Historic Truss Bridge Restored for Arena Replacement Bridge

June 22, 2014

Pictures by Bob Rodrigue, George Falardeau and Larry Gomes
Story by Larry Gomes
 

Our fourth, fifth, sixth and seventh trail work days of the season was one of the nicest stretches of weather that we have seen in a long time with dry, sunny days and cool nights.  We saw it coming a week out and decided this was the perfect time to restore the old Paris Road truss bridge that the club had purchased last year as a replacement for the bridge behind the Notre Dame Arena.

Research and Preparation

Of course no one in the club had ever restored a bridge before so we were not entirely sure how to go about it.  After asking for advice from many people we decided that we needed heavy duty sand blasting equipment.  We called Brian Ruel (the president of the Presidential Ranger Riders snowmobile club in Gorham) who also works for Pro-Quip rentals, and he set us up with a brand new heavy duty compressor and also let us use their in-house sand-blasting equipment.  Brian also gave excellent advice on what we needed for protective gear and what to use for blasting media.  We purchased a Tyvek work suit, a sand blast hood and a respirator.

Our Trail Master Bryan MacDonald was able to get a pallet load of Patriot Blast media from his employer (Sanel's) at a discount.  The blasting media is made from coal slag and it comes in 60lb bags and is commonly used for sandblasting old paint and rust off metal surfaces. 

Bryan had the pallet of blast media loaded onto his trailer on Wednesday afternoon and then headed over to the clubhouse where he met up with Matt Godbout.  Matt loaded one cement block and two steel beams onto Bryan's trailer and then loaded 3 more cement blocks into his dump truck and they headed off to the sand pit in Stark where the bridge was being stored.  Matt dumped out the cement blocks and they left Bryan's trailer parked next to the bridge.  The cement blocks and steel beams would be used later when the bridge was lifted off the ground.

Sand Blasting the Bridge

With all of the pieces in place, Larry arrived at Pro-Quip early on Thursday morning and picked up the compressor and sand blasting equipment.  He met up with WMRR club president Bob Rodrigue and they proceeded to set up the sand blasting equipment.  It took a few adjustments but by 10:00am the blasting was well underway. 

The blaster unit is called the "Texas Blaster" and it has a dish shaped bowl on top where you pour the blasting media.  The media goes down through a small 2" hole and fills the storage canister which can hold two 60lb bags.  Once the media has been poured in, you turn on the air compressor and pull up a rubber plug which blocks the fill hole and turn on the air.  The air pressure in the tank holds the rubber plug in place.  You then turn on the blast nozzle, point and shoot. 

The nice part about this unit is that it splits the air flow into two paths.  One path pressurizes the storage canister and the other path flows around the tank directly to the blast nozzle.  The trick is to introduce just enough pressure into the canister to push out the blast media.  Too much pressure wastes the media and not enough pressure yields too little media and therefore no results.  The remaining air is routed through the blasting hose at high pressure so that it propels the media at high speed.  Once the unit was adjusted, you could keep the nozzle moving at a slow but steady pace peeling off a 3" wide swath of paint and rust. 

Once in a while the unit would clog.  At that point, you need to increase the pressure going into the storage canister and push out the clog then set the valve back to its optimum operating position.  It took about 20-30 minutes to run through the blast media in the storage canister.  Once the media runs out, you turn off the air to the canister and turn off the compressor, reload and do it all over again.

Every couple of hours, the clear plastic window in front of the sand blast hood would get too dull to see out of so the old window would be taken out and a new window slid in.  Even though the weather was dry and cool and the wind was blowing, wearing the protective clothing was hot.  The Tyvek suit builds up heat and so does the hood.  It was common for the plastic window to fog up.  The only solution was to roll up part of the hood which let in some flying debris.  By the end of the day, it felt like we had taken a bath in sand.

All day Thursday, Bob loaded the blaster while Larry sand blasted and by the end of the day, we had gone through 34 bags of media and we were just over halfway done with only six bags left.  So we put in a call to Bryan to get another 30 bags ready for the next day.

On Friday, Larry went to Sanel's and picked up Bryan's truck that had the 30 bags of media already loaded in it and then went to Labonvilles to pick up some 1/2 chain that would be used to lift the bridge.  When he got back to the bridge site, Dalton Binette was there ready to run the equipment and the blasting continued.  By lunch time, the entire top of the bridge was done. 

Lifting and Painting the Bridge

Dalton and Larry rigged up the chains and Harley Mason arrived with his son and another helper with a large front end loader and a skid steer.  While the loader lifted the bridge, the skid steer picked up the cement blocks and moved them into position.  Then some wooden blocks were put on top and the bridge was lowered onto the blocks giving about 2 1/2 feet of clearance under the bridge.  Once the bridge was lifted, sand blasting continued and was finally completed around noon on Saturday. 

