# Brake cam and handle for Clausing 8520, 8525, 8530, 8535 mills



## Terrywerm (Oct 13, 2014)

Some time back I promised member 34_40 that I would make him a brake cam for his Clausing 8520 mill, as his is missing. A piece of 5/8" W-1 stock is in the Keller at this very moment, cutting off a piece from which I can make the brake cam. I promised him that when I got around to making the new cam that I would include pictures and a short thread on making the part. 

It is a very simple and straight forward part, but would be a good project for a budding machinist. For the benefit of others, I have included a drawing of the part including all dimensions should anyone ever feel the need to make one of their own.

View attachment CLAUSING 8520 BRAKE CAM.pdf



ON EDIT:  I found a mistake on the drawing. I have the overall length of the brake handle listed as 4" but it should only be 3".  Must have been using one of those upside down rulers again!


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## 34_40 (Oct 13, 2014)

I saved the print "just in case"! )

Thanks so much!


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## wa5cab (Oct 13, 2014)

Terry,

Suggest uploading the PDF to Clausing/Lathes.  It looks like that function is working.  I don't recall whether that folder is moderated or not and can't at the moment check.  If it is, I'll release it as soon as Nelson has time to get those functions back.


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## Terrywerm (Oct 13, 2014)

Thanks Robert, good idea. I posted a document there yesterday about the bearings for the Clausing 8520 mills and had no problem.


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## JPigg55 (Oct 14, 2014)

Terry,
If it's not too much trouble, could you post pictures of the working end of the brake ?
Mine has the brake handle intact, but doesn't seem to do anything. Not sure if it's badly worn or missing something.


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## Terrywerm (Oct 15, 2014)

JPigg55 said:


> Terry,
> If it's not too much trouble, could you post pictures of the working end of the brake ?
> Mine has the brake handle intact, but doesn't seem to do anything. Not sure if it's badly worn or missing something.



Here is the photo and a description of how it works, although it is rather self explanatory. Please pardon the fact that I have not yet cleaned and repainted this machine. Yup, she's a bit of a dirty girl!!:yeahbaby:




The brake plate as it is called in the parts list, is a split ring that sits under the upper spindle pulley. The plate has two tabs attached to it, and they straddle the brake cam. When you pull or push on the brake handle, the brake plate is pushed out against the pulley, stopping the spindle. Keep in mind that the pulley is made of aluminum, and it will soon wear away if the steel brake plate is used when the spindle is rotating. For that reason, I would avoid using the brake to stop the spindle, it usually stops pretty quickly on its own. I use mine only to hold the spindle when I need to do so.

The brake cam itself is retained by a setscrew that engages a groove in the cam. There are two setscrews in there, with one locking the other in place. Obviously, the first screw only engages the groove, and does not get tightened against the cam. Without the second setscrew, the first one would eventually rattle out due to vibration.


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## Terrywerm (Oct 15, 2014)

I also made the new brake cam for 34_40's machine. The cam is made, but I still need to make the handle for it. Needed a chunk of 5/16" rod and didn't have any, so I need to pick some up before I head for work today.

Started with a piece of 5/8" stock, cut to about 1.75"   Put it in the lathe, faced off one end, then flipped  it over and faced it to length. Next step was to cut the taper on the one end.






Next, I cut the .155" wide retainer groove using a parting tool. The tool was .125" wide, so two plunge cuts were required, the first being full width, then moving over .030" and taking the second cut. Please excuse the blurriness of a couple of the photos, I got too close for the camera to focus properly but did not realize it.





The next step was to spot the tapered end with an end mill. This creates a flat spot that can easily be drilled. The first step in this process was to set a v-block in the mill vice and set it to the correct angle. I could have used a sine bar and gauge blocks to set it perfectly, but this is not that critical and using the protractor was much faster.





Once the v-block was set, the part was clamped in place, and the part was centered under the spindle. This is also a demonstration of why we always use some method other than 'by guess and by gosh' to locate the part in relation to the cutter. You will notice that I did not get the flat spot perfectly centered. 





Without changing the setup, a drill chuck replaced the end mill, and the hole was drilled 1/2" deep with a #3 bit, then threaded using a 1/4"-28 tap. The only step after that was to mill the two flats on the end opposite from the taper. The part was mounted in the mill vise using the v-groove jaws, but I could have just as easily used a v-block. I used a temporary handle to properly align the part in the vise so that the flats will be parallel with the handle. Milling the two flats was very straight forward, simply removing .125" of material from each side.







After both flats were milled, the part was removed from the vise and deburred with a file and emery cloth. This completes the cam, leaving only the handle to make.


