Why it's important to chase and clean your threads | DIY

Last week, Davin walked through the basics of cutting new threads in stock materials. That is all but necessary for fabricating new parts and pieces for a project, but what about threaded holes that already exist in parts you need to salvage? Then it's time to talk about chasing threads, and while it's a simple process there are a few tips Davin thinks are important to keep in mind.
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[@Hagerty]

Read more about it here! www.hagerty.com/media/videos/why-its-important-to-clean-and-chase-your-threads-diy/

[@chronoso]

Nice boroscope view on that second ID thread. Appreciate the camera work on this show as always.

[@nasilemak868]

I believe they use the LAOWA 24mm Macro lens

[@robbwallace7034]

You are a Master mechanic. We appreciate your talents and teaching us your skills. Thank you!

[@ChunkyMonkaayyy]

Davin is a great teacher and seems like cool person in general.

[@ChunkyMonkaayyy]

When I first started at a machine shop in high school, that was one of my jobs. Clean threads on everything when it came into the shop and again before it left. Hated it but man it really taught me to “see with my hands”. That and they had me measure everything in the shop. I spent a month alone measuring everything in the tool room. Got really good at that too.

[@abeclarkatp2595]

Hagerty is absolutely killing it with great content lately. Thanks to everyone involved for giving us great information in an entertaining fashion.

[@GalleryBones]

We can never get enough videos with Davin, he's awesome

[@sonyhk3824]

Agree 👍

[@Sackmatters]

I have saved so many hours with thread files. One important note I was taught from a machinist was to only file and lift off never drag the file back towards you. Even when using a standard file.

[@kw2519]

Yes!!! Files cut in ONE direction. Drawing back is the fasted way to ruin a good file. Also, get yourself a file brush. Again, only brush in one direction so you don’t ruin the brush

[@Sackmatters]

@@kw2519 file brushes are amazing for their intended purpose. A standard wire brush cannot clean the debris nearly as good.

[@tickandslug]

@@Sackmatters a regular wire brush with the bristles cut really short works just as well in my experience and that's what has been in most machine shops I've worked at because someone misplaced the file card and they need to clean some files so they just cut down an old brush.

[@Sackmatters]

@@tickandslug I’ve never cut one down before. I’ll have to give that a go.

[@SqueakyNeb]

I think the idea with staying in contact and NOT lifting off with this thread file is that you're always in the groove - you don't want to find your alignment again every single stroke, or bounce off the peaks of the thread and do more damage.

[@markk3652]

Make double sure to inspect the blind holes after cleaning the threads with the thread chaser or a tap. The debris that gets dragged loose can easily get packed in the bottom of the hole and compressed as the tool advances to the bottom. This also will affect torque values if it doesn't get removed since the bolt can't fully travel the intended distance. A stout piece of wire or a pick that reaches into the depth of the hole can break apart compressed gunk to be blasted out with compressed air. Also, a good bottoming tap generally won't change thread tolerances. The hole was drilled and tapped to be a particular size, and taps are pretty precisely toleranced.

[@chiil034]

Came because of a loose thread on my shirt... stayed for the video.

[@beri232]

I bet ya learned something too! Lmao

[@cameronkoehn400]

Need to get me a set of O.D. files. Never heard of such a thing. Learn something new every day!

[@belyear]

I love those files. So useful

[@Hoaxer51]

@@belyear, they do work well.

[@Icutmetal]

Got a triangular file? That works too.

[@TheApothecaryAus]

You can file a flat or a V groove (flat or triangular file) into a known good bolt (from your spares/parts bucket) to achieve the same without buying a thread chaser kit. A bottoming tap can also chase a thread with minimal risk of cross threading. Clean all threads with solvent too - important if there was loctite (or similar) applied previously (also implies it'll be applied again) I would also strongly recommend a wire wheel on a bench grinder to clean threads and finishing with brake cleaner/solvent if fasteners are being re-used, a bit of faffing about but far less effort than repairing a damaged thread because you were lazy. Tiniest bit (just a kiss) of copper grease on non-critical bolts (use engine oil or comply with Maintenance manual directions for torqued bolts) will help with corrosion prevention as well Hope that helps! Source: ex-Aircraft Maintenance Engineer.

[@joshuagibson2520]

Thanks for bringing this to the masses. Most folks who aren't machinists like us have no idea about a thread file. It should benefit a lot of people. You're right, that's not a tap. It's a thread former, aka Roll forming tap. It doesn't cut like a tap does. It pushes material to where it needs to go. When drilling and forming a fresh roll formed thread you actually use a larger size tap drill and the roll forming pushes the material toward the center and controls the minor thread diameter. Formed holes are not as nice or precise as using a tap, but theyre a great option for many situations.

