Knifemaking Tuesdays Week 98 - Lathe spacers part 1

[@rippsgaragetech9025]

Nice! I was waiting for more videos of the lathe!

[@GeofDumas]

I know the feeling re: outsourcing. 400 bushings ordered and a vast majority had a burr and or were distorted from being cut with a very dull tool. Turns out the shop figured - it's for a knife - who cares? For shortening those spot drills, put them in a hand drill backward, then use a ceramic belt on the grinder while the drill is spinning. That's how I shorten my pivot pins

[@jbetts7978]

I love Shars for trying out new tools.

[@markparkinson5760]

Cool great video as usual cannot wait to see it used in anger so to speak roll on part two. Thanks for sharing Regards Mark Over the pond in the uk

[@MrLiamCooley]

Awesome cant wait to see next weeks video.

[@johnsaunders4227]

Nice job, John! Great video - nice to see the lathe producing such great results. How'd you end up finishing the shortening process - grinder?

[@goryl02]

Hey, as far as the main cullet is concerned you want the material to move absolutely freely when it’s open. That way you pretty much eliminate any inaccuracy along the Z axis, other than due to dull insert. I work in a shop where we do thousands of parts a day (lathes are running through the work week nonstop essentially) with the tolerances to within .00005 and when the cullet is set up right we can pretty much forget about the Z dimension. If there is any restriction on the bar along that axis, even a tiny hair, however, then there we get problems and the parts are too short. Granted the setup for mass production we use is different then what you intent to do, we use automatic bar feeders, the main cullet is responsible for moving the bar along Z, and there is another non-closing cullet just in front of the tools (which also has to be adjusted so that there is no play, yet the bar moves freely) but the principle is the same I think. BTW: I finally decided to get the job in a machining shop in no small part thanks to you and your videos so thanks for that :)

[@Prouisorsapientiae]

Like you said, the material should move freely inside the collet. The Tormach collets are probably cheaply made. The problem you mentioned about the "Z" dimensions wandering from foreign material is only a problem when doing 2nd operations on a standard 5c collet system. Even small changes in diameter will effect your lengths. It sounds like you are working with Swiss lathes, which use a guide bushing (the non-closing collet you mentioned) to support the material near the tools. In this case, it IS imperative that the material be clean and centerless ground because of the nature of that style of machining. I'm sure as John gets acclimated to the lathe, he'll try some better collets. Good luck with your new career.

[@JohnGrimsmo]

goryl02 Thanks for the tips and congrats on your new career!

[@russtuff]

Such awesome lathe! Fun video too :) I have that same micrometer but from Harbor Freight. It has been fantastic. Also, I buy all my digital calipers from HF, zero problems. I have not figured out why I need to spend more on big names because mine have not let me down once in 2 years.

[@JohnGrimsmo]

russtuff Agreed. I've had my same Harbor Freight digital calipers for almost 10 years! And other than changing the battery every 9-12 months and realizing that they do not like getting wet, they still work awesome.

[@russtuff]

JohnGrimsmo Yeah I've learned not to get them wet too :)

[@markrich3271]

russtuff I have a NICE set of calipers but use my HF digital calipers all the time .. Ive abused them too. Still going 4 years or so later.

[@spinnetti]

Good stuff... Looking forward to getting one myself. Couple thoughts - To cut hardened stuff: Just use a abrasive cutoff wheel - a cheapie HF one will whiz right through, then just clean up on the grinder - Measuring stuff: Accuracy is how close you are to the real number, and Precision is how repeatable the measurement is. Like you, on most of my stuff, I need it precise (repeatable), but accuracy is less critical. - High production shops get high accuracy stock. Just adjust your collet tension for the run of material you get, and do that each time (much cheaper than buying high accuracy material) - I hope Tormach makes a reasonably priced pneumatic closer... its pretty pricey already for a hobby machine. (I have the series III mill) - Gonna have to get me some of those form taps! Cheers!

[@Liberty4Ever]

SHARS - "There's nothing more expensive than a cheap tool." Shortening a carbide spot drill shank on the lathe - that's a job for a ceramic insert. Long ribbons of fire are awesome. One gang tooling strategy that might work for you would be a carbide insert outside turning tool on one side, a parting tool on the other side of your travel (one of these will be mounted upside down), and then have job specific gang tooling on a single riser block that drops into the middle and indexes on blocks to always mount in the same place. The advantage would be quick setups when changing between jobs. The disadvantage would be slightly longer travel between the two tools you use the most so your cycle time would increase by a couple of seconds. I'd definitely put an air cylinder on that collet closer. If Tormach is selling a CNC lathe of this size and capability, it should have a CNC controlled collet closer. I wouldn't even offer it as an add-on accessory. I'd just design it as a standard feature of the machine.

