Intro: Traditional Cross Country Ski Groomer
This is a steel cross-country ski groomer for setting a track for traditional x-country skiing (i.e. not skate skiing) designed to be pulled behind my tracked XUV. It could also be pulled behind a snowmobile, although it weighs about 350 lbs, so you'd have to use a large, powerful snowmobile. To make the groomer you will need a welder ( I have a small Miller MIG unit) and basic welding skills. You will also need a drill press to drill holes to attach the various components, and some sort of metal cutting tool(s) (a metal chop saw, band saw, oxyacetylene torch, or a sawzall with a metal cutting blade.) The groomer basically consists of a rectangular 1 1/2 inch square tubular frame with an 4 foot long hitch extension in the front and a 1 ft high arch half way back that allows for raising and lowering of a snow conditioning bar. Within the rectangular frame, at the front, is a hinged snow gathering bar, behind the snow gathering bar is a hinged conditioning bar, and at the back end is an angled snow compactor. Hinged off the back center of the rectangular frame is a track-setter that cuts two grooves in the snow for your skis. The rear 33 in of the rectangle is angled down at 20 degrees with respect to the front 54 in to provide snow compaction. The track setter can float through depressions in the trail because it has two 100 pound gas shock absorbers to provide down pressure. At the back of the rectangle on either side are two "wings" that are used just on downhills/uphills to widen the trails for herring boning and/or snowplowing (the tracksetter is raised when grooming hills so they are groomed flat). The wings have posts that accept optional wheels for transporting it on dry land (for summer storage). The snow gatherer height is set manually using a chain. The conditioning bar, the track setter and the wings/wheels are operated remotely from the XUV cockpit using 12V powered linear actuators. Total cost of the project was about $800, $300 of which was the cost of high density polyurethane for the snow compactor, snow gathering vanes and the skis and base on the track setter, $200 for steel at a used steel yard, $300 for the heavy duty 650 lb linear actuators from Northern Tool, fuse panel, control box, wire, nuts, bolts, self tapping screws and paint. The high density polyurethane is what touches the snow. It is expensive but slippery and exceptionally durable. If cost is an issue you could forgo the polyurethane and use alternative plastic sheeting, like kids sled material, or just wax the painted steel.
1/8 in 1 1/2 inch square tubing - 55 ft (frame, hitch, arch, conditioning bar, snow gathering bar and tracker)
48in x 3/8in U channel (conditioning bar)
1/4in by 1in bar - 12ft (conditioning bar teeth)
1 1/4 in pipe- 5 ft (snow gathering bar and wing hinges)
1in rod - 2 ft (wing hinges)
3/8in plate 6 in X 12in - 2 pcs (wings)
9/16 in rod - 12 inches (wheel mounts on wings)
1/4 in x 1 1/2 in bar - 9 ft (hinge points and gas shock system for tracker)
24in x 60in 14 gauge steel sheet (snow compactor backing)
20in x 25in 1/4in steel plate (tracker)
1/4in x 2 in bar - 4 ft. (front lip of tracker, snow breakers in front of skis on tracker)
1 1/2 inch 1/8in thick angle iron (snow gatherer vane mounts, anti-slip sides on tracker)
4 - 6 inch round 1/4in steel plate (reinforcing gussets and tracking guides)
High Density Polyurethane
1/4in thick 18in x 60in sheet (snow compactor)
1/4in thick 24in x 24in sheet (tracker base)
1 1/2in thick x 5in bar - 3 ft (skis for tracker)
1/2in thick x 6in sheet - 5ft (snow gathering vanes)
6 in long 1 1/2 in U-channel (attachment point for track setter hinge arm)
Hardware and Miscellaneous
miscellaneous 1/2in and 3/8in bolts, nuts and washers
# 30 1/4in self tapping screws and 1 1/4 in fender washers to attach polyurethane sheet to frame and tracker
50 ft 12 gauge red wire
50 ft 12 gauge black wire
4in square aluminum junction box and face plate (control box)
3pc - reversing toggle switches (control box)
3 circuit automotive or marine 12v fuse panel with 10 amp spade fuses (control box)
30 ft. flexible plastic conduit and zip ties (wire guard)
1 pc - heavy duty 650 lb 11 1/2 in linear actuator to raise and lower tracker
1 pc - heavy duty 650 lb 8in linear actuator to raise and lower conditioning bar
2 pc - light duty 200 lb 10in linear actuator to raise and lower wings/wheels
2 pc - 8in wheels with 9/16 in axle - can temporarily attach for dry land transport/summer storage
2 zerk fittings to lubricate wing hinges
5/8in hitch pin
1 gallon antirust paint
Step 1: Step 1 the Frame and Hitch
The frame is constructed of 1/8 in thick 1 1/4 inch square tubing. Overall the rectangular frame measures 60 in wide by 87 in long. There is a 20 degree angle (reinforced with gussets on both sides) located 54 inches from the leading edge which means the last 33 in angles downward. The 20 degree angle compacts the snow prior to the tracker setting the track. Three cross pieces 57 in long are welded at the front, the rear and 18 in from the rear. There is a 24 in X 60 in piece of 14 gauge steel tack welded to the rear of the frame. This adds weight to the back to better compact the snow and serves as a backing for an 18 in X 60 in polyurethane 1/4 in sheet to allow the compactor to slide easily over the snow. The poly is attached to the underside of the frame with 1/4 in self tapping screws and 1 1/4 in fender washers spaced 6 in apart. Vertical tabs with 1/2 in holes are welded in the middle of the back frame and the cross bar 18 in from the back. The tracker and track hold-down assembly will attach to these tabs. The hitch is made of two 40 inch long pieces of 1 1/2 inch square tubing with a simple 1/4 steel pin hitch. I started with a single piece but added a second after I hit a tree and bent the single hitch arm. There is a 12 in high arch located 41 1/2 inches from the front. The arch has tabs to attach one of the linear actuators to lift the conditioning bar. The arch attachment is reinforced with a semicircular gusset.
