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  #11  
Old 04-23-2021, 05:52 PM
crystallographic crystallographic is offline
MetalShaper of the Month October '14 , April '16, July 2020
 
Join Date: Dec 2010
Location: Western Sierra Nevadas, Badger Hill, CA
Posts: 3,693
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Hi Paloma,
Sorry to take so long responding ....
Thank you for your purchase of the Meco torch.
(I still like using this little torch .... once in a great while I try something different - no joy!)

Let's see what I can fill the blanks of "not success" with ....

Here are some answers for you:

I have seen hundred of video and bought dvds galore. I watch folxs that lay in tack super quick and easy. I can not get a simple tack with out filler rod to save my life.
I am working with .063 3003 H14 aluminum. The torch chart says to go up to a N3 tip. I can make it super hot and my heat zone is the entire coupon it seems like. The coupons are 4x8 inch.

Yes - the coupons get Too Hot. I like using 10in by 3in, and X2 the heat soak is about equal to the amount it radiates, so "cooler" in practice.
BUT - I have demonstrated in public many times - using a cutting torch to weld 3X6in coupons with.

Huge flame = go like Hell.

Quick like a roo - or a jumbuck ...

When I watch videos Kent talks of 3-5 torch lengths of flame. Are we talking about the inner cone or the oxygen feather?
Only the inner cone.
P1060469cc.jpg
P1060467 c.jpg
I want to believe we are talking the inner cone, as a large feather washes backwards when I am close to the plate. (YES)

I can not seem to build heat up with this inner tip unless I get almost carburizing like flame. Just off feather takes a long time to do the tack like I witness in the videos and all the super experienced people.
I use one cone length of feather, just enough to soften the cone tip.
But the tip size for the .063 has to be a good size.


After using the N3 tip and trying over and over again is has turned black. Is this normal (yes smart guys I know heat and coloring) my question is a I trying to get it to hot.

Yes, going over and over the same spot makes it dark and nasty. After 2nd try and fail - THrow Away + Start Fresh.

(Hint: take that full weld sample you show, scrub it well with isopropyl and ss brush, brush a coat of flux on both sides of the weld and just make a "go-over pass" with the torch - No Filler. And use this pass to practice your 45deg angle, distance from metal, and even swirl/oscillate/figure8 the flame path a bit, or just a basic "forth and back."

Melt it all nice and smooth.

Wipe clean and give it an eyeball. )

I donít feel like I have the pinpoint control I see peoples having.
That pinpoint control will come later, when the other primary skills are solid.

Thanks for helping a woman out in a man heavy industry. My goal is I would like to incorporate more compound curves for some art projects.
My joy to assist.

Here is a shot of my first few attempts of a full weld.
This was done with the N2 tip I was not just melting with this, however it seemed slower than the old pros.


Tip size #2? On our weld chart we show a #3 for the .063. But if you DO use the #2 the pressure Must go UP. Increased pressures drive the puddle downwards, thinning the puddle, only hastening to blow holes.

RE: SPEED. Oh sigh - both rough AND slow?

ACCURACY FIRST. Try what I suggested.

ssssspeed second.
Otherwise you just arrive at your own wreck faster.


AND -**** Remember what the US Aluminum Association teaches in their epic book, "Aluminum Welding, Theory and Practice" (early edition) : "Aluminum MUST be clean for welding. Scrub weld path, both sides and the edge, with a clean solvent (99% isopropyl) using a stainless scrub pad or brush. The aluminum surface must be Bright silver, not gray."****


(Maybe this little "skill tune-up" might help you. .... )
Women were trained by the thousands to weld aluminum in WW2. Took 6 hours on average, before they went out in the shop and started welding airplane partsl for Northrop, Lockheed, Boeing, Stearman, Waco, Piper, Vought, Hughes, Beech, (and a few others that slip the chip) ... USA built 330,000 airplanes in 3.5 years. Some wooden ones early in the fight changing to aluminum mid- and end. TIG only invented in Nov. 1942 - for magnesium welding - fewer fires from fewer torches being used.)


