the difference in strength between the inserts is irrelevant. The question is just, given typical loads and materials, will this insert hold up better and give more consistent results than glue or nothing at all? The answer was a resounding yes. If the insert is so strong that your typical bolt will break before the insert does, that's all we need to know.

Thanks and you are welcome!

Thanks for sharing!

Thanks for the feedback.

TBF it shows the tests aren't so consistent. It would be much better if he used a longer flange and a steel washer because the aluminium got all mangled up and caused friction...

It would be interesting to repeat the test with a high strength bolt, as well as a washer to protect the surface of the aluminum.

If it’s statistically different it has to do with a variable thread pitch. On a straight threaded hole and bolt only 1.5 wraps of thread hold the entire load. If the insert stretches it could possibly spread the load further. The head or the top of the threads on a partially threaded bolt are where stress concentrates to cause failure. The fact that the grade 5 bolt broke says they will meet your needs.

I'm not sure how to interpret that. I think ultimately they should have been tested with some sort of washer and bearing surface to reduce the influence of the insert 'biting' the bottom of the bolt head - almost certainly the reason for the increased torque on the EZ lock. It may have tested be higher, but I don't think it's a benefit either way in a real world scenario.

Thanks for the feedback.

@@ProjectFarm I had to use helicoil for a timing belt idler on my subaru engine block and I've had zero issues. I can safely recommend it for moderate load applications

Thanks for the feedback.

The thread shouldn't be sealing anything anyway

For something like a drain bolt, you just need a flush surface and a large enough crush washer. Or a Dowty seal, which is a steel washer with a O-ring inside.

I agree, i gasket should take care of sealing. The repaired thread should take care of evenly distributing load over a gasket face.

EZ Lock is also not regarded as gas tight unlike Time Sert which is regarded as gas tight thanks to the insert being expanded when it is fitted. The biggest disadvantage of EZ Lock, Helicoil and HHIP is that they tend to unseat themselves in applications which require frequent disassembly (maintenance covers, spark plugs or sump drain plugs). EZ Lock is worst in this regard especially in assemblies which experience considerable heat cycling and can be slightly improved upon if it is fitted using thread locking compound which both secures the insert and gas tightens the thread. A further disadvantage of EZ Lock is its size. I work on motorcycles and in many cases there is not enough space to fit an EZ Lock. From 25 years of experience with hundreds of Time Sert repairs I'd say the system is absolutely worth the money and the repair will not fail as long as it's executed correctly..

Yes, this is the real concern with thread inserts.

Thanks for the feedback.

Indeed one of the concerns. Like in some applications with water pump installations, standard steel bolts are used. Eventually pieces weld together. Timesert makes inserts in stainless steel. Probably a better choice for aluminum.

Thanks for the suggestion.

One of the inserts operated in the same manner, didn't it? With tabs that had to be pushed down to lock it in...I can't remember which one though.

Great product choice!

Thank you!

Thanks for sharing!

Thanks and you are welcome!

Thanks for sharing.

You are welcome!

You are welcome!

Can confirm I've got a 5.4 in an F250 and lost some studdage, on the exhaust manifold. That's something that just shouldn't happen ever.

Another reason for this on the Triton is that the wall around the combustion chamber is thin, so the length of threads is too short for aluminum. It's more like what you should have for an iron head.

Blew 2 spark plugs on my 2003 Cobra (4.6 liter engine). Used the time-sert one time and heli-coli the other. Both held up. Those engines were notorious for blowing plugs.

I blew a plug thread on the barra, helicoiled and back to driving 1000km a week. Built Ford tough!

01 f150 with the older 5.4 blew out the front 3 on the passenger side mechanic put the helicoils in no more problems (kinda waiting on #4) but she has over 350 thousand on her! a great products made her run a lot longer!!!

You are welcome! Glad I could help!

You are welcome!

You are welcome!

If a heli coil is set properly (at least 1/2 turn below surface) it won't back out... I've done dozens working in bike shops, and always had better results with heli coils than time-serts.

People forget to set the insert as described in the instructions.

Same here. I have used the time-sert set for several spark plug holes in aluminum heads over the years. It can be done without removing the head, and without any extra tools. I have done several small outboard motors this way. Time-serts are really great.

