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5 minutes ago, vincen47 said:

This is a really great thread, lots of very detailed and useful information. No one has mentioned it so far in this thread, but if I remember correctly, the AMT kit’s headlights are too high up on the cab. I haven’t located the thread, but I think some people have corrected that error on their models.

You seem to be right, I'm looking at my reference truck pictures and it does appear to be higher than they should be. As far as the thread goes, I am actually very impressed with all the small details that have been covered here. I didn't find any thread that was very detailed on the Freightliner trucks. I also just purchased a brochure of the 1971 Freightliner cabovers. I will post the pictures on here for more information. I not only wanted my questions answered, I wanted to have a nicely detailed thread about Freightliners for anyone who needs it. I am really enjoying the learning process before I get very serious on my build, it will help a lot in the final product.

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33 minutes ago, Muncie said:

Freightliner claimed the only "clyclomatic" dual action cab tilt pump.  The pump worked when the handle was moved in both directions so it actually tilted the can fairly quickly - like Brain said, not terribly fast or slow.   Once you got past 45 degrees, the weight of the cab would finish the tilt. There is a small valve, the thing sticking out with a crosspin above the cyclomatic valve, that controls up or down.

The horizontal location in the photo is more correct than the vertical position in the AMT kit. But it needs to be far enough ahead of a fuel tank bracket so the tilt pimp handle doesn't hit the fuel tank brkt. 

I will deffinatly be sure to pay attention to that detail when it comes around that part of the build. I also plan to do some "plumbing" and I was wondering what you guys suggest for air lines, electrical lines, and hydraulic lines?

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1 minute ago, TheSDTrucker said:

I will deffinatly be sure to pay attention to that detail when it comes around that part of the build. I also plan to do some "plumbing" and I was wondering what you guys suggest for air lines, electrical lines, and hydraulic lines?

Fuel lines were cotton covered wirebraid - probably something available at Hobby Lobby or Michaels with close to the right texture. maybe braided fishing line dyed black...  painted in the chassis up to the engine.  Production probably varied at the fuel tank end - some unpainted, some painted to the fitting on the tank. 

The compressor discharge line to the chassis was copper tube or optional cotton covered wire braid.  This line has a lot of heat in it so it would be unpainted on the engine, and painted in the chassis..

Chassis air lines are nylon tube installed before chassis paint at the Portland TMP - may have been different at other plants.  Could be plain wire or standard model detailing wire, something that will take paint to represent the smooth nylon tubing.  The air lines from the relay valves to the brake chambers are cotton covered wire braid - also chassis painted.

The lines to the chassis mounted oil filter were also cotton covered wire braid.  This filter was required with Cummins engines but rarely specced with DDE engines.

what did I miss?

Let's leave this open for more model material suggestions.

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29 minutes ago, Muncie said:

Fuel lines were cotton covered wirebraid - probably something available at Hobby Lobby or Michaels with close to the right texture. maybe braided fishing line dyed black...  painted in the chassis up to the engine.  Production probably varied at the fuel tank end - some unpainted, some painted to the fitting on the tank. 

The compressor discharge line to the chassis was copper tube or optional cotton covered wire braid.  This line has a lot of heat in it so it would be unpainted on the engine, and painted in the chassis..

Chassis air lines are nylon tube installed before chassis paint at the Portland TMP - may have been different at other plants.  Could be plain wire or standard model detailing wire, something that will take paint to represent the smooth nylon tubing.  The air lines from the relay valves to the brake chambers are cotton covered wire braid - also chassis painted.

The lines to the chassis mounted oil filter were also cotton covered wire braid.  This filter was required with Cummins engines but rarely specced with DDE engines.

what did I miss?

Let's leave this open for more model material suggestions.

That is a great list of materials that I'll look for. I'm in town today so I'll check out Hobby Lobby. As for the external oil filter, are you referring to the Luberfiner?

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2 minutes ago, TheSDTrucker said:

That is a great list of materials that I'll look for. I'm in town today so I'll check out Hobby Lobby. As for the external oil filter, are you referring to the Luberfiner?

yes, referring to the Luberfiner  - required by Cummins, available for other engines - DDE had engine mounted oil filters similar to large automotive spin on filters.  I hope you are confirming some of this on your reference truck  - most of this is as clear as yesterday but time has taken a few memory cells.