I see varying abilities come through my workshops. Many learn in 6 hours. Some get worse because of self-imposed tensions. Some become very good in the first 6 hours ever welding at all. I never can guess.

So, maybe a little you might not have seen in your searching yet ....?
:::
P51, tip tackwelds c.jpg
P51, tipwelds c.jpg
P51, tipweld, final.jpg
FACTORY Gas Weld, Swift wingtip, 5052alloy, 1953vtg..jpg
P51-C wingroot fairing, FACTORY hydrogen weld.jpg
acet weld, 3003alloy, .050in.thick, hammered shape, Meco weld.jpg
C195 wheelpants, shaped sections welded into halves. 3003alloy, 050in.thick..jpg
P38 duct , FACTORY weld,.jpg


....Good luck,
Success and Joy,
__________________
Kent

http://www.tinmantech.com

"All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919.

Last edited by crystallographic; 04-26-2021 at 01:46 AM.
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  #12  
Old 04-25-2021, 04:36 PM
Ducatichica Ducatichica is offline
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Join Date: Aug 2020
Location: Seattle
Posts: 5
Default Feeling better

Thank you all again
The larger coupons is definitely helping. I am getting the concept of gas and burning a bit better.
First is my best attempt a filler less tacking. The second is me just deciding my hands at making more holes. I think I get the ideas of when I am getting to hot and too cold.

My thoughts are to continue practicing heat control till I tack on demand
Then I can worry about the heat control on my welding
I believe my heat on tacking to slow or to close. I make a lot of kisses on my attempts
If I can gauge the lightness of the heat to just blow those two pieces of liquid together. I tend to heat on side or other then make kisses.

94A6F7AE-D3F5-4AAD-9C06-B161EACBDC1D.jpg

BF82D1B8-AD15-44F9-93EC-CA49EC587C1A.jpg

70F9C2CF-5294-4FC8-9BA2-59A31761BDA7.jpg
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Paloma
Making magic at times

Last edited by galooph; 04-26-2021 at 02:43 AM.
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  #13  
Old 04-25-2021, 09:40 PM
crystallographic crystallographic is offline
MetalShaper of the Month October '14 , April '16, July 2020
 
Join Date: Dec 2010
Location: Western Sierra Nevadas, Badger Hill, CA
Posts: 3,693
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Quote:
Originally Posted by Ducatichica View Post
Thank you all again
The larger coupons is definitely helping. I am getting the concept of gas and burning a bit better.
First is my best attempt a filler less tacking. The second is me just deciding my hands at making more holes. I think I get the ideas of when I am getting to hot and too cold.

My thoughts are to continue practicing heat control till I tack on demand
Then I can worry about the heat control on my welding
I believe my heat on tacking to slow or to close. I make a lot of kisses on my attempts
If I can gauge the lightness of the heat to just blow those two pieces of liquid together. I tend to heat on side or other then make kisses.

Hi Paloma,
Yes, larger coupon.
Steady hands ... one hand can support the other. Or, I use a smooth wood broom handle to support my wrists. Parallel to my front. Above the work. Slide along to get the feel of it. Maybe some wax. Then - weld.
Practice, practice .... then tacks come on demand. (but- metal has to touch... molten metal cannot levitate across gaps.)
Max heat is when torch is vertical to the metal and right on it = max heat. Then as the torch angles, the heat glances off....heat goes down.
Last, left-right. But on center is equal heat. Hard to see, but move quick when one side melts first. This is a quick fast process. Get ready, get on top, and your welds can only get better.


(Your welds are looking better.)
__________________
Kent

http://www.tinmantech.com

"All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919.
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  #14  
Old 04-26-2021, 04:40 AM
skintkarter skintkarter is offline
MetalShaper of the Month Nov. 2018, Jan. 2021
 
Join Date: Feb 2013
Location: Auckland New Zealand
Posts: 787
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Paloma, second everything that Kent has said.

Did you have a look at the Ken Barton video? See how he manipulates one half of the panel when tacking and 'walks' it towards the other half, torch passing side to side to preheat and drive flux into the join.