After lunch on Saturday, George Falardeau, our club Treasurer was next to arrive.  George had heard about my plan to hand paint the bridge and decided that was going to take way too long.

He brought with him a brand-new airless paint sprayer capable of spraying a gallon of paint in 3 minutes!  Once this was set up and running, it was pretty clear this was the right decision.  It took just over 4 hours to paint the entire bridge, which would have been a 2-3 day job if we were painting by hand.  Not only was the gun fast, it put on a coat of paint that was thicker than a hand brushed coat.

The only problem was I had underestimated the paint so by late afternoon on Saturday, we had run out of primer.  Luckily the Home Depot in Littleton had what we needed on hand so after a Saturday night trip, we were well supplied with paint to finish the job on Sunday.  Here are some pictures from the four-day project:



The brand new air compressor from ProQuip is attached to the "Texas Blaster"  You pour two bags of blast media in the top,
start the compressor and then turn on some valves on the blaster and away you go.  There was also a water separator that had to be
emptied periodically.  Luckily it was dry weather, so we only had a few clogs.  But we could see that in humid weather, it would have been
impossible to do this job.

 

Club president Bob Rodrigue was in charge of running the equipment and loading it with blast media.  By the end of Thursday, he
had loaded over a ton of blast media into the machine.

 

Assistant Trail Master Larry Gomes dressed in Tyvek work clothes, wearing a respirator and protective blasting hood
works his way along the bridge blasting off old paint and rust.
 

Because the bridge was resting on the ground, Larry was able to use a short step ladder to reach the top of the bridge.

 

The club arc welder and cutting torches were brought up to the site on Thursday afternoon so repairs could be made to the bridge.

 

The battery on the arc welder was not holding a charge and nobody had jumper cables but  club member Pete Peare did not miss a beat
and took the battery out of his own truck and got the welder started.

 

Groomer operator Shaun Roy gets started welding some broken angle iron which was holding up the center beams.

 

Shaun then moved on to welding two cross braces that will keep the sides of the bridge steady when it is being lifted.
After the bridge has been moved to its new location, these cross braces will be removed.

 

Pete used the torch to cut some old railings off the bridge, then he got to work cutting holes in the steel beams so that stringers
can be bolted to the beams and a deck installed once the bridge is in place over the Dead River.

 



On Friday, Dalton Binette spent the morning loading blast material into the sand blaster.  He then helped to get the chains
set up for the bridge lift.
 

Two steel beams are chained in place ready for the lift. Two more longer chains were then wrapped around these beams
and used to lift the bridge onto concrete blocks.
 

This big loader had no problem lifting the bridge.  The bridge weighs about 4 tons, so the lift on one end was only about 4,000lbs.

 

The skid steer uses its bucket to clear away debris to make room for the last cement block.  Both pieces of equipment were
donated by Mason Enterprises in Milan.

 



This new paint sprayer is now owned by the club.  It's light weight and portable but it does the work of 5 painters.

 

George starts spraying the primer coat on the bridge.  While he was doing that, Larry was busy preparing the next gallon of paint.
The sprayer can output 1/3 gallon of paint per minute so it did not take long for it to run through a gallon.

 

Larry used his sand blast hood to  paint the bottom beams.  It offered more protection when he was under the beams looking up.
The hard hat built into the hood also came in handy when crawling under the beams.

 



By 11:00am on Sunday, the primer coat was done.

 



George switched over to the Hunter Green Rust-O-Leum paint and started the finish coat.

 

By 3:00pm on Sunday, the final coat was done.

 

Compare this picture with the one below to appreciate how far this project came in just four days...

--- PROJECT STATISTICS ---
Bridge Length: 45' 6"
Bridge Width: 13' 8"
Truss Type: Parallel Chord Pratt Truss
Weight: 8,000lbs (apx.)
Surface Area: 1,400sf (apx.)
Blasting Time (includes loading media): 14 hours
Compressor Run Time: 10.5 hours
Blast Media Used: 67 bags @ 60lbs/bag
Painting Time: 4 hours per coat
Primer: 7 gallons
Finish Coat: 7 gallons

Our sincere thanks go out to all the volunteers who participated in this project.  We are very fortunate to have some extremely talented members who are able to bring their expertise  projects like this.  This was a great example of a group effort where many ideas were brought to the project by different people to create a timely and efficient solution.  It's fun to be part of a team that can think on its feet and try different things to get the job done. 

Our next big challenge is figuring out how to build the abutments that will hold the bridge in place over the Dead River.  If you know something about rebar and concrete and would like to help with that phase of the project, please contact larry@twolakeslodge.com     Our goal is to have this bridge in place by Labor Day so we will be working on this project in July and August.

To see some background info on this historic bridge, click HERE.

To see pictures of the bridge installation at its new site, click HERE.
To see a front page story about this bridge in The Berlin Reporter, click HERE.

 

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