Turning weld metal?

34_40 said:
Barn Lime??? I've never heard of this. Is it just regular Lime or something special?
Click to expand...

It is also known as ag lime and is used in dairy barns to help reduce the slipperyness of concrete floors and to reduce the potential for bacteria growth. It is also used to raise the pH level in acidic soils. It is simply limestone that has been ground to a coarse powder. It should not be confused with quicklime or slaked lime which are very caustic and poisonous. If the bag says calcium carbonate you've got the right stuff, but stay away from calcium hydroxide or hydrated lime, which are the same thing and also the same as quicklime and slaked lime.
 
I agree that not having a key or some other locking device is not optimal but as long as the retaining bolt is torqued properly there is more than enough clamping force to hold the pulley from spinning on the shaft. On this particular machine the bolt was not torqued properly. I'll have to pick up some barn lime and try this trick out. The process used was was GMAW.
 
Barn lime is also great if you happen to have a dog that kills part of your lawn by urinating in the same place all the time. Spread a healthy sprinkling of barn lime over the affected area and water it in once or twice a year.

As previously mentioned ashes will work also. Fine sand will also work but not as well as barn lime.
 
Are you working on known base metal? There are several options. If possible, pre-heat the entire area around the weld at least several inches away from the junction. The pre-heat temperature varies according to base metal but for mild to low/medium carbon steel, it's about 500F. The total area you pre-heat depends on the shape/size of the part. In some cases, the entire part must be pre-heated. After you perform the weld, make sure the surrounding area is at least at your pre-heat temperature. Re-heat if necessary. Wrap the part in a glass thermal blanket and toss it in a suitable container so it cools down naturally and very slowly. If you have a HT oven, ramp the part down below martensetic temp (typically 350 F) over a 5-6 hour period. This will make a huge difference and the weld will be easy to cut.

Next option is to normalize the entire part after welding and heat-treat as necessary. Of course this may not be possible on a finished part that is being modified with a weldment.

Ray C.
 
How stout is your machine?

One trick we have used end mills as a boring bar when we needed to do a shallow or small hole.

A chipped end mill may not be good for milling but great for boring.

You can either come in as a boring bar or go sideways and cut full depth shaving it so to speak to smooth out the high spots.
 
Change the weld wire. Use FCAW and the appropriate electrode or for that particular application Bronze welding would work fine.
 
I just weld and then machine. The only hardness problem I've ever encountered was with a torch cut edge and carbide took care of it.
 
One of my jobs during my apprenticeship was turning journal ends on rollers for a steel mill in Pennsylvania. They were welded with rod on an old worn out lathe head layered to build up the wear . I had a big lathe slow turning ill say it was between 500-750 rpms. Now the diameter was about ten inches by sixteen inches on each end , I used a carbide round tool , insert type. For cutting the weld till it wasn't interrupted then I used a HSS tool bit with a slight radius and good rake angle on top , enough bottom and side clearance not to rub . The breakthrough cutting is the hardest use a little more course feed then you normally use its course material and needs course action to cut it . Yes we used up some inserts but it worked well. Even in castings on the planer and boring mill ,, from the dark ages even in the 70s ,,,.
 
You must log in or register to reply here.
Back
Top