42 Pilot Model HUP Project

[Andrew]

omg that made me laugh, now i know what to say when someone points out something about my halftrack

Originally Posted by RHClarke

Comments/observations and constructive criticism will of course be welcomed. If you don't like what you see and you want to comment to that effect, feel free to send your comments along with the money to make things right.

[RHClarke]

I finally felt good enough to visit the barn on Saturday. It was great to see Bob and Grant. Bob had not been feeling well lately, but he made the effort to join us at the barn for a chin wag and then to go to lunch. We sure hope he gets back in to "fighting form" as the glaciers are starting to recede, and spring is just around the corner (although it may be more than a little frozen).

The objects of my attention were the front fenders that fit on the body of the Pilot Model. The upper ends of the fenders were heavily rusted and had to be replaced. A quick zip with a thin bladed grinder wheel took care of the offending rust. Two replacement blanks were then cut out and fitted to the ends of the fenders.

I 'gorilla" welded the blanks from the inside of the fender, and then carefully tack welded the exterior where they joined the fender. After a morning of tacking and grinding, one fender was finished. After lunch, I tackled the other fender. Next step is to fit them to the truck body and test for fit. I am sure that there will be some adjustments made, and after that is done, I will drill the holes and pack them away until our date with the sandblaster this summer.

Pics:

1 - one of the culprits
2 - rust - the enemy!
3 - out with the old
4 - inside view
5 - awaiting fit testing and drilling

[RHClarke]

Saturday at the barn was spent removing the two axles from the Pilot Model frame. The weather was rainy in the morning, but sunny and hot in the afternoon. The perfect weather for taking apart a CMP, and for the emergence of the local air forces. Blackflies, gnats and mosquitoes made their debut at the barn on this fine day. Bob was away on family business, and Grant was at work, so the only company I had were the birds and the bugs.

The removal of the spring assemblies from the frame went quite well. The front axle had screw in spring mounting pins, while the rear axle had friction fit spring mounting pins. The pins for the springs were very worn, as would be expected from 70 years plus of use. I then removed the pin assemblies and then propped up the frame. This allowed me to roll the axle assemblies out from beneath the frame.

The springs were liberated from the axle tubes with the help of the air impact wrench and lots of penetrating oils. They were in fair shape with no cracks visible on the individual leafs. The axle tubes were in great shape as one would expect with such a robust design.

The rest of the day was spent preparing a site for another sea container, which should be in place this summer. It will be the Pilot Model's home for the foreseeable future.

Photos:

1 - Front axle off
2 - '45 frame - count the crossmembers to compare with the '42
3 - '42 frame for comparison
4 - '42 rear axle with post war parking brake assemblies

[RHClarke]

The front and rear spring assemblies were the focus of my most recent activities. All four springs were disassembled and while there was some wear evident, there were no cracks visible. Some of the individual spring leafs had lost a few degrees of arc, but I don't think that re-arching will be necessary.

Next the shocks were inspected. The two rear shocks had no resistance and the arm rotated from stop to stop with a clunk. The arms on the shocks were different from others I had in stock, so they were salvaged. This involved cutting between the shock arm and the shock body. The arms were then heated by torch and the center stud was punched out. We tried to remove the shock arms with our press, but got no movement whatsoever. The shock arms are pressed on to a finely splined shaft, which has a remarkable amount of surface area that builds up a lot of resistance over the years from use and rust. This left the drastic action of destroying two otherwise non-serviceable shock bodies. We will salvage everything that can be reused, but both bodies are now trash.

Two spare shock bodies had their arms removed and will now serve as replacements for the originals. The arms came off quite easily once a grinder with a thin blade cut down to the splined stud. A few taps with a punch and hammer later, the replacement shocks were put on a shelf to await re-assembly.

The down links were trashed but are being used as samples in our search for single headed links. The links in the back are 13.5 inches from the top of the housing to the end of the threads. The ones in the front are an inch shorter. It has been a fruitless search for replacements thus far, but the guys at Malmberg Trucks in Ottawa are on the case.

The next step was to do a bit of sandblasting to clean up the suspension parts. This went fairly well, but was both hot and exhausting work. The temperature approached 30oC and the dark hood for the sandblasting served to heat things up significantly. Probably a cool day for our Aussie friends, but blistering hot for those of us who live in the Great White North.

After sandblasting, the parts were treated with phosphate spray and left to dry. A few minutes later, they were ready for a quick scuffing and then paint. There will be another small sandblasting session in the near future, and a major industrial level session later this month if things work out. I plan to bring in a local company that has the capability to blast all day long. We have a few frames and loads of parts that we want to prepare for reassembly in the fall.