Step 2: Step 2: the Conditioning Bar
The conditioning bar is useful for 3 things. In new deep snow it removes air from the snow making the track more durable and evens out the snow that has been pushed to the center by the snow gathering bar in front. In hard packed or icy conditions, it tears up the packed snow and allows the new track to be re-set in softer snow.
It is a simple U-shape with multiple teeth extending down from the base of the U. The sides of the U are 1 1/2 inch square tubing 43 1/2 in long with a 1/2 hole drilled an inch from the leading ends for attachment to holes drilled through the side of the frame. The base of the U is a heavy piece of 3/8 inch X 3 in channel 56 in long. The 24 teeth are 1/4 in X 1 in X 6 in. They are welded 2 3/8 inches apart flush with the top of the U channel with 3 inches extending below. The center two teeth are 8 inches long with 2 inches extending above the U channel with a 3/8 in hole drilled to attach the linear actuator for raising an lowering the conditioning bar. I used an 8 in 650 lb linear actuator from Northern Tool.
Step 3: Step 3: the Snow Gathering Bar
The snow gathering bar has 6 polyurethane vanes attached to a piece of 1 1/4 pipe that pushes snow from the sides towards the middle of the groomer. This provides more snow in the center for the tracker to lay track. The height of the bar is set by a chain that restricts how far down the vanes can move but allows the vanes to ride up over bumps in the trail.
To make the snow gathering bar cut a piece of 1 1/4 inch pipe to 51 in. Weld 6 pieces of 1 1/2 in angle iron 12 in long to the pipe at 45 degrees. The angle iron meets and is welded in the center line and a 1/4 in hole is drilled there to attach the chain. The ends of the angle iron should be cut off even with the end of the pipe so the assembly fits inside the conditioner bar. The vanes themselves are made from 1/2 in polyurethane and bolted to the angle iron with three 1/4 in bolts. I cut 6 inch by 12 inch rectangles for the outer two vanes. The inner two vanes are 6 in X 6 in. which leaves 1 foot of space in the very center for the snow to accumulate. A 4 ft piece of light chain attached to the middle vanes slides into a slot on the top of the arch to set the height of the vanes. The pipe with the vanes is welded to two 19 1/2 in pieces of 1 1/2 in square tubing which attach to tabs welded on the inside of the front of the frame with 1/2 in bolts. The outer tabs are located 10 in from the inside of the side frame.
Step 4: Step 4: the Track Setter Assembly
The track setter is made from a heavy piece of 1/4 in plate steel (24 in by 20 in) with 2 skis on the undersurface to set the ski track. It hinges up and down off the back of the groomer frame and can be raised and lowered with a heavy duty 12V linear actuator. The track setter is raised when grooming the downhills or early in the season before there is not enough snow to set a track. At the front of the track setter plate is a welded 2 in lip that angles upward at 45 degrees so the tracker won't dig into the snow. On the undersurface, just in front of the skis, is bolted a welded cutter assembly that cuts a groove in the snow and protects the skis against damage should you hit a log or some other obstruction. Initially I used 1/8 steel, hit a hidden submerged log, bent them up, and remade them with 1/4 in steel. I used a 1/4 in sheet of polyurethane between the steel plate and the skis so it would slide easier. The skis were also made from polyurethane, although it is hard to cut this stuff (it melts rather than cuts on a table saw) and they could be made from other easier to cut plastics or even hardwood. See the diagram attached for the size and spacing of the skis. The skis should be 1 3/4 inches thick and 16 in long, 5 in wide at their base tapering to 2 3/4 in (7 cm) at the depth of the slot. The skis should be set 9 1/4 in (23 cm) apart when measured center to center. I countersunk 1/4 inch holes and attached the skis to the tracker plate with 1/4 in carriage bolts. The tracker has 2 in angle iron along the sides of the plate so when it is all the way down it will not slide sideways on sidehills. I made my tracker 20 inches wide. If I had to do it again I'd probably go wider - 24-26 in. so there would be more room between the side of the plate and the outside of the skis.
