Anybody ever cut / shorten a Bullnose frame before?

[Rembrant]

Odd question I suppose, but has anybody ever turned a long wheel base truck into a short wheel base truck? What is it, 133" to 117"? Would it be as simple as cutting a 16" section out and then welding it back together? I haven't had an opportunity to look at both frames side by side.

I guess there's people swapping in Crown Vic front ends, so they must be welding a section of the car frame to the truck frame no?

Any comments from the been there, done that crowd?

[Gary Lewis]

Cory is chopping a section out of his frame, as explained here, and Jonathan/FordF834 has done it but, if I remember correctly, on a Supercab.

On the Crown Vics front ends, I did some Googling and found threads on various other forums where people have done this, and the names of those following the work include our FuzzFace2, so maybe Dave can comment?

[Rembrant]

Gary Lewis wrote

Cory is chopping a section out of his frame, as explained here, and Jonathan/FordF834 has done it but, if I remember correctly, on a Supercab.

Excellent. Thanks for the link Gary, I hadn't seen that one in a while. What I was curious about, and I guess that threads confirmed it, is if there is a nice straight section on the frames of the 133" wheel base trucks where the 16" can be removed, and then the two halves match up perfectly square for welding.

Going to go look at an '86 tomorrow...long bed of course, and was wondering how much work it would be to shorten it so that I could make use of the spare Flareside bed I have;).

Doesn't seem like too big a deal. As long as the difference is all between the back of the cab and the rear axle, then maybe it won't be too bad to remove and still keep it square.

Of course it all depends on how rusty this 133" truck is...

[Gary Lewis]

Make sure you don't miss Cory's note that he should have started 1" or so one way or the other to make it match perfectly.

[Ford F834]

I chopped my crew cab frame from a long bed down to a factory short bed length. I deleted exactly 16.0” just aft of the forward bed mounting holes. A regular cab or supercab should work equally well. There is a description of how I did it with pictures in my old build thread on FTE (look at post #7):

https://www.ford-trucks.com/forums/1451357-short-bed-4-door-diesel-project.html#post16549720

The part that I did not cover in that thread is the fish plate reinforcement of the welds. I have not done that yet. I asked Scott Miller about it at the 2017 show, and he recommended oblong plates with a hyperbolic shaped ends to diffuse the stress points as much as possible. The fish plates will be even more important on a 1/8” F150 frame compared to my 1/4” one-ton frame.

I may eventually do the same thing to my ‘81, but not any time soon since I am using it daily. It is also a Swiss cheese frame and will be more challenging if I decide to attempt it.

[Ford F834]

[Rembrant]

Ford F834 wrote

I chopped my crew cab frame from a long bed down to a factory short bed length. I deleted exactly 16.0” just aft of the forward bed mounting holes. A regular cab or supercab should work equally well. There is a description of how I did it with pictures in my old build thread on FTE (look at post #7):

https://www.ford-trucks.com/forums/1451357-short-bed-4-door-diesel-project.html#post16549720

I actually found your thread when I went looking after I posted the question here.
I saved the link for later viewing.

There's no reason a regular cab long box wouldn't be exactly the same. It looks like your cuts were so well placed that the stepside box dropped right on in the holes in the frame. That's cool.

I have no problem making the nice straight cuts, but something I thought of after the fact was, how did you make sure the cuts were in the exact same spots on both sides of the frame? Did you measure from a specific spot on each side? If you mentioned it in that thread, I missed it.

It may be a total wash in the end anyway if this truck is too rusty. Going to check it out tomorrow sometime, and if the frame is decent, I might grab it for shortening;).

Thanks guys!

[Gary Lewis]

Let us know what you decide.  

[Rembrant]

Gary Lewis wrote

Let us know what you decide.  

I'm deciding to not buy the truck, unless it becomes a whole lot cheaper, and even then...I doubt it.

I drove a little ways to see this thing, only to find out that the picture in the online ad was (I believe) from when the seller had purchased the truck several years before. Oh well.

Nothing fancy. 86 F150 2wd lwb, 300/6, NP435, and 3.08 open diff. It was pretty rough though.

Interesting side note, if Jonathan is still watching along, this truck did indeed have the factory EGR delete plate under the carb. This is the first truck I've found with one of these installed. Not sure if it has to do with the year, the region, or the truck (GVWR?). I looked at an 81 Bullnose with the 300/6, and it had a full EGR system, but that truck was an F100 Flareside.

Also, I thought the Bullnoses were all EFI in 86? Or was it only the 302? Or none at all and I'm out of my mind? This 86 was a non-catalyst, old school single carb, and DSII ignition.

[1986F150Six]

For the 49 state versions, F.I. came in 1987 for the 4.9L. I am not sure regarding the California trucks.

[Rembrant]

What years had the so-called "Swiss Cheese" frames? I guess they'd be more difficult to shorter eh? Or, not recommended at all...?

And, I hope this isn't too dumb a question, but how do you reply in a thread without directly replying to a specific post? Does that make any sense?

[Ford F834]

Swiss cheese were only 80/81, and from what folks have reported the late 81’s did not have the holes.

That is a good point about the reply function, the way it’s structured there does not seem to be a way to generically reply to the thread other than replying to the very first post.

[Rembrant]

Ford F834 wrote

Swiss cheese were only 80/81, and from what folks have reported the late 81’s did not have the holes.

Ok, that's what I thought. I'm casually looking for another project Bullnose, and an '81 popped up semi-locally. I call it "local", but it's far enough away I can't just drop by and have a look at it. The seller is sending me pictures of the frame today. Thanks Jon.

Cory

[Ford F834]

I have done a lot of measuring and checking on my ‘81 Swiss cheese frame, and I actually think the spacing of the holes would work out, and I think it could be shortened. That said, if you are on the shopping end of things, a solid frame would be an easier/better candidate.

[Rembrant]

Ford F834 wrote

I have done a lot of measuring and checking on my ‘81 Swiss cheese frame, and I actually think the spacing of the holes would work out, and I think it could be shortened. That said, if you are on the shopping end of things, a solid frame would be an easier/better candidate.

Are the Swiss cheese frames lighter/thinner than the later ones, or is the only difference that they're full of holes?

On the topic of frame shortening (Swiss cheese frame), what would stop a guy from filling the holes if they were in the way? You could have a steel disk cut, and then weld it into the hole to fill it.

Is that crazy talk? I really know nothing about the Swiss cheese frames.

[Gary Lewis]

I think they are the same thickness as the other frames.  However, there's no real advantage to filling the holes.  The way I-beams or C-channel works is that the web, the part in the middle, is there mainly to hold the upper and lower lips apart.  As long as the web is strong enough to do its job then holes don't matter.  And that's the case for those frames.

There's a guy on FTE that has a pulling truck with a swiss cheese frame.  Has used it in competition for years with no problems.

But, if you need the holes filled where you are cutting you could do that.  Or, fishplate over them.

[Rembrant]

Gary Lewis wrote

I think they are the same thickness as the other frames.  However, there's no real advantage to filling the holes.  

OK, gotcha Gary. I was only thinking of filling a hole if by chance you had the cut the frame and reattached it where there was a hole, that's all.

[Gary Lewis]

Understand.  You could just cover the hole with a larger fishplate.  But, you'd want to treat the original weld and the frame as you might get water in there.  And/or leave a weep hole in the bottom so water can get out.