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tunnel stiffeners...

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AKSNOWRIDER

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Hi guys, well since we have snow and its about time to get the sleds out, I figured I better get the tunnel stiffners I made last season on..(I have a cabin 50 miles from the road, so when we go there we pull sleds with food, fuel, and clothes..none of the mountain sleds stock will hold up to the abuse of dragging a 300+ pd sled every weekend..so we reinforce them....) any way, this is what we run, hopefully this will give some of you more industrious guys some ideas..its not hard..just a little time consumming..so , having buckled my dragon tunnel twice(not pulling a sled either time by the way) I have a pretty good idea where the weak points are..on the pro..same as the dragon, you can buckle the tunnel with as little as 10 pds on the rear of it by simply landing something hard enough to bottom the suspension hard.. I am sure most of you have seen pics from last season where a few guys actually blew the stock brace off the tunnel..most would just install a slightly bigger bracket..oh say from the rear suspension mnt back to the bumper...and call it good..only to have it buckle the tunnel right in frt of the rear suspension mnts...(I know because thats what I did on the dragon after the first repair..it bent right in front of the new brace)...what I have done since then is brace the entire tunnel..from the frt mounts to the rear bumper..for the pro I decided to use 2 peices to acheive the desired strength....100" the full length of the tunnel and a honeycombed 3/16" brace that goes from the frt of the rear suspension mnt to the rear bumper(actually is the bracket for the bumper)..heres some pics to get the thought process going..1 side is fitted, am getting ready to start on the other side here in a bit...

first we get the sled up so we can pull the rear skid, drag the track out frt. between the ski's to give us room, and then remove the stock bumper, reflectors, unbolt the rail braces off the tunnel and then we fit the base tunnel brace...
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AKSNOWRIDER

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the stiffner, is cut out for the vin access as well as to recess our state tags(I have them little tags..they look like chit)....
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careful fiiting will improve both strength and the finished looks...
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once I have the fit how I want it I use cleco's to hold it while I drill all holes...
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next I over lay the rear brace and fit it....
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once I am completely happy with the fit, I will remove both peices, and transfer drill all holes to the peices for the other side..where I will repeat this whole proccess..once both sides are fitted ,drilled and clecoed, I will fit the rear bumper to both the sides and the tunnel top..
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from there will be disassembly, cleaning, final inspection before final assembly with solid rivits and glue(either lords(what polaris glues the sled with )or with 3M automotive glue)..that part will be coming soon if I can get off my butt and get back to work....
 
A
Jan 30, 2011
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Palmer AK
What is the gauge of the aluminum (or is it Stainless) of the stiffiner and the back bracket? I have a cabin at Fish Lakes and need to do exactly what you have done.
 

AKSNOWRIDER

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What is the gauge of the aluminum (or is it Stainless) of the stiffiner and the back bracket? I have a cabin at Fish Lakes and need to do exactly what you have done.
these are aluminum,.100 for the black peice and 3/16 for the silver peice...I can make them out of any thickness, but by the time you cut all the holes in it they dont weigh much..total for these with a bunch of solid rivits before powdercoat was about 12 pds..
 
A
Jan 30, 2011
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Palmer AK
these are aluminum,.100 for the black peice and 3/16 for the silver peice...I can make them out of any thickness, but by the time you cut all the holes in it they dont weigh much..total for these with a bunch of solid rivits before powdercoat was about 12 pds..


Sorry if I am a pain but I will be doing this, I see the weight as a small price to pay for a straight tunnel and being able to tow it I need it.

Did you paint or powder coat?
All rivets or do you use any small machine screws/ nylocks?
How about glue, do you use that or have you tried it?
 
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MORSNO

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Awesome fab skills! I may be talking to you about a set for my 07 Dragon, I pull a ice fishing house sled on Lake Louise and 25 miles out to Crosswinds lake (big lakers rule!)...just a little east/southeast from your back country cabin.
 

AKSNOWRIDER

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no pain at all , thats why I did the thread so others can see what is possible...I do use glue, either lords adhesive(what polaris uses on the chassis) or 3M panel adhesive(what most car manufacturers use to assemle cars now days)the lords is physically stronger..but the 3M is cheap, readily available, and way stronger then what the aluminum will take..rivit wise I use solid aluminum aircraft rivits(the fancy rivits that hold planes togeather), they are cheap, easy to use and way more durable then pop rivits or screws...plus on the off chance they ever do loosen up..simple re stike them and they tighten right back up..I powdercoat everything..including the rivits..here is a pic of my old dragon..I made running boards on it as well..

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AKSNOWRIDER

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Awesome fab skills! I may be talking to you about a set for my 07 Dragon, I pull a ice fishing house sled on Lake Louise and 25 miles out to Crosswinds lake (big lakers rule!)...just a little east/southeast from your back country cabin.
not a problem...let me know....
 

AKSNOWRIDER

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Well, got the other side fitted,now on to the bumper....

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I drill and tap the bumper for a single 3/8 stainless bolt, then pop both side panels off after determining where the bumper lines up, and drill the bumper hole thru all 4 layers...
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Reinstall the sides with the bumper and will leave the two holes in the rear panel to drill until final assembly..parts are ready to be taken off, cleaned good, and start final assembly.....I still need to build the tow hitch to bolt to the center plate on the bumper but thats easy enough to do...

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One thing I did notice and would advise all owners to check..is I found the track rubbing on the left rear suspension bracket in the tunnel..funny thing is both track tension and alignment have been and are spot on the moneyso I will be spacing the rear suspension mnt when I put the skid back in...
 

