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Here is a link to the Volvo body builders manuals (the guide book truck equipment manufacturers/engineers would refer to for configuring/changing a Volvo truck). 

Volvo Body Builder Manual 

For frame stuff scroll down and click on Section 7 Frame and start reading, yes a lot of the stuff is pretty technical but they list welding procedures, etc.

This manual has all sorts of technical info on VN series trucks (wiring, air system, suspension, fuel systems, etc).

Every truck modification shop is going to have their own way of doing it and they will always tell you that their way is the best and they have never had a problem doing it their way, so you have to take it with a grain of salt. I personally wouldn't do a z-cut or any cut that has sharp corners in it as those corners are going to create stress risers (spots where stresses are higher due to not being evenly distributed).

Edited by porky69

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Not exactly, but the truck came with very little of the frame rails left just behind the rear brace so that was all we had to work with, so we had to improvise.

D8eiCREl.jpg

w6ksT6dl.jpg

sDn8pA1l.jpg

This was the plan and here's the "execution". First deal with the stubby frame "leftovers". Note the "precision" leveling of the frame rails for cutting and eventual welding of the frame rail extensions.

h0IRvk1l.jpg

Mark the blanks per the design drawing for cutting, heating, bending, tacking and welding.

IJCs2DKl.jpg

Tacked up parts, incidentally the blanks were made from A35 steel sheet plate (1/4 inch thick) and bent on a brake.

3K7mmYVl.jpg

Extensions welded on. Note that we welded on a temporary brace on the extensions while we were screwing around with the bumper and the bumper frame structure.

RQG7ELPl.jpg

Finished product.

Xxp2wmnl.jpg

ldIdEukl.jpg

 

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5 hours ago, porky69 said:

Here is a link to the Volvo body builders manuals (the guide book truck equipment manufacturers/engineers would refer to for configuring/changing a Volvo truck). 

Volvo Body Builder Manual 

For frame stuff scroll down and click on Section 7 Frame and start reading, yes a lot of the stuff is pretty technical but they list welding procedures, etc.

This manual has all sorts of technical info on VN series trucks (wiring, air system, suspension, fuel systems, etc).

Every truck modification shop is going to have their own way of doing it and they will always tell you that their way is the best and they have never had a problem doing it their way, so you have to take it with a grain of salt. I personally wouldn't do a z-cut or any cut that has sharp corners in it as those corners are going to create stress risers (spots where stresses are higher due to not being evenly distributed).

Gee that's funny I printed that manual out 80 some pages worth maybe I should take a closer look at it. I am going at this progect with idea that if I sell this truck some body might use it for what it was designed for and put something heavy on it. maybe over kill for hauling a rv but thinking of the day I have to sell it. Got to keep my options open

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6 hours ago, phoenix2013 said:

Not exactly, but the truck came with very little of the frame rails left just behind the rear brace so that was all we had to work with, so we had to improvise.

D8eiCREl.jpg

w6ksT6dl.jpg

sDn8pA1l.jpg

This was the plan and here's the "execution". First deal with the stubby frame "leftovers". Note the "precision" leveling of the frame rails for cutting and eventual welding of the frame rail extensions.

h0IRvk1l.jpg

Mark the blanks per the design drawing for cutting, heating, bending, tacking and welding.

IJCs2DKl.jpg

Tacked up parts, incidentally the blanks were made from A35 steel sheet plate (1/4 inch thick) and bent on a brake.

3K7mmYVl.jpg

Extensions welded on. Note that we welded on a temporary brace on the extensions while we were screwing around with the bumper and the bumper frame structure.

RQG7ELPl.jpg

Finished product.

Xxp2wmnl.jpg

ldIdEukl.jpg

 

Can i make this z cut with a plasma cutter?

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4 hours ago, runaway parents said:

Can i make this z cut with a plasma cutter?

We used gas torch. I suppose plasma would work if it had the ball to do it. lot of them are for sheet metal. Both sides were V grooved and welded on both sides. We did not fish plate. We did not grind the welds except in couple of small areas on the inside of the rails where things needed to be flush.

Edited by phoenix2013

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I have a plasma that is supposed to cut up to 3/8 of an inch planning to use a liner and to use it as a backer plate and burn the welding rod into it just like I would do when performing a weld test should work fine .also planning to bevel all weld surfaces. liner will also be bolted. do you think this will work ? maybe over kill but that's the way I am when in doubt build it stout.

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You mentioned on the other thread 3 feet straight and the 6 feet down for beaver tail. Are you adding 3 feet plus 6 feet for a total of 9 feet, or is it 6 feet total?

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Following....    I have a Northern Tool plasma cutter and needed a shape cut in 1/4".  Between the air pressure and the rated power it really struggled.  It was quicker to just get it close and grind the rest.

