Machining a Servo Housing! WW135
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- čas přidán 7. 09. 2024
- Precision Machining a Servo Motor housing on the Tormach CNC Mill and using the Emco V13 manual lathe to bore out the diameter! Checking our work on our new Mitutoyo height gage
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G'day John, the good thing about machining is there are many different ways to do a job. I'm the complete opposite to you; a manual lathe guy. In my opinion you ran the job backwards. A few suggestions FWIW.
A good rule of thumb (and how to make more money on jobs) is every setup you do reduces your accuracy and takes time. So try to use the minimum setups possible and try to use the same feature if possible. That way you don't stack tolerances.
Take your raw sawn stock and set it up in the 4 jaw so it's centred. It's square stock so you run an indicator along each edge to centre it. That won't take long as no special precision is needed. You then SPOT drill the face, drill and bore as you did.
Your lathe is boring a taper, nothing to do with runout. Was it correctly levelled as that's a serious amount of taper? Many lathes are not correctly setup and therefore cannot do accurate work. A lathe doesn't care how the stock is setup or its shape, so the stock can runout all it likes, if accurate it should turn without a taper and yours isn't.
Once the bore is complete (in the still rough stock), face the end. The bore and that face are now perfectly perpendicular. You still haven't done a setup!
Remove from the lathe and put in your vice with the machined face down. It will seat on that face. That is a large enough bore to be able to pass a DTI down inside so sweep the bore top and bottom to zero it and confirm the bore is aligned with the Z. Use an inspection mirror to see the DTI. Face the other end (now the top) and put in your features. The bore is the master feature of that part so you setup everything in reference to it.
Remove the part and put it horizontally in your vice. Indicate the bottom of the bore at both ends to get it level. Face the top and drill your hole. A tip is not to worry about that break through diameter. Look at the model and find the breakthrough diameter and use a smaller diameter drill to create that diameter. Follow up with your tapping drill and the depth isn't critical. Flip the part and face that side. indicate the bore as you did previously if you need tight tolerances. Rotate 90 degrees and repeat to finish the part.
FWIW I don't recommend using long series drills unless required. Good on you for putting up fails. I LOVE that height gauge, they cost an absolute fortune but are SO nice.
Damn Pete, this comment is amazing. Really gave me a new perspective on the process behind machining a part like this.
Pete F i
dang Pete think you have done this a time or two lol
Well said Pete, but I would've tackled it another way.
I would have done all the milling to the part first, then made a fixture to go in the lathe that held the part concentric using the bolt holes to hold it down then proceed to turn the bore.
"Remove from the lathe and put in your vice with the machined face down. It will seat on that face."
No, it won't. The back vise jaw will will determine how the part is positioned. If the bottom surface is out of square to the back surface, the bottom surface will lift off the bottom of the vise as the jaws are tightened.
I agree with your other observations.
You can use an annular cutter to rough bore the hole out first instead of step drilling it. It is basically like a hole saw except more efficient. It is clean and precise and you won't have too many shavings to deal with. We use them all the time and they work really well for us.
Yes, a kind of quasi-trepanning.
Hi John, I really enjoy your enthusiasm and your videos.
FYI A Tapered bored hole is only explained by the chuck axis not being parallel to the the Ways. You need to check and tram your lathe head bearings to your ways.
BTW with only giving 10 seconds of though to this, if i were to make this part I would have gone to the lathe first, faced of both ends and bored the hole AND then turn a 1/8" wide reference OD (ideally equal to the face to face width but that dimension isn't critical as long as you know what it is) on what will eventually become the bottom face of the part (have extra stock on part for this step) this reference ID can then be used in the mill squaring up steps to make sure the 4 sides are not only square but the right distance from the bore centre, by sweeping across this OD to get reference distance to bore centre.
Then go to the mill, use the two faced-off surfaces as reference to square up the rest of the block using the OD as reference to get the face to bore centre distance correct, then with the face with OD ring down sweep the bore to get the part centre and proceed to drill the holes. Final step mill the back face down to height thus removing the reference OD.
Alternatively you could have the OD face as the top face sweep the bore for centre and then and mill the up face to height & thus removing the OD ring before proceeding to drill the face holes.
note: when sweeping the bore to find centre, it should be done at the top and bottom (or as far down as possible) to reconfirm the bore and thus up face are parallel/square to Mill spindle
Cheers
You know... I'm liking this new style of video a whole lot!
same here !