Photos:

1- Shock arm and stud - note the fine splines
2- Post sandblasting and phosphate treatment
3- New paint

[RHClarke]

The big push today was to refinish/refurbish the Pilot Model components. The overarching priority for me is to get the 45 HUP on the road and safetied before the new Ontario safety standards come into effect this summer. The issue being that the new safety is much more involved and detailed. http://www.autotrader.ca/newsfeature...2JQDJtXcY4V.97 It apparently relies on the mechanic inspecting components and measuring them to compare with the written standard for an individual vehicle. The problem is that there is no written standard for most CMPs. So to avoid future complications, I have been working on the newer HUP during most of the visits to the barn to prepare it for the safety inspection.

When it gets too cold outside - like today, my attention goes back the Pilot Model. The hub refurbishing process is the same as the other HUP hubs but this time I decided to totally take down the hubs to its components. The inner grease cups were removed this time to see how they were fitted. After the studs and spacers were punched out, the cup (a ring, actually that kept grease away from the brake shoes etc...) came off with not too much of a fight. The remnants of a gasket can be seen in the attached photo.

The day was spent cleaning off the gasket and the accumulated dirt, grease, oil and paint from the hubs. This was completed with a wire brush on the angle grinder, some picks, a screwdriver, a scraper and some very potent cleaning fluid. After cleaning, the hubs were treated to a phosphate shower and allowed to dry. Paint was added just before departure this afternoon.

I was going to sandblast the hubs, but this is not the season for that type of fun. The wire brush did a fairly good job, but it was tedious work. Good thing we love this hobby.

Photos:

1 - The spin ring/cup
2 - Ring and hub
3 - First coat of paint

[Phil Waterman]

Hi

Having just read the link on the new standards, sounds like a move to get a lot if not all cars over 10 years old off the road, but that's not the topic of this thread.

The point is getting your vehicle past with least hassle, you point out they have nothing to measure your HUP against. But you do have bench mark to measure the quality and in depth nature of your restoration, your photos and the narrative you have posted on MLU. While you are wise to get your vehicle registered prior to the rule changes, I would not be too afraid of the standards.

Keep up the good work and the careful documentation of the restoration process.

Cheers Phil

[RHClarke]

The inside of the Pilot Model hub includes a grease cup that is designed to prevent grease and other contaminants from spotting or staining the brake mechanism that is covered by the hub. This cup employs a thin gasket to assist it in carrying out its function.

When I removed the cups (or rings if you prefer) the OEM gasket were destroyed having been either glued down or having adhered to the two mating surfaces over its several decades of use. This necessitated making new gaskets. Fortunately, Bob had a roll of paper that he had acquired a few years back that had a similar texture to the original gasket, but also had a finished inside coating. He explained that it was a waterproof membrane and that the paper was used to wrap bundles of map making paper. In any case, it was the perfect replacement for the gaskets.

The cups provided the template for cutting and the bolt holes were a perfect match for the large hole punch that we have at the barn. Two gaskets were knocked out in quick time.


After coating both sides with silicon gel, the gaskets were laid inside the hubs with the cups and the bolts were re-installed.


One had to be careful to make sure that the splines on the bolts meshed with the cut outs inside the bolt holes and that all of the bolts threads were similar in direction - as these hubs are side dependant. After a few gentle taps with the hammer and a wooden block, most of the bolts seated nicely. The heads of the bolts secured the cups and gaskets nicely.


The hubs were then turned over and the spacers installed. I used the wheel nuts to press the spacers into place and this also served to seat those bolts that didn't seat previously.


Next project: the other two hubs.

[RHClarke]

I got the hubs and brake shoes back from the brake shop. They did a great job of milling down the hubs and in putting new material on the brake shoes. They didn't have to match the linings to the hubs as the fit was great from the start.

This past weekend was nice and warm - perfect for leisurely activities such as sandblasting and painting. Up for treatment were the frame, transmission, and transfer case. The two axles will be done at a later date.

Photos:
1 - Sandblasting pit - bare frame
2 - Frame - painted
3 - Tranny
4 - Transfer case

[RHClarke]

The temperature this morning was absolutely wonderful. Warm and dry enough to sandblast away years of paint and road dirt from the Pilot Model axles. It took two pots (four bags of grit) to do both axles. It helped that they were given a good going over with the wire brush and then washed with gasoline before sandblasting.