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11 hours ago, phoenix2013 said:

You mentioned on the other thread 3 feet straight and the 6 feet down for beaver tail. Are you adding 3 feet plus 6 feet for a total of 9 feet, or is it 6 feet total?

Total lineal ft of frame that I need is 9 ft because of the rake of the dove tail I am not actually adding a lot of length to the truck. Don't know if this makes any sense. But it is the only way I can explain it

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That is a lot of rail,. I would use tempered steel (either new or used for "donor" frame). do a long "z" cut to weld them together, fishplate the joint and add at least one brace between the extended rails.

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10 hours ago, phoenix2013 said:

That is a lot of rail,. I would use tempered steel (either new or used for "donor" frame). do a long "z" cut to weld them together, fishplate the joint and add at least one brace between the extended rails.

copy that will do thanks

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5 hours ago, GlennWest said:

Why 7018 over tig. I would never put a stick rod to it if  had tig.

Glen the 7018 was easier to fill and cap the weld. I ran split pass on the cap as it was over an inch wide with double bevel and gap. Just came down to convenience. Besides my little dry torch would have got a serious workout running that much weld continuous for the 2 frame rails. 

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1 hour ago, tyates007 said:

Glen the 7018 was easier to fill and cap the weld. I ran split pass on the cap as it was over an inch wide with double bevel and gap. Just came down to convenience. Besides my little dry torch would have got a serious workout running that much weld continuous for the 2 frame rails. 

B-U2a weld? 3/8 root with 30 deg bevel or 1/4 with a 45 degree? By the way, agree with the 7018 lo-hy rod for structural welding but was curious on your prep. Also wondering if you left your backer bar on the weld or if you arc gouged it off.

David

Edited by GeorgiaHybrid

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10 hours ago, GeorgiaHybrid said:

B-U2a weld? 3/8 root with 30 deg bevel or 1/4 with a 45 degree? By the way, agree with the 7018 lo-hy rod for structural welding but was curious on your prep. Also wondering if you left your backer bar on the weld or if you arc gouged it off.

David

Wow, understood none of that but sounds interesting.  You guys are way too smart for us normal earthlings 😁

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17 minutes ago, SuiteSuccess said:

Wow, understood none of that but sounds interesting.  You guys are way too smart for us normal earthlings 😁

"Are you using 220?"  "Yeah, 220 or 221, whatever works."

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15 hours ago, GeorgiaHybrid said:

B-U2a weld? 3/8 root with 30 deg bevel or 1/4 with a 45 degree? By the way, agree with the 7018 lo-hy rod for structural welding but was curious on your prep. Also wondering if you left your backer bar on the weld or if you arc gouged it off.

David

I left the backer strip on. There was no harm with it being left on. I ran it hot enough that it was mostly consumed. Everyone has their own way. This worked well for me. I am not a professional welder but can hold my own with tig and stick. Never been a huge fan or great with mig but most of my mig experience has been short arc in high production welding which is what I did through college working for Icon. 

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8 hours ago, SuiteSuccess said:

Wow, understood none of that but sounds interesting.  You guys are way too smart for us normal earthlings 😁

LOL, Carl just short hand welding talk, not any different than what some doctors have done talking about what my issues were.

For a B-U2a weld, the "B" indicates a butt joint which is just 2 parts butted into each other (instead of a T or corner). The U means the base metal can be an unlimited thickness, 2 indicates a single V grove (just one side is prepped, not near side and far side)and the "a" indicates a SMAW weld process (Shielded Manual Arc Weld), otherwise known as stick welding.

The parts have a gap (called the root opening) that is left open at the bottom of the "V" to be welded to make sure the weld fully penetrates the base metal. To have something to weld against, you add a small bar (1/8 to 1/4 in thickness and 1 to 1.5 inches wide) to put a "bottom" in the weld called a backer bar. The sides are then ground to give you a bevel shaped like a "V" to fully weld the two pieces together. That gap and grove angle are specified depending on the weld. In this particular weld, you could use a 1/4" root opening with a 45 degree groove angle,  a 3/8" root opening with a 30 degree groove angle or a 1/2" root opening with a 20 degree groove angle.

That weld, done in that manner with the correct electrodes and settings will give you a B-U2a Full penetration weld as per the AWS D1.1 manual. I live by that manual doing the work we do. I have learned to not look at the welds on RV's anymore, they just give me heartburn.

Edited by GeorgiaHybrid

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Just a stupid butt weld. That is all we do. We just don't use a backing strip. Can understand you using it though. Easier.

Edited by GlennWest

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Glenn, you might be one hell of a pipe welder but a butt weld, groove weld, J weld and others in the AWS have very specific requirements and uses. A "stupid butt weld" is limited in thickness and must have a backer bar or backer weld to be a pre-qualified full penetration weld.

Without a backer bar or weld, it is a simple, partial penetration weld with limited strength.

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