Loose stern tube

I am building a steel sailboat. The stern tube is about 4' long and welded in.
What happened is this. When I machined the tube, some 14 years ago, I didn't have the bearing in my hand, however, I followed suggestion of people who sold it to me. Eventually I found the fit is way too tight, by this time the tube was all welded in. Fast forward, I decided to open it up (definitely the wrong decision) with a hand reamer because 1 1/2" honer just didn't do it. Now the tube is 0.008 larger at the outer end and -0.001 at the inner end. The difference is due to a leading edge on the reamer about 1 1/4' long. They recommend .002 interference fit. I have Johnson Duramax "CINDY', 1.627OD for 1 1/8" shaft, phenolic case. Is there a fix for this? I know there are in-line boring machines around the world, my pension wouldn't cover it. I read something about the epoxy, basically to smear a bit on it, slide it on shaft and into the tube. God help me when I'll be replacing it. This is now 4th day without sleep over this.

 

If the bearing is a Novasteen type material, certainly epoxy glue it into place, no worrires mate. They can be easily removed using a hacksaw blade when required. If the bearing is a bronze/rubber type then make sure that you just use a set screw to secure the two metals together, drill and tap them both after installation to stop the cage skating. Do not loose any more sleep over it all, you are being way too concerned over bugger all really.

 

I agree. If you glue it in, just use a sawzall to cut the bearing longitudinally when you need to replace it. Then pound it with a hammer and chisel

 

I had almost the same prob. The only cutlass bearing was imperial or metric I forget,-- but it would not go in without sledge hammering it and damaging it.

SO-- I got some threaded rod with two nuts. I then got a 4 inch grinder and ground away at the concrete floor beneath me to make the disc small enough to fit in my stern tube.

I them simple mounted the disc onto the threaded rod with the 2 nuts and put the tool in a drill.

Within an hour grinding and keep trying the bearing I got it to fit in.

There may have been places that I took of more than necessary but so what.

When your finished make sure you have a grease nipple in the steel stern tube. It protects it from the sea and will seal the stern tube without being tight.

If you want to lay the boat up a few pumps of grease will stop ALL drips.

 

Thanks. I think the glueing way is the easiest to install. I have Industrial Formulators epoxies, top notch. Once they harden, only machining the bearing out would work. I read somewhere, there are epoxies that start melting above 80 Deg. C. This would ease the removal big time, just heat it up witout burning the pain off. Anybody knows the name and can I buy it in Canada or US? I talked to my supplier, he never heard about this.

 

Most of them are in that category.. if not sure make small a test..

 

epoxy

Permatex threadlocker may have an application here. Check with the manufacturer for specs.

 

have someone good at welding build it up on the inside grind it smooth and have another go at it