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12 minutes ago, Muncie said:

yes, referring to the Luberfiner  - required by Cummins, available for other engines - DDE had engine mounted oil filters similar to large automotive spin on filters.  I hope you are confirming some of this on your reference truck  - most of this is as clear as yesterday but time has taken a few memory cells.

The reference truck does not have the Luberfiner. I have been making a few trips over to the truck to confirm the details, and so far everything had been spot on. As for the Luberfiner on the kit, I'll probably just file off the mold where it mounts on the frame in the kit. If someone were to instal the Luberfiner, would the oil lines just lead from where they would have originally been if it was a screw on filter? Or was it an entirely different location?

Edited by TheSDTrucker
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15 hours ago, TheSDTrucker said:

Here is a nice comparison for the headlights. Real truck vs the model. There is a noticeable height difference.

20180102_173327.jpg

AMTPK6118Freightl-vi.jpg

The Lights need to come down to where the top of the headlight  bezel  is level with the wheel openings....

Go to Tim Ahlborn's site to get correction instructions.....

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11 minutes ago, Jim B said:

Tim Ahlborn still has a site?  I haven't seen anything from him in years.

 

40 minutes ago, michaelbaskett said:

The Lights need to come down to where the top of the headlight  bezel  is level with the wheel openings....

Go to Tim Ahlborn's site to get correction instructions.....

He does have a website, and it appears that he has been active as he just posted a "2017 in review" photo album. As for the instructions, I may not be looking hard enough but I cannot find them

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12 hours ago, TheSDTrucker said:

 

He does have a website, and it appears that he has been active as he just posted a "2017 in review" photo album. As for the instructions, I may not be looking hard enough but I cannot find them

Tim is also a big part of the facebook page "model truck disscusion  group"

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On 1/3/2018 at 4:30 PM, Muncie said:

 I might cut that center panel out, leave the side panels so the sleeper curtain is open.

I actually have a new plan for my interior. It will still be the burgundy brougham color, but I am going to use real leather for the tunnel, curtain, and door panels. I'm going to use a couple leatherworking techniques I know to make the diamond pattern design the truck has. I never did find a good picture of the interior, but did the ceiling have the diamond pattern too?

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4 hours ago, TheSDTrucker said:

I actually have a new plan for my interior. It will still be the burgundy brougham color, but I am going to use real leather for the tunnel, curtain, and door panels. I'm going to use a couple leatherworking techniques I know to make the diamond pattern design the truck has. I never did find a good picture of the interior, but did the ceiling have the diamond pattern too?

the cab roof was also upholstered with the diamond pattern - the roof beam across the cab was painted - I believe it was painted the exterior cab color, but may have been black. - 

Leather sounds cool - but don't fall in love with it if it doesn't work out - leather can be difficult to make look to scale.  The real trucks weren't that nice...

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4 hours ago, TheSDTrucker said:

from another kitWhat was this blue knob for that sits next to the truck and trailer brake of all these older trucks?

20180106_105557.jpg

you're going to be sorry that you asked, because I don't know (I forgot) and don't have a simple answer...

if you can find a copy of the Bendix Air Brake Handbook, it's the best air brake reference out there.  Everything for the brake valves and air brake controls are there.  Get one as old as you can find so it has the single air brake system.  Dual air brake systems with front brakes became standard in the mid 1970's to comply with new regulations in (Federal Motor Vehicle Safety Standard) FMVSS 111.  The handbook is probably out there on the internet.  An original Freightliner owners manual would also have operating information.

The brake system in the AMT Freightliner kit is kind of an oddball - it has brake chambers set up for wedge brakes instead of cam brakes.  Wedge brakes were very rare - basically only CF used them.  Wedge brakes supposedly had better lining life - CF liked them. The first issue of the AMT single drive day cab kit was made to represent a CF tractor - It was incorrect in other ways because they came up with the sleeper cab dual drive from the same basic puzzle - so there is a mixture of CF components in the dual drive and vice-versa - and a lot of the specific CF stuff was left off.  That's my story about wedge brakes in the AMT dual drive kit.  Most dual drive tractors in 1971-1973 had cam brakes and were not built with front brakes - so I think the front brakes also carried over from the single drive CF kit.  If I built one of these, I'd delete the front brakes and switch it over to brake chambers from another kit for cam brakes.  

sometimes I get on the soapbox and can't stop...Hope this helps and isn't too confusing - 

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2 hours ago, Muncie said:

you're going to be sorry that you asked, because I don't know (I forgot) and don't have a simple answer...

if you can find a copy of the Bendix Air Brake Handbook, it's the best air brake reference out there.  Everything for the brake valves and air brake controls are there.  Get one as old as you can find so it has the single air brake system.  Dual air brake systems with front brakes became standard in the mid 1970's to comply with new regulations in (Federal Motor Vehicle Safety Standard) FMVSS 111.  The handbook is probably out there on the internet.  An original Freightliner owners manual would also have operating information.

