KO-Lee Cutter/Grinder Revamp

[Ray C]

Look what showed-up today. It's very nice and small for a 1HP unit; lightweight too, at only 15 lbs. From the fan housing to the tip of the shaft, its 10" long. I had another motor that could have been used but, it was a 1.5HP heavy service class 2 device and I really did not want to use it for this project. https://www.ebay.com/itm/1-HP-Elect...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

I have not wired it up for a test spin yet. Maybe tomorrow.


Ray

 

[ddickey]

Here's something I use all the time. It's a ram bar that fits in the ram of the tailstock. Make one sometime. They're very handy for this purpose. The SS block is lightly held in the jaws and a couple of parallels between the jaws to prop-up the part. The ram bar does a great job of applying even pressure to hold the piece nice and flat. Of course, it can be pushed by hand but, it's very easy to apply uneven pressure. REMINDER: Remember to remove the parallels before spinning-up the lathe.

When you press on the part by hand, when tightened, the jaws overpower you and the part shifts. This is less likely to happen with the ram bar. I used the ram bar when facing-off both sides of the piece and the width varied within 0.0003" measuring all the way around. You could tap on it with a dead blow hammer but, instincts tell me that the spindle bearings would prefer not to be pounded on.

View attachment 259830
Ray

I tried this today but couldn't get the parallels out after tightening.

 

[Ray C]

I tried this today but couldn't get the parallels out after tightening.

I do not use a lot of force with the ram bar; just enough to hold it firmly. Once the jaws are tightened, I can wiggle them out of there without too much fuss. Similar problems like this arise when using parallels in the mill vise. Eventually, you'll develop a knack for how much pressure needs to be applied. Also, you can try to snug the jaws up firmly (but not tight) then remove the parallels then, give it the final tightening.

One other thing, when I tighten chuck jaws, I do not go ape-man on the t-bar. A quick push of body weight is all it takes. Don't pile-drive it with muscle -not necessary. Firm, yes. Gorilla -no.

If ever you're uncertain about tightness of a part in any jawed fixture, stop your work and check it.

Ray

 

[ddickey]

A little to much force me thinks with the TS ram.
Thanks Ray

 

[Ray C]

A little to much force me thinks with the TS ram.
Thanks Ray

You know what they say... If just enough, is just right; then too much is even better.

Ray

 

[Ray C]

Here's another odds&ends piece of metal now donated to this project. The metal was unmarked and judging by the way it cut, it's almost certainly 1018 or 1117. Couldn't pull a finish out of it to save my life. Anyhow, it was cut very unevenly and just barely the right diameter; also, it was just a little longer than needed. Make lemons out of lemonaide... When it was chucked-up, it was not pressed flat against the backside of the chuck. Instead the piece was positioned to minimize the amount taken off the outer diameter. The front/back was wobbling like crazy but the OD was running evenly.

The OD was skimmed just enough to get past the scale and preserve as much OD as possible. Only had to take off 25 thou. The cut was taken as close to the jaws as I dared go.


The jaws on this chuck are running very true so, the piece was just flipped and the remaining scale was cut off. The OD's of the first and second cuts to remove the scale matched-up remarkably well. I'm loving this new 6 Jaw.

After the OD was trued-up in 2 steps, then finally, the faces were squared-off. This brought the length down right in the ballpark. One side needed this little shoulder to match the pocket in the stainless piece made yesterday.



Here it is sitting in place on top of the stainless steel thingy from yesterday.


Next, I'll attach that carbon steel puck to this piece of mild plate steel which is about 0.75" x 6" x 8". Initially I thought I'd weld the carbon steel puck to the plate but, I'll go with bolts to keep from warping the daylights out of everything. Also, if this project crashes and burns in failure, I'll stand a chance of reusing some of the pieces later on.



I think you get the picture... Some brackets will be made to hold the spindle to the heavy plate. [Not shown: Some other brackets will extend from the plate upward and above the spindle to another plate that will hold the motor. I'll put (TBD) vibration isolators in the upper plate that holds the motor. Oh, BTW, the shaft on the spindle will get trimmed down as soon as the bracket arrangement is worked-out].



At this stage, we're really winging this part of the project because, everything is coming from available shop drops.

Until next time...


Ray

 

[Ray C]

The good news, this is coming along... The bad news, it's coming along at a snail's pace.

The crude housing and motor bracket is made from 3/16 plate steel. The pieces are just big enough that they're a royal pain to cut precisely. I roughed them out in the bandsaw then, squared them up in the mill. In the picture here, there's just a couple tack welds holding the box together.

Here's the front:



The motor will sit on another plate directly above where it is now and that second plate will be affixed with some adjustable stand-offs. That way, the belt can be tensioned by moving the plate. Some sheaves will be needed but first, I'll need to find a small flat drive belt.

Here's the back:



Anyhow, this will need to grind along for a while longer. This is what happens when something is being made from shop drops. One part of me loves to improvise... the other part of me hates how much longer it takes to get things done properly when you're "winging it on the fly".

Ray

 

[Ray C]

We're getting there.... We're down to the last quarter mile or so.

It' welded-up adequately. I didn't use filler rod, just fusion welds everywhere. The top part bolts to the heavy base plate with some 10Mx1.5x25 socket head bolts. It's in the final position but is just balanced up there. The bolt hold that allows it to attach to the column is not drilled yet.

I've got to focus on determining the proper diameter belt and start tracking one down. ...And all those edges and corners need to be rounded down.

Lot's of steps to go. I should probably make a list...





That's it for today...

I'm going to chill for a while and listen to the wind. It's pretty bad around here today. 75MPH gusts. My neighbor lost a tree a few hours ago.



Ray

 

[Ray C]

Here's the platform bolted to the column. Once that bolt is tight, the assembly is rock solid.



Turns-out, I had a 24" OD, 3 groove serpentine belt in the shop. I won't need to order one. So... it was time to make some sheaves.

This bar is 4" diameter and pretty darn heavy. It's giving the 8" chuck a run for it's money.



To clean off the scale, you don't wear your best Sunday carbide. I keep a few ratty inserts around for just such occasions. This made a mess. It also gave this 1236 lathe a real workout. The motor could handle it just fine but, a large diameter bar like this is pushing the envelope of carriage and compound travel. In all likelihood, I'm going to spring for a larger lathe sometime soon.


Cruising right along... Here's are two nearly complete sheaves. The grooves match the spacing on the belt.


Normally, I would have no problem parting but this piece, even supported with the tailstock, is sticking out too far and is too heavy. Over to the bandsaw we go.


Anyone care to guess how long it took to cut in the bandsaw? Or, if you really want to take guesses, try to guess how many thousandths the width varied after the cut.

OK, more later today...

Ray

 

[Ray C]

Two more pieces to the puzzle. One of them needs a keyway which will be taken care of tomorrow. I'll also make a couple temporary shafts and check them for even balance. The diameter should be big enough to not beat the daylights out of the belt. A sharp turn radius and 3600 RPM will wear out belts quickly.



Ray