[@Max_Marz]

Hah that backstop is awesome, I am REALLY impressed with this lathe. I cant wait to see more. Can you get a get chucks for this lathe? If I could chuck up some ~3" max diameter aluminum slugs that would be fantastic.

[@JohnGrimsmo]

***** I'm impressed too bro, just wait till you see the next video, this thing can hold insane tolerances!!! Yes you can easily get a 3 jaw or 4 jaw chuck that should hold up to 15" diameter workpiece! 3" slugs should be no problem. And with a 3hp spindle it'll rip through 3" aluminum without hesitation. I used to turn 3" aluminum on my old lathe with a 1hp spindle and I would stall it every now and then.

[@Max_Marz]

15" swing? seriously? That thing must be way bigger than it looks. Awesome.

[@alexskrydlak7168]

You might already know/have discussed this (sorry if you did): Might want to start your setups machining 360 brass or similar, then change the bar to titanium/stainless. That way if you're off by a decimal or have a typo or odd speed/feed, you still have a chance to save your tooling. Also you'll have to buy less cheap tooling to "experiment" and just buy the quality stuff. When I worked in a screw machine shop, the setup order was always cut air, 360 brass, then final material. Also, rather than having the gang/bed go "home" at the end of a cycle, put a dead stop in there so you pull out the bar stock to the same position each time. You will probably get a few more pieces-per-bar out of it.

[@dennisskovgaard5526]

Hi. love your work. I always cut the spotter with a Angle Grinder. And to smooth the end, i use a handhold drill on a belt grinder. And it tuns out perfekt. It is much faster then to cut it on a lathe and program and set it up.

[@aserta]

Out of curiosity, did you at any point consider chucking the work piece in the mill's chuck and affixing the milling bit to the table? Then running it as a vertical lathe?

[@MrLiamCooley]

I believe he did that a long time ago to make his thumbstuds. Might be just dreaming but I remember a video where he did that.

[@JohnGrimsmo]

aserta Yes I did run the mill as a vertical lathe a few years ago, it works alright but there are lots of weirdnesses about it. writing code for it is very tricky, your workpiece can only go into the collet 3", and the collet tended to slip when drilling unless I made it really tight. Around week 29 or 30 I show how I did this.

[@aserta]

JohnGrimsmo Will check, thanks for answering.

[@Prouisorsapientiae]

I know you and TacticalKeychains have limited shop space, but you might want to consider a custom pneumatic bar feeder in the future. They are basically just a big air gun made out of threaded pipe with a pusher that fits inside. One end has a concave snout for your chamfered material to sit inside, and is attached via a roller-type thrust bearing. The other end has a grooved adapter with plastic sealing rings, and screws into the pusher. You could make a fairly short one that supports 3 or 4 foot bars. The material is always under air pressure, and is forced against a stop when the collet is opened. This would open up a spot for another tool where the puller would be. You would just set one of your turning tool "bodies" as a material stop/tool number, and program it to go to Z.020 or so after the cut-off. It would be a fun project if you had the time.

[@JohnGrimsmo]

***** That would be sweet for sure. Where my lathe is right now the bar feeder would block the door. With a bar puller I can run 18" bars easily before the material sticks out the back of the spindle, and that equals around 70 spacers which would run for over an hour and a half, I'd be pretty happy with that! If I were making thousands of parts like TacticalKeychains does then yes a bar feed would be almost necessary and definitely worth the work to install it. Heck, even just a bar puller but with a bushing behind the spindle so you could run a 4 foot bar without it whipping around.

[@JrFreak300]

Problem with the lower end mics is that their repeatability isn't that great either. You could do a gauge R&R study to determine the repeatability of that particular set of mics.

[@landlockedviking]

5:54ish , you mean more resistant to breakage?

[@CharlesSnyder]

Very cool, I'd be interested in seeing how you zero on this machine.

[@JohnGrimsmo]

Charles Snyder I forget if I showed it in part 2, but I'll show it in detail at some point. For Z I just use a piece of paper and jog each tool over in 0.0001" increments until it grabs, I'd say it's probably accurate to 5 tenths this way. For X I use each tool to skim a diameter then measure it and input that into the machine.

[@ThreeMuskeQueerz]

What are you gonna do for KMT 100?