John, the parallelism problem was probably the result of your measurements as you set up in the lathe. You got your face center right with the dead center trick, and you got the face reasonably perpendicular to the lathe spindle axis. But that face isn't what counts. What counts is the sides of the part. You assumed the face was perpendicular to the sides, and that one thou you were measuring in the mill probably added up with some other differences to give you your total runout.
You probably should have swept two (or all) sides of the part from front to back checking for runout. That would have got the finished bore parallel to the sides of the part. Then you could have faced the part in the lathe rather than the mill to be sure the face was perpendicular to the bore axis. While you could have done the part in the CNC lathe, you could have got the same error there, too. Since you want the bore parallel to the sides it would probably be easiest to finish the sides to tolerance before boring, then face the ends to length after boring (to make measuring in the lathe easier).
Yep, I was wondering why he faced the sides after he bored the center. czcams.com/video/rmlvsTsZeoA/video.htmlm19s
I also think that it has to do with the runout of the face. Even if it's 1 thou runout, he measured over a relatively small radius, so it could quickly add up to a couple of thou over the total length. He said something of 1.5 to 2 thou on the surface, so if the length of the part is 3 times the diameter of the circle the measuring tip is on and the center hole is centered, the other side should have a runout of 4.5 to 6 thou.
While the setup process you mentioned might explain the hole being off-centre at he chuck end, it does not explain why the bored hole is only 3 Tenths over at the face but nearly 7 Thou over at the chuck end.
When it comes to boring a hole, variation of diameter along the length eg taper has nothing to do with how the part is held in the chuck, you can set up a part completely eccentric in all axis and still bore a parallel hole, its just rhat hole will be completely eccentric to the other features of the part.
A Tapered bored hole is only explained by the chuck axis not being parallel to the the Ways.
BTW with only giving 10 seconds of though to this, if i were to make this part I would have gone to the lathe first, faced of both ends and bored the hole. Then turn a 1/8" wide reference OD on what will be the bottom face of the part (have extra stock on part for this step) this reference ID can then be used in the mill squaring up steps to make sure the 4 sides are not only square but the right distance from the bore centre.
Then go to the mill, use the two faced-off surfaces as reference to square up the rest of the block using the OD as reference to get the face to bore centre distance correct, then with the OD face down sweep the bore to get the part centre and proceed to drill the holes. Final step mill the back face down to height thus removing the reference OD,
Cheers
Charlie Brumfeild, its not true that you need a squared up block to bore a parallel hole. I could bore a parallel hole though a completely irregular shaped part, its all about the Ways being parallel to the chuck axis , nothing else.
+russhelmy I thought he measured runout, not diameter error? In that case you would be correct.
edit: yes, you're correct, my mistake.
I love the fact that you own up to your mistakes. I'm not a machinist by any stretch of the word. I'm a mechanic in a factory and I work with so many people that blame everything besides themselves when they get something wrong. I mean, how hard is it really to admit you messed up?
you said it right. machining 101 "square up the block". The whole block and nothing but the block. ;-) first. It's really good to see when things go a little wrong. seems like everyone learns more from errors than from perfection. keep it up. really enjoy the channel.
I like that you're not too proud to own your own mistakes, it is probably the reason you have come so far.
I love that you show some of the goofs and mistakes. The difference between a good craftsman and a great craftsman is how you recover from mistakes. No matter how good you are, things happen. It is often said there is no learning in success. Thanks for another great video!
John long time watcher first time commenter. If you want to make to process faster then you should use less drills in the process. The best way is to measure the chisel edge and then drill as close as possible and it will suffice. Then go in with your drill of your hole before the bore. The other benefit is that it will make for less sharpening of drills since you are using all of the flute to cut and not just the outside edges. Also this will help to eliminate runout when drilling with larger drills. Since you have so many drills in the process then you're more likely to to have one push out sideways when it's only contacting part of the flute.Second option is to use a spade drill and just cut one hole to your size. my vote is spade drill. I work on a manual lathe and if i want to set up for a bore quickly I will spade drill the hole out. The spade drill does not require a center before you drill. Both ways speed things up but since drills are cheap and spade drills are expensive the first one is cheap.