[@Volterrific]

Thanks for this! I only needed one 3/8-16 thread chaser to clean up the threads for the exhaust manifolds I removed for sandblasting and high-temp painting. I found what I needed on Amazon for $8. Worked great! Glad I did not use a tap for this job. Thanks to your video, I learned that a thread chaser is the right tool for my job.

[@MaNu5755]

1:50 I'm happy to see that a man as experienced as he is still has to check which way his ratchet wrench goes 😂

[@cmccann4]

there's hope for us all haha

[@turogkane5826]

a good ratchet goes allways how the leaver stands so if its on the left side it will go left and lose the bolt ^^

[@christophercianci1366]

You just gave me a new level of confidence for the job I have to do. Thanks!

[@MadMathMike]

This is EXACTLY what I need to clean up some wheel spacers I bought that had some minor thread damage on the stud bolts. Thank you, Davin!

[@MrBblhed]

I added a set of thread chasing files to my toolbox years ago when I got out of the Navy. I have used them to save enough expensive parts to more than pay for them.

[@taze27]

Fantastic demonstration! I have rusty running board mounting threads underneath my truck. I'm going to use your tips. Thank you. God bless.

[@jeffjankiewicz5100]

Thanks for sharing that great tip Davin and teaching this old shadetree mechanic and others new tricks. Stay safe, God Bless.

[@eribertoacedo9505]

Thank you I have two sets of those chasers if I need to repair threads, sometimes the hardware stores are closed on holidays and Sundays may not be able to get replacement hardware so cleaning them up is ideal thanks again sir!

[@Hoaxer51]

It saves a trip when you actually need it if you’ve already gotten a set.

[@mr.b3168]

Where do you get thread chasers? All i find are tap and die kits for creating threads

[@johnmilner7603]

I bought a thread file with the pitch I needed from Princess Auto in Canada and it works.

[@reallyhappenings5597]

This is a very important part of a quality restoration, but it's also great to do as part of routine service. Any time I unbolt an engine accessory or manifold etc. off my aluminum engine, I make sure to thoroughly clean out the blind holes. I start with brake clean, then a plastic bore brush. Haven't had to use chasers yet but it's the same principle -- keep them holes clean and trim!

[@random_memory_dump]

Nice way of repairing threads on bolts! Thanks for the handy tips

[@PRRGG1]

Davin, great stuff! I am gonna wanna set of those thread files. While I don't work on cars, I work on television RF transmission line. It is normal threads get "boogers" as the manufacturer sticks them all into a loose bag. Great tip! If your ever down in Toledo, be sure to stop in at Tony Packo's.

[@Hoaxer51]

PRRGG1, not only are the hotdogs great, but the pickles are the best! My favorite from Tony Packo’s is their pickle and pepper relish, it’s great on hotdogs and other sandwiches! Go Hen’s!

[@rdyer8764]

Always great, even tho simple. Reminds me of stuff I've forgotten. Good that it's back in usable memory. Thanks.

[@mountainbiker4450]

Just bought a 2005 used Highlander and when I did the first oil change, I found that the engine drain plug bolt came out a little bit rough so I bought a chase from Amazon and intend on using it in the matter you describe. I was going to use a tap until I learned about these tools. Thanks!

[@carlodonnell146]

If time or access to a replacement bolt is a problem, you just may have to try and save the bolt, so it is worth it having one of those files handy just in case. Thanks for the info.

[@bikewolf7455]

rebuilding my first engine soon, had this video in my recommendations. im gonna look for a set of these thread chasers now. good to know about this

[@thomasrenia]

From Greece with love

[@thewholls7176]

As a DIYer I’ve always used the tap because they are super sharp and if youve got a good ear and a good feel you can hear and feel the difference between cutting baked on grease and junk from between the threads and cutting the thread itself the feel and the noise it makes is different and I think the tap leaves it much cleaner.......!!!!

[@Hoaxer51]

I agree, especially with a tap, I do own a couple thread files and they have come in handy at times. I own an old backhoe and I’ve had 1/2” bolts about six inches long with a nut on it and the bolt sticks thru about half an inch. The end of the bolts were buggered up pretty good so I used my thread file and repaired the threads before I took the nut off and it worked great. Saved the bolts and a bunch of trouble trying to get things apart.

[@danielbuck]

my thread chaser kit also includes thread chasing nuts, for OD threads. Those work really well for cleaning dried loctite or RTV off of bolts!

[@kw2519]

Spinning wire brush works really well too

[@justaguy8347]

Those worked great, I'm going to pick up a set!

[@krisraps]

WOOW! These Are Truly Wonderful Tips! Thanks So Much, And Greetings From Latvia. !

[@lucianmoon7755]

Im really glad I was recommended this video, thank you I learned a lot from this.

[@jeffplant3]

What on earth would someone give this video a thumbs down!!? Great video. Great education. 1,000 thumbs up.

