Bandsaw Failure

[Vixen]

Not a good day today.

The hinge casting on my Axminster 3-Speed 150mm Metal Cutting Bandsaw has snapped clean across. Not realy sure what I did wrong but it was probably due to that locking pin next to the spring.





I have has this saw for over 20 years. A direct replacement now costs over £400 which is rather more than I paid for it all those years ago.

Has anyone had a similar failure and how did they fix it?

I guess it could be welded or brazed but where can I find someone capable of the job?

Perhaps it could be repaired with some steel straps and numerous bolts, doable but messy.

If I were to buy a new bandsaw, what would you guys recommend, a similar one from China or is there something better that does not cost the earth.

Mike

[wirralcnc]

mike what material is it?

[Vixen]

Cast iron

[AOG]

It could be brazed with a bronze filler rod. Do you have a propane or oxy-propane torch? If so, you could do it yourself.

Tony

[wirralcnc]

it could be replaced with a new machined arm or repaired using castolin eutectic superjet equipment. do you use it daily?

[Vixen]

I have taken the damaged bandsaw apart to try and find a way to do a temporary fix. I use the saw most days and am going to be stuck untill it's fixed or replaced.

As you can see, the cast iron casting has suffered a normal crystalline fracture. There is a suggestion of an earlier partial fracture in the upper arm, even a hint of white paint intrusion. Not that that makes the slightest difference to the problem.



Now what do I do? It looks like I can machine off the cast iron boss, cut this slab of 1/4" steel plate to size and bolt it too the back of the casting. Should not be too difficult.





(Then a quick coat of paint and list it on e-bay. Used, cash only, buyer collects, no returns)

Tony, I do have a big air propane torch and hearth. Perhaps I could braze it, in addition to the steel plate repair. What bronze filler rod would I need to obtain? That may be easier than trying to find someone with the castolin eutectic superjet equipment.

Mike

[cnr6400]

Two ways occur to me, in addition to welding or bronze welding the broken C I bracket:

1. Make an equivalent bracket assembly from bits of mild steel plate and bronze weld it or electric weld it yourself (or have a friend with the welding kit do it)

2. Glue the broken bits together and take it to an iron foundry and ask for a replacement casting using the glued broken one as pattern. It does not look as if high precision is needed except maybe the hole and slot placements.

Good luck in any case. If you were a few thousand miles closer you'd be welcome to come by and do the bits and the welding here. That's how I would tackle it (and have, many times on similar bits) if it were mine. Cheap materials and very strong repair and no waiting for the foundry to get on with it.

[Jo]

Cast iron

Take it to see Eric, Chocolate biccies/cakes will aid his welding 

I have one Cast Iron rod but his welder  is more reliable.

Jo

[wirralcnc]

mike i can stick it all back together for you using castolin kit if yoy pop in post. or plate it with steel and fit a block inside casting. screwing it together from the outside.

[nj111]

I've had excellent results on grey cast iron repairs using TIG and Aluminium Bronze rod (much stronger filler than silicon bronze). Nick  (Super6 C13 being the rod I use)

[kvom]

Drill matching holes into each of the fractured surfaces.  Use steel rod to align them and fasten everything with JB Weld.  When cured you could reinforce it further.

[Vixen]

Thank you all for all  of your helpful suggestions.

That's the great thing about MEM, you all willingly offer assistance, from all over the world.             Great team

Well I wanted to get back in operation as soon as I could, so I went ahead and bolted some 1/4" plate as a steel splint on the back of the fractured casting. It was a quick and dirty repair but it looks to be strong and robust. It's a functional field repair on a piece of workshop machinary, not a work of art.

Some tidying up still required, like cutting the bolts to length etc, but that can wait until tomorrow.





It's a long time since I had the pleasure of machining and drilling cast iron, I had forgotten just how dirty Iron is to work. Then I blow my nose into a clean white handkerchief, now I will have to explain that to Sonia.

Thanks

Mike

[cnr6400]

Looks like a great functional repair! Well done. 

(you did make some sketches and cardboard templates while the bracket was off the machine, just in case Godzilla visits again and loosens your bolts or breathes on your C I a second time,  right?  )

Cracks in C I are often like roaches - there's never just one......

Drop of red Loctite on each thread would not go amiss before final bolt shortening either, just food for thought, if you didn't already...

Forgot to mention - Kleenex when working Kast Iron - that's how I remember....

[b.lindsey]

Nice fix Mike. Should be good for another 20 years.

Bill

[Steamer5]

Hi Mike,
 Nice fix!

Just a thought did you contact Axmister to see if they had any spares? Or maybe Grizzly or one of the other US based tool suppliers?

Cheers Kerrin

[Vixen]

Nice fix Mike. Should be good for another 20 years.

Bill

Ha ha, the band saw may be good for another 20 years, but I don't think I will be.

Mike

[Lew Hartswick]

Quote
< Then I blow my nose into a clean white handkerchief, now I will have to explain that to Sonia.>
 Always use tissue for that op in the shop. :-)
   ...lew...

[Elam Works]

Well problem already solved.

Had the same issue and welded it with silicon bronze. Been so long ago I do not even remember what caused it to break; slamming it up, slamming it down, or looking at it cross-eyed. Bought in the mid-nineteen eighties when these imports started flooding the market here in the States. It broke within the first five years. Whatever the cause, it has held since.

You might notice the drive wheel is not a cast spoke type. Found that tended to slip too much and made a steel drive wheel, double flanged, so it would hold a rubber drive tire (or tyre). In hindsight might have been able to have used the original drive wheel as the rubber tire does not seem prone to move about. The tire is just a sliver of inner tube. That needs replacing about every twenty years.

-Doug

[Vixen]

Hello Doug

It's good to know I am not the only one to have that casting fail. Mine had an extra locking pin to hold it open or closed. It always engaged when you didn't want it too. I have removed it as part of my repairs

Mike