Hey John. I got a Tormach 1100 recently. Inspired by your videos! The problem you're getting with the Y-axis run out isn't because of the tramming. I'm not a fan of twisting the bed to correct for spindle sweep tramming.
It's the head/spindle alignment with the column. If you have a precision pin that's big and long enough (about 0.5" diameter and 4/5" in length), you can chuck that up the spindle with an R8 collet and use your test indicator to measure the misalignment along the X-axis and Y-axis as the head travels up and down on the column.
Assuming that your table movement is square to the head. Fixing this misalignment will resolve that problem. This is something I learned while squaring up the machine. Hopefully this helps!
when you google it the second hit is a NYCCNC video of john demonstrating the RDM
I really like your "warts & all" videos John. We all make mistakes, we kick our own arse around the workshop then we cut another piece of stock and start again. Keep it up, I've learnt so much from your videos.
John, I think you're at the point you need to start making jigs and fixtures for some of the jobs you get and do everything on CNC. That housing is one of them.
That jig or fixture need to be mobile, what I mean is that fixture starts on the Tormach or Haas mill and can be transferred to the lathe or your Tormach lathe. That way you don’t compound errors by using a four jaw chuck. That’s one way !
The other and proper option in your case was to start in reverse. You put the bloc on the lathe, center the bloc, face, and drill the big hole and stop there !
Once that’s done you have your reference face and hole. Now you can use that face on the mill vise and hole to center that part and finish the part from the other side.
The lathe was definitely the right choice as opposed to long endmills. Even using a stout 1.25" endmill you are going to see significant taper at the bottom of the hole and surface finish won't be as good as the lathe can produce. However, you have to be certain your lathe is properly leveled to ensure it doesn't turn a taper itself. Our Mazak at work turns about .0005" taper per inch which can be a pain to dial out when turning anything over a few inches in length.
Hi my name is Dave Cortvriend. Im from Waterloo Ontario Canada. I started My career as a machinist in 1982. I try to avoid drilling pilot holes whenever possible.When drilling large diameter holes on CNC machines I like to use straight shank through coolant spade or index carbide tip drills. But if I have to drill a large diameter hole on a manual lathe with a morse taper in the tailstock I have to use a big HSS twist drill. In that case I drill a single pilot hole as close as possible in diameter to the width of the web of the large drill. Then follow through with the big drill. Example, if the web of a 1.5 inch drill is .2 inches, I use a number 7 drill for My pilot hole, then drill with the 1.5 twistdrill. As long as the drills are properly sharpened it makes a good hole. The entire length of the cutting edge of the big drill engages the material providing good cutting action and chip evacuation, without chipping the cutting edges of the drill, or wearing off the O.D. of the drill especially in harder material, and it saves time compared to drilling multiple holes. The shop I work in has a Darex drill sharpener. It is easy to use and sharpens twistdrills center and spotdrills and can be adjusted between 60 to 135 degrees. Worth its weight in gold!
Reading the comments it sounds like the customer was OK with the part despite being out of tolerance so that is great. Thanks for the upload just reading the comments there are many good observations and suggestions as to why the part ended up the way it did. Great info. Maybe a followup video?
Manual has become underrated, I find this incredible when so many "machinists", do not have a clue about the basics of practical machining.
the bloke was out by 6 and a half thou, I would of been called a butcher if I did that as a second year apprentice and been forced to wear the throw away as a neck piece. But running a business and missing out on that much.....
Kenny I used to do that to my employees, when their necklace got to heavy for them it was time for them to find another job.
Good one John. I am amazed at how you can spend so much time sharing on the Tube while building and taking care of business.
As a maintenance fitter I get to use nice old worn out lathes to hit a tite tolerance it normally involves the dreaded emery cloth. Loving the new video style John.
Mr sheen which is a furniture polish is awesome to use on your granite plate, reason is , it gives a little slip across your surface so you reduce ghost measurements.( Minor ripples in movement from surface imperfections) that cause false drop gauge readings , especially when your in the 0.002 +/- 0.001 ranges .
Also don't for get to mark and date your granite plates corners so you know when to rotate it , you'll notice a shallow will form after running machined parts back and forth over time, simple trick to maximising plate life before calibration and or replacement.
My old plate was 1200mm x 1200mm x 300mm thick. Yup she was thick.
