102 Clunking Milling Machine Repair 

Awesome you fixed and did not have to pay repairman. I love saving money on repairs and doing it myself.Another awesome video Watching in Alabama

That variable speed system is a very simple version of a CVT found in some of today's vehicles, a belt and a couple of variable pulleys and you basically have infinite speeds. Great video and explanation of what went wrong and how its easily fixed.

Sounds great now. Nice repair!

Speed Selector makes variable speed pulleys that replace the Reeves, Hi-Lo pulleys and TB Woods that went out of business or got bought. Most of the pulleys are in stock or Speed Selector will custom make if needed. They have an actual engineering department who were very helpful.

Always nice to find that it doesn't have to go to the manufacturer for repairs. That wrench left a bit of a mark on the motor. A Sharp Impact.

In the last two days I rebuilt my Supermax head and my Acra head. Both are late 1980's variable speed machines that were purchased new with Anilam Crusader II CNC retrofits. More recently they have been upgraded to the Acu-rite MILLPWR G2. The Supermax is a better design (in my own humble opinion) when it comes to access to the internal components and removing the motor. The Acra head is much more of a challenge. The first thing you should do is to compress the spring by the screws mentioned in the video. Both of mine take 10-32 screws. To make it easier initially, crank the variable speed until it is at minimum spindle speed. This will compress the spring and allow you to use shorter screws to compress the spring to the maximum thus opening up the pulley. If you have to disassemble the pulley from the motor you will need several screw lengths. When the spring is uncompressed it will take rather long screws to start the compression. Once they are bottomed out you remove one and swap out for shorter screws one side at a time. Repeat the process with progressively shorter screws until the spring is completely compressed. When re-mounting the motor I use tie-wraps to hold the belt open and in an extended position so it will slip more easily onto the pulley. Your mileage may vary.

Our near identical Saber branded mills use M6-1.0 bolts to compress the drive pulley spring. Tip: Get a bunch of lengths. When you go to safely uncompress the spring, you compress 1st to get the snap ring out, then walk out 1 bolt (pay attention to how much threaded length you have left!) and swap it for a longer bolt and draw that longer bolt in. then loosen out the shorter bolt and swap that for a longer one, repeat this alternating/stepping to larger bolts until it is relieved enough that you can easily press it with your hand. Similar for going back in. *do all of that with it on the motor shaft. It will keep things from shifting in a bad way and if something does break give that some direction/constraint. Also, you will probably need to make a special tool with 2 bolts spaced for the holes in the washer, so that you can realign the washer holes with the threaded holes when you need to service this or the belt again in the future.

great repair,enjoyed

Very informative and well presented....!

I'm hoping my Lagun FTV-2S has the same type assembly. As far as clunking sounds, it isn't bad at all, but it is noticeable and it's getting worse. Realizing suddenly there may be eventual keyway damage, I may need to investigate and repair sooner rather than later. Thank you for the awesome info!!

Nice job! I always wondered what those looked-like inside...

That was interesting, as I don't have a Bridgeport-style mill (yet) and was wondering how the variable speed mechanism worked. I didn't realize it was two variable sheaves like a car CVT. What a difference in noise, good repair!

Great repair . From what i have seen it can be a bit of a juggle to get the motor back in . I did get my one fired up , the noise is worse on camera but it has been sitting for years so i am hoping for the best . Cheers .

On my mill (Kent KTM- 5VK) which is also a rebranded Topwell like many, there were two of the access cover bolts that were longer than the third. These two bolts are the spring compression bolts for removing the lower sheave.

The old reach around and fondle in the dark technology, classic all round utility remade, timeless classic still relevant today.

Nice video and good repair...

That went fairly well. I need to replace the bearings in my mill. Not looking forward to it.

these day's, i ALWAYS check youtube for a video before i repair stuff. H&W machine in ft wayne IN has videos on this very repair

Thank you, yes.. I was wondering how I was going to put it back together by myself. I will do it and put to 5/16 bolts in it and do it the easy way thank you. Sorry you had to do it the hard way but it did show people there is an easier way to do things! haha!!

Your ears are going to love you now! What a difference...

Glad you could get parts and no damage to the shaft In the older units of this type the rebuild kit had a mandrel and you set the bushings into epoxy to restore a good fit Now most you have to buy a complete new pulley

Sometimes we can get lucky. Great video, thank you for the great information.

👍 Al.

Would those screws open that pulls up enough to make installation easy?

Holy crap...this is what my Acer 4VK sounds like.... THANK YOU!! What's the part number of those bushings?

To have a fine machine sound like that.. Ouch, that must have been awful to listen to, and worrying about how bad the problem could be. Happy for ya. Did you do a happy dance? hahaha

What kind of bearings in it?

Sir, please, can you share where did you buy the bushings?

Our SuperMax May have similar problem

Those rattling variable speed sheaves are the major reason I never liked variable speed heads. Make of the mill is irrelevant, they all do it.

The holes were not 90° off when you had the keyway lined up correctly. At first I thought you were joking.

My rule number 1, I always blame the wife too. I can usually get a new tool out of the deal. Glad you didn’t have to send it out for repair