Making a Better Machinist's Screw Jack

Support my work on Patreon: / herschtoolroom
For today's project we will get started on making a custom machinist's screw jack.
I wasn't 100% happy with how my commercial screw jack worked, so I thought that I'd try my own design.
This project requires turning, drilling, boring, tapping, and knurling.
If you'd like to follow along, drawings for this project are available on my Patreon.
If you have any questions, criticisms, or suggestions, leave a comment!
#diy #hobby machine shop #hobbymachinist
My Lathe: MSC / Prince 9517350 - 13x40 Manual Metal Lathe
My Milling Machine: Bridgeport Variable Speed Series 1 "J Head"
My other Milling Machine: Brown & Sharpe No. 2 Plain "light type" Universal Milling Machine
CREDITS:
Music and Sound Effects courtesy of www.epidemicsound.com
/ @hersch_tool

[@argee55]

Looking forward to part 2.

[@hersch_tool]

thanks very much for watching!

[@foogee9971]

Nice job and great filming! 👍Thank you again...looking forward to part 2 😀

[@hersch_tool]

Thank you very much!

[@michaelclark9409]

Thank you for showing me your parting tool holder. I have never had that issue until just a couple of weeks ago. I thought I was going crazy! Nice work.

[@hersch_tool]

Haha, I mean you might still be going crazy 😂 😉but you're not alone on the parting tool, they are the worst! Thank you btw, and thank you for watching!

[@michaelclark9409]

​@@hersch_tool Fair enough. Thanks for snapping me out of my denial.

[@pikeyMcBarkin]

Really enjoying these new camera angles. Great work! Almost 6K ! nice!

[@hersch_tool]

thanks very much!

[@DontCallMeGarage]

i use a crescent wrench on the jaws of the chuck for heavy threading, the pinions of that scroll chuck weren't meant to be loaded sideways like that.

[@hersch_tool]

Yeah someone else made a very similar comment. Makes a lot of sense, it didn't occur to me at the time but I'll remember in the future. Always something new to learn, part of what I enjoy so much about machining. Trying to get a little bit better every day. Thanks for the advice, and thank you for watching!

[@jameshicks6753]

Ice job my friend, this could be a game changer. How ever , I think I will put two “V”s in the top maybe .15 deep?? 😮

[@hersch_tool]

Thanks very much! I've used it a couple times since making it and I like it a lot more than the other "jam nut" style I have. You'll want to use Pythagoras to determine your depth based on how wide you want the V to end up.

[@aaroncornforth2638]

when I tap acme threads I always set the lathe up for the thread pitch and rough the thread in with a standard threading tool. That removes a bulk amount of material and make running the acme tap in way easier. anyway nice job!

[@hersch_tool]

That's a good strategy. I don't have any boring bars or threading tools small enough for this one though, (I really need to work on getting some smaller boring and threading tools.) So I'd be grinding something, and at that point I guess I might as well just grind the acme tool and single point it lol. Thanks very much for the tip though, I'll definitely keep that one in my pocket for the future. And thank you for watching as well!

[@harry8506]

You can improve the AXA parting tool holder with a dremal by grinding a channel for the blade to recess in, I did that to mine and it was h huge improvement, better still is a spring type holder

[@hersch_tool]

yeah i gave up on the axa holder and just made my own parting tool holder. it's super rigid and works great. thanks for watching btw

[@localele1]

It should work fine with a few improvement ideas from the comments thrown in.My comment is to put a spanner on the chuck jaws when trying to cut threads manually.Save a lot of wear and tear on the chuck key.

[@hersch_tool]

That makes a lot of sense, I will definitely remember that for next time. Thanks for the tip. Thanks for watching as well btw. Cheers!

[@F1DesignUS]

Looking forward to part 2!

[@hersch_tool]

Thanks very much for watching!

[@lawrencesears7255]

I definitely think this is better than the standard design of jacks.

[@hersch_tool]

Thanks very much, I'm just hoping that it works in real life the way it does in my head lol. Thanks for watching btw!

[@Kami8705]

Looking forward to part 2. Wouldnt it help to make the bottom concave? It will be more stable and small chips on the bed wont be as much of an issue. I realize it doesnt need to be perfectly flat, but it would take one lathe operation and improve it easily

[@hersch_tool]

Yeah that's actually a great thought, can't believe I missed that lol. I'll definitely do that, will give you a shootout in the next vid, thanks!