(Aviation sector )
John, may I suggest that if you do some thing like this in future that you rough the bore out in the lathe leaving 0.008" to 0.010" the finish it with a boring head in the Haas. But when you clamp it in the vice only the lightest of pressure. Also when checking the bore on your height gauge rotate the part 90 degrees to check for ovality of the bore.
Interesting observation with forklift driving by! Here in Budapest at the university they have a precise lathe anchored in the rock of a hillside!
TLDR version: You're awesome, John!
Long-winded version: I so appreciate the effort you put into taking your viewers through the honest story of each project - the good, the bad, and the ugly. I can identify!
I started scrolling through comments and it struck me how constructive and intellectually engaged your audience is (generally) compared to other technical or scientific forums. I really think that your style of showing your mistakes, getting your questions out in the open, and not feeling like you've got to have all the answers really disarms those with the usual rif-raf and keeps the comments meaningful and worth reading. I learn stuff every time - not only from the video, but the comments too. There are some sharp tools in this drawer;)
My two cents: I agree about the extrusion faces. When you were running the dial in Z on the mill, I was a little scared. In my limited experience, extrusions are not not only out-of-square, but the faces are also wavy, and doubly so across the grain. If you had happened to run the dial at a different Y on that vertical face, the indicator may have told a totally different story...
Thanks for always showing the whole video makes us all feel more like humans. That fly cutter could've been a bad one.
John, One way to square the end of a part without indicating. Put the part horizontal in the vise take a end mill and make skim cut about a half inch down (with the side of the end mill) on one end just enough to clean up in the Y axis. Now take the part out and put it vertically in the vise on a short parallel (or a small rod) on that cut. Face the end of the part it should be square to the sides now.
I'm going to have to try that.
Bill, Try also when clamping a part that is narrower than the width of the jaws to center it in the vise, if possible. I know there have been many videos showing there is minimal error but this racks the moving jaw and puts all the pressure on one side of the rear solid jaw(run a indicator down the solid jaw after clamping a part this way you will see). This has two negative effects. One you are only holding the part with a point contact on the edge nearest the centerline of the vise (This can lead to the part moving in the vise). Two in the case of my above procedure it can make the skim cut with the side of the end mill not as square to the other side of the part. Using a screwy ball as John did in this video can minimize this and help with One but the case of Two the rear jaw of your vise isn't a solid as you think (depending in how tight you clamp the vise). If you want a part square to +- .001" no big deal but if you want closer tolerances you have to pay attention to everything.
John
One source of the error on the bore size could be that it was distorted from the 4 jaw chuck after you drilled it out . with the metal removed the part might have flexed in and after boring when you removed it from the lathe it sprang back. So you may have a 4 lobbed hole, one way to check it is to place the part at 45° in a v-block and check the size again. If it differs from the original measurement then thats your problem.
If not then you need to do some checking and alignment on the lathe.
Have fun :-)
James
Thanks for sharing the wins and the losses. 🤘🍻🙏
Your honesty is so refreshing John. Ciao, Marco.
Hi John thanks for the video we can learn a lot from your errors and that makes us all think about our work and the order that you have to do things to keep the tolerances good.
Hi John
I would have started at the lathe first.set the material by dial the centre point of the flat sides both at the jaws and at other end.
Drill the large hole out to a rough bore then recheck the material it would have moved from the loading of the large drill.
Bore to the final size the deflection of the boring bar should be smaller at the chuck. Face the part so the bore and one face are dead to each other
Mill the sides next checking thickness to bore
Setup to mill the length in the mill with one edge so you can mic the length
Even raise it on parallels so you can mic the length of the at each side
Then do your drilled holes and counter bores
Graham t Cairns Australia
I know this was posted four months ago and I'm seeing a lot of suggestions in the comments for what probably caused the taper in the bore but I haven't seen anybody mention that you probably gripped it a little too tight, I used to machine pumps and some of the parts inside the pumps were cylinders with two bores inside that overlapped like a number 8 but slightly more overlapping, we'd put them in the mill because they weren't in the centre of the part. Anyway we were having problems with the efficiency of them for weeks because there would be a taper through the bores and we couldn't work out why, using various tools, various tool paths but we never looked at the work holding because it gripped all the part on the outside, it had never been a problem before. Well I'd started going to the gym and was cranking on the chuck key the same way I always had which was resulting in it being gripped way too tight, so as the bore got bigger and the wall thickness reduced as it cut, it'd start cutting bigger and bigger towards the bottom. Lesson learned, it was a torque wrench from then on.
like the trick with dead center , but always indicate all 4 sides on independent 4 jaw chuck , it is still a pretty piece of work
I've noticed that with deep bores in Aluminum that heat is a factor. As you get deeper in the bore the heat build up expands the material causing it to cut more material at the far end. Shallow cuts for the last 30 thou, and cool down between cuts. Or flood cool the heck out of it.