We noted with some amusement that the CMP metal seems to turn a shade of Airforce blue when sandblasted. I noted that the colour (rust red) the metal turns later must be from embarrassment...

After the initial blasting, care was taken to search out grease deposits that only seem to get revealed after blasting. Once scrubbed and washed, the whole axle gets a phosphorus treatment. Then comes the paint - or bug attractant, as we at the barn call it.

I have had great success with Tremclad rust paint over the years, and despite the ever increasing price of the stuff, I will continue to use it. My choice of finish for the first coat is gloss black. Given time and temperature, it binds with the exposed metal nicely, and if left outside to cure overnight, it will repel raindrops without running. It is also easy to clean before adding the green paint.

This ends the frame and drivetrain portion of this project - next step is reassembly, followed by a lot of welding on the body and roof. The engine can wait until later on.

[RHClarke]

You can count the number of rain free days this "summer" at the Hammond Barn on one hand. The weather has a heavy influence on productivity anywhere, but Ottawa seems to embrace the extreme: too hot/wet in summer, too cold/wet in winter, too wet in the springtime, leaving only autumn as the only somewhat dry/cool/reduced bug period where work really gets done. That said, this past week has been somewhat autumn-like with a good breeze blowing. Perfect Pilot Model work weather. Finally!

This stage of the refurbishing project has transitioned into the rebuild stage. The rear floor component of the truck is too far gone to restore. The only saveable piece is the curved section at the rear. So, the rear portion was removed from the front. This involved removing eight floor screws that secured the driver/pax station floor to the rear portion cross member. Then the frame had to be cut on both sides, freeing up the components.

I knew that the underside had lots of salt damage and had to cut some of the hat channel out for replacement. Once the hat channel was opened, it was evident that there was more damage on the inside of the channel than what we could see from the outside. Bob's learned opinion was that it would be impossible to weld new sections in. Reluctantly, I concurred and decided that the whole rear component (less the rear curved supporting channel) had to be replaced.

Photos:
1- Floor components joined
2- Side panels removed
3- Front nose - in surprisingly good shape!
4- Post surgery

[Alex van de Wetering]

Rob,

Excellent to see you're back to work on the Pilot HUP!
Pity there is so much rust damage to the underside...but good to hear you guys decided to fix this properly.

Alex

[RHClarke]

I got some time today to further disassemble the Pilot Model cab front. There were three floor plates to remove and none of the screws/nuts wanted to turn out. One cold chisel and a good-sized hammer convinced them to part company. I was pleasantly pleased to see that the plates and the frame that support them were in pretty good condition. Rust for sure, but nothing compared to the rear of the floor. I will get the frame sandblasted sometime in the future.

Just for fun, I pulled the Pilot Model fuel tanks out to determine their condition. As expected, the driver side fuel tank had a fairly corroded bottom end. After a quick exterior clean up (wire brush, scraper), it was time to check the interior. There was a bit of rust - see last photo.

Photos:
1- The plates
2- The frame
3- Orange fog

[RHClarke]

A banner day today - I had the cab front, floor plates, nose/front clip, side pillars, bush guard, grill, bumper, and fuel tanks sandblasted. The chap who does this work has a great set up - drive in, drop the goodies and drive out. Turn around time was less than a full day. Sure, it cost more to have a pro do the dirty deed, but in the end, the reduced cost in sweat, toil and tears makes it worth the cost.

While the kit was being denuded, I peeled the skin of one of the side panels just to determine the extent of rust damage. It was not a pleasant sight, but on the bright side I get the feeling that my welding ability (no skill) will improve over this coming long, bleak, cold winter.

Photos:
1- Side panels - one stripped
2- Rust! Bottom of the pax side panel near the wheel well
3- More Rust! Bottom of the pax side panel nearest the rear door

[RHClarke]

With the sandblasted items back at the barn, painting was the order of the day. Fortunately, it was another nice day. It started off a bit cool (7oC), but it warmed up by noon to 17oC with a good breeze to keep the bugs at bay. Using a HVLP spray gun, the first coat was applied by 9:30 AM. The second coat was applied after lunch. The aggressive media used by the sandblaster left the metal with a rough texture, but the primer coats took some of the roughness down. The final coat of green paint should even things out, but that is a task for another day in the future.

Photos:
1 - Before shot 1
2 - Before shot 2
3 - After shot 1
4 - After shot 2

[Phil Waterman]

Looks like you have been making real progress. With a lot more part replication, look forward to seeing the finish product.

Cheers Phil