Thread: HM-45 Column Bellow Repair

I am in the process of re-commissioning my Mill after the move, so I can use it, and found the Bellows that protect the Column dovetail was hanging at a 'less than desirable' attitude....
I thought I would be up for a new one,but closer inspection revealed an error during manufacture. ( surprise, surprise...lol)

There appears to be 2off M3 bolts that are supposed to secure the bottom of the bellows to the column. The person attaching them, missed the bellows completely on one side and side that side has pulled out.

I removed the bellows and found remenants of contact cement on the inside of the bellows. Trouble is it would only have glued to the clear plastic inner bellows and not the bellows inself! Not good.

I decided to make a another frame out of FRP so I can sandwich the bellows to secure them in place. I will use about 6 m3 bolts to hold it this time. It shouldn't come out again.

Not done yet, but have a good plan.

Steve

https://photos.app.goo.gl/Ckm4FwisgN9aUtKR9

https://photos.app.goo.gl/zqbCvaYyQEEs5ieS6

https://photos.app.goo.gl/CJNznpkZJ48Py31L8

I binned mine when it did that. I have some insertion rubber resting on the back of the base as an interim, but the column is exposed. When I have a moment I’m going to fold a couple of pieces of ally that allows the piece on the head to slide in behind the fixed piece on the base. I’ll probably look at doing something with the insertion rubber at that point and actually attach it to things.

Hi Steve, Guys,

My column bellows failed in a similar way. So I made up three thin (1 mm thick) aluminium plates and linked them with small bolts and slotted the plates so that they would slide inside each other to replace the bellows.

They do sometimes stick together but a quick tap causes them to drop into position. They are also wider than the column so any swarf tends to either bounce off them or miss them entirely. I also replaced the rubber protector over the "Y" sideways as well.

Hi Greg, the pictures you wanted !

27-07-2021-003.jpg 27-07-2021-005.jpg

27-07-2021-004.jpg 27-07-2021-006.jpg
As you can see just three pieces of alloy plate hung from the lip at the top, also showing the rubber shield over the "Y" slide

A good solution John.

I did some more today and I realised the bellows had been fitted upside down! ( The3 inner guides are biased towards one end. )
I also inspected the top mount and that is dodgy as well, so I'm fixing that as well now.....

Worked out a design for a plate to secure both end sof the bellows and cut them out of some 1.6m ALi plate.
Should work a treat. These still time to mess it up though.

https://photos.app.goo.gl/yrY2MWUxPJtmCwHb9

https://photos.app.goo.gl/gTnjYLZt1SvKS3yu9

I've Gorilla Glued the bellows to the plate, just to hold it in plate while I fit it. Can do th eother end tomorrow.

Steve

Progress made today. I thought I'd finish but there is more work in it than its worth....lol

Both ends of the bellows are sandwiched between 2 Aluminum plates held togehter with M3
set screws.

Now ready to mount on the machine.

https://photos.app.goo.gl/sMxUx7nLE9TSYx3R7

Steve

Sometimes you just do things because you can

Coming along quite nicely

I got it all done and fitted today ( yay!)

I decided to fab another guide and glue it inside to try and keep it in order. Not sure it will work.....
Will lower the Head tomorrow and see how it behaves.

If it doesn't, I will have to add something lto make it!....lol

Steve

https://photos.app.goo.gl/wv5fUY3WxebJTR5cA

https://photos.app.goo.gl/13caoHXsYQYd8FhN9




PS I think you are ahead John....lol

Completely unrelated….

Any chance you could put up a couple of pictures of the motor drive on the column? I’m looking at motors to do mine at the moment, I’d like to see how you’ve done yours.

Originally Posted by racingtadpole

Completely unrelated….

Any chance you could put up a couple of pictures of the motor drive on the column? I’m looking at motors to do mine at the moment, I’d like to see how you’ve done yours.

No probs...see new thread.

I ran the head up and down a couple of times.
Bellows *seem* to be behaving. lol