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## Terrywerm (Oct 21, 2014)

Well, I made the handle and installed it into the cam. The handle is plain old 1018 and the cam is made from W-1 tool steel. I started the wife's oven at 450°F then headed back out to the shop and got out the MAPP torch to heat the part evenly to the point where a magnet would no longer stick to it, then quenched it in water. From there, took it in and put it in the oven for one hour. After it was done with tempering and had cooled, I polished up the handle part, but just oiled up the rest of it. It looks just like the factory brake cam!!





So, it is now in a little plastic bag, waiting to get packaged up and sent out in the mail.  I seem to have run out of packing tape, however. Guess I'll have to pick some up!


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## 34_40 (Oct 22, 2014)

Thanks Again TW!  I also learned a few things from this thread.  Like the use of the angle block and protractor..  a new "trick" for me!

I'll keep my eyes peeled for the mailman now...:ups:


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## Terrywerm (Oct 23, 2014)

Glad to know that you learned something!!  That was the whole reason that I posted the steps that I went through to get it made for you. 

On that note, I've been thinking about starting a 'Beginner's Series' of simple projects that those new to the hobby could follow. Users would learn the basics as they go and would make something useful as a result. The series would start with some simple projects like tap holders, machinist clamps, vee blocks, sine bars, etc, and would increase in difficulty as we went. Drawings would be included for each project. I am hoping to get it off the ground this winter. I just need to come up with a difficulty rating system so that each project ends up with a 'difficulty score'.  Since nothing can guarantee that I would make the easiest thing first and the hardest thing last, I need to have a way to establish a score for comparison. Gotta give that more thought.  

I was out of town for a couple of days, and I finally got it into a Priority Mail box and have it ready to go. It will go out in tomorrow's mail. You should see it early next week.

Time to get out in the garage and get started on the base pin for a Ruger Old Army for a friend.


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## 34_40 (Oct 24, 2014)

The "Beginners Projects"  might be just the ticket for many of us who are trying to learn some new things plus it'll be things we can use like tools.


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## 34_40 (Oct 28, 2014)

The handle arrived yesterday and I'll probably get it installed over the weekend.

Thanks so much TW for your work!  It looks better in person too!


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## Terrywerm (Oct 28, 2014)

You are most welcome, glad you like it!


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## 34_40 (Nov 1, 2014)

I did get the cam assy' installed today.  I found the right thread setscrew in my box but I don't like the contact with the cam.  
So I'll probably turn the end so it's more blunt and fits better into the cam slot and doesn't ruin the edge of the cam. 
I'll also turn up a appropriate handle, maybe in aluminum and polish it out!

Thank You so much Terry!  I think it's wonderful how you've helped me! ( and everyone else here )  You're a real asset to the site!


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## Terrywerm (Nov 1, 2014)

You might want to try putting a small piece of brass or nylon in the hole, under the set screw instead. I have been thinking about changing mine to a piece of plastic, and here is why:  If the setscrew is too loose, the cam will vibrate and rattle at certain speeds. Drives ya nuts!!   If the setscrew is just a hair too tight, it will keep the cam from vibrating but it can keep the cam from returning to the fully 'brake off' position, causing the brake plate to rub on the inside of the pulley, also making noise.  I am thinking that putting a short piece of nylon in the hole first might help to resolve both problems, but am not sure at this point. Will have to try it and see what happens I guess.

If you use just a setscrew, you will need to use a second one behind the first, using it as a locking screw. If you don't the single setscrew will tend to loosen up with vibration.

Thanks for the kind words, but you must remember that my reason for being here is to share what I can as well as learn what I can. It's a two way street ya know!


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## jlchapman (Apr 29, 2017)

Terrywerm -  Just wanted you to know that your pdf was great for creating the brake cam for the 8520.  I'm attaching a picture of my first attempt.  I made the groove to deep.  Just have to remember that .001 really means .002 metal removed.   I got my v-blocks today, just need the new bearings for my 8520 mill.  Also waiting on a bottoming tap for the handle.


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## Terrywerm (Apr 29, 2017)

That looks pretty good, and thanks for the kind words about the drawings. Don't lose any sleep over the groove being too deep, it will not affect the part or its function in any way whatsoever. But, yes on most lathes, the crossfeed dial indicates the distance that the cutting tool has moved and the resulting change in radius, not the reduction in diameter. But, making this mistake on this part has taught you something that you will not soon forget, and you are now a better machinist for it.


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## pashooter (May 22, 2017)

Great thread - thanks for the drawing and the photos Terry! I have a recently acquired 8520 that came with the cam, handle, and brake plate all missing. Looks like a great (and not super-challenging) project. Does anyone have dimensions, drawings, photos, or anything else that might help me reproduce the plate? I understand the basic function, just need some specifics. BTW - I also have a Logan lathe, though mine came with Monkey Ward badging. I have the original paperwork from when my dad bought it new in 1946. He paid $206 for it, and it cost him $6 to have it shipped Railway Express from Chicago to Virginia.