[@d3pHc0n]

So many good comments. Tis strange to see KZbin comments that are mostly helpful instead of hateful. I assume it's because you're Canadian.

[@frollard]

It's so niche that the mainstream trolls never find it :)

[@Max_Marz]

When you close your collet without any stock in the collet you want them to close down to about 25 thou under the stock size, use a small hole gauge to check it, that should get you enough tension on the collet to hold strong and give you enough clearance to barpull effectively. This is how I was taught to run collets in cnc applications and how I set up my machine at work every day. We use collet pads however and it may be a different story. Maybe try what I say and see if it works for you? on that lathe you really shouldnt have much issues with stock pushback so you should be able to run those collets with a pretty light grip. Dunno if they make serrated 5C collets but we use them for troublesome materials. Hope that helps D:

[@Max_Marz]

What I can say for sure is that your stock should slide freely through the collet and grip down tight when closed. on the hardinge tool room lathes I've run with the same exact collet setup you really don't need to have much tension at all.

[@Max_Marz]

***** Another thing I am thinking, maybe you need to adjust how far your collet closer pulls the collet, looks like there's a threaded rod on the back side, have you tried that adjustment? Just throwing stuff out there.

[@Prouisorsapientiae]

Interesting. I was taught to never close the collet without anything inside/outside. This can actually cause the collet to permanently distort and change its size. I've accidentally done this before on external and internal collets, and sure enough, their concentricity went out the window.

[@Max_Marz]

***** Interesting, never had that issue but I do know that after reading a study done by hardinge that the accuracy of a 5c collet goes out the window VERY quickly with a size difference in your stock further than about 2 thou out and you start having major concentricity issues, Maybe your collets just needed to be splayed out a bit to repair their accuracy because they took a set slightly closed? Like I said I dont have much experience with 5C machines but the collet pad based machines we run at work have no issues with this. You can close them down so hard that the edges of the collet are hitting each-other and wont close down any farther and they just spring right back open with no problems. Just throwing my experiences out there in case something sticks :P

[@JohnGrimsmo]

***** Thanks for the experience! I've got a set of gage pins so I'll see how much it is closing. I think the tightness was just the material being over 0.250, since the collet doesn't really expand bigger than that.

[@conawayjb]

Get a cutoff wheel for the grinder, throw the hard tool in a vblock and hog it off and done.

[@donnanderson42]

I think the collet is too tight that's why it's hard to pull the rod out when you release it. you don't have to run it that tight, if the tool pressure is too much I bet it will break the small drill or tap before it moves the rod in the collet. Looks fun, keep up the good work! Donn KTM 200

[@MFGnerd]

And here you are looking at an 11000 Sqft shop haha ;)

[@johnchefnet]

John, If you decide you want to add a pneumatic collet closer it's pretty easy to accomplish by adding a pneumatics piston mounted between the head stock and the handle. Here's a example of it on my Hardinge with Omni-Turn attachment: kzbin.info/www/bejne/rJqroqF5btWIpqc

[@Regnarrussell]

Not an expert on your machine but wouldn't it have been easier to adjust the tool holder rather than cutting down the center drill? Looks like you have around 4 inches of adjustment.

[@frollard]

Definitely possible - however more stout = more strong, keeping them all chucked as close to the hold-down on the gantry gives a bit more of a solid connection (probably moot) but probably helps.

[@andregross7420]

Your ways don't look like they have a lot of oil on them. Collets are always tight when new.

[@markrich3271]

I know the Tormach 15L Slant-Pro lathe is bad ass lathe but why werent you using the 10x22 lathe you had. Seems like it would have been a cake walk for that lathe. As far as gang tooling goes you know you could move the collet shank out to keep the lengths the same.

[@JohnGrimsmo]

The 10x22 sucked compared to this, and it just had a cheesy tool post (although I could have made a gang block). It was getting old, needed a complete rebuild including new electrical and mechanical components, I just didn't have the time. And pulling the collet shanks out from the stop means they could slip if you put enough Z pressure on it.

[@dennisskovgaard5526]

make the spotter shorter then the drill

[@Slime_Greaseman]

Did you make your wedding ring?

[@JohnGrimsmo]

I did not, my wife bought it last year after I lost my original one (doh!).

[@CleanEdgeProductions]

You need some real calipers John! get some mitutoyo or starrett calipers

[@JohnGrimsmo]

CleanEdgeProductions Eventually I will, but for now these are doing fine for me. The new digital micrometer is measuring my precision gage pins to within 0.0001 of what they're labeled as, so I'm pretty impressed so far.