[@randyshoquist7726]

Another way to get internal acme threads is to skip the tap, buy a nut instead, turn off the flats and leave it a cylinder, then bond it into a matching pocket in the knurled ring.

[@hersch_tool]

That works too! Thanks very much for watching!

[@highlandermachineworks5795]

That seems like more work.

[@randyshoquist7726]

@@highlandermachineworks5795Fair enough. But it saves the cost of buying a tap. Acme taps used to be pretty expensive, but affordable Chinese ones are all over ebay nowadays.

[@bheckel1]

My offcut from a recent part look now like a screw jack. will be a nice short one.

[@hersch_tool]

Haha nice! Thanks for watching btw!

[@skyfreakwi]

I'm sure i already commented but I'ma do it again... I feel like you need to chop that screw off and lock tite it into the groove. The other hole you have that goes to the bottom is the one that needs the brass thumbscrew. A big one! Big enough to cover the cut down locktited one so it disappears. Alright advice given, refresher rewatched, now onto part two!

[@hersch_tool]

LOL, thanks man, I hear ya ;)

[@bdove7939]

Very good work. Nice video.

[@hersch_tool]

Thanks very much, and thank you for watching!

[@thanos_vgenis]

I think you described the screw in-out operation the other way round

[@hersch_tool]

Lol it's possible, I am confused more often than not... We'll find out soon enough 😬 Thanks for watching btw!

[@ronmurphy9819]

I definitely would share this but I don’t know any machinest people.

[@hersch_tool]

Haha it's ok, I appreciate the thought! And thank you for watching!

[@zjtr10since80]

Good job

[@hersch_tool]

Thank you!

[@airmech6271]

Just a suggestion, identical materials tend to bind. Take a different material for the nut or put I a thin washer of a different material. Otherwise great and I enjoy your content.

[@hersch_tool]

Thanks for the info, I could slide in a brass or bronze washer without too much effort I reckon. And thank you very much, I really appreciate you taking the time to watch and comment. Glad your enjoying the vids!

[@ikkentonda]

That type of parting tool holder usually requires some "fettling" to hold the tool well. Note that not all parting tool blades have the same shape. Some cheap ones are simply rectangular in cross section, some have a bevel on the top, some are tapered on the sides, and some (like yours) are T-shaped rather than tapered. The T-shaped and tapered blades definitely won't hold (or cut) well in that type of holder unless you put some shim stock between the narrow part of the blade and the holder to ensure the entire bottom flat of the tool bears rather than just an edge. You also need a matching angle on the movable part that matches the angle on the top of your parting tool.

[@hersch_tool]

Yeah I think you did a pretty good job there of defining the problem. I prefer the T shaped and tapered blades. So the holder that I made has a relief at the top for T shaped blades, and an inward slanting angle at the bottom and on the top clamp piece. So no matter what, when you tighten everything down the blade is pulled in and flat against the holder. It's been a very rigid and reliable holder, despite the fact that it's one of the first tools that I ever made. Thanks very much for watching btw!

[@RustyInventions-wz6ir]

Nice job

[@hersch_tool]

Thank you very much, and thank you for watching!

[@Warped65er]

Thx for the vid.

[@hersch_tool]

you're very welcome, thank you for watching!

[@dennisbjones]

Maybe another tool to make is a c-spanner for the holes in the face of the chuck rather than mangling the chuck key and key sockets (during tapping).

[@4pawsforge273]

Your content is awesome! When are you gonna start fixing up that HUGE milling machine? Can't wait to see that! You mentioned in your video you need a camera person... you could spend months if not years teaching/training them to get the shots and angles that you are getting! So you do you and keep doing what you're doing. It is fantastic! ZERO issues with your video footage. I am NOT a machinists, (I play blacksmith) I don't even play a machinists on TV, and I watch enough content to be, at the very least, "I have seen that on 'TV' " James over on his KZbin at Claugh42 just did a video on parting off, speeds & feeds etc. that you may find interesting? The just is is go balls out on spindal speed and just "shove" that cutter in there. Check it out Stay awesome and please keep sharing. Love to see you work!

[@hersch_tool]

Thank you so much for the kind feedback! I really appreciate it. I really enjoy sharing my exploits in the shop, and love playing a machinist on the internet 😉 and yeah I'm a huge fan of James and his channel! I have actually been working on the milling machine in the background. Unfortunately I didn't film the cleanup. I tried, but it was just too difficult to do by myself. The machine was filled with what can only be described as toxic waste lol, and having to don all the PPE and get covered in the stuff, then try to take it all off and clean myself up to try and move the camera, then putt it all back on, rinse repeat... It just proved to be impossible. But you'll be seeing the machine on the channel very soon! Thank you so very much again for the encouragement and positive feedback. And thank you for watching! with all this support and encouragement I'm just getting started!