1 video 100 good tipps... always worth my time
I know that sticker on the aluminum... I see you also shop at McMaster! Love that place even if it gets a little pricey, but you can't beat their speed.
really cool idea Adam and thanks for sharing John. so much to learn man
and yes. a quick follow up on what solution you ultimately came up with would be awesome.
Did you level and align that lathe? Looks like beside the bore being out .005" on parallel to the side it is tapered .006" as well. It could also be your jaws are not gripping flat well and tool pressure is delecting the part so you end up small on the outside where it can push off and big on the inside where the chuck keeps it from getting away. Another, and the most likely possibility is you used Abom torque to tighten the part. Being aluminum it deflects very easy. I intend to discuss just this problem in my seminar. I bet the jaws had the bore squeezed so after you released it from the chuck it expanded and went oversize. You are measureing in the same plane as the jaws applied pressure. Would be neat to rotate it 45deg and measure again and see if there is variance in the bore dimension, I bet there is. That would prove an out of round condition caused by the jaw clamping forces.
bcbloc02 ...,agree with your assessment I have to realign my manual lathe every 4 weeks to compensate for the floor moving, weather changes, and if I do a lot of heavy cutting it slowly moves out of tolerance. I tend to be very picky about it but I’m accounting for tool deflection and outside parameters that can additionally cause a part to go out of spec and I’ve learned to rely on keeping it dialed in even if my parts tolerance isn’t .0005 it’s a matter of it being reliable between jobs.
John, good looking part but the bore tolerance problem might be cause by head stock alignment issues. Set up of is so important in any tool. Level the lathe then align the head stock. Not only does this alignment affect turning along the z axis it also comes into play while facing off surfaces. We want them flat not shallow dishes or cones depending which way the head stock is swung.
Totally agree with the method. Long endmills will deflect more than this setup (is my guess!) so this should be the easiest way of making large deep holes.
More than likely it's the clamping pressure on the lathe that caused the problem as you have to really grab things with supper even force as the normal lathe jaws put a pressure point on the material which can make it out of round and mess up the tolerances. You would have to make some soft jaws for the lathe with a lot more contact surface area to correct that. That is something I learned from Haas, Thanks Haas :-).
i just recently bought some 3 in 1 jaws from Kurt and they are super handy for squaring up stock without having 3 hands. I'm sure you could make some up for the orange vise.
and on the hole, i would have just u drilled to near size and bored (either boring head in the mill or if i was doing it in the lathe use the same u drill)
John... As allways a pleasure watching you work! Thanks buddy! :)
I love that trick (double center)... and it's great to see you use a manual machine. :)
When measuring that bore with the height gage you really should have some parallels and gauge blocks to keep the part square to the machine and slide the part against the gauge to avoid error.
I think its most likely lathe run out. Had a similar problem on my lathe at home...you tram it basically the same as your cnc. I did mine with the starret level I have now its within a thou...but as you said all sorts of stuff can put it out again when you use packing under the lathe to get it trammed correctly. Its something that we should all be aware of but the daily grind makes you complacent
Sq. the 4 sides on the Tormach or mill, place in lathe, face one end, brill and boar center hole, flip and face other end then drill remaining holes on the Tormach.
I like the new music.
Check out noga mini reversible debur tool, amazing tool and replaceable blades with an Allen key hidden in the handle. It will blow your mind.
Part in center of vise is best. If you put a 3/16" piece of round shaft under part, by solid jaw, and clamp part on movable jaw using a round shaft too, it works great for initial square cuts
Late to the game, but for cost effective use, and replacing inserts instead of sharpening, U-Drills work awesome. Beats sharpening steel.
You did it pretty much how i would do it. another way to do it is get round stock and do the bore on lathe first then mill the square out. more work that way though.
