Todays Project - What did you do today?

[PixMan]

Spent about 6 hours in the shop, finished the 3rd go-around on the quill feed trip bracket part for Darren's Kondia milling machine.

Typical of a part with so many operations and features to machine, two little mistakes. Neither will affect it's function, fortunately, but minor cosmetic blemishes.

Here's a shot of the 3 parts. From left to right, my first (2nd actually, never got beyond the first setup with the first before finding a fatal mistake.) In the middle is the one I finished today. You can see one of the "oops" as a slight overcut on the Ø38mm counterbore where the machine was giving me fits with error codes as it went to the first (plunge) position for the circular milling. The first position looked correct, but it alarmed out with a Y axis error. I had already plunged the center-cutting Ø1/2" 4-flute solid carbide end mill before I noticed. The other error is hard to see in the top view. I had miscalculated the depth of the surface with the Ø5mm pivot pin hole is located. I drove over to my friend Jennifer who TIG welded the surface back up so it would clean at the correct height. Very little evidence of my screw-up, thanks Jenn! On the right is the original part from the machine. It's probably hard to see in the photo, but the counterbored holes for the M6x1 mounting screws are 2mm higher and 1mm further apart from those on the part on the leftm which was made to the print sent to Darren by Kondia. The new(est) part is also overall 1mm wider than the one on the left.



I will try to ship it out to Darren tomorrow, but it may be Wednesday at the rate I'm going. Darren, do you want either or both of the junk parts sent?

[Mayhem]

I don't see any blemishes, only character and a damn fine part that I would be screwed without. Please thank Jennifer for me for her assistance. I don't need the other two parts to be shipped back, just the new one and the plunger. If I decide I cannot live without the others, I can toss them into my suitcase next month!

Thanks again Ken - I really do appreciate your help

[vtsteam]

Broke the clutch pedal on my '51 John Deere Model M, so spent the day fixing it.

The pedal was getting difficult to push and worse to release because there's no obvious way to lubricate it. It pivots on a keyed sleeve over a shaft that connects the left split brake pedal to a control arm on the left side of the tractor. The brake shaft and clutch sleeve rusted to each other, and both tended to operate at the same time. You can't easily remove the shaft because it is conected to the throw out arm inside the transmission.

I didn't realize there was a key in the sleeve. The clutch pedal has a slit and pinch bolt attachment, and I had removed the bolt and tried to rotate the pedal out of the way -- hardly used any pressure, but the casting broke because of the key. The iron was only 1/8" thick at the corner of the key slot, and that's where it broke. What a bummer!

Since I also couldn't get the shaft out, and a brake control arm was pressed onto the end of the shaft outboard of the clutch pedal sleeve, there was no way to repair the old pedal by brazing or welding, because I couldn't then slide it back on. Also I didn't like how little metal there would be in a repair. I was really surprised how little metal was actually holding that thing together. Frankly I would rather lose brakes on a tractor, than suddenly lose the clutch pedal! That could be really nasty.

Finally I decided to make a new part -- kind of like the big end on a connecting rod -- with a cap held on by 2 bolts, and a keyway. That way I could clamp it back over the shaft. And it would be removable for getting lubrication in the key slot so the clutch sleeve wouldn't freeze to the brake shaft again.

So spent the day machining it out of a substantial square block of steel, bored to fit the the sleeve, split and keyed. I did a lot of trial fits, because there were some clearance problems -- it's a much bigger hub. Finally after grinding clearance where needed, I cut the old hub off of the old brake pedal and welded the pedal and arm to the new hub.

It was nearly dark by the time I was able to drive the tractor back to the house from the field where I had been working. My mother in law, up for a visit said, "Here comes the grease monkey!" I definitely looked the part -- took about a pint of Fast Orange to get ready for dinner.

[PixMan]

(09-01-2014, 07:37 PM)Mayhem Wrote: I don't see any blemishes, only character and a damn fine part that I would be screwed without. Please thank Jennifer for me for her assistance. I don't need the other two parts to be shipped back, just the new one and the plunger. If I decide I cannot live without the others, I can toss them into my suitcase next month!

