Gunsmithing Welding Crack in Mosquito Slide?

[rg1911]

I just received a used SIG Mosquito I got in a Gunbroker auction. While thoroughly cleaning it before taking it to the range, I saw that the back of the slide is cracked.

My first step was to tell the gun shop in Florida about the problem, and emailed a couple pictures. I'm awaiting a response.

The second step was to call SIG and ask about repairs. The answer is $155 (including shipping) and they don't have any more black slides available; just some camo job. They insist that the complete pistol be sent because slides have to be fitted. (Huh?)

While awaiting answers, does anyone weld an aluminum-zinc (I believe) crack? (I suspect not, but have to ask.)

Thank you,
Richard

 

[diverdon]

They are junk, toss it in the garbage.

 

[Tiger_Shilone]

Aluminum zinc alloys aren't weldable. That would be the 7xxx series of Al . The other non weldable Al alloy is the 2xxx series alloyed with copper. They can be braised or soldered. 7000 series Aluminum is the strongest of the group and stronger (but more brittle) than some mild steels.

1xxx, 3xxx, 4xxx, 5xxx and 6xxx series Aluminum alloys are weldable.

Sorry for your misfortune, hopefully there is a means of correction back at the seller. Good luck.

 

[rg1911]

They are junk, toss it in the garbage.

Sorry, I'm not that wealthy.

 

[rg1911]

Aluminum zinc alloys aren't weldable. That would be the 7xxx series of Al . The other non weldable Al alloy is the 2xxx series alloyed with copper. They can be braised or soldered. 7000 series Aluminum is the strongest of the group and stronger (but more brittle) than some mild steels.

1xxx, 3xxx, 4xxx, 5xxx and 6xxx series Aluminum alloys are weldable.

Sorry for your misfortune, hopefully there is a means of correction back at the seller. Good luck.

Thank you for the informative answer. This is what I suspected.

I had considered brazing, but feel it would heat too much of the slide and destroy any heat treatment it might have had. Or just melt the discouraging alloy.

I hope I'll be able to return it for a refund. I got it for my brand-new daughter-in-law who really likes the Mosquito. Heck, with a refund, I could get her a new Firefly -- same pistol, same manufacturer.

Thank you,
Richard

 

[diverdon]

Sorry, I'm not that wealthy.

Sig did a lot of damage to there brand trying to make a quick buck on this. I've never seen anyone who has one purchase another Sig. Sorry I don't know anything useful that can be done with it.

 

[rg1911]

Sig did a lot of damage to there brand trying to make a quick buck on this. I've never seen anyone who has one purchase another Sig. Sorry I don't know anything useful that can be done with it.

As I mentioned in reply to another post, I got this because my daughter-in-law likes it. Having closely examined this pistol, I'm afraid I tend to agree with your evaluation. I'm just stuck with returning it if possible, or spending more money to fix it if, for whatever reason, the dealer won't accept its return.

Cheers,
Richard

 

[whatsupdoc]

Return it if you can and get a P226-22. .22 cal and uses a regular P226 frame.

 

[GH41]

As I mentioned in reply to another post, I got this because my daughter-in-law likes it. Having closely examined this pistol, I'm afraid I tend to agree with your evaluation. I'm just stuck with returning it if possible, or spending more money to fix it if, for whatever reason, the dealer won't accept its return.

Cheers,
Richard

If the seller won't refund your money I would also recommend throwing it away. I wouldn't spend money fixing something that might crack again next week. It is a very common problem.

 

[rg1911]

If the seller won't refund your money I would also recommend throwing it away. I wouldn't spend money fixing something that might crack again next week. It is a very common problem.

Throw it away. I'm apparently in the midst of a group of very wealthy people. Can I interest you in adopting me?

Cheers,
Richard

 

[Holliday]

Throw it away. I'm apparently in the midst of a group of very wealthy people. Can I interest you in adopting me?

Cheers,
Richard

Do a credit card charge back ASAP. Document everything and file a claim through gun broker. That is if the seller does not refund.

 

[rg1911]

'Fraid I paid by personal check. Shall see if the shop offers a refund. If not, I at least will file a complaint with Gunbroker, and possible the BBB.