[@jimurrata6785]

The homage to Full Metal Jacket is on point. 😂

[@hersch_tool]

😉

[@jimurrata6785]

@@hersch_tool I imagine a whole bunch of your viewers weren't even born 37 years ago when it came out. Classic Kubric. He was a master. From Lolita to Eyes Wide Shut, stunning visuals and amazing soundtracks. Dr, Strangelove, A Space Odyssey, A Clockwork Orange, Barry Lyndon, The Shining. Every. Single. One. a Masterpiece!

[@hersch_tool]

@@jimurrata6785 absolutely agreed! Somehow we've gone from thought provoking masterpieces like 2001 to, the MCU... What happened??? Lol 😂

[@jimurrata6785]

@@hersch_tool It will not allow a single word movie title describing this situation. 🤔

[@jimurrata6785]

2006 comedic satire turned prescient, directed by Mike Judge, You guess.....

[@randymagnum143]

We just use 25 and 50 ton simplex jacks.

[@hersch_tool]

Rippin profile pic btw, love that show.

[@rjay1674]

I've been trying to find the scissor type knurling tool you use but with no success. Do you have a link or part number, for the one you are using? Thanks.

[@hersch_tool]

i got mine second hand, just about everything i have is second hand. But do a search for "clamp style knurling tool" and a bunch of options will come right up.

[@rjay1674]

Ok, thanks.

[@davidchavez81]

The lock screw feature is kinda wonky.

[@hersch_tool]

i mean, i stole it right off a southbend micrometer carriage stop, and it works great, 🤷‍♂️

[@ramentaryramblings]

3:12 what kind of insert tool is being used here and where do i get one 😂

[@hersch_tool]

It's a Swiss style from turning insert. Thanks for watching!

[@TheMadJoker87]

if you turn it clockwise and you want the screw to push out shouldnt be a regular right hand thread???

[@hersch_tool]

Yeah I was definitely describing that backwards... 🤦‍♂️ Derp

[@DavidLindes]

4:40 - question from a newbie: is there a reason you only go as deep as you do with the center drill? I've seen others go until about half-way down the wider angle. And it seems like your drill is plenty wide for that not to be too much for what you're doing, so I'm curious why you did less. (Maybe you were just taught that way, or self-taught and that's what made sense to you, or maybe there's something specific I'm not thinking of, or maybe the folks I've seen do it differently are doing something weird, I dunno. Just wanting to learn!)

[@hersch_tool]

Hey man, great question. A center drill has 2 distinct cutting surfaces, each with their own geometry. That wider section that you're referring to cuts a 60 degree conical hole to match the 60 degree point on a live or dead center. The smaller "nib" on the front is a 90 degree spotting drill, intended to accurately locate the hole and also act as a pilot for the wider section to follow. What you are seeing in the video, is simply using the center drill as a spotting drill, I'm not drilling for a center, I'm preparing to drill a hole so first I am accurately spotting the hole location using the center drill.

[@DavidLindes]

@@hersch_tool Got it. I think I've seen others use the second surface for preparing for drilling, too, but maybe I'm confused... because I've certainly seen (even in a later video from you!) folks doing the wider one for live centers, and that totally makes sense. Also, I guess the front cutter gives an extra gap for the tip of the live center, so that's cool.

[@DavidLindes]

P.S. Thanks for the reply!

[@hersch_tool]

@@DavidLindes yeah people will sometimes use the 60 degree section as a spot, but it's technically bad practice. Ideally you'd want a spot drill that is a larger angle than the drill point. Most drills are ~118 to ~135 degree. 90 is a happy compromise, 60 is way shallower than you really want.

[@hersch_tool]

@@DavidLindes you're very welcome 🙂

[@anthonycash4609]

Will you give the name of the turnning tool you were using and part number after you faced the part off. Ive never seen one quite like that. Would love to know where you purchased it from also. It left a very good finish.

[@hersch_tool]

it's an NTK cutting tools TFTR10X-IN-0H2. i bought it from someone on facebook. it's not easy to find the inserts though for some reason. like any insert tool though the finish is in the speeds and feeds. it likes high speeds and feed rates. i think i was at like 1400rpm and .0075 ipr on that cut and it really wanted to go faster. i find cnmg's to be generally pretty good for these hobby size lathes. thanks for watching btw!