Trial and error machining. Take a deep breath before taking a cut. That amount of time may help to prevent a mistake. All the best.
nice job on that john ! came out better than my parts lol
have you ever checked the deflection on the fixed jaw of your vises? it could surprise you.
my Kurt 688 will deflect about .001"/10f/tlbs of torque. the resulting pressure applied is +/- 1000lbs of clamping force per 10 ft lbs. If you tighten to the maximum recommended torque of 40 ft/lbs you can easily get 3 or 4 thoul error.
With that kind of load the bolts holding the fixed Jaw stretch and deform. I know that Orange makes great vises, as good as Kurt does, that's not to say that they don't have inherent design faults.
My second Kurt, the 3600V, is a mono block design and showed 0 (zero) deflection at maximum torque.
just some food for thought.
Also i know diddly squat about CNC but i might of squared the block to size prior to setting it up in the 4 jaw, the face run out might of been an indication that something was off somewhat. (or facing off the part once in the lathe might of helped.)
Love your video's and great fusion 360 tutorials
Thanks John
You are absolutely correct about the Kurt Vises. We have had the same issues, and only use the Kurt 3600 when we are looking for close tolerances. We also use the torque handle if we need repeatable positioning. That helps keep things as consistent as possible especially with small parts, or parts that may have some flex.
I was surprised when i tested the 688, its not a bad vise by any means, but one needs to be aware of its limitations.I also use a tq wrench if I'm doing multiple parts to tight tolerances.
cheers mate (subed btw)
If you want to try for an accurate thru hole you could always drill at 0.030" smaller than final, circle interpolate leaving 0.010 stock (as deep as the tool can possibly go), then ream. The reamer should follow the circle interpolated hole nice and easy. Flip it over and repeat. I know that a reamed hole is not a requirement but the method I outlined does make for an accurate hole.
You might want to check the lathe for "square", as one of my favorite teachers told me. You can run a lathe on a ship, which means you don't need to have it level all the time. You need to have it square. Try "rollies daddies method" of squaring the lathe and you should get a straighter cut.
John, I think that the head of your lathe is not parallel with your bed. Many lathes have adjustments to let you tweak that. The other possibility is that the ways are worn unevenly near the chuck.
love the edit flow of this video .
About the runout on the lathe, I think you might have corrected the far end of the part with the center but left the chuck side as-is. That may also be the reason why you measured a runout on the face of the part when you had it in the lathe. That explains the conical hole. (it should not have any runout on the face, because you showed on the heightgauge it was actually nicely parallel to the opposide side.)
Liking the new style, man! I noticed the little things ;) great work as always!
All that fantastic equipment and a sink that looks like you pulled out the local canal !
Only joking, great work :)
You can do this job in two installs.
Milling - processing of the maximum detail
for 1 installation, and here you suffer with something like 5-6 installations, so there are many shortcomings in your activity
john a bored hole should be straight regardless of the alignment of the part to the centerline of the lathe. the hole may end up off center but not oversize. on one end. your lathe may be worn or out of alignment try boring a similar hole in round stock and check for oversize. if the problem is the lathe it should show up with any chuck or material configuration. the problem should also show up on od turning..the accuracy capabilities of those big ridged cnc machines can really spoil you.
as the bore got bigger the walls got thinner. releasing preasure on jaws some would help before finish cut. just like on the grinder when the magnet is turned down it would be true
I would have loved to see you measure the True position of the bored hole. Since you faced the sides of the part after boring the hole, there was nothing holding the hole at centerline except the assumption that it was perpendicular to the top face.
Great video. Enjoyed watching and learned a thing or two.
When I drill big holes on the lathe (1" +) I put a lathe dog on the round shank of the drill and rest it against the compound rest. That will keep the drill from spinning in the taper.
short hole drills with inserts would be great for that big hole.
I'd bore and face to length on the lathe, maybe on an arbor, bolt down the center on the mill and you could square the outside while you do the holes. Or square the entire block before you bore the hole. I would mostly keep the flip flop between machines down and make sure the bore is perpendicular to one face in the same op.
Pressure on the chuck jaws could have pushed the material in only to be relaxed outside the tolerance upon removal too.
