Paging Britt .... WELDING

@Britt
Welding super-dilemma. Found a broken engine case on the used dirtbike I just bought, to ride & race hare-scrambles/enduros.

The engine case is unobtanium. If I blow it, I'm done. I am very scared.

The damaged internal area is Very thin, w/ Blind access critical machining and also a Blind oil port w/in millimeters of the hole that needs to be welded closed. Very sketchy. (For me anyways, lol).
I was going to Tig it w/ silicon bronze, but someone told me you can't tig/bronze to aluminum.

I made a copper backing plate/rod, to try and keep the internal dimensions and blind oil-galley hole/port from melting/plugging. Then had my friend try, he said he could do it, no prob. My friend tried to tig it w/ 6061 filler using a synchrowave 300, and couldn't get it to "Puddle or Flow".... He aborted the repair very quickly, before he blew an irreparable hole through it.
He said the material is too porous, can't be welded, can't lay a bead, he told me to JB it :/

I have a tig (Miller 180), and out of desperation would try it, carefully try it, w/ some guidance.
What rod/filler should I use? What diameter filler? Amps? Preheat? Propane or Map? How long/hot/temp?
Should I coat the copper plug, w/ any type of heat-repellant(?) to keep the temperature down, to protect the inner machining and blind-oil galley?
Any advice is greatly appreciated.
btw: It is off a Yamaha engine.
Thank you!!!!









BTW,
I posted the case on a dirtbike forum couple weeks ago, when I found the hole/damage.
Two people posted pics of their results, using their local tig welders. So it appears it can be welded, so I dont know why my friend couldn't weld it. Anyways, Thank you again

Pics of one guy's repair (on dirtbike forum), for example of what I am trying to achieve.
1)







Another guy showing example pics that the case(s) can indeed be welded.





Thank you!!!!!

 

Curious - what bike?

 

YZ250

 

Somewhere on a lonely trail in the woods there is a rock standing Proud!! GLW the Fix...

 

Clean. Clean. Clean. Then try 4047 filler rod. 4043 if you can’t find the 4047.

 

Brake cleaner? Acetone? Plug/protect inner surfaces & Alum-Oxide blast outer surface? Wire (steel) wheel?

 

Quote from the dirtbike forum, couple weeks ago ...
""Would use 4047, 4043 or 5356 filler metal.""

 

If you’re within 3 hours of Britt, beg him to do it for you. Take the bike there, thank him for doing it and leave. Don’t hang around asking questions and sure as fuck don’t offer to help. When it’s done, pay him whatever he charges you, DO NOT haggle on the price, do not ask him questions, thank him and get out of there before you piss him off and he kills you.

Follow the above and it’ll be fixed right and you run the chance of he might do some work for you again. Mess it up, don’t come here complaining that you now have a ball peen hammer in your forehead and his boot is wedged so far up your ass that scientists want to study the combination for future generations.

 

I know, Right?!?!? That would be who I would trust more than anyone(!!!!!)

I'm way far away from Britt

 

Fedex UPS and USPS all can get it to him.

 

In a Heartbeat, I would .... I would send it to Britt in a second(!!!!)

 

Clean it good CLEAN it AGAIN, warm it up, weld it...I like 4943 but 4043, 1/16 will be fine, 3/32 would work in a pinch, use Pure tungsten 3/32,...warm up that copper part too, you;re just filling in a hole.it ain't rocketsurgery..after you weld it...let it all cool down, dead cold..then remove the copper..if it is stuck..warm the cases and pull the copper out..
Preheat it so it is all warm to the touch..make sure to ground the part so it won't arc off and eff up the edges.
(They don't make Mapp Gas anymore haven't for long time, the last plant that made it closed in like 2007/08)
That is an investment cast case...not some porous sand casting..they usually weld very well when clean. That actual weld should take no longer than 2 min..start to finish.

 

Don’t fill it. It looks big enough and small enough to find a spot on the case you can cut from. Make the cut a little square or round piece and bevel it to sit. Use a dremel or die grinder to bore out the damage with a seat bevel so the cap sits nicely. Then braze it with bronze. Make sure you leave a little bit of space in the perimeter opening (like a needle width) so the bronze can flow.

and like the guy above me said. CLEAN. CLEAN AGAIN. THEN CLEAN AGAIN. Heat the casing up enough to burn off any residues in the metal but not melt it before you actually start welding

 

May as well just use fucking JB Weld..

 

Acetone and then use a clean (brand new) stainless steel wire brush. Then wipe again with acetone using a lint-free rag. It probably wouldn't hurt to do this before and after pre-heating.

Are you using an inverter or a transformer based welding machine?

 

A little bit of

I’d rather throw it away if that were the choice. I love working with metal.

 

OP where are you located?

I can weld some real thin stuff.. I have different types of tungsten, filler rod, etc. As well as a Miller Dynasty 350 with some settings I've dialed in over the last 18ish years.

 

A new bike will none of these problems.