The continuing saga of Niksons 1402 IMP sn 129

Hi. I'm the guy that bought Niksons Imp. I will be continuing to make improvements to customize it for our use as a cabin access vehicle. So far I've added mirrors, removed the mechanical fuel pump and replaced it with electric, made a snorkel with a K&N filter and vented the crankcase to the engine intake. I added low mounted LED fog lights as we get a lot of winter fog in the Ellensburg Wa. area. I moved the battery from the passenger forward floor area to under the passenger seat along with the winch relay for more leg room on the passenger side. I removed the dash and will build a smaller one for more leg room on the drivers side. To overcome the noisy cabin, I installed a Sigtronics aircraft intercom and 2 Astrocom headsets (ebay) For rear passengers I installed 2 Honda civic seats and added seatbelts to all seats.

I removed both tracks as they were running very tight, even with the idler set at the minimum setting. One track had 53 grousers and the other 54. The track with 53 grousers (213 1/2") was in pretty bad shape but the other looked okay but was also tight (214 1/4"). I don't think Nik had a chance to rebuild them as he wanted to use the cat last winter. From what I can gather from the parts manual for the 1402, there should be 55 grousers with 4" pitch. That would make the belts 220". I have belting and will make a 220" track and see if it fits. I can always cut it back to 54 grousers and 216". From my calculatons of 1/2 the circumference of the sprocket and idler at the inside of the grousers (belt diameter) plus 2x the center distance of the idler and sprocket, the theoretical circumference should be 218 with the idler fully back, 220 at the center positon, and 222 with the idler fully forward. That fits the 55 grouser model at 4" pitch.

I could be completely wrong on this, so if anyone has first hand experience, I would appreciate any advice. It will be a few weeks till I commit to cutting and drilling the belts.

I'll have more as work progresses.

You have the same drop-center grousers that I have on my 1404 and I've got 54 grousers/track (both sides). I think the 55 number applies to Imps with straight grousers, but that's an assumption on my part.

Ron

You could be right. I did see a 1404 with straight grousers that had 55. With straight grousers the pitch distance would stay constant as they go around the sprocket and idler, but drop center grouser pitch will increase as it goes around because the radius is bigger than the belt. Maybe I'm overthinking this. Is the pitch of the straight grousers the same as drop center when the track is laid out straight?
The 1402 parts manual I have shows a drop center grouser and that there are 55.
My plan was to make a track with 55 grousers at 4" centers and if it is too long I can always shorten it by one.

I made one grouser already so I would have 54 per side. If the 55 grouser track works out I can make 2 more.

Turbinator wellcame to the party

From Nikson to Turbinator..... So
It reminds me sometimes when i had already finished my paintings, and i turn them over, so i did not need to see what i have done on those paintings, for several days, and i start something else in my workshop.
When i turned over in two weeks i realize that my pictures are not finished and i have to do some other changes (Shapes - colors etc)
Sometimes we think that the parts of a story just over,- happy end etc, but in the next minutes, from that story, something else has just began.
Who says the opposite. This scaffolding procedure to improve an already reconstractive project, is a another level for us to think, that nothing is Over.

Regards Nikos

Thanks. I do the same thing. After I build something, I'll go back months or years later and wonder "Why did I do it that way?"

I'll be at the cabin with no internet so I won't have any posts for a few days.

Congrats on an awesome rig and welcome to the zoo!

Now, what does the elevator(?) on your workbench go to?

The reason the snowcat is outside the hangar is that in my other life I am designing and building an 80% scale T6A Texan ll Air Force trainer. I was just ready to start riveting the horizontal stabilizer when I bought the cat.
I have the tail pretty much done, engine and prop are done as well as the landing gear, instrument panel, avionics and canopy. After riveting the stabilizer I'll start on the wings.
But that's a story for a whole different forum.

nikos said:

Turbinator wellcame to the party

From Nikson to Turbinator..... So
It reminds me sometimes when i had already finished my paintings, and i turn them over, so i did not need to see what i have done on those paintings, for several days, and i start something else in my workshop.
When i turned over in two weeks i realize that my pictures are not finished and i have to do some other changes (Shapes - colors etc)
Sometimes we think that the parts of a story just over,- happy end etc, but in the next minutes, from that story, something else has just began.
Who says the opposite. This scaffolding procedure to improve an already reconstractive project, is a another level for us to think, that nothing is Over.

