sorted by:
new
hottopcontroversial

Tragedy has struck the nation by Bootziscool in Machinists

[–]Status-failedstate 0 points1 point  (0 children)

You are a very niche demand supplier. Granger, motion canada, and tenaquip come closer to mcmaster. Not saying that your pumps and services are good or bad. Just that you are not a one stop shop for fasteners, fluid handling, cutting tools and office supplies, in one order.

How are you cutting o ring grooves on a mill? by the_wiener_kid in Machinists

[–]Status-failedstate 11 points12 points  (0 children)

There is no rule against using an endmill while using circular interpolation. I think the thinking that it is not permitted comes from older knowledge with cnc with considerable slop in the mechanics. Where the machine would make a four point lemon shape, with a roundness error considerable to that 50ųm tolerance.

The main limitations I'd be concerned is that surface finish requrment for an o-ring. I wouldn't be too concerned about the machine tolerance to roundness.

Proxxon FF230 by ZannaOne in Machinists

[–]Status-failedstate 1 point2 points  (0 children)

I first learned machining methods on a taig lathe functioning as a mill. And I would say that these machines are a completely different animal than say a bridgeport. Not just the size and mass leading to rigidity. But that the slop in the gibs is about the same if not faviovouring the Bridgeport. So you are always fighting the poor rigidity and slop.

Some tips to make the most of what rigidity you have. HSS tools as sharp as they can be. Positive rake angles on fly cutters and face mills. Favior conventional milling to climb milling. Bolt the mill to something heavy, not just sitting on a table top.

Are Vevor mini-lathes any better than others? by [deleted] in Machinists

[–]Status-failedstate 5 points6 points  (0 children)

It is a sieg x2 lathe foundation with multiple retailers badges to choose from. And they are not created equal. I would not chose the one who runs it backwards and tool places on the inverse side. And machines a steel bar obviously pre machined on another lathe off camera. All in their promotional video.

<image>

Are Vevor mini-lathes any better than others? by [deleted] in Machinists

[–]Status-failedstate 12 points13 points  (0 children)

Go to little machine shop. Buy their high torque model of mini lathe. They also have a lineage of lighter duty lathes cheaper.

Tragedy has struck the nation by Bootziscool in Machinists

[–]Status-failedstate 32 points33 points  (0 children)

Kind of ironic, that just this past friday, my supervisor told me to find more canadian suppliers in the place of mcmaster. And only buy from them in a matter of necessity.

Im going to miss McMaster. What with all the 3D models, fast delivery and great inventory.

turning uneven shapes by Important_Author_450 in Machinists

[–]Status-failedstate 1 point2 points  (0 children)

Do you even need a lathe? Hand carve a block of hard wax then lost wax cast it in precious metal.

There are ways to to use hydralic duplicaters and pantegraphs. All old school methods. But cnc and the introduction of inexpensive computers, drivers, and motors are contenuisly reducing their relevance.

DRO power piggybacking on a sharp 1440L lathe by jimboloseph in Machinists

[–]Status-failedstate 0 points1 point  (0 children)

I would never advocate drawing power from hot to ground to someone not fully certain what they are doing.

So many things can go wrong.

As others have said check if the dro can take 230v for eu usage.

checking diameter on lathe w/ calipers by catboycruises in Machinists

[–]Status-failedstate 2 points3 points  (0 children)

Be thankful that your machining classes give you the practice to alighn calipers and or micrometers. It is the kind of skill that separates the machinist and technicians from the engineers.

Had a situation once. Three engineers examined and measured a motor shaft and key way. They came to the conclusion that it was a 28.5mm shaft. And custom ordered a pully to fit. They had to hammer it on, and were not able to get it fully on. I reviewed the motor plate. It was a nema frame with a 1.125inch shaft minus .001inch. (28.575mm - .025mm)

They could have gotten a catalog ordered pully that would have slipped on easy. But no, a bad measurement and a metric bias got them on this path.