Thanks for the feedback.

@@tdc7 the glob of grease to catch the pieces is probably what he ment

​@@tdc7 Tapping isn't the messy part, since taps hold grease really well to trap shards. You aren't removing very much material when tapping anyway. It's the hole boring part that is messiest. The Timecert that is large enough for a spark plug comes with a hollow boring tool, which holds grease extremely well. That boring tool is also really easy to use with hand strength. A typical spiral drill bit you use for helicoils is really hard to turn by hand. You want to drill by hand, since that keeps shards from flying and keeps the grease from being flung from the bit. The Timesert boring tool also aligned itself perfectly with the stripped hole. You would insert a pin into the stripped hole, then the boring tool would slide onto the pin to keep it perfectly aligned. This further helped with keeping shards out of the engine.

You can stop shards/swarf ofalling into the engine if you turn the engine to a position where the exhaust valve or port is open on the cylinder you are working on, and connect an air blower to the exhaust pipe.

Thanks!

Thanks for the feedback.

I use time serts after I owned a North Star engine that stripped out almost all the head studs. They multiple lengths also. Not sure about the other brands though. I always red locktite my solid inserts also.

@@soullesssol7285 i never trust that 'no thread locker needed' and use some, anyway.....never had one fail yet.

Thanks for the feedback.

Thanks and you are welcome!

Thanks and you are welcome!

Thank you!

Thanks for the feedback.

It's funny you bring up wood products, that's how I started using E-Z Lok in the first place after some generic wood inserts started pulling away after a few years on a table I built.

@@emotionz3 Yeah and I've never used the wood ones, but they looked amazing. Glad to know they work!

Good insight there. I think they’re all good, but I can see helicoil possibly to get damaged or even undone.

makes sense, i wonder if the helicoil kit was Stainless. Did not corrode, and tends to gall. Sounds line SS to me

Thanks and you are welcome!

Thanks! Thanks for sharing.

Thanks for sharing.

all inserts fared equally well I would say, doing better than the original test piece under torque load. I guess turning the bolt into a higher diameter bolt in some way could be the secret here. For the bolt breaking different geometries may be relevant here, as with the bolt breaking, this more tested the bolts strenght than the insert, geometry and size or smoothness of the insert may well cause the varyations here. Which however does not render this test irrelevant, as it shows it is now the bolt we have to worry about while the insert is fine. But the JB weld and the Loctite thread repair did also better than I had expected. I guess for certain applications with lighter torque and push/pull loads and hard to reach bolt holes, they may indeed be an option. Even the thread locker did more than I expected, and to be fair, this test was way out of the products "comfort zone". For the second test, I think we can conclude the the bolts tensile strength was reached at around 1000 psi in this setup. Not sure what that would calculate as in foot pound or Nm. I wonder what those results would look like with a higher tensile strength bolt. I guess at some point the insert would simply be pulled out of the aluminium at varying forces. the higher diameter inserts may be at an advantage here.

Thanks so much! Thanks for the suggestion.

At my work we have an old de-watering auger with a cast iron cover. This cover get removed everyday for cleaning. Over the years the threaded inserts had stripped so I ordered some heli coils. As long as you have the proper size and thread count and you dont overtorque them too much the coils shouldnt creep out. These were 316 SS bolts into a cast auger cover.

As an engineer at a cheapskate factory, I use a lot of these spring style thread repair kits in equipment that gets hot or wet, bolts that get tightened down with far too much torque and bolts that come in and out dozens of times each day, the inserts just will not back out no matter how hard you try but can work their way further in. In general the thread repair isn't the bit that fails, it's usually (and in aluminium always) the base metal that fails first, they don't really rust or get bound up. Their only weakness is if you ram in a damaged or cross threaded bolt or don't realise it's a thread repair and try to run a tap down it. Then you get to suffer.

For heat concerns - we use heli coils in the hot section of turbine engines for threaded hole repairs. If you're concerned about backing out the coil, stake or peen the top and the thing is never coming out... but you've now made that a one time repair. Soft aluminum/magnesium casting for propeller gearboxes, we use threadlocker to prevent backing out.

I suppose if you were concerned, you could glue the insert in with the red Loctite.

Thanks!

You are welcome!