Making Square Holes With A Square Broach 

G'day everyone. I hope you like this fact finding video. I do apologise for the later upload and the audio quality. I've been moving houses (not moving workshops though) this week and I'm trying to record and edit this video on the living room floor with my dog trying to run off with the microphone, which is pretty normal for him. Should be more set up next week for a better sounding and longer video. Cheers

I'm glad you were able to broach this subject again. You really pulled it through.

That actually went a lot smoother and more straightforward than I was expecting, honestly. On to the splines!

To overcome the relative short length you could make multiple broaches that gradually step up in size and use them in series if you need to broach harder or thicker material.

I think you might need a cover plate that has a hole just big enough to allow for burr to minimize warping, or perhaps a sacrificial cover plate with just the exact size of the square hole on top Or even having the grooves a little deeper, it would sacrifice strength somewhat but could allow the shavings to be dragged out inside them. Anyway, I'm just spitballing, it seemed to work well enough already as you've measured in the end!

Congratulations on the 100k. And I'm impressed as usual with the creative home shop solutions you come up with. ❤

Well done, nicely made. Congratulations on your 100k too!

I just love how these bits look like a Shinto shrine.

Really enjoy the creativity and direction you take, thank you! 👍💪✌

Gratz on the 100k!

Congrats on the 100k of subscribers, well deserved. Legend.

Congrats to 100k subs you really deserve it.

I used to moldmaker work at a shop HI Life Rubber in Wisconsin that made milking inflations, those big black rubber things that they milk cows with. There was a bunch of these old molds from a company called IBA, they had developed back in the 60s a inflation design called engineered collapse, these were square rubber parts about 13 inches long (300 mm) and about 4 inches of the part was square. We didn't make these molds in our shop and I always wondered how they could put this square hole through 4 inches of steel. This was very mild steel, leadalloy, free machining steel. But still to push a 1 inch square broach through that much steel was pretty impressive. We started making modern versions of these square molds using S7 tool steel and a $250,000 four axis wire edm. That worked really nice, we'd go through about 5 inches of steel. These were big round parts, about 4 inches in diameter and a precision pilot hole to locate the wire with. It would take about a half a spool of wire and at least a day to cut the slug out. With the 4 axis machine we could cut square tapers, triangular straight and tapers, transitions from round to either a square or triangular hole on the other side of the mold part. Cool stuff, all you need is a quarter of a million bucks.

Good to see you hit the 100k - well done. Oh and a great vid as well😀

You (pulled) that off good 👍

That's pretty cool, man. Good luck getting settled in

very nice job, and gives me ideas for my fly press...puller , I hadnt thought of using it backwards so thanks for that one Thanks for sharing ...I need the roof on my workshop pronto

Baxedm has some good content about building a diy wire EDM machine.

Congratulations...! 100k subscribers ...

Congratulations on 100k subs

For someone like me who learned english at school some decades ago (british english as in most european schools) at the beginning it was not easy to understand everything spoken with this specific australian accent. But I got used to it and it pays off. Meanwhile I have watched every single of your videos and learned quite a lot!

Happy 100k❤❤🎉

Thank you for that video.

Happy 100K!!!!

Congratulations for reaching the 100K subscriber milestone. Hopefully this comment will help tickle the algorithm into promoting your content even more.

Nice work!

Congratulation on the 100k follower 👏👏

Thanks for sharing.

hoping for the best is always a good strategy

the great thing is you can use the same tool for push broaching, and since is symetrical in all 4 sides and pretty thick it wont tend to bend like a regular broaching tool. you can also make a "guide" for the broach to keep it perpendicular and supported, it works just like drill bit guides

A 10mm PC sheet should be a sufficient shield for any breaking broaches.

Good job from Texas, USA

Nice job! Another great use for the press.

Make a ROUND BROACH! Genius! 👍

Very interesting❤

GZ on 100.000

Since you're on a press kick, should try the opposite of a broach, a die - press or pull the workpiece through the forming plate instead of vice versa. Could get some nice shapes with a series of dies, and it's a fun fabrication challenge I think.

an EDM machine costs more than your entire shop combined lol. we have one at work. amazing machines with incredible accuracy.

