Band Saw Blade Welder Help !

[JoeLee]

I broke a band saw blade yesterday so I decided to drag out the old welder. It's been sitting under the bench for years. I've been meaning to restore it one of these days but just haven't got around to it. Anyway............ I couldn't get it to weld worth a darn. I guess you would call it an incomplete weld. It just fizzeled the ends of the blade a bit but wouldn't weld them togather. The clamp moves as it should and I tried all the different settings but still no luck. Anyone know what I should look for?? I ended up tig welding the blade togather, it worked for about 15 min. and then broke in another spot. I guess it's just stressed out. Haven't changed it in about 4 years and it's done a lot of cutting.

JL............

http://i911.photobucket.com/albums/ac317/JoeLee09/My%20Plug%20Cutter/My%20Pistons/Welding%20Problem/Band%20Saw%20Blade%20Welder/DoAllWelder.jpg

[rebel54]

looks like you are missing the top hold down plates. You may not be getting a good ground with the saw blade. Also remove any rust that would prevent a good ground.

[JoeLee]

Everything is there.

[rebel54]

We have a welder like the one you have where I work, it has plates that slide in the grooves where the screws go through. May be this one is different.

[kjbllc]

there is a certain sequence that you use , look up do all and find the book online for it, they have to be clean also, YOu may know all this already so sorry if you do.

[BobWarfield]

That welder looks like it came off a WWII submarine, LOL.

There is a YouTube video on blade welding. But I'm with the theory it isn't making good contact from the look of the machine.

You're sure it worked when you put it under the bench, I suppose?

If it might not have been working then it could be a lot fo things.

Best,

BW

[JoeLee]

I don't know what it came off of other than a DoAll band saw at one time. But this model was made from 1944 to 1949.

JL...........

[Michael Hall]

JoeLee

Have you seen this:

http://www.garagejournal.com/forum/showthread.php?t=34928

If the rebuilding of the saw doesn't interest you (great job) if scroll through he shows the rebuilding of the blade welder. I believe he has the electrical schematic posted.

DoAll has all the manuals for their blade welders on their web site.

I have the same welder that I also need to go through, time permitting.

Michael

[JoeLee]

I just thought of something............

The blade I'm trying to weld is cobalt. I'm wondering if there is a special blade welder for this kind of band ?? When this welder was made there were no exotic alloy blades. Anyone out there know more than I might on the subject ??

JL..............

[Michael Hall]

JoeLee

I know I've read several times that these old welders will not weld bi-metal blades. Having looked at both the DBW-1 and DBW-15 schematics I found no fundamental difference other than the size of the transformer. I believe the DBW-1 is 4.5kw where as the DBW-15 is 7.5 IIRC. So I called DoAll and they said they see no reason why the DBW-1 would not weld bi-metal blades. However they said one should follow the annealing instructions in the DBW-15 manual. If anyone here can explain a difference in welders I am all ears.

Michael

[DougA]

If you only use one blade every 4 years it isn't worth fooling around with the blade welder. Your blade is definitely fatigued. I recommend you save yourself some trouble and buy a new one. As far as cobalt goes your blade is made from spring steel. Only the very tip of the tooth is M42 so it has nothing to due with your welding. If I understand you correctly it sounds like not enough upset pressure but I have no idea exactly how yours works. Ours is a large production welder so the upset pressure is adjustable. I have several customers that have these welders and most save themselves the trouble of dealing with bad welds and just order the blades from us pre-welded.

[dezy]

Perhaps the saw is too tight on the blade tension. This could break the blade any number of times. I doubt the blade has fatigue. If the saw has numerous years on the blade, I forgot how to tension it?

[DougA]

Perhaps the saw is too tight on the blade tension. This could break the blade any number of times. I doubt the blade has fatigue. If the saw has numerous years on the blade, I forgot how to tension it?

You doubt the blade has Fatigue? Its been going around bending and straightening for 4 years. Even spring steel is going to fatigue unless its almost never used.

[bborr01]

It could be the cobalt blade thing. I purchased a bunch of odd sized starret blades a few years ago for cheap and brought them to work to cut them down and weld them on a kalamazoo startrite saw that had an ideal blade welder on it.

I had welded dozens and dozens of blades on it over the years mostly because most of the guys in our toolroom didn't want to take the time to learn how to properly weld blades.

Some of the starret blades were high speed steel. They were a no go.

The metal crystallized and would not weld worth a toot or anneal.

I had welded many carbon steel blades and later we changed over to bi-metal blade stock and they all welded great.

I would try welding a carbon or bi-metal blade to see if that is the problem.

BTW....I later purchased a saw almost identical to the one at work with the same blade welder. The welder says 460 volt only and they mean it.

That blade welder will not work with 240 from a rotart phase converter.

Good Luck,
Brian

[JoeLee]

Well guys thanks for all the info. The blade I was trying to weld is definatly fatigued, and has served me well, I was just experimenting with it I have other good ones. Was just trying to get this welder to work. A few years back I got several blades for a song, only they are twice the length for my saw. I had always figured on making two blades out of each. For me it's definatly not worth buying bulk band and making them up.

JL.............