AKSNOWRIDER

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Now if I could only talk you into building me a set for my Dragon Mikey.
I would be happy to dave..how heavy duty and how fancy do you want to get?honestly, anyone who is even slightly mechanically inclined can do these...I use poster board to make my pattern, run it thru a flatbed scanner and load it on my buddies cnc waterjet..test fit the cut peices, send them out for powdercoat and then install them...hard part is just figuring out how much/little material is needed where to end up with as light but as strong of a tunnel as you need..if I didnt pull heavy sleds..I would go way lighter on materials and way fancier..
 

AKSNOWRIDER

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Ok, have had a few peeps wonder about some of the tools I use..so heres what I use..for holding stuff in place while fitting I use cleco's..a very simple tool and not very expensive...that make all sorts of them, what I use the most are 1/8", 3/16" and 1/4" as well as their panel clamps...a kit with pliers and 20 or so cleco's last time I bought some was like 40 bucks..and they will last several lifetimes...

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now for the rivits..I use a airhammer and the apropriate sized driver for the size rivits I am using,
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this is the tool used for bucking the rivits,, it is held against the backside of the rivit while the air hammer pounds and flattens the rivit against it..I have several i=of these..this one is what I use about 99.9% of the time..it just flat works very good...
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for rivits the sky is the limit, I have mine powder coated right along with the other parts, then use a peice of duct tape over the end of the driver so it doesnt mar the powder coat while installing...

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for cutting I use all sorts of tools..but my most used tools would be these 3..hard to beat them when it comes to cutting and fitting(the die grinder also takes all sorts of burrs for metal removal besides the rollock pads and sanding disk...

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Matte Murder

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AKSNOWRIDER that set on the Dragon are just a work of art. You have the rear suspension tied in to it and the tunnel rack is all part of it too. Just so you know NOT "anyone can do this". I was with you on the posterboard part but when you went to scanning and waterjet you lost me. Why did you change the design for your set you made for the pro? The Pro set is much less involved it seems. Also, how do you apply the glue so there aren't thick spots that will hold the parts apart too much and make it uneven? Do those clamps(very cool) just overcome the glue and squeeze it out?
 

AKSNOWRIDER

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AKSNOWRIDER that set on the Dragon are just a work of art. You have the rear suspension tied in to it and the tunnel rack is all part of it too. Just so you know NOT "anyone can do this". I was with you on the posterboard part but when you went to scanning and waterjet you lost me. Why did you change the design for your set you made for the pro? The Pro set is much less involved it seems. Also, how do you apply the glue so there aren't thick spots that will hold the parts apart too much and make it uneven? Do those clamps(very cool) just overcome the glue and squeeze it out?
thanks matt..yes the dragon was some work, I put about 120 hrs into it, its hard to tell in the pics put the boards are raised 1.5 in. at the rear, made the boards shortened the factory rails to fit the new boards, the rear suspension mnts, the rack, sides and hitch...with that said..the pro just doesnt need all that..although I did add the gas rack setup its just lower profile so its not noticable..and the suspension brackets are already aluminum vrs the dragons steel(and very heavy I might add), the boards are much better on the pro..and if I did mod the boards..I would just add (or build) skinz air frame tube boards..as for the glue...it comes in a dual tube dispenser cartridge, you can control how much you are putting on..and it doesnt take much...you dont need to cover the whole panel..just between the rivits top and bottom to keep the metal from spreading and folding under a big load...but I do still think anyone can build these..its pretty simple to do..and I am glad to offer suggestions and ideas to any who need it...now..if the sky was the limit..and I was only building for total light, strong, cool bling affect...I would remove the stock boards/sides completely..build an inner board out of .40 aluminum, then an over lay out of .60 that is fancifully designed with say AKSNOWRIDER across it with a cutout of the sled being ridden cut in as well.. the boards would be all out of high strength aluminum tube made like a airframe board...but thats a bit fancy for an old guy like me to be riding around on..most likely everry young hot shot around would be wanting to race or something...
 
D
Sep 27, 2011
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Ontario Canada
no pain at all , thats why I did the thread so others can see what is possible...I do use glue, either lords adhesive(what polaris uses on the chassis) or 3M panel adhesive(what most car manufacturers use to assemle cars now days)the lords is physically stronger..but the 3M is cheap, readily available, and way stronger then what the aluminum will take..rivit wise I use solid aluminum aircraft rivits(the fancy rivits that hold planes togeather), they are cheap, easy to use and way more durable then pop rivits or screws...plus on the off chance they ever do loosen up..simple re stike them and they tighten right back up..I powdercoat everything..including the rivits..here is a pic of my old dragon..I made running boards on it as well..

Picture328-1.jpg
Nice peice of work.
 

AKSNOWRIDER

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Well got it tore back apart, cleaned up and started the final assembly....first base side going on....
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this is what a solid rivit looks like once it is installed.....
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base is rivited on, notice the cleco's holding the back till the overlay is ready to go on...
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overlay installed and rivited in place...
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hopefully this thread gives some of you some ideas and a good base to take on some of these projects...thanks...

and the finished tunnel...
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diamonddave

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Yeah you lost me at waterjet and cnc and blah blah blah. Don't you owe me RT airfare for some electrical diagnostic wire and sensor chasing and some custom magic transmission work, LOL????
 

AKSNOWRIDER

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Yeah you lost me at waterjet and cnc and blah blah blah. Don't you owe me RT airfare for some electrical diagnostic wire and sensor chasing and some custom magic transmission work, LOL????
lmao..too late that sleds been gone for 2 seasons now..so what are you wanting to do to your dragon?
 
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