[@chemxfan]

I need to expand my toolbox - I could've saved a small fortune in bolts over the years if I'd known about thread chasers!

[@Chanworx]

I don't know about you but I prefer to have gnarred threads and then ugga dugga them on with the impact until the socket breaks or the head strips. I've never had one come loose so it works 100% of the time!

[@mattsoares608]

They also make chasers for O.D bolts. Snap-on makes a kit and it has saved me me so many times. If you work on cars in or above the rust line - this is a necessary tool kit to get.

[@leafylotus]

This is awesome for people who learned how to wrench online

[@alex1949]

I've saved $1 bolts. When it 9pm and the car needs to get me to work the next morning, you do what you gotta do. I do have thread chasers that are similar to a die as well as the files. Saved my butt a couple of times.

[@johnlucic6608]

A little oil while chasing is good practice. Like this video.

[@reallyhappenings5597]

Yes but clean with brakleen afterward, then torque with or without the appropriate anti-seize or assembly grease

[@FurryWrecker911]

The timing of this. I just ordered a chaser set for a block I'm putting back together.

[@robertharker]

I like these DYI videos. Great practical advice

[@nathanrice1796]

Thanks for making a good video. Some hot rodders may not know about the existence of "thread files."

[@Onewheelordeal]

I love "As a for instance" for some reason. I recently was doing my brakes and used a tap and thread file to get me back home that night after any bolt store had closed. Bolt or threads into the caliper must've had bits of metal/damage in them upon previous assembly.

[@ShogunMura]

I really appreciate these educational videos, thanks guys!!

[@sparkplug964]

Learned something today, thanks.

[@donwest5387]

priceless tool. Didn't know that threadfiles had "square" profile

[@ukrsindicat]

Great camera work and great explanation

[@forevercomputing]

Small holes are easy, it's when you have to work in situ or with a large part. I bought used drive axles for my car and one side was fine, both nuts fit one side, but not the other. Tried getting a specialist until I realised I may as well tackle it myself. Whilst I had the kit out, I did the nuts and although it took me a couple hours, the results spoke for themselves. Had to clean the threads in my flywheel as well. Was resurfaced and I think it put a burr on the edges.

[@Wrenchen-with-Darren]

Well done. Thanks.

[@annw8909]

This is cool never knew about it.

[@Bari_Khan_CEng_CMarEng]

Great video and guidance, much appreciated

[@johnkenney7217]

Very articulate, thanks.

[@africanelectron751]

That was very educational... Going to have to make my own no way I will find those locally.

[@williamwallace5201]

Really good video. Thanks for sharing!

[@obsbarlos]

Awesome video as always thanks for this Davin!

[@JavoCover]

I didn't knew those thread file existed. I'm gonna have to get a kit of those, I used to repair threads with a small piece of sand paper one by one.

[@amorag59]

Sand paper!!? Oh gosh those poor threads!

[@levesquejp4964]

Would like to work with you on all these awesome motor from all era.. get hands on a piece of history everytime and feel what that was like to be living in these time

[@aaaabababa]

Thread Files can be absolute Lifesavers if you work on heavy Equipment with very big but very fine threads, like axle Stubs on semi trucks for instance.

[@bbreed1]

Great video man!! Holy cow. Amazing insight

[@chargerman426]

The set of thread chasers I bought years ago had thread chasers for bolts as well... its like a die so a bit easier to use than the file method.

[@keviny7963]

Very good info. Thanks for sharing!

[@rogjackson]

Excellent content. Can you do 2 Davin DIY videos a week please. Thanks.

[@viniciusareas5674]

Master class! Always Great!

[@jtw6458]

Super helpful, thank you.

[@benzina5917]

Outstanding video. Very well done and informative.

[@nepicness]

I didn’t know there were thread files, I’d usually it it hard with a wire brush and a triangle file. This seems more accurate

[@Riley_1955]

Same here.....I always look at bolts when taken out and clean them up and I don't have any of the tools seen in the video it's a wire brush on my grinder with a small file.

[@reallyhappenings5597]

If all you're doing is cleaning gunk, wire brushes are fine. It's only damaged threads that require filing. Gunk --> Rust --> Damage and each requires a slightly different approach, they are not the same.

[@nepicness]

@@reallyhappenings5597 Yeah I am usually cleaning gunk off. When I do need to actually touch them up I'll throw a threaded die on it or if I don't have it I'll painstakingly go at it with a triangle file. Definitely not the right pitch and depth, but it cleans it up enough to get it to engage which is enough for me.

[@valuedhumanoid6574]

I use my thread files all the time. And before I do anything, I will fill all the holes with a penetrating fluid like Kroil or just WD-40 and let it sit for a while. Blow out each hole and then the taps to chase threads.

