Thread: Your latest project

Originally Posted by Jayson

So inspired by what RC got himself around this time last year I decided to make my own

Attachment 246733

A brand new 5mm endmill turned into 2 bits of scrap HSS in a fraction of a second.

Just for future reference 1500 mm/min 15 mm deep at 1500 rpm is not the correct feed rate to cut a hold down bolt in half...

I was able to find another endmill though and got this done:

Attachment 246734Attachment 246735

It is the beginnings of a 45:1 Hypocycloid gearbox. It is 45mm across and 12mm thick made from an off cut of hydraulic cylinder ram which I believe may be 4140 steel.

Jayson.

Hey Jayson,

Any chance of expanding a bit on how you machined the part? Looks tricky. Looks good!

Bob.

Originally Posted by Anorak Bob

Hey Jayson,

Any chance of expanding a bit on how you machined the part? Looks tricky. Looks good!

Bob.

I was going to ask as well. A rotary table and some indexing ? I am only guessing

Hi Bob , morrisman,

Well I guess I cheated a bit, I used my Beaver VBRP that I've been converting to CNC for quite a while.
Its only early days with this mill running so I'm putting it through its paces to see what does and doesn't work.

I ruined the part today after trying to re-machine it it take off a little extra material so I'll make another tomorrow and take a few pics of the processes involved in making it if you like.


Jayson.

Originally Posted by Jayson

I ruined the part today after trying to re-machine it it take off a little extra material so I'll make another tomorrow and take a few pics of the processes involved in making it if you like.


Jayson.

Yes , lots of

OK here you go.

This took a lot more out of the day than I expected it would as after investigating a little I found that I had not trammed the mill very well before making the previous parts

Needless to say I had to do that before I did this.

This one was made from mild steel instead of the 4140 simply because It was there and I did not have to cut another slice off the hydraulic ram.

The raw material was around 52mm diameter and looked like this

KICX2546.jpg

The first thing I did with this was took it over to the lathe and roughed it out to save on milling time.
The blank had a step on the back that would need to be faced off later but I could use it to hold on to the part for the initial roughing process. I wanted to turn the outside dimension to 44mm but that meant machining up to the chuck jaws so I used a few pieces of steel packing tape to space the blank out from the jaws by 0.5mm (I removed the packers once the jaws were tight) I then machined the outer dimensions and bored the hole in the center. I went smaller on the center hole this time to match some bearings I had just found.
Once bored I turned the stock around in the chuck and faced off the back

KICX2549.jpgKICX2551.jpgKICX2553.jpgKICX2554.jpg

With the blank ready to machine I got to work setting up the next step. I took a couple of scrap pieces of perspex sheet and drilled a hole in each piece at roughly the center.

KICX2557.jpg

I then positioned these on a simple fixture plate I have made from 6mm steel that has a 10mm hole tapped in the center of it. I place piece of rod in place of the cutter and position it over a T slot and lined everything up as close as possible and clamp in place.

KICX2558.jpg

Then using a 5mm 2 flute end mill I machined a 1mm deep pocket slightly larger than the outside dimension of my part. The tolerance was good enough that it was a press fit into the pocket. A bolt then goes through the stock and into the fixture plate, tightened very well to prevent any @#$%$#!!! later on. I also checked this time to make sure the cutter would not hit the head of the bolt.

KICX2560.jpgKICX2563.jpg

Then it was simply a matter of turning on the mill and letting it do its thing

KICX2564.jpgKICX2568.jpgKICX2570.jpg

Those of you who are paying attention to the photos will notice that in the last 2 photos there are some cutter marks leading up to a clamp, lets just say it got very close to @#$%$#!!! since this was a clean up cut at the end of proceedings. I wasn't watching the clock but I would say this was at about 45 minutes in.

Once removed from the mill there was a small burr on the upper surfaces so I turned up a short piece of shaft and pressed on the part, taking a very light cut removing very little material apart from the burr.

KICX2575.jpgKICX2573.jpg

Once this was complete I pulled the part off and took some measurements The part was as close to perfect as I could expect at this stage.

KICX2580.jpg

Here is a short boring video of the last cleanup cut.



I have no idea why the mill sounds so bad as it really does run quiet in real life.

That's it for now,

Jayson.

Thanks for taking the time to post the report , impressive

Neat Jayson,

I dare say machining that sans CNC would be a challenge. It has me stumped but that's easy because I'm a Luddite. I wonder how it would have been done, a copy mill or pantograph?

Bob.

Hi Jayson,

Good to see the Beaver running

I especially like the custom keypad, very slick.

What is the part used for, oil pump maybe?

Regards
Ray

Thanks Ray,

The keypad is working well. I am having some issues with the touchscreen though but am still able to use the mill with the keypad and an occasional keyboard input.

I am attempting to build a gearbox similar to this Hypocycloid Gear Reduction

Mine will be 45:1 and I hope to put it on the knee of the mill. If not at least it will make a great conversation piece for the desk.

Jayson.

Hi Micheal,
Brave man, well done. Have you fixed the Volstro head yet?

Hi Jayson,
Interesting project. Great looking mill
Knowing almost nothing about CNC milling, 45 minutes seems like a long time, what am I missing?


Stuart

Working on it Stuart.
It's on the list with around a dozen other things (plus requests from others). I run out of leave on 7th, so it's a race. The two things that I need to do are devise a mount to fit the register and work out how to get the drive through. It has an R8 fitting and the original instructions were to lower the quill to enable the arbor to be engaged, then raise to allow the register to engage. Not having a quill and an ISO40 spindle means another way is needed.
The mount is (relatively) easy and I'm working on that at the moment. It's the drive that I haven't finalised my thoughts on yet.

Looking at Jayson's hypocycloid drive, I think that the Volstro could almost machine one of them...

Michael

Originally Posted by Stustoys

Hi Micheal,
Brave man, well done. Have you fixed the Volstro head yet?

Stuart

I'll second Stu's first comment Michael. I don't reckon I could stone up enough to turn the 13 on itself.

I'm keen to see the Volstro working wonders when it's saddled up. I'll hound you for photos.

BT

Hi Stuart,

45 minutes is a long time, I think it is a combination of the 5mm cheap end mills and my experimentation of what I can get away with. I have 4 broken cutters to testify to what does not work and only one usable left at the moment so that factored into things as well.

Sure is quicker than with a file though

Michael, I am happy to send you over the drawings if you want to have a go at one...

Jayson.

Hi Jayson,
I only say "a long time" as I worry about rubbing rather than cutting if the cuts are to light.
Please tell me your 45:1 is a typo? I've been trying to get my head around these things and cant match the 100:1 one you linked to to your 45:1. The best I can get is 56:1
His other video helped me see what was really going on.
Hypocycloid reducer, 100:1, Internal view - YouTube

Hi Micheal,
Hope the list gets a little shorter by the 7th...... unlike my list lol

Stuart

Stirred into action by Stuart's comment I did a little bit more today. All I need to do now is do a little welding, drilling and tapping and I'll be ready for a trial run in the next day or so. There will be photos.
I must admit to feeling a bit nervous about machining the vertical head. Although I could reason that seals and bearings are round and so minimum clean up would not be doing any damage, translation into reality was harder to do. I only took the opportunity as the head was off for repacking with grease. One of those now or never moments. It does surprise me though - this mill is a well featured universal mill but the makers never thought that a register surface on the head may turn out useful - even if only as an indicator mount.

Michael