Thank you,
Richard

 

[Holliday]

This was a shop? Hard to believe that they did not know it was damaged. That’s fraud. If they shipped it US Postal that’s mail fraud.

 

[rg1911]

This was a shop? Hard to believe that they did not know it was damaged. That’s fraud. If they shipped it US Postal that’s mail fraud.

Will see what the owner says on Monday.
I will say that the crack was not noticeable until the slide had been thoroughly cleaned. Until then, some old grease/dirt/powder had done a fine job of camouflaging it.
When you get right down it, if getting a refund fails, I may just keep the pistol and flog the heck out of it. The crack isn't through the slide; where it is shouldn't affect functioning at all.

Cheers,
Richard

 

[GH41]

Throw it away. I'm apparently in the midst of a group of very wealthy people. Can I interest you in adopting me?

Cheers,
Richard

I might be interested in adopting you. Do you do floors? Cook? My wife does neither and cost me a fortune! I'll tell you what.. I'll let you adopt her. For every week you keep her I'll buy you a Sig Mosquito as long as the supply last. That would be the best business deal I have ever made!!!

 

[Holliday]

Will see what the owner says on Monday.
I will say that the crack was not noticeable until the slide had been thoroughly cleaned. Until then, some old grease/dirt/powder had done a fine job of camouflaging it.
When you get right down it, if getting a refund fails, I may just keep the pistol and flog the heck out of it. The crack isn't through the slide; where it is shouldn't affect functioning at all.

Cheers,
Richard

Well let’s hope they just goes good on it, ?

 

[whatmeworry_45]

That repair would be a no-go even if the alloy was weldable. With a standard 50% de-rate due to heat input and HAZ, it would fail sooner than later. That's not even mentioning warping. AL loves to heat warp and shrink and pull all over the place.

 

[rg1911]

The Mosquito was shipped back today for a full refund (at least that's what the shop wrote).

Thanks for all the good information that convinced me to not mess with it.

Cheers,
Richard

 

[Tiger_Shilone]

Oh I forgot about that, whatmeworry is correct, aluminum loses around half it's strength when welded. That's why vehicles made out of aluminum are riveted together instead of welded seams. Welding is the process of taking your perfectly machined parts and destroying them with heat. Can't recall the number of parts I've destroyed through either heat-treat or welding ops after machining.

to the OP, good to hear they are making right on it.

 

[blcouch]

I had a Mozzie years back but sold it in favor of a threaded .22 conversion for my 226. As for welding, all that about aluminum losing half it’s strength when welded, that’s news to me and a lot if boat builders. Austal Shipbuilding builds aluminum welded high speed ferries and littoral combat ships for the navy. Also, a lot of Coonasses built welded aluminum boats that take quite a beating. I think riveted aluminum boats are in the weaker camp. I forgot who made the welded aluminum suppressor back about 8 years ago but if I recall it was pretty tough. Now a Mozzie slide is a different animal. Put it on a scrap heap with the early P22s.

 

[Tiger_Shilone]

As for welding, all that about aluminum losing half it’s strength when welded, that’s news to me and a lot if boat builders. Austal Shipbuilding builds aluminum welded high speed ferries and littoral combat ships for the navy. Also, a lot of Coonasses built welded aluminum boats that take quite a beating. I think riveted aluminum boats are in the weaker camp. I forgot who made the welded aluminum suppressor back about 8 years ago but if I recall it was pretty tough.

https://www.sciencedirect.com/science/article/pii/S2092678216302849 Pretty good paper describing alum welding with boat construction. Structural Allowances are made to make up for the loss of strength in the welded joints. Steel welds have much better bonding and crack resistance. Tempering and work hardening of alum materials gets tricky, it's all about the T state that you need when finished. you guys that weld aluminum my hat is off to you!

 

[hermosabeach]

Assuming Sig denies the warranty claim as you are not the original owner
Assuming the FFL and the shipper deny the claim-


Does the crack impact function? Can you drill the end of the crack to keep it from spreading and then repair when the budget allows?