04/13/14

RV-6 gets a Moonlite

After diving head first into astrophotography I’ve come to find out that a few of my decisions that were made intending to save money ended up actually costing more in the long run. Case in point, buying my AVX mount without spending an extra $100 on the version that came with a 6″ Newtonian telescope ready to go for hooking a DSLR too.

But I suppose its not a total loss, I’m actually learning quite a bit. So getting back on topic, my amazing old RV-6 optical tube I picked up from a gentleman in Florida was in need of an upgrade. For normal visual use the RV-6 is quite amazing, and the focuser on it even though simple does work quite well. The problems start when you start trying to balance a DSLR on there. With no thumbscrew to hold the eyepieces or camera in place everything wobbles around like crazy, blurring pictures, dropping things on the ground if you forget the tube rotates when its slewing about, etc. Its really just not made for this kind of use and since I really liked the old RV-6 I decided to go ahead and replace the focuser.

After measuring and reading up on what was on the market the only real option was a Moonlite focuser. The Orion, Synta, Feathertouch, etc focusers all seemed to be at minimum 1.6-2 inches tall at minimum height. Moonlite’s are short little things right around 1.5 inches tall which is really important for DSLR’s and prime photography . They also have a reputation that is hard to argue with, a build and finish that match that reputation, and a set of options that will fit just about any configuration you have.

So I won’t go into all the numbers and math I did but I ended up getting a Moonlite that had a 2″ standard drawtube, and a triknob with shaft lock. In hind sight I think a shorter drawtube would have been better, but more on that later.

 

When I ordered the focuser i also got  a 7inch curve adapter which fit the RV-6’s diameter perfect. I tried very hard to not cut a hole that interfered with the original focusers mounting points. This way the Moonlite can be removed and the original focuser bolted back on if needed, it seemed important to make sure any changes made were reversible since RV-6’s are such a classic telescope. Cut the hole with a Dremel and steak knife making sure to protect the mirrors during. Bakelite cuts super easy.

 

Old and new, quite a difference.

 

Going back to that 2″ drawtube, it kind of blocks quite a bit of light. If I were to do it again I would order a 1.5″ drawtube and a bunch of extensions. Still have not decided if I’m going to trim those bolts, and what to paint them black with.

 

So to reach prime focus with my DSLR’s the Moonlite helped a lot, but was not quite enough. I thought about adding longer bolts on the mirror assembly to push it about an inch further up the tube, but then realized that the frame could just be flipped in the tube for an extra inch.

This worked out great! Focus for my Canon was actually now about a half to quarter inch above the top of the focuser now. Right where the picture above shows it.

 

And here it is with my only 1.25″ eyepiece, not bad looking! Only problem is that when flipping the mirror frame to push the prime focus location further out, now the eyepiece is just barely in focus when the drawtube is fully extended.  So now I need to shop around for a one inch drawtube extension to fix that. But, no more wobbly or dropped eyepieces or DSLR’s! Now the old RV-6 can be used for another 50 or more years to come.

 

EDIT:

When I got the telescope it was missing its tube rings and apparently no one sells 7.5 inch tube rings which was a bit of a problem. Its sort of important that you telescope can be mounted on its mount if you plan on getting anywhere. For any RV-6 owners out there that are missing their tube rings, you can use a set of modified Orion 182MM Tube Rings. The rings are not rotatable and the hole on both size of the hinge where you bolt them together is threaded. Also, the OD of the RV-6 tube is around 7.5 inches, the diameter of the Orion rings are 7.16 inches which makes things tight.

Good news is that its super easy to get around this. I ended up drilling out the threads on one half of the rings (the side the wingnuts are on) and then bought a pair of wingnuts and some 2 inch bolts. This way the tube can rotate with no issues. You could also get away with just using a smaller diameter bolt that was longer, and maybe just epoxy the bolt head end so that it cant spin when you adjust the wingnuts.

 

02/10/14

Broken Blinky, Polaris Track Swap

Blinky, my wonderfully horrible looking old 71′ Sears Sportster, decided back in January on one of those -40F days that it would be fun to lock up its track about a mile from home. I hopped on it that night since for the most part its always been very reliable and also in part because its the only one that runs right now with a headlight. So while out scouting down the road to see if I could make it to work or if the drifts had closed the road in yet, it decided to stop moving.  And then I walked home, which was the coldest walk that I had ever experienced.

On the way back I had plenty of time to think. The Sears is pretty much worthless and it came down to finally scrap it and put it out of its misery, or fix it. For some reason I really like it, so scraping it no matter how tempting of a thought at the time was not really in the cards (Also it has a lifetime historic snowmobile trail pass). So what to do with a rusted old ugly sled that I paid $15.00 for, which at that time was already considered scrap metal?

