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View Full Version : Welding Rockwell 28-463 Band Saw Blade Butt Welder - Safe?



Erica Bailey
06-24-2013, 1:57 PM
I found an old Rockwell 115V band saw blade welder in the shop and turned it on and it didn't work. I opened it up, cleaned the connections and reconnected a loose wire. I also cleaned the clamp jaws. Put it back together and it worked. However, I have serious doubts about how safe this thing is since, like a lot of old tools, it doesn't seem very well insulated, AND I suspect it could pack more of a punch electrically than an old hand drill. Anyone, with any experience with these old welders, care to comment on the safety of this machine? What safety measures should I take when using it? Would I be better off purchasing a newer machine that would, presumably, be safer?

George Carlson
06-25-2013, 1:01 AM
You might want to make sure the windings in the transformer or grinder are not shorted to the chassis. You can verify this with a simple ohmmeter. If you know a commercial electrician, he may have a Megger. A Megger can to the isolation test at 600V to make sure there is no leakage. In any case, just make sure the chassis has a good ground, so if the windings do short out, you will pop a breaker and not get zapped. I've used electrical equipment much older than your welder, in fact my Monarch 10EE was built in 1961. I use it almost every day.

Mike Heidrick
06-25-2013, 1:37 AM
I just send my blades in and have them welded. I use Lenox blades and Sanders Tools in Peoria IL does a great job on the woodmaster CTs and trimasters and even has done work on a Resaw king for me. Dave Erhb is who you need to work with there.

Erica Bailey
06-25-2013, 10:57 AM
George, thanks for your suggestion. Consulting an electrician seems like the thing to do for my peace of mind. Once I'm confident it's safe to use, it'll will save us a lot of money! Do you have any idea what year this model was made?

Mike, I do send out other blades in the shop for sharpening, but since we have the machine and it is now working, we might as well save some money by repairing our band saw blades in house. I'll look into the place in peoria and see how they compare to the place our purchasing department has us using now.

George Carlson
06-25-2013, 5:10 PM
One of the advantages of having a welder is that you can thread the cut blade through a hole in the workpiece, weld the blade, and make an inside cut. Almost every contour cutting metal band saw I've seen has a built in welder for this purpose.

You can find a manual for your welder at http://vintagemachinery.org/pubs/detail.aspx?id=4614

Erica Bailey
06-27-2013, 9:34 AM
Most inside cuts that we need to make can be done on the scroll saw, but I'll keep your suggestion in mind. Seems like it could be a bit of pain putting the blade on the machine with the work piece attached! I already pulled the manual from vintage machinery. Never noticed the date in the upper right corner of the first page. '62

Dan Hintz
06-27-2013, 11:54 AM
Making sure the metal cases on old equipment are grounded goes a long way to ensuring their safe use... if anything fails internally, it will pop the breaker (at least a working one... no Federal Pacific stuff))

Gus Dundon
07-05-2013, 5:29 PM
I don't a lot about this stuff. But don't forget to put your safety glasses on. :D

Dave Verstraete
07-07-2013, 9:19 AM
Erica
your post brought back a lot of memories from the 70's. As an apprentice tool and die maker, we had to saw a lot of inside openings through die steels and die sets. Welding the blade was always a little tricky and each saw's blade welder was a little different.
Here are a few tips for using that blade welder. After cutting the blade to the proper length, use the side of the grinding wheel to square up both ends of the blade so they meet up evenly in the welder jaws. Leave the burr that is created during this process on the blade. It will prevent one blade from sliding over the other. Make sure that the blade was not bent a little during the cutting process. This causes one blade to slide overtop of the other during the welding process. Usually we had to put a slight (1/32) gap between the blades to get the right pressure during the weld. Each welder would vary on the amount of gap we used. After a successful weld, grind the burr off with the top and bottom of the grinder wheel making sure not to make the blade too thin. There is usually a gage to slide the blade through during this process. This process leaves a shiny, ground area on the blade. Now put the blade back in the welding jaws and push the annealing button a few times until the shiny area turns the same color as the rest of the blade when it cools.

Hope this helps

george wilson
08-23-2013, 7:03 PM
I always have a blade welder. Other people's wells break too easily to suit me. Sometimes they aren't straight either. I take extra steps to anneal the weld and never grind the weld thinner than the blade. I don't grind at all. I file the weld flush after annealing. When the weld is filed bright,I put it back in the welder,and lightly tap the anneal button till the weld comes up to a spring blue color,just to make sure it is thoroughly annealed.

No problem putting a blade with work around it back in the saw. Just rest the work on the bandsaw table and install the blade in the usual way. Scroll saws are limited in the thickness they can handle. I have sawn 4" thick metal with an inside cut on my metal working bandsaw. Actuallly,welding the blade weigh work around it is more difficult. You need a stool or something handy to rest the work on and not be pulling at the blade.

John Oliver35
08-28-2013, 12:02 AM
George,

I am always amazed at your knowledge on all types of topics, and enjoy reading your Williamsburg stories. Any chance there is a book inside you that needs to get out?