The brake system in the AMT Freightliner kit is kind of an oddball - it has brake chambers set up for wedge brakes instead of cam brakes.  Wedge brakes were very rare - basically only CF used them.  Wedge brakes supposedly had better lining life - CF liked them. The first issue of the AMT single drive day cab kit was made to represent a CF tractor - It was incorrect in other ways because they came up with the sleeper cab dual drive from the same basic puzzle - so there is a mixture of CF components in the dual drive and vice-versa - and a lot of the specific CF stuff was left off.  That's my story about wedge brakes in the AMT dual drive kit.  Most dual drive tractors in 1971-1973 had cam brakes and were not built with front brakes - so I think the front brakes also carried over from the single drive CF kit.  If I built one of these, I'd delete the front brakes and switch it over to brake chambers from another kit for cam brakes.  

sometimes I get on the soapbox and can't stop...Hope this helps and isn't too confusing - 

 

The information you post is not confusing me at all, I actually really like reading your information. I really appreciate your contribution to this forum with all of your great answers.

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2 hours ago, DRIPTROIT 71 said:

Blue valve is tractor only parking brake.

Wedge brakes were not a favorite of most, but was found on other trucks. The company that I used to work for had a former Matlack R model with wedge brakes.

 

2 hours ago, Muncie said:

The brake system in the AMT Freightliner kit is kind of an oddball - it has brake chambers set up for wedge brakes instead of cam brakes.  Wedge brakes were very rare - basically only CF used them.  Wedge brakes supposedly had better lining life - CF liked them. The first issue of the AMT single drive day cab kit was made to represent a CF tractor - It was incorrect in other ways because they came up with the sleeper cab dual drive from the same basic puzzle - so there is a mixture of CF components in the dual drive and vice-versa - and a lot of the specific CF stuff was left off.  That's my story about wedge brakes in the AMT dual drive kit.  Most dual drive tractors in 1971-1973 had cam brakes and were not built with front brakes - so I think the front brakes also carried over from the single drive CF kit.  If I built one of these, I'd delete the front brakes and switch it over to brake chambers from another kit for cam brakes.  

What is the difference between cam brakes and wedge brakes?

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52 minutes ago, TheSDTrucker said:

 

What is the difference between cam brakes and wedge brakes?

An automotive hydraulic brake system uses a hydraulic cylinder to push the brake shoes into the drum.  Cam air brakes use a rotating S-shaped cam to move the shoes.  In wedge air brakes, the brake chambers push triangular wedges at the end of the shoes to move the lining into the drum. 

S-cam brakes - the cam is the s-shaped part on the right side of this picture.  Normally (what I've seen), the brakes are installed with the cam at the top.  The slack adjuster is a lever that rotates the cam.  The brake chamber attaches to the other end of the slack adjuster and is mounted on a bracket to the axle housing.  When air is applied to the service brake chamber, the cam rotates and pushes the linings into the drum.  (when air is released from the parking brakes, the spring in the parking brake chamber applies the brakes).  

ReliningProcedure.jpgSee the source image

         

Wedge brakes - there are a few more parts involved.  Basically, a wedge is pushed against the end of the shoes to move the linings into the drum.  This diagram shows the orientation of the service brake on the axles - two wedges, two brake chambers per brake.  The brake chamber tube is almost perpendicular to the brakes so it pushes against the wedge.

See the source imageSee the source imageSee the source imageSee the source image

 

Note, in my search for diagrams I found another great thread on AMT Freightliner questions - Brian (Driptroit) and others have posted some good information - unfortunately, photobucket has done some serious damage over there but still worth a good look.  http://hankstruckforum.com/htforum/index.php?topic=62775.30

This is a cutaway of the brake chamber with for the service brake and parking brake with no parking or service brakes applied.  As-shown, air has been released from the service brake side, air pressure is applied to the spring brake chamber to compress the spring and release the parking brake.  Most dual-drive truck-tractors have parking brakes on one rear axle and service brakes on both rear axles. 