Nice video ! - A lot of the error could be because the block wasn't squared up first. Your K&T could be really handy for this - setup a big facemill in it... You should be able to get excellent finishes with it. I would also check out the chuck and chuck jaws on the lathe and make sure they are all running true. I use a big 1"x6" "dowel pin" purchased from McMaster for $15 as an inexpensive test bar.
Thanks for sharing
You could do a lot worse than pick up a tool and cutter grinder. I have an old Clarkson one that makes a brilliant job of sharpening drills and cutters. I have also used it to make custom cutters for specific jobs. Its a skill in itself to really learn it but oh so worth it.
If you were off on your the face of your part when you were dialing it in with the dead center, than the back side of the bore would show this as well. This could be the source of your run out on the backside of the bored hole.
Another tip for you, why struggle so much to achieve these tight tolerances? Recommend a jig grinder
I recommend boring head in the mill. I think you blew your tolerance by not indicating the part square to the face of the chuck. You got the center hole on center, but you may have had a wobble in the part, leading to a bellmouth at the rear face (chuck facing side) of the part.
Hi John,
your videos are great, love them
did you occasionally check your headstock alignment?
I have the CNC version of the EMCO V13 and had to align my headstock recently because parts turned out to be tapered.
The V13 has good possibilities to align the headstock, however it is a quite anoying work
You need to start auctioning off all your goofed parts like they do with crashes and blown parts at the drag strip. lol Would be fun to get a few. :)
Why would you bother clocking up a stock face when you were squaring up, surely a stock face would never be good? Plus spend time on learning to grind drills, so worth the time spent into it, especially for a machinist
If you have through coolant use a udrill depending on what drill feeds and speeds a good place to start is 0.1mm / rev and 150 metres a minute on spindle speed
Hey, your first video without a crash. -:))
Congrat. :)))
like the new style John - keep up the good work
this video really reminds me of the how to square a stock from this old tony xD
With regard to the comments that exist for no reason other to make fun of him: I wouldn't be too hard on him. We need young guys in the trade. Constructive criticism to educate him, rather than just poke fun at things he doesn't know would be more helpful. Before we're all dead and there is nobody left to teach the ways of the trade. With that being said, were you using dino to cut AL?
High pressure coolant through insert drill.
HSS 1.25 6fl. End mill spiral down through.
HSS is cheap and is good for aluminum.
Why did you mill the outside last? Had you squared up the entire block first, you probably wouldn't have scraped it.
Hey John, you mentioned in your podcast that you learned a lot about tramming your Tormach at the scraping class. Think you'll do a video about what you learned? Thanks, Love your channel!
Liking the new video style, they seem to be faster paced with more interaction. Very nice. However, it appeared a little washed out. Perhaps color correction could help it? Maybe I'm just seeing things considering its 1:30 in the morning.
7:10 when you measure machined surface in X axis which was machined in X direction, there will of course be no difference. When you measure it in Y direction, you see how much is your spindle out of squarness compared to Y rails. And 0.001inch - 0.02mm on such short distance is a lot. If you would run 80mm face mill on 160mm wide part, your error between two passes would be dobule, so 0.04mm edge.
Your place is like candyland
on my work we have a small machine where you mount the drill in a clamp and just rotate it by hand and it sharpens the drill, works verry well, verry smooth. maybe you should look into that verry cheap machine i think my boss payed 400 euros for it we have one for small and big diameters
Nice height gauge!! And come on John! You know you need to square the block on all sides first!! Awesome video though, - Jacob S.
Hiya nycnc......sorry if missed the link...the internal deburring tool, noga.? Or who,s make it is...can you add link again....looks like I could use one...or any viewers..cheers Pete
Enjoyed John!
ATB, Robin
very high quality video thanks for this
You cannot bore on a manual with such a long tool and expect there to be no run out, I believe that was the problem with it.
Also 4/1000th of an inch isn't such a bad tolerance if you are doing it on an manual with no experience, great job!
If your bore was oversized only on the side of your chuck jaws. It was probably the jaws pressure on the thin wall the problem. You should check if your bore is round. I'm pretty sure the hole is oversized only on the 4 contact point of the jaws. I know a guy who know another guy that make that mistake ;)
Johnnnn....howww do you feel having more than oneee CNC lathe? hehehe..
Man, God bless you everyday Sr....for your hard work.
Personally i would just have plunged the boring bar from the first drill take a wide pass.. it works great if you are going straight thru and most inserts handle it easy..
Cool project!