Thread: bearing damage on jointer cutter head

That reminds me Simon: I have been using electroless nickel plating in the past. You could mask of everything you don;t want plated and just immerse the shaft end in the solution and let it plate until the worn section is back to size (plus a bit ) and then turn it back to size. Nickel is harder than copper, but the principle is the same. But is is an easy DIY option. Jane's have the required solution.

19.05mm is .750"
How about using a piece of 3/4 tube as the sleeve and turn the worn piece of the shaft down to suit the inside diameter.
Split the tube to get it over the long end of the shaft then press the bearing on or just make it a nice slip fit and use Loctite.
If you could get a bit of stainless tube it would likely have enough spring to return to its original size after being expanded.

To hold the other end, what about something like a small spider with a center hole in it.
Take a piece of round stock around 30mm diameter, drill/bore a 20mm hole most of the way through. Face and center drill the non-bored end.
Drill and tap the bored out section to take some bolts that will clamp onto the shaft. I'd think 6 bolts, 120deg apart, in 2 positions along the length.
Chuck one end of the cutter head, slide the spider over the other and insert the tailstock center. Adjust the bolts until the bearing area runs true.

Steve

Wow thanks everyone. I really underestimated the options available. All have their merrits. I have since had a bit of a play with the cutter head. Today I made two brass slip rings that are a push fit over the cutter barrel, one for each end. I then mounted one of the bearing mounts in the 4 jaw and placed a DI on the slip ring closest to the chuck. I dialed it in to within about 0.05mm TIR. The other end I supported with the fixed steady on the shoulder next to the other bearing mount. Problem was I had limited success getting the other end of the barrel dialed in to my satisfaction, in truth it was a bit over the place.

I'm thinking Joe may be correct in thinking that the reason the shaft turned in the bearing was because it had a mishap that caused the shaft to bend slightly, creating enough of a wobble to make the shaft preferentially turn on the bearing.

I have for the first time today considered Michaels' suggestion of simply making another cutter head. To make it I would need about 300mm of 3" diameter 1045 Duraflex or similar. Not sure what that would cost, probably under the $100 mark. Biggest issue is I would need to use my dividing head which is not quite ready to use, it too has some parts that need to be replaced/repaired...... and so it continues!

Anyway, I had another idea. How about I mount the cutter head on a face plate? The shaft pokeing through and the cutter would sit on it's end. I have since tested this with a square and it seems the two sides of the cutter and very true and would make a good reference plane. There were a couple of dings that produced some raised spots but once they were cleaned off it sat flat and perpendicular.

Anyway, all ideas but no chips yet. I will be away for a couple of days with work so no real oppotunity until Sunday at least.

I will see if I can get out to take some pics to show what I'm on about later tonight...

Simon

You could also just cut the shaft end off and bore a hole and press in a new shaft end?

If you get in a jam I can grab some material from Ian Stansfield Smith and post it up.

Thanks cask. That maybe anothed wirk around too.

Heres some pics of the rings i made up and how they fit. A bit mor ed meat would have been good but its the biggest piece i had.

Last couple are of the proposed setup on the faceplate. This idea has some benifits because it allows me to set the cutter barrel both concentric and perpendicular regardless of the bearing shaft. If the shaft to be machined is in fact bent then it will get machined out and the sleeve will run true again.

Simon

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Late to the party, but could you mount between centres, turn true across the whole length and then sleeve both ends?


Russ

Originally Posted by russ57

Late to the party, but could you mount between centres, turn true across the whole length and then sleeve both ends?


Russ

Hi there,

Short answer is no. In post #1 I made mention of the fact that for some reason that when held between centres it was not concentric. Holding it between centres using the centre drilled holes from when it was made would have been the obvious choice but for one reason or another (some of these possible reasons are mentioned in the following posts from others) the centre holes were out of alignment.

Anyway today I made some chips. I held it on the faceplate as discussed earlier. I was able to dial it in very easily and it was also nicely parallel. I used one of the brass ring to indicate off. The only issue was I could only indicate for about 170 degrees at a time because of the hold down bolts but I was able to tap it into position so as to achieve minimal indicator movement on both sides of the two bolts.

I also took the oppotunity to face the end of the shaft, which was a little worse for wear. I have also thrown in a pic of the end of the shaft which shows the offset nature of the centre hole which caused me grief when attempting to turn between centres.

The shaft has been turned down from 3/4" to 18.00mm along it's length. Next will be to make a sleeve to match, heat and shrink it on and then turn back to 3/4"

I used a saddle stop to turn to a nice shoulder. Im pretty happy with the finish. Its definately a Duraflex type material.

I can also leave the cutter head on the faceplate which makes life easier.

Simon

Nice work Simon. I’ve never looked, but can you get a bearing with the same OD, but a smaller ID? Would save sleeving.

Might be worth truing up the centre while you’re at it.

Thanks jack.

I have opted to keep the same size for couple reasons;

For me its just easier than to source another bearing combination with same properties

And if i did then it would sure mean me having to take off even more metal and i dont want to weaken it any further.

I much prefer to keep things standard where possible.

Simon

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Originally Posted by eskimo

get it hard chromed...and then turn down.

You can't turn Hard Chrome.

Originally Posted by franco

Years ago I got an early twenties Austin 7 crankshaft main bearing journal which had been turning in the seized main roller bearing copper plated and turned it back to size. This worked OK - no problems in the time I owned the car.

Frank.

yep we did it on compressors with shafts spinning at upto 30000rpm

Originally Posted by Techo1

You can't turn Hard Chrome.

okay grind down..same thing..you make it smaller

Thanks Eskimo. I dont have a means of grinding a shaft atm. However (and i digress) there is a nice hercus 3A cylindrical grinder for $1000 OBO on gum tree which is tempting!

Anyway, i turned up a small bush about the same length as the bearing. Bored the centre out to be a press fit on the cutter shaft. I didnt want to press or hammer the bush on in case i damaged the bush or knocked the cutter barrel off centre on the face plate. So i heated cherry red and it then slid on nicely and seated at the shoulder. After it cooled, it was tight as.

I then mounted the face plate back on the lathe and turned the OD of the bush to final dimension of 19.05mm.

A test fit of the old bearing shows its a tight press fit but the bearing does start to slide on the bush. I may need to touch the bush with some emery to fit the new bearing when it arrives.

I will leave the rest of the shaft at 18.00mm and make a bush for the pulley to fit the new dimension. That way the rest of the shaft is about 1mm smaller in OD from where the bearing seats which is a better design anyway.

The last pic the bush is turned to final dimension. Its about 0.525mm wall thickness so difficult to see in the pics.

Im nearly back in business with this.

Simon

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Had a little more time so i bored out the pulley, turned another sleeve, press fitted it into the pulley and the bored the hole to 18.02mm for a neat push fit onto the shaft.

Last thing to do is the internal keyway.

Simon

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