The tracker hinges on tabs with 1/2 holes welded in the middle of the rear frame. It is important to get the angle correct so that the tracker sits flat on the snow when in the down position. To get the angle correct I welded a 6 inch piece of 1 1/2 in U-channel down the center of the tracker plate. I then cut a 14 in piece of 1 1/2 inch square tubing, drilled a 1/2 in hole 1 in from the front end and bolted the tubing through the tracker hinge tabs. With the groomer frame sitting on a flat surface, the hitch arm supported at the height of the XUV hitch, and the tracker plate sitting flat on the floor I then slid the tracker plate forward so the square tubing angled down into the U channel. Once I was satisfied that everything was aligned I welded the square tubing inside the U-channel giving me the proper angle. I then welded 2 tabs with 3/8 in holes on the square tubing at the front of the tracker plate for attaching the linear actuator to raise and lower the tracker.
The tracker is held down on the snow by the combined action of the linear actuator and two 100 lb gas cylinders (the type used to hold car hoods up). When the linear actuator is extended and the tracker is in the down position should the groomer drop into a depression the tracker will compress the gas cylinders to allow the tracker to float up and remain in contact with snow without bending or breaking anything. The gas cylinders I bought were 19 in long. At the front they attach to an extension welded off the back center of the arch and at the rear to two 16 in long 1/4 in by 2 in steel struts that hinge on the cross piece 18 in from the rear of the frame. (see pictures) The linear actuator attaches to holes in the top of the struts just behind the holes for the gas cylinders. I used an 11 1/2 in 650 lb actuator I got from Northern Tool. You need to get your actuator and gas cylinders and vertical struts all in place with the tracker set flat to determine the length of the extension back from the arch. In my case it was 12 inches. It might be different for you depending on how everything lines up.
Step 5: Step 5: the Wings, Wheels and Skegs
The wings are 6 in X 12 in 3/8 in steel plates at the rear corners of the groomer, raised and lowered using light duty 200 lb linear actuators. The wings are used when grooming up or down hills to flatten the snow out to a 7 ft width to allow for herring boning uphill or snowplowing downhill. they also have a 9/16 in axel/post for mounting a removable wheels so that the groomer can be towed on dry land for summer storage of the grooming machine. Just in front of the wings are 6 in circular 1/4 in steel skegs bolted through the frame with 3/8 in bolts. The skegs extend down into the snow about 2 1/2 inches. The skegs prevent the groomer from sliding sideways on sidehills and also lift the groomer and the track setter off the ground when crossing roads, to prevent damage to the track setter or the polyurethane sheet under the snow compactor at the rear of the groomer. I bolted them tight to the frame as they don't need to turn to be effective.
The wing hinges are made from 1 in rod that slides up into a 3 inch piece of 1 1/4 in pipe welded to the rear frame. I welded a collar above the pipe holding the wings in place. I tapped a couple of Zerk fittings into the piece of pipe and pumped a bit of grease in to make sure they don't rust together as you don't actually use the wings much.
Step 6: Step 6: Wiring, Control Box and Paint
There are three 12V circuits to raise and lower the linear actuators - one for the track setter, one for the conditioning bar and two, wired in parallel, for the wings. I ran the 12 guage wire through plastic conduit up to the control box. The control box was made from a 4 inch square aluminum outdoor junction box with a sealed cover. In the cover I drilled three holes for reversing toggle switches. On the back of the box I attached a marine 3 circuit 10 amp fusebox with self tapping screws. I zip tied the plastic conduit to the groomer frame and left enough slack at the front to reach the cockpit of the XUV. I used a detachable electric winch power cable to attach the control box to the battery of the XUV. When detached the cable has cable guards that go on the ends of the cable to protect the contacts.
I painted the whole thing with a couple of coats of bright red antirust paint.
I have been very happy with the performance of the groomer. It takes a little getting used to setting the conditioning bar correctly - generally you want it deep enough that snow just covers the entire front of the bar. The only problems have been when I've hit things that I should have missed - I spoke about bending the hitch arm and the ski guards/cutters from hitting trees and submerged logs. So clean your trails of debris before the snow falls. One, grooming tip - the groomer is quite long, so you need to take the XUV to the far outside of any curves to avoid hitting things on the inside of the curve. Enjoy!