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## Terrywerm (May 22, 2017)

I don't have dimensions for the plate, but will measure mine when I rebuild the head on mine, which will probably not occur until next winter. I will post them then, maybe sooner if things go right.

Sent from my SM-G360T using Tapatalk


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## woodchucker (May 22, 2017)

pashooter said:


> Great thread - thanks for the drawing and the photos Terry! I have a recently acquired 8520 that came with the cam, handle, and brake plate all missing. Looks like a great (and not super-challenging) project. Does anyone have dimensions, drawings, photos, or anything else that might help me reproduce the plate? I understand the basic function, just need some specifics. BTW - I also have a Logan lathe, though mine came with Monkey Ward badging. I have the original paperwork from when my dad bought it new in 1946. He paid $206 for it, and it cost him $6 to have it shipped Railway Express from Chicago to Virginia.



So I just had my brake shoe welded. What I can tell you is that the head is the size of the inner bore, and the diameter is nearly the bore of the pulley.  
I made a plug for the welder, so he could vee the weld. For the size I just took the measurement of the machined area on top of the head.
The brake is cast iron. It's slit, and has a hole 180 degrees from the slit, and a slit to the hole.
See: http://imgur.com/bczO4Uc
And : http://imgur.com/o4iuFsX
or see the whole thread using my link in the signature... there are other pics of it.


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## pashooter (May 23, 2017)

Thanks guys. Actually Jeff, looking at the photos you posted and seeing how the plate fits in place I can probably nuke out the dimensions by measuring my head and pulley. Since it's not uncommon for these things to crack I have to wonder if it wouldn't be better to make a replacement out of something other than cast iron... something with a little more "spring" to it. Worth pondering.

BTW - that restoration project of yours turned out great Jeff. Really a beautiful job. Seeing that I'm really torn now. My machine is currently sitting in the shop in its three main assemblies (cabinet, column with table attached, and head) which is how I moved it when I brought it home. Somewhere along the line someone decided baby blue was a more appropriate color for this mill than the original factory gray. It's perfectly usable as-is, but now I have to wonder whether I want to go ahead and set it up (and tackle a few projects I already have lined up) or tear it the rest of the way apart and do a full restore. Yours sure is purty. Decisions, decisions...


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## woodchucker (May 23, 2017)

If you don't tear it down, at least check the pulleys. My bearings needed replacement.
I replaced with C2's as the original. In retrospect, I think C3's would be a better choice. C2's are necessary on the screws for the table, but not really on the drive. I think that's why the drive bearings seem to go. They are too tight.. c2's have less clearance, c3's more clearance (clearance is in the ball race)


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## pashooter (May 23, 2017)

Are you talking about the bearings on the idler pulley? Did you replace the bearings in the head too?


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## woodchucker (May 23, 2017)

I replaced the idler, and the bearings on the head pulley. I didn't replace the spindle bearings. They seemed good (thankfully).

I also wound up replacing 2 bearings on the table, so only 1 remained usuable. My Serial # 5148, so I think it's an old one. Judging by some of the sites that go over the mods, mine seems like a real old one..


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## pashooter (May 23, 2017)

I'll check them all - thanks. I ran the machine when I went to pick it up and it was smooth and quiet, but of course it wasn't under any sort of load. I assume the bearings are readily available? Is there a list of "modern" part numbers somewhere I can refer to in lieu of cross-referencing the Clausing numbers in the manual?


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## woodchucker (May 23, 2017)

The bearings mostly are 201KDD  FAFNIR    and 1 x 202KDD FAFNIR under one of the pulleys, and 2x  9105KDD FAFNIR for the head pulley.
All were C2 and Fafnir is no longer, it was sucked up into Timken, but new old stock is available. 

Mine also seemed alright until I started digging in. Then it became obvious that they weren't. 2 were completely seized up, and 2 were rough.
The new numbers for 201KDD and 202 are 6201 and 6202 respectively if I remember correctly for newer bearings.
The C2's are hard to locate. The c3's easy. For pulleys go c3


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## pashooter (May 23, 2017)

Thanks Jeff... will definitely check them all out before putting the machine into service. Looks like those bearings are relatively easy to come by and not too expensive. Having a little trouble finding any of them listed on line that give clearance specs... have to keep digging. Anyway - thanks again!


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## pashooter (May 24, 2017)

Well... I inspected my mill last night and the idler pulley bearings seem fine. the pulley turns freely and if I spin it up by hand it will make three or four revolutions before coasting to a stop. There's no discernible play in any direction and no "crunchiness" at any point in its rotation. Not a final verdict, but a good sign at least. The spindle pulley bearings also seem OK - there's a tiny bit of play if I try to rock the pulley side to side, and it's a little stiffer than the idler (of course it's also turning the spindle and its bearings) but again it's very smooth with no roughness evident. So I'm hopeful...


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