Regards Nikos

Click to expand...

I hope now you guys see why I let my "creation" go to this guy...

I was pretty sure it was going into the right hands, one way or the other...

Nikson said:

I hope now you guys see why I let my "creation" go to this guy...

I was pretty sure it was going into the right hands, one way or the other...

Click to expand...

No kidding.

And that rocks . . .

what kind of engine is that looks like some kind of turbine I would love tto have one in my snow trac I could run circles around Big Als krusty with one of those. on the other hand they never move under their own power so I suppose you could walk circles around his krustys.

T-prop with an APU background? Custom made or specialty item?

Way cool though . . .

custom made that's got my name all over it any thing to out run the krusty crowd. to be serious though that is one nice power plant hope he has a lot of fun with it.

Nikson said:

I hope now you guys see why I let my "creation" go to this guy...

I was pretty sure it was going into the right hands, one way or the other...

Click to expand...

Nikson......... 10 points

The engine is a Sundstrand T62T2A1 with a -32 power section. The core engine is the APU from a Chinook helicopter which was 95 hp. I upgraded it with the turbine wheel, diffuser, nozzle, and burner can from a T62-32 engine of 150 hp. The accessory drive, starter, alternator, fuel control mods, prop gearbox and prop are my own designs, manufactured in my hangar. I built about 45 of them over a period of 10 years, the last one in 2001. The supply of good cores dried up although you still see one on ebay now and then. I am finally getting around to building an airplane around the one I have left.
The 10 gallon tank in the 1402 would keep this engine running for about a half hour, but it only weighs about 100 pounds so is well suited to a light aircraft.

also suited to a light snow trac but I suppose one would have to have a large fuel tank to get any distance

Not to mention that Jet fuel is over 5 bucks a gallon.

5? lucky you Heating oil #1 is 6.50 a gallon up here add the airport tax and delivery charge I bet you would be getting around 8 plus here if you had to run aircraft spec jet-a.

I got some more work done since the last post. This week I got the new dash made, and added some more carpeting to the interior. Put in a little tray so my wife has a place for her cell phone etc.

There was nothing wrong with the dash that Nik made, but I needed some more leg room so I condensed it down with smaller switches etc. I also added a fuel gage, ammeter and idiot lights. By putting the fuse panel under the dash, and concentrating the wiring on the drivers side, I was able to eliminate a lot of extra wire.

I pulled the pan off the engine and added a boss for an oil temperature probe and a new drain boss so the oil comes out straight down instead of sideways. (After getting oil down my arm and all over the place while draining it. I was not a happy camper )

It is supposed to rain tomorrow so I am going to bite the bullet and start on the tracks. I have all of parts and materials now to finish them so I have run out of excuses. I'll post that process as it progresses.

That dash panel came it looking really good, hope to see in the woods sometime.


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Wow. Very nice.

how did you do the lettering for your switches that looks good

I use AerogGraphics in Loveland Colorado. www.aerographics.com Ph 1-800-336-9633. They specialize in aircraft graphics but can do anything you want. Call them and they will send you a catalog.

did you buy the lettering from them or did you have to send out the panel if I could get the lettering I'm interested if the panel has to go well I will have to do something else.

Just tell them what you want, and they will mail them to you. They are self adhesive and easy to apply. I had mine in a couple of days.

Awesome Job!

I second the lettering comment. Where can I get that for my dash next year?

Aerographics in Loveland Colorado. www.aerographics.com They are self adhesive and easy to apply.

Before I rebuilt the tracks I had to make 3 new grousers since this cat had 53 on one side and 54 on the other. The parts list for the 1402 shows that there are 55.

The originals are made from 3/4" X .095 square tubing. I couldn't get .095 so I had to use .120. I used the old blacksmith heat and beat technique with a stock grouser as a pattern.

All of the grouser clamps were also pretty chewed up so I made new ones from .187 X 1" 6061 T651 flat aluminum bar. There are 220 of them. After cutting to length and drilling, I ran a bevel mill down the sides of all of them to conform to the inner radius of the belt as it goes around the sprocket and idler.

In the next post I will go over how I calculated the belt length and rebuilt the tracks