Aluminum weld

[Kez]

Has anyone tried using the low temperature aluminum welding rod such as this for repair?

https://www.harborfreight.com/8-piece-low-temperature-aluminum-welding-rods-44810.html
I have a 7.5 lower unit that broke where the hinge pin is held. If this stuff is as strong as they claimed, I am thinking I can build up material where it is broken and then machine it to match the original part. Also, I can make custom tuned pipe headers with special angles and mufflers etc.

Thanks,
k

 

[Tom Foley]

It's really a brazing process , not welding . It could be useful for certain things . I think your K &B lower unit would be better welded . Post a photo .

 

[MitchFarabaugh]

It works OK for what it is. I have not gotten it to work very well with cast aluminum. It's obviously not even close to the strength of a weld.

It *may* work for a pipe, but I think the vibration would probably break the joints in fairly short order. It's also fairly difficult to use on thin aluminum, as you have to get the metal very near its melting point before the rod will flow properly.

All in all, it can be handy to have a few sticks in the tool box, but you're better off picking up an inexpensive AC/DC inverter welder if you plan on doing any real metal fab/repair.

 

[RobertDoak]

I would say give it a shot...you really have nothing to loose....its already broke....and MECOA sells a replacement for $60ish ...
so it would be a learning experience...

 

[Timbo Whalen]

Has anyone tried using the low temperature aluminum welding rod such as this for repair?

https://www.harborfreight.com/8-piece-low-temperature-aluminum-welding-rods-44810.html
I have a 7.5 lower unit that broke where the hinge pin is held. If this stuff is as strong as they claimed, I am thinking I can build up material where it is broken and then machine it to match the original part. Also, I can make custom tuned pipe headers with special angles and mufflers etc.

Thanks,
k

Make sure that aluminum casting is VERY CLEAN..... also, it's probably beneficial to heat soak the part you want to repair

in an oven for a while, and CLEAN AGAIN. Preheat part once again before attempting to braze.

Personally, I'd attempt with the Hobart self fluxing rods from Tractor Supply-

https://www.tractorsupply.com/tsc/product/hobart-aluminium-rod-pack-of-8
Or better yet, check the JK Harris series of aluminum brazing rods. Don't hesitate to call them for tech advice.... I've never

had a bad experience with their products, and their StaClean liquid flux (soldering) is the industry standard-

https://www.harrisproductsgroup.com/en/Products/Alloys/Brazing/Aluminum
https://www.harrisproductsgroup.com/en/Expert-Advice.aspx
Their Technical Documents are here-

https://www.harrisproductsgroup.com/en/Technical-Documents.aspx
JK Harris Customer Service- (800) 733-4043 (they're in Ohio)

I use the Dremel torch for all my rc boat needs.... well worth the money spent-

https://us.dremel.com/en_US/product...200-01-versaflame-multi-function-butane-torch
Mine was purchased at Menards, and they have an 11% discount going on until 9/04/2021-

https://www.menards.com/main/tools/...34-c-8533.htm?tid=-6145237909476712677&ipos=1
Hope this helps you.

Tim

 

[Kez]

Thank you all for your replies. Do you think I can build up material with the aluminum brazing rod so that I can machine and shape it?

Tim, thanks for the information. The self fluxing rods look to be similar. The only difference is, and according to the Harbor Freight data sheet, the brazing rod does not require flux. I have always wondered how they can braze without flux.

I have seen an Alumiweld TV commercial. You may still find it on YouTube. They were showing how they build up material on a broken electric motor mounting lug. If that really worked, it should be strong enough to repair the lower. If the repair failed, however, I will not see my outboard again

 

[K F Wheeler]

Hate to be a wet diaper... And you have to know this is coming... If it broke once it's more likely to happen again regardless of why it broke before.
Sorry. I wouldn't even try it!
Ken

 

[Wasted wages]

Yup, not worth losing a motor over ... either that or attach a serious 1/8" cable between the motor and the hull...

If the lower was one complete piece, I might try filling it all in and machining a new hole in it... but it also splits in half at that point, so you actually end up with 4 welded points that are all critical and under a lot of pressure...it's almost a given that it will fail at some point.

 

[MitchFarabaugh]

Tim, that little baby torch will not get anywhere near hot enough for that rod on a part as large as a lower unit.

 

[Timbo Whalen]

Tim, that little baby torch will not get anywhere near hot enough for that rod on a part as large as a lower unit.

Sorry, we disagree..... I've had success doing the process with the Dremel torch on a handful of occasions.

The Dremel torch heats to 1875°F minimum, 3977°F max.

https://us.dremel.com/en_US/product...200-01-versaflame-multi-function-butane-torch
Hobart low-temperature, self-fluxing rod flows at 700°F.

https://www.hobartwelders.com/consu.../aluminum-rod-1-8-in-x-18-1-8-in-qty-7-770206
Also note that we said the part should be preheated (heat soaked, with a propane torch nearby).

We've brazed castings that were actually larger in area and density than those cast aluminum outboard lower units.

Apparently you've no experience with aluminum brazing and the Dremel Versaflame torch.

Tim

 

[K F Wheeler]

My only experience was with a broken tower housing with a Quickie lower unit. And 15 hp power head. Tower housing (unit and clamps between the lower unit and power head on an outboard motor) looked stock from the outside. But after it broke checked inside of the housing. It had been wielded and strengthened with plates of 1/4" aluminum. Still broke. Right about the part needing to be heat soaked. Tim go back to your slot cars! LOL!! Seen Boyt J. since he got married? Been a couple at least since I have. Probably 25 years since I laid eyes on YOU!
Ken W.

 

[MitchFarabaugh]

Sorry, we disagree..... I've had success doing the process with the Dremel torch on a handful of occasions.

Also note that we said the part should be preheated (heat soaked, with a propane torch nearby).

Apparently you've no experience with aluminum brazing and the Dremel Versaflame torch.

Tim

Exactly. You need a SEPARATE torch to get the aluminum up to temp, THEN you can use the little guy to help HOLD the temp and work the solder (although it's usually easier to start and end with the same propane or MAPP gas torch).

The little Dremel torch by itself is insufficient for anything but very small parts with a very small volume.

Just because the Dremel torch will get to 4000* doesn't mean anything without looking at BTU output. A regular Bic under the right conditions (at least according to google) can get up to 3500*. But I don't think you'd argue that you'll be solder repairing an OB lower unit with a Bic would you?

 

[johnsteltzer]

Hell just send it to me and I will tig weld it back together for free

 

[RobertDoak]

So its been 10 days....whats the outcome...its either fixed or trash...

 

[Kez]

Hell just send it to me and I will tig weld it back together for free

Hi John,
Thank you very much for offering to tig weld it back. I will talk to a local machine shop first. But I may take up on your offer. If I do I will PM you offline.
Thanks,
k

 

[johnsteltzer]

Anytime my friend I will weld it back on it will look like new thanks

 

[Wasted wages]

May be relevant....

 

[dwilfong]

Why?

MECOA SHOP ON LINE

 

[johnsteltzer]

Don’t really understand