[@omaralexander7406]

The video was helpful. Thank you.

[@chardon59803]

Good information there for sure !

[@kw2519]

If you need a ID thread chaser in a pinch, grind a couple slots down the length of the threads on a normal bolt.

[@byronakhavi953]

When using a thread chaser, the tool needs to be lubricated. Use cutting oil or some type of lubricant. First, use brake cleaner/solvent to clean out the threads that you want to chase (blow out with air). Then, lubricate the chaser and chase as shown. Slowly work in and out . If you feel resistance, work back and then slowly forward. Clean/reform the threads and then remove the chaser. Then use brake cleaner and compressed air to perform a final cleaning of the threads, after using the chaser. Insert the fastener by hand and confirm it threads properly. Kiss the fastener a bit and tighten it down by hand. Then torque to spec. with a calibrated torque wrench that is rated for 20%-80% of the torque range (if you need to torque to 50 lbs.-ft.; you will need a torque wrench with a range of 10-100 lbs.-ft. (your torque target is well within the 20-80% range of this tool). Then clean your chaser. Precleaning, using lubricant and post cleaning makes a difference. It also takes more time, and is worth the effort.

[@Limeayy]

Enjoyed it Davin!

[@beri232]

I wish I’d of saw this earlier today. I chased the threads on the heads of my Harley with a tap and it came out with metal filings…. I only wanted to remove old thread-locker… I stopped after 2 holes. Luckily I only turned it with my fingers and no wrench. I’ll know if I buggered it up once my gaskets come in and I torque it all up to spec.

[@Anatoli-y]

Very interesting info about restoring threads. Regards from russia!

[@markreynolds3850]

Thanks for sharing this video.great idea.

[@jamesdepaul3410]

Awesome vid, great explanation.

[@leelemon3373]

Great video. But you didn't show using some Lube on the chaser. I'm chasing my 4.3 L chevy astro spark plug hole. Lube on the chaser holds on to Gunk as I remove it and clean it and go back in for more. LOL Thanks

[@Cartier_specialist]

All these years I always thought I was cheating by doing this to my bolts and now I found out I was doing it the right way.

[@AndreiBanciu]

Well guess what ? Bolts also heave a "big heavy hex" end that you could drive with a socket ! :) Thanks for the video!

[@matthewstorm5188]

The problem with grinding a groove on a bolt in order to improvise a thread chaser is that it can be hard to clean the burs created at the ends of the threads. These burs can easily damage aluminum if you are trying to clean an aluminum threaded hole. Running a nut can help. But this may not be an option if you are dealing with a more oddball thread size. A thread file could also work - if you have one.

[@GamePlayShare]

I should get myself such thread file

[@JETZcorp]

How did the KZbin recommendations know exactly the job I'm going to be doing tomorrow? I've given them no clues at all, except for all the head gasket videos I've watched and Google searches about head studs. But regardless, considering that I do indeed have a couple unobtanium cylinder studs on this motorcycle and the only ones purchasable look like they were just fished out of the Titanic's swimming pool, doing a bit of thread recovery is going to be quite valuable.

[@brightenupcc]

Awesome presenter. Awesome advice

[@paulstan9828]

Learned something. Thanks!

[@TrondOleJensen]

Thanks for the great tips 👍🏻

[@rolandofunes6492]

Very impressive. Wow !

[@johnschutt9187]

Hey, Davin, Thanks for all the work that you do and for your videos. I really appreciate them. I have one minor issue that causes me to cringe. You frequently say things like, "I have went through..." It should be, "I have gone through." Yes. It's "I went" or "I have gone," but not, "I have went." Your work is so good, this slight tweak will help it to be perfect! Thank you

[@TheMrmmkkpro]

Should oil or pb blaster ever be used in this process? Working on a 1995 LT-1 corvette and the head bolt holes are real nasty, thanks. 🏁🏁👍👍

[@63nside21]

Amazing video! Ty sir😎👍🏼

[@NorthernChev]

For that bolt, why not just use the die that comes in the threat chaser kit? The external thread cleaner bars are more for something like that pinion you showed.

[@nickakers5160]

Good stuff!

[@jujuledruide6385]

thx a lot for demo !!! ♥

[@RustyDockLight]

Shop crane? What shop crane? 💪

[@jefferylara5775]

You should link in the descriptions some of the tools you use so we can buy the exact one you use. It'll also help give you some support if its an affiliate link💯

[@Grainsauce]

When thread chasing do you ever want to use any oil or lubrication or is it better to run it dry?

[@jaystrock613]

should you use parts cleaner or solvent while doing this? should you blow hole out with air? could you use wire brush on drill?

[@lucasstuart-chilcote7069]

Really great tips!

[@sausagedog52]

*sending it with the impact intensifies*