See the source image

There are some youtube videos out there that have a lot more detail.

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1 hour ago, Muncie said:

An automotive hydraulic brake system uses a hydraulic cylinder to push the brake shoes into the drum.  Cam air brakes use a rotating S-shaped cam to move the shoes.  In wedge air brakes, the brake chambers push triangular wedges at the end of the shoes to move the lining into the drum. 

S-cam brakes - the cam is the s-shaped part on the right side of this picture.  Normally (what I've seen), the brakes are installed with the cam at the top.  The slack adjuster is a lever that rotates the cam.  The brake chamber attaches to the other end of the slack adjuster and is mounted on a bracket to the axle housing.  When air is applied to the service brake chamber, the cam rotates and pushes the linings into the drum.  (when air is released from the parking brakes, the spring in the parking brake chamber applies the brakes).  

ReliningProcedure.jpgSee the source image

         

Wedge brakes - there are a few more parts involved.  Basically, a wedge is pushed against the end of the shoes to move the linings into the drum.  This diagram shows the orientation of the service brake on the axles - two wedges, two brake chambers per brake.  The brake chamber tube is almost perpendicular to the brakes so it pushes against the wedge.

See the source imageSee the source imageSee the source imageSee the source image

 

Note, in my search for diagrams I found another great thread on AMT Freightliner questions - Brian (Driptroit) and others have posted some good information - unfortunately, photobucket has done some serious damage over there but still worth a good look.  http://hankstruckforum.com/htforum/index.php?topic=62775.30

This is a cutaway of the brake chamber with for the service brake and parking brake with no parking or service brakes applied.  As-shown, air has been released from the service brake side, air pressure is applied to the spring brake chamber to compress the spring and release the parking brake.  Most dual-drive truck-tractors have parking brakes on one rear axle and service brakes on both rear axles. 

See the source image

There are some youtube videos out there that have a lot more detail.

That is a very interesting system. I can see ways where it would be a pain, it appears to be slightly more complicated. I actually should go look at the brakes on that truck again, they appeared to look like what was in the kit

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On ‎1‎/‎5‎/‎2018 at 8:43 AM, TheSDTrucker said:

 

He does have a website, and it appears that he has been active as he just posted a "2017 in review" photo album. As for the instructions, I may not be looking hard enough but I cannot find them

You need to go to Tim's FOTKI site and check out his Freightliner photo's.....The first one shows his headlight corrections.....

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great looking brochure - there is a lot of good detail in the pictures

A couple of things to be aware of ---

As noted before, the AMT kit is a "raised" cab, it can be quickly identified by the vertical bar in the center of the grille.  The truck in the brochure is a "stretch" cab  quickly identified by the two vertical bars and important to note that it is 4 inches wider than the raised cab.  The extra width is in the center of the cab - engine tunnel, grille, radiator are among the affected areas where things are a little wider.

The front axle is an FE970 series axle with center point steering. Notice how the hub is thru the center of the wheel.   The steering kingpins are further into the wheel and vertical to reduce steering effort - kind of a poor man's power steering - not very common for general freight applications.

So, between the extra cab width and the narrower wheel track with center point steering, the front tires are located and appear to be much further inboard than the more common front axles used in general freight applications.  This is not a good picture for modifying the AMT front axle assembly to move the wheels inboard.

Farr Dynacell air cleaners with frontal air intake thru the nose skin like the AMT kit and the brochure were (probably?) not available with the 8V-71 engine.  The Farr air cleaner mounted easily on the inline Cummins engines but the main problem is that they didn't flow enough air to meet Detroit Diesel Engineering requirements.  I know for certain that it wasn't enough for the 8V-92's but at best they would have been marginal for the 8V-71 - maybe OK for the naturally aspirated 8V-71, but not for the 8V-71T - not sure about it on a 1971 to '73, but I'm sticking to it.  Some of the high horsepower 8V-92's that came later even required dual 16" diameter air cleaners - yeah, try to locate that where the trailer doesn't hit it.  I think your reference truck has stationary air intake with the air cleaner mounted on the exhaust cross braces - that would be correct for the 8V-71T.   The alternative with single exhaust is to frame rail mount the air cleaner under the cab ahead of the fuel tank.

Edited by Muncie
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