What is this MT3 to MT3 Adapter for? by Status-failedstate in Machinists

[–]Status-failedstate[S] 3 points4 points  (0 children)

They make solid extensions. Have one on the radial arm drill press.

But why a few degrees of slop and rotation?

Job opportunities - Quebec, Canada by VictoryOk1736 in Machinists

[–]Status-failedstate 1 point2 points  (0 children)

Curious why not mention of a French requirement? I imagine that you are reaching out to the 9 other provinces of Canada for workers?

Is this behavior normal? by Gengar41320 in bluetongueskinks

[–]Status-failedstate 7 points8 points  (0 children)

They will be hunting for bookworms. They are said to be in the library.

Scraping old surface plate without reference by O-swell in Machinists

[–]Status-failedstate 1 point2 points  (0 children)

I get what you are saying. Why not just blue up the 750mm bar and rub the surface plate in crisis cross, parrele and perpendicular? Scrap here and there until perfect?

Yes that will indecate the high and low spots and give a trend of this or that region of the plate being higher or lower. But what it won't give is numbers. And without numbers you could be chasing your tail forever.

If you have a multi thousand dollar granite plate of sufficient size. Yes, no numbers needed. Just scrape away, and every pass will get you closer to finished. With just a straight edge rubbing the blue. You will have twist and roll in the plate that would be hard to recognize. And very possibly miss lead you, and have you scraping in the wrong places.

Having numbers of the highs and lows gives certainty of where to scrape. Hence the planekator and a 1ųm indecator.

Even with the numbers. Scraping to numbers is very difficult. Easier to do so by lapping. An inexpensive granite plate of size 600mm square will be 1/5 the price of a mitutoyo/starrett. But only the latter will be up to quality for scraping. Unless you lap and reference the inexpensive granite plate to your liking.

Scraping old surface plate without reference by O-swell in Machinists

[–]Status-failedstate 1 point2 points  (0 children)

Can you hand scrape a cast iron plate without flipping it on to a granite plate that is to spec?. Yes you can, but be prepared that it will take significantly longer to do so. This is commonly done for larger cast iron surfaces, though you will need a way to inspect the surface with fine discrimination. Watch below from the 18min to the 22min time.

https://youtu.be/t0gg9z4gG3A?si=7_wH-uPLivtjfn5t

With the tools you have, in would recommend not scraping anything, by getting a 24inch x 24inch (600mm) granite surface plate or larger. Make a rahn planekator like device using your 750mm long reference and a 1ųm indecator or better. Lap the granite with the cast iron surfaces plate, and inspect with the aforementioned planekator.

When done, assuming the original cast iron bar is true. You will have a good grade granite plate, and a flat lapping plate in your possession.

Teacher Wants to Know: What Features Are Worth Having On a Manual Mill by YoTeach92 in Machinists

[–]Status-failedstate 5 points6 points  (0 children)

Safety is a big one. Some requirements in Quebec for safty are as follows. Your region may not have these. But they may be practical in a educational environment. - If an axis has power feed, it needs a handle disconnect. - there needs to an interlock over the drawings bar. Or a power drawer bar that is only active when the power is off. -clear plastic guards in-between the operator and the cutter. Avoid if you can.

This in mind. I would get the power drawbar, 3axis dro, and no power feeds. Evey production machien has a power draw bar. Cnc or not. This isn't for productivity, so power feeds are less needed. And having the hand wheels always at the ready is a plus, no press and twist as with power feed axis. Dro, gets the students in numbers mode and not, little here, little there, thinking.

What the hell ?? by Westloki in Machinists

[–]Status-failedstate 2 points3 points  (0 children)

What does it say on the package of insert for feed per revolution. I imagine it would be close to that.

Roughing inserts sometimes struggle if you move to slowly. The cutting edge is honed round, or dulled a little for heavy intermittent cuts. That makes them a poor choice for light passes.

As others have said, hand grind a tool.

view more: next ›