Thanks again Ken - I really do appreciate your help

Glad to be of help Darren, and SO glad it's done. Here's some close-up photos of the minor defects. Only the one on the front counterbore will be noticeable, and only if using a "critical eye",

[PixMan]

(09-01-2014, 08:10 PM)vtsteam Wrote: ....>>So spent the day machining it out of a substantial square block of steel, bored to fit the the sleeve, split and keyed. I did a lot of trial fits, because there were some clearance problems -- it's a much bigger hub. Finally after grinding clearance where needed, I cut the old hub off of the old brake pedal and welded the pedal and arm to the new hub.

Pics of the repair or it didn't happen!

[awemawson]

Give him a break Ken. He was in a remote field, greased up AND had his mother in law breathing down his neck

I doubt that the camera was his first priority

[Mayhem]

(09-02-2014, 02:48 AM)awemawson Wrote: ...He was in a remote field, greased up AND had his mother in law breathing down his neck ...

I've seen movies on the internet that start like that...

I don't know Andrew, I'd have the camera as a much higher priority than the monster-in-law any day

[Mayhem]

(09-01-2014, 09:18 PM)PixMan Wrote: Glad to be of help Darren, and SO glad it's done. Here's some close-up photos of the minor defects. Only the one on the front counterbore will be noticeable, and only if using a "critical eye".

A coat of paint will cover up the weld and if I ever worry about getting the fine feed hand wheel, I'm sure that will cover the other one.

As I said - at the end of the day it's nothing. In fact, that is not true - it is the lead in to a story of not only the process of bringing this mill back to life, but the friendship born from a web-based forum that has enabled me to get a part made that is no longer available as an off the shelf item. I think you should mill a recess into the flat section through which the 16mm bore runs and stamp your name or initials on it...

In a mass produced world it is nice to have a unique piece. Of all the Kondia mills out there, none will have a feed trip bracket like this one.

[PixMan]

(09-02-2014, 02:48 AM)awemawson Wrote: Give him a break Ken. He was in a remote field, greased up AND had his mother in law breathing down his neck

I doubt that the camera was his first priority

So true, point taken. A shot of the finished product is all I'm hoping for, as a picture speaks a thousand words and I'm curious to see just what it looks like, old part vs. new part. In no way am I pressuring for photos, they're just nice to see.

I often get to working in my shop (as I did with Darren's part) and don't think to stop for "progress photos", or just don't have my little Canon Powershot SD880iS camera with me. One thing I always seem to have at hand though is my idiotphone, and it's got an "ok" camera in it.

(09-02-2014, 06:10 AM)Mayhem Wrote: ...>> I think you should mill a recess into the flat section through which the 16mm bore runs and stamp your name or initials on it...

In a mass produced world it is nice to have a unique piece. Of all the Kondia mills out there, none will have a feed trip bracket like this one.

Thanks, but I'm just barely not that vain. It may mean something to each of us, that's enough. Even years from now an experienced machinist looking at it would recognize that part as being "doesn't look original" and not give it a second thought as long as it's working. The layman "non machinist" wouldn't give it a send look even if it had initials in it. ;)

[vtsteam]

(09-01-2014, 09:21 PM)PixMan Wrote:

(09-01-2014, 08:10 PM)vtsteam Wrote: ....>>So spent the day machining it out of a substantial square block of steel, bored to fit the the sleeve, split and keyed. I did a lot of trial fits, because there were some clearance problems -- it's a much bigger hub. Finally after grinding clearance where needed, I cut the old hub off of the old brake pedal and welded the pedal and arm to the new hub.

Pics of the repair or it didn't happen!

The flat area on the left side is the wall of the key slot. The crumbled section is the cast iron hat was holding the hub together.



What I ended up with:



The stamped part on the outboard end is the control horn for a brake rod. It's pressed on the shaft, so no way to slide on a re-welded hub. The new hub is a cap type with two retaining bolts threaded into the hub and going in opposite directions. The hub is slotted internally for a key and the bore is a close fit to the clutch throw-out sleeve, which rotates on the brake shaft, then the hub was split on the band saw. I used a rusty old chunk of steel from the scrap box -- don't know what kind it was but it was slow machining.