When I did my practice coupons, I had one side clamped to the bench, a loosish clamp on one end and then started to tack a couple of inches in (watch Kent's videos re this). Once the first tack was done, then wait for the panel to cool and the join to pull together. As it comes together a couple of inches from the first tack, preheat as per before and then close in to form the tack, oscillating and varying the distance of the torch as required.

Very much as I said earlier with tig welding where I preheat both parts and bap the pedal.
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"I know nothing. I from Barcelona" (Manuel - Fawlty Towers)
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  #15  
Old 04-28-2021, 04:38 PM
Ducatichica Ducatichica is offline
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Join Date: Aug 2020
Location: Seattle
Posts: 5
Default Thanks for all the fish

Kent thank you for the #4 tip I received the other day.
I used it a bit and it gave me a good sense of high heat low volume.
I went an switched back to the number three and I think my tacking turned out rather well. I could hear the clicking in my brain
https://www.allmetalshaping.com/atta...1&d=1619645799
https://www.allmetalshaping.com/atta...1&d=1619645799

6916AE6D-D6B8-428E-8CDA-BA20BDEFDDEF.jpg

D9C28248-B69C-4FE3-88F3-A0DD36E8E37D.jpg

7A2FF6BC-1B65-49C0-BAF1-A4F6BCD0FC9A.jpg
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Paloma
Making magic at times

Last edited by galooph; 04-29-2021 at 02:41 AM.
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  #16  
Old 04-30-2021, 03:19 PM
crystallographic crystallographic is offline
MetalShaper of the Month October '14 , April '16, July 2020
 
Join Date: Dec 2010
Location: Western Sierra Nevadas, Badger Hill, CA
Posts: 3,693
Default

Quote:
Originally Posted by Ducatichica View Post
Kent thank you for the #4 tip I received the other day.
I used it a bit and it gave me a good sense of high heat low volume.
I went an switched back to the number three and I think my tacking turned out rather well. I could hear the clicking in my brain
https://www.allmetalshaping.com/atta...1&d=1619645799
https://www.allmetalshaping.com/atta...1&d=1619645799

Attachment 59773

Attachment 59774

Attachment 59775

Hi Paloma,
Your work is looking smoother and more confidence is showing.
Glad you got the #4 tip. Big soft flame is helpful.


Re: Tacking:
There are two basic - and very different - situations that require two different tacking approaches.
One - the parts are jigged, clamped, fixed together and the edges fit perfectly. For this you can tack with either no filler or with filler. Production parts are done this way, one after the next.



Two - The panels are simply held in space and you have to hold one against the other and tack them any way you can. This is how we put car bodies together, large sculptures, large airplane cowling parts, etc. Sometimes I will weld a little blob or nugget onto one edge, every two inches or so. Then I flux these and hold the panels together and fuse where they touch....Boom, tacked.

Drawback is that any movement in the held panel at all right after tacking and the weld cracks.

Weld must be held still for 15 seconds, until it has solidified enough for strength.
Many times just 5 or 6 tacks will hold well enough to get a skip weld (short welds that are only 1-2 inches long) or three on there to really hold well. Then from there it is much easier to pull the edges into alignment and tack on ahead as you progress along the long seam.
On larger panels it is hard to get perfect fits, so working the seam with hammer and dolly as your weld progresses can help a lot.
(On big jobs the welds can sometimes be 6 - 8 - 10 feet long.)



Example of a "big job" follows:
(some welds are 5 -6 -7ft long ... 3003, .050" thick)
GT40 door tacked _Geo.jpg
P1170372 c GT40 rear deck fit for tacking.jpg
P1170266 rkw welds tacked panel GT40.jpg
If you look closely you can see the tacks are about 1.5in apart - standard distance on long welds.

P1170386c GT40 rear deck welded.jpg
P1170395 GT40 rear deck weld partly planished c.jpg
P1170397c planishing welds on rear deck, GT40.jpg
GT40 rear clip welded and planished.jpg
P1170255 c GT40 wheel arch weld.jpg
P1110509 cGT40 body finished bare aluminum, ready for chassis mounting.jpg
__________________
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http://www.tinmantech.com

"All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919.
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