Cast iron repair - RJH sander

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RC23

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Hi all,

just acquired an horizontal RJH 6inch bandfacer. Pictures below.

Everything works as it should, however one of the cast iron side brackets has broken. Has anyone had any experience of cast iron repair?

I have emailed RJH to see if they have a spare part, but due to the age of the machine I am not holding out much hope!

I have heard of people welding cast iron but think this is not really an option due to the size and fiddliness. Which leaves me with trying epoxy, I have heard JB steel weld is good at cast iron repair. Does anyone have any advice?

Also for those interested, going to give it a new paint job, thinking Anthracite grey or Lime green!
Rupert
 

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Cast iron can be welded, I’ve successfully MIG welded cast iron. The best method is to braze it together. However, it looks a to be a simple plate, made from cast iron only for expediency of manufacturing. I would make a new plate from say 8 or 10mm steel plate. Looks like 4 drilled holes and you will have a far better replacement part than the original.
 
Hi

Yes it can be welded, have done cast iron manifolds and brackets with gas but you need to preheat the item and make sure it cools down very slowly afterwards, we used sand pits and ovens. As mentioned you might be able to make a new one from steel plate but it may have been cast because it has a bearing housing in it, then you would need a new steel bearing housing turned up and then weld that to the new plate.
 
Cast iron can be welded, I’ve successfully MIG welded cast iron. The best method is to braze it together. However, it looks a to be a simple plate, made from cast iron only for expediency of manufacturing. I would make a new plate from say 8 or 10mm steel plate. Looks like 4 drilled holes and you will have a far better replacement part than the original.

Agreed: If it is just flat on the back then make a new one from steel.

Use the original as a template and buy yourself a set of transfer punches to get the holes in the right places (~£14 from ebay):
https://www.ebay.co.uk/itm/Silverli...326433&hash=item5217de4988:g:10QAAOSwiDxff2os
 
Thanks for the advice,

Just took another look, it does have a bearing housing on the other side. Tomorrow will see if I can take it all off and have a proper look and see how it is attached, and measure it up.

think making a new one from steel might be the best way forward. Flat steel is not too expensive on eBay and bearing housings don’t seem to expensive either. I can drill the holes, will just need to find a local welder.

will post some closer photos tomorrow.
 
If you can take the measurements and use a CAD program, then the other option is that it could be milled out of an aluminium block with a not-high-end cnc machine if you know someone with one.

Then there is the Next option that once you have a CAD model, then you can send it to various ‘print bureaus’ to have it printed in steel / titanium / aluminium.
 
Remove from the machine, bevel the edges of the break, align and clamp the 2 parts to a flat support , and bronze weld it. About half an hours work. Unfortunately I live in Kent; otherwise I'd do it for you while you wait.
 
Hi all,

Managed to get it all apart today. Pictures below.

the bearing had failed, it was clogged with detris. I think it was a self aligning type, stuck at an awkward angle. My guess is that was what made the bracket crack, by putting too much stress on it.

RJH got back to me today, they still do replacement parts! Shock! However new bracket £96.15 +VAT!!!!

Replacement bearing is £10 on eBay. However the Old outer ring is completely stuck. Think I may need to get some kind of bearing puller to get that thing out.

So torn, do I just make a new bracket out of steel, and get someone to weld on a 20mm diameter rod to mimic the old bracket, or do I just repair the old bracket. limey Lurkey maybe dropping you a message!
 

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This may or may not work in your situation but has got me out of the poo in the past. Make a flat steel plate using 10mm but don't drill the fixing holes yet. Find a bolt that has a plain shank that will fit nicely into the bearing, if you find one then cut the head off and clean the end. Now drill hole in the plate and using two nuts secure bolt into plate. Put into the bearing a align using mag clamps so you can mark fixing holes, drill them and attach. If you cannot find bolt of right size it is easy job to get it turned down but it needs to be a good fit like the pin on brocken plate.
 
I've had success with stick welding cast with the proper rods. Preheat and a slow cool.
 
I had a cast iron support break on a Startrite sander, a curved support. I put a plea out on one of my forums asking if anyone could weld cast and a fella offered from Scotland, posted it up and he did a great job. It has been going strong for 8 years or so. Find someone and get it done.
 
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