In regards to EDM machine I've seen a few videos around where people have actually made them for home shops, think the 3018cnc or ender 3 printer level.

Keep it up Bro.

The Frankenchuck gives me the jibber-jabbers... any chance of doing a back-plate for the 4 jaw that'll let you mount it on the big lathe directly?

i don't think you've showed us a zoomed out view of the operation of the fly press since you build it! i want to see how that handle works in action

@clickspring would be proud!

It goes into the square hole!

@0:41 - I think that Applied Science has not only created a homemade EDM machine, but also made a water jet cutter out of a common pressure washer. I don't think the cost of either was too prohibitive.

No experience with it myself but I have seen people using an accurately machine split ring to hold a square workpiece in a 3 jaw chuck. Might be worth a try.

You could use an appropriate sized socket wrench into the 3 jaw to hold your square stock.

Square taper cranks on bicycles!!! I took mine off and put new ones on and now all I think about is square holes.

I love watching you make these things. Its a kind of satisfaction seeing that my mental properties of materials conform to reality...as an armchair observer these days, that's all I've got! I do have a question, shouldn't the broach scale up the shaft so the first cut is the smallest while the last cuts are the final size? That would've been done with a machining step or grinding the broach into a pyramid shape. Did you do that and I missed it?

For affordable EDM, the Rack Robotics Powercore seems to be a promising option... I haven't seen any proper reviews for it yet, but it does seem to work decently well. I wouldn't count on the accuracy, lacking a spindle and water flow, but it might be worth having a look at it if you're interested.

nothing to worry about clamping a 4jaw chuck in a 3jaw. I Was clamping a 250mm 4jaw on a 220mm 3jaw on cnc and it worked. Just have some common sense when cutting and u are good.

Pulling a broach looks to be a lot better option than pushing one, you could go to quite small sizes.

Put a link in the comments for the 4-jaw you can use on the big lathe!!

👍🖖

Sorry for the possibility dumb question but I was under the impression that O class steel should be quenched in Oil (compared to W or A class - water quench and air quench respectively) for best results. Is there some specific reason you went with O class steel and quenched in water?

The first time I saw a chuck held by a chuck the video finnished with 4 progressively smaller chucks from 12 inch down to 4 inch.With the lathe running each one looked like it was going in the opposite direction totally weird.

O1 steel is oil hardening not for water

Yep definitely not wrong about EDM being expensive. Im an apprentice at a machine shop in New Zealand. One of the machines i run is a 4 axses cnc die sink EDM. I think we payed around $120,000 for the machine a few years ago. And since its a very slow process the costs add up. I think we charge $45 an hour for machine run time and an extra $105 if an oprater is needed. Wier EDM is faster for this kind of stuff but the wier is a big running cost. And good luck finding a hobby leave EDM for the garage 😂

Don't worry we will follow you to the end of the earth

How much chuck can a three-jaw chuck chuck?

I keep wondering if I can put some top rake on the teeth. Last square broach I made was for brass so it didn’t matter. Kind of mushes in aluminium.

2:30 how many chucks could a chuck chuck if a chuck could chuck chucks??

Yo dawg, we heard you liked chucks, so we put a chuck in your chuck, etc. 😂

Why did you quench O1 in water?

Yo dawg, we heard you like turning, so we tossed your chuck into another chuck so you can turn while you turning...

I've never seen a pull press before

yo dawg i put a chuck in your chuck 🤣

THAT...? Is the "big" lathe....??

'EDM isnt my kind of music' 😂😂

Really should quench in oil but otherwise good job.

Build a homemade EDM machine

why didn't you do a push-broach instead of pull-broach? Seems it would have been smarter to avoid having a pressure plate and avoiding the bend problem alltogether. + you are no longer limited to a broach force of the tension strength of the bolts used to hold pressure plate in place.

better to push it through the material

"far less long" - is that the same as 'shorter'? When did you turn American?

7/5 bur removal noise

yo dawg i hear you like lathe chucks so i put a lathe chuck inside your lathe chuck

Used edms that need some love can be bought for around 2 K . Old stuff tho

did you make upsidedown? hehehe i know why you are on Australia

Dude , you need a bloody 4 jaw 🤣🤣 Nice job on the Press, handy bit of kit.