[@anthonycash4609]

@@hersch_tool Thanks for the information and videos. You have a new subscriber

[@seanmcalum9238]

I also would like to thank you for the insider information for new guys starting out. I also am learning about tools and speeds/feeds. On the job training got me started down this trail 6 years ago and i've been hooked since. One question, how do you determine your depth of cut at that speed and feed? I have looked and really don't find anything about doc. @@hersch_tool

[@hersch_tool]

@@anthonycash4609 thanks very much!

[@hersch_tool]

@@seanmcalum9238 well you can look up machining rates for materials in SFM which will give you a rough idea. But for manual machining I have to say that for me at least, nothing beats experience. Whenever I work with an alloy that I'm not familiar with I will try to take some time to experiment. You start to get a "feel" for how your machine and tools react to different materials and you can make an educated guess as to about where you want to be, then adjust from there. With carbide, a dull finish often indicates that you can increase your SFM. Get in the handbook and read about SFM for more info on how the 3 things; speed, feed, and DOC work together.

[@keithmonarch447]

I'm not certain, forwarded a comment with you? I have watched a few videos. You well explain yourself along, prior to machining something. Where are you located? I live in west Michigan. Currently my darn email isn't working, in the meantime, take care and hope to hear back from you...

[@hersch_tool]

Hi Keith, thanks for taking the time to watch my vids, and thank you for the positive feedback. I am located very near Philadelphia on the east coast. Don't hesitate to send me an email if you get yours working. I enjoy receiving email about the channel and always respond.

[@YoSoyElQuesoGrande]

What instrument do you play? Or what compels you to have a sweetwater sticker on your toolbox anyways?

[@hersch_tool]

I played the guitar when I was younger, and I sang. And my father has played and sang his whole life. Around 15 or so years ago, my cousin and I wrote, composed, recorded, produced, and released an album. Even put it on iTunes just to say that we did it. Thanks for the question, and thank you for watching!

[@martinchabot_FR]

You were lucky that the loose blade did not grab and ruined your part... I always find parting difficult, even when I moved from 8x14 chinese lathe to a 14x24 old iron. Any setup error or too fast feed can go wrong in a snap.

[@hersch_tool]

Yep, I got REAL lucky there. I've found that when parting it pays to be aggressive. It's counter intuitive, but push hard and fast into the work and you will usually get "in front of" any chatter and things smooth right out. But like you said, parting can be hairy and can turn left on you in a hurry lol. This lathe is a good machine, but it's still an import, even if it's from Taiwan. And it just doesn't have the sheer mass of something like that leblond that I used to have so you have to really be on top of it when parting to keep this machine from wanting to chatter. Thanks very much for watching, and for the comment btw!

[@joell439]

👍👍

[@hersch_tool]

thank you!

[@kyriacosvasiliou8342]

Do you think power tapping with the ACME tap would have worked?

[@hersch_tool]

I think maybe with a higher quality tap. But this is a cheap import acme tap so I was afraid that it would be just as likely to shatter the tap halfway through. I could see the tap flexing when I was doing it by hand which is why you can see so much back and forth action on the chuck. It felt like, 1/16" inch progress, back up, another 1/16" back up...

[@kyriacosvasiliou8342]

@@hersch_tool yeah better safe than sorry

[@hersch_tool]

@@kyriacosvasiliou8342 yessir

[@EdJratNight]

This has to be the lamest machinist jack I've seen yet. The TPI should have been 24. The screw on the side is sticking out and needs an Allen key and I can only imagine how the post will lock. If you use 7 brain cells like you did, I can probably guess that it won't lock or it will lock in a totally re**** way.

[@SergeiPetrov]

using a lathe chuck key as a lever is a bad idea for a lathe chuck

[@hersch_tool]

Fair enough. But it did help a lot ;) Thanks very much for watching!

[@Skebtik]

What lathe coolant you use? Mine flings liquid all over.

[@hersch_tool]

Trim Sol, it gets everywhere too though.

[@craigsbully]

cool content, can you give me the vitals on the second turning tool you used in the video? Ive seen them but never inquired about them. Thanks Craig

[@hersch_tool]

Thanks very much. It's a TFX Swiss front turning tool by NTK cutting tools.

[@syldysnya]

Looking forward to part 2!

[@hersch_tool]

Thank you for watching!