Peterbilt 359 'needle nose' conversion

[robdebie]

On 5/11/2024 at 11:02 AM, Force said:

I have many pictures of the 1673 in my files since I started gathering when I found out the truck had one of them engines.
On many places it say that the truck had a 1674 but that's not true according to my reliable source, he say it was a 1673 due to age of the engines...the 1673, 1673A and 1673B was made 1960-1968 and the 1674 came on the market 1967...the movie was from 1971 and the engine was allready old and worn by then wich a 4 year old engine wouldn't have been...and the yellow air cleaner used wich was a 4 inch intake tube 1673 air cleaner, the 1674 used a 5 inch intake tube and a different looking air cleaner...so in conclution he says the engine must have been a 1673B.
Here is a link to my reference files for the 1673 https://public.fotki.com/ForceFC1/cat-1673d333/ , feel free to use them.

On this picture you see the missmatched wheels too, 5 hole steelies on the drive axle and 5 hole Alcoas on the rear tag axle as this is the passenger side, the other way around on the drivers side.
The suspension is hidden by the wheels most of the time so it's hard to see, and yes it's the beam you see highlighted in this picture and when you know how a Page & Page suspension looks like it's very clear.
Here is a truck chassis with that suspension.

Thanks for the engine reference file link! We/you/I would need dimensioned drawings like the one below from your collection before a 3D CAD drawing is a possibility. But I gues you don't have this brochure yourself?

I'll stop doubting the Page & Page rear suspension, and order that Czech set ?

Rob

[Force]

On 5/20/2024 at 5:28 PM, robdebie said:

Thanks for the engine reference file link! We/you/I would need dimensioned drawings like the one below from your collection before a 3D CAD drawing is a possibility. But I gues you don't have this brochure yourself?

I'll stop doubting the Page & Page rear suspension, and order that Czech set ?

Rob

No I don't, the images was found on internet.
The 1673C is a redesign and is slightly different from the 1673 and 1673B and the 1673C appearently developed to the 3306.
These are the only dimensions I have found so far.

[robdebie]

Here's a follow-up on the 'needle nose' conversion. It took a few attempts to get the grille printed correctly. The first parts shown on page 1 had many problems. The next print is shown on the left of the photo below. The louvers were made 0.45 mm thick instead of 0.3 mm, and still look thin enough to my eye. Each louver had about eight print supports. But I forgot to add supports to the frame above the louvers, so that came out deformed. Another problem that kept coming back were 'dog ears' at the bottom of each printed part. The next print was perfect! I added extra supports at the 'dog ear' corners, and that solved the problem 95%. A bit of sanding solved the remaining 5%. That part of the conversion is done, next is the hood. I will do a 3D design of that part too.

Rob

 

[peteski]

Very nice.  Could you post a rendering of the successful grille with the supports on it? While I don't do any 3D printing, I'm always open to learning how others succeed in printing some amazing objects.  There is a lot of science and even maybe art (and multiple  tries) involved in successful 3D printing.

[robdebie]

Peteski, that is an excellent question. I had to learn a thing or two on the subject of supports before the part came out right (out of the printer of a club member).

I added the supports manually, because automatically generated supports did not yield good prints. It's my own interpretation of what was required, and I went for 'safe' regarding the thin louvers, giving them 10+ supports each. The overall result was a true forrest of supports. But that's mainly because this a strange part to print.

The part now printed near perfect, but it was difficult to get all the supports off. I worked my way down from the grille's top, and maybe spent half an hour. I had positioned the supports on the louvers such that I could get to them with a razor blade saw from the front (as you see in the picture). I would then snip away the supports from the rear side. Still I broke three louvers, but the breaks are so brittle that they fit perfectly back together, and could be glued invisibly with thin CA.

Rob

Edited July 5, 2024 by robdebie

[peteski]

Very interesting and educational Rob - thanks!

Also interesting that few of the louver supports appear that they aren't attached to the back edge of the louver, but in other places. Or maybe they are still attached to the rear edge but at a different angle?

[robdebie]

I don't have total control over the supports. In the software I'm using (PrusaSlicer), you put a small sphere where you want a support, and it has a cone that defines the direction of the support. But the rest is up to the software, and it sometimes has a mind of its own.

Rob

 

 

[peteski]

Thanks again for the demonstration. Now I see that the supports are not right on the thin edge of the slats, but a bit higher on the wide surface. I'm learning all sorts of things without owning the printer, or using the slicer or CAD software.

[robdebie]

Peteski, that sounds like how I learned how an Alps printer worked from you and others, some 20 years ago ?

One more comment is that the 'sphere and cone' markers are a bit misleading, the real supports are way bigger. In this case the real ones overlap the lower side and rear side of the louvers.

Please note that I'm very much a beginner with this, I started doing the supports maybe a month ago, and applied the new knowlegde to maybe 10 parts. I don't have a printer myself, a club member does the printing for me. But having control over the supports is a great plus, it improved the results a lot. And it saves the club member some time too.

Rob

Edited July 8, 2024 by robdebie