Well, replacing that drive bearing meant taking the track out along with the old drivers. The bearing its self would probably run around 20-50 dollars. Blarg. So the track on that thing is awful as well. Its all dry rotted, cracked and stretched. The track drivers are also not long for this world. So crap I thought. In the end, I wound up at Great Lakes Snowmobile Salvage again, and Paul being awesome as always helped me pick out some newer drivers, a skid, and a new track. So now its just a matter of upgrading Blinkys old outdated drive line to something slightly more reliable and modern.

And the shiny new parts from a 97′ Indy ready to be Frankensteined into Blinky.

Edit: 2-14-14

Wee, more progress.

So anyways here’s whats been removed

Here is the Pile O’ Driveshaft ready to be morphed together

Super scientifical clampification for maximum alignment. I did not measure any of this, it was cold. I placed both shafts on the ground centering the drivers from both so that they lined up/were centered. This showed that the bearing on the right hand side was in the same location, but the newer shaft was about 2-3 inches too short. So, I looked at both shafts, eyeballed and scratched a straight mark on the two by the splines and then cut the suckers up. Then using some 90 degree gussets I had I clamped and aligned them to the edges on the hex shaft so that it formed a nice square channel. After that since the shafts were the same diameter I just butted them up, clamped them down, and started welding.

If you were going to do this properly I would recommend actually measuring things, turning the cut ends down, and then drilling a centering pilot hole on both so you could drop a stud/peg in the center of the shafts and keep them square. Also before putting them together it would be a good idea to get a section of heavy pipe/tube that just slips over the shafts and slide it off to the side. Then after they are welded together, you could grind the welds flush, slide the pipe/tube over the joint, and then weld that over as a sort of coupler to help hold everything together. Or just say heck with it and throw it together like I did, which by the way came out nice and true with no wobble.

Holy cow it fits!

Looks a bit like an old man wearing neon running shoes.

Everything looks good, last major thing is going to be getting 4 new holes drilled for the skid. But getting closer!

 

Edit: 2/15/14

Onwards!

So here is my nasty greasy hand holding one of the skids mount rods. It turned out that the new rods on the new skid where threaded for metric bolts. So instead of trying to locate a set of those I just swapped rods with the old skid that used standard threaded bolts.

I broke down and bought a small chunk of angle iron for the new mounts and then drilled the holes out on them. Also made sure to round off the corners since this is going to be down under the floor boards of the sled and if you ran over your leg or something the sharp hard edge could tear a good size gash. To mount the skid/make the brackets I first drilled two new front holes about 3 inches in front of the existing holes, and then bolted the skid in. The rear then swung up into the tunnel and I just lined the angle iron up with the old mounting tab/hole so that it extended forward to where the rear mounts of the new skid would be.

Better picture of it. Just a junk of angle bolted to the old holes in the back, and then the new holes in the front. Figured this would work good, and just to make sure that it stayed in place I drilled hole through the floor board and bolted the bracket down there as well. There shouldn’t be a lot of pull down force on this, mostly just pushing up into the tunnel, which the bracket should spread the force out fairly good over the area of the floor boards.

The final product! It is about 20 lbs lighter in the rear now and sits quite a bit taller. I have not had a chance to ride it yet to see if the ski pressure/balance is correct on it, but it should be fun. If its out of wack more holes can be drilled.

Also I noticed that the drive sprocket is way out of wack. Its perfectly round, but the center hole is not in the center and there is a lot more flat gear face at the bottom then there is at the top. Must have been machined on a Friday.

So hows it work? Pretty darn good, much better then the cleats. The new track makes the back of the old Sears Sportster quite a bit lighter, and also raised the center of gravity a little bit. Out in the deep snow it gets up and moves much better then it used to with its original skid. While its still not quite floating on top of the powder, its also not burrowing its way under the snow. Also it seems like it has a better time getting its power to the ground where it needs to be. So all in all it was a good mod, one that I will do again when I get around to fixing up the old Fox Trac.

01/30/14

A short story

Michigan, its freaking -14F outside. Windchill makes it near -35F. Getting ready for work, its around 11:00PM on Tuesday.

Truck won’t start. Fires sporadically but its just too cold for it. Heater blend door was set to defrost but for some reason decided to spazz out and is clacking loudly from its home under the glove box. Give up and borrow my folks Tahoe and go to work leaving my truck behind.

Too cold to work on truck when I woke up around 4:00PM, wind still blowing strong. Tahoe is now gone on a trip leaving the only thing I have keys to and that runs my 1