Pipe Notch

[DWright]

stupid question, but does anyone have pics of a 60-66 with rear bags and just a pipe notch? (preferably aired out)

[DWright]

no one?

[baggedout81]

Get at shotbed,he welding some in his.I cant remember right off what size it was

http://67-72chevytrucks.com/vboard/s...=332884&page=9

[chevytrucknut]

Like this one?
[IMG][/IMG]

[DWright]

exactly what i was was looking for, got any side pics aired out?

[60apache]

Originally Posted by chevytrucknut

Like this one?
[IMG][/IMG]

did you build that yourself

[chevytrucknut]

The notch was done by my friend Dan at Sick Industries. Its simple and works great. The cross member in front of the rear end has a small notch in it too to clear the rear end when air'd out. I had to raise the bed floor 2 inches to clear also.
[IMG][/IMG]

[CHIZZLER]

Nice truck i just got my truck back from dan. He cut the frame down and the bed. He does killer work.

[chevytrucknut]

Originally Posted by danny piscitelli

Nice truck i just got my truck back from dan. He cut the frame down and the bed. He does killer work.

Thanks, Yes Dan does great work.


Your right dropped spindles and dropped lower control arms. I may take one of the two out and see how it sits. I think it is too much drop. The bags have to get 90% full to lift. Cross member lays out long before bags do.

[DWright]

Looks great. i assume you're running drop spindles in the front too? thats the hieght i was looking for in the rear, thanks for the pics.

[shortbed70]

Heres my pipe notch welded in

[Chris65GMC]

I did a search, but does anyone have a link for a good 'how to" on the pipe notch?

[hothues70]

I've always just unbolted the rear hangers or coils and let the truck down on the axle to get my mark. Easiest way for me to figure out where to cut. Then just measure how much farther you have to go to reach the lowest point, laid out or wherever and cut ur piece of pipe to give you that much notch. Trace it on the frame, cut it out and weld it. It goes pretty quick that way. Has for me anyway.

[Chris65GMC]

Originally Posted by hothues70

I've always just unbolted the rear hangers or coils and let the truck down on the axle to get my mark. Easiest way for me to figure out where to cut. Then just measure how much farther you have to go to reach the lowest point, laid out or wherever and cut ur piece of pipe to give you that much notch. Trace it on the frame, cut it out and weld it. It goes pretty quick that way. Has for me anyway.

Whats the best pipe to use? Size / Wall? Do they sell non-galvanized pipe at home depot and such?

[protrash64]

lakeroadster; with out going into a complete engineering seminar, how do you make that calculation? Just curious.

[SCOTI]

Originally Posted by protrash64

lakeroadster; with out going into a complete engineering seminar, how do you make that calculation? Just curious.

x2?

Also.... What if a pipe notch similar to what is pictured above is boxed on the inside? What effect would that have to restore that strength?

[shortbed70]

My notch I used .25 wall tubing and then used 1/4"x2" plate and welded on top of the notch to top of frame. Nothing fancy but it works.

[daverod]

Thanks for the time to figure this out John. I knew you just were'nt talking $hit. I even kinda understand it. Minus all the numbers and stuff.

[protrash64]

Ok, thanks John.........that's cool!! Now my question is what is the difference from boxing to '' heavy structural steel members that are added to the existing frame rail.''?

Isnt that just the same as boxing on the outside of the frame? And, do the bolt holes reduce the section modulus of the frame?

[protrash64]

We may have to start paying consultation fees soon!!!

[protrash64]

Originally Posted by lakeroadster

As for the bolt holes, they don't effect the strength very much as long as they are spaced away from each other.

I guess to make a more extreme example, using the 4.75'' frame rail from page 1 (d).....what if, centered on the frame rail, one was to holesaw a 3'' hole thru the frame. What does this do?

My father was an engineer at Caterpillar for 40+ years so I'm used to physics, equations, and math blowing holes in my 'common sense'.

[darkhorse970]

Originally Posted by lakeroadster

Yep, from a "calculation standpoint" adding the structural steel member is about the same as welding in a boxing plate. Most of the bolt on kits use a steel plate that is considerably thicker than the stock truck frame thickness. That helps but I still would like to run the numbers on one of the kits to see if it is as strong as the original uncut frame when all is said and done.

As for the bolt holes, they don't effect the strength very much as long as they are spaced away from each other.

I took a little time this morning and made a solid model using Inventor Cad software. (See attachments below)

First I made a model of a stock frame rail.

Second a model of a c-notched rail using 4 inch pipe (0.237 wall) as the notch. This configuration is about 75% weeker than the stock frame.

Third was the c-notch with a 1/4" thick boxing plate. This configuration is about 25% weeker than the stock frame.

Using FEA is more realistic than the simple channel and tube calculations that were discussed in the previous posts because it looks at how all the parts work together as a system. And the cool thing about this type of analysis is it gives you a warm fuzzy feeling about how different modifications effect the strength of a part.

Kind of neat, don't ya think?

This is very nteresting reading...

John, did you run the numbers on an "off the shelf notch"? (I wanted to attach a pic of the one I have from Early Classic Enterprises, but can't find it on their site now) I'm very curious to see how this stacks up the to other designs shown here.

I have not installed it because I decided that it probably wasn't necessary on my '63. I was thinking about using it on my '68, but I'm not sure if thats a good idea or not now.

[SCOTI]

Originally Posted by daverod

Thanks for the time to figure this out John. I knew you just were'nt talking $hit. I even kinda understand it. Minus all the numbers and stuff.

Agree 100%. I would also like to add....

Originally Posted by lakeroadster

Just trying to help.... don't shoot the messenger

There's a difference when someone criticizes a modification and/or method w/o providing the benefit of their logic on how things are affected. 'Just because' as reasoning is when people grow irritated. We can all learn from each others backrounds, educations, & experiences throughout our years.

I did consider the strength impact when reducing the height of my frame channel. I figured the use of the heavier walled material (.250" steel plate c-notch) w/boxing it in (using .1875" steel plate) would restore the majority of the strength. Seeing those numbers crunched, I'm going to re-evaluate/scrutinize my set-up & consider the possibility of plating the outer wall of my frame for additional assurance.

[DWright]

Keep the pics commin' guys! i've decided that a pipe notch is all i need for what i want. i got the pipe Wednesday and will probably start in on it this tuesday night. i'll try to take some pics to show progress. from the pics it looks as though i'll get plenty of drop with a pipe notch. thanks again guys.

[sailed2japan]

Without detailed engineering experiments and only sense to work with. I would say that by notching half the height of the frame, using the same grade/thickness steel, and boxing the back side, to include going a distance equal to the height of the frame forward and aft of the notch, ther would be little to no degredation of the integrity of the frame. And lets face it, if you're notching your frame, you're not planning on heavy duty work.

Oh, and the gas tank behind the axle? Really? Even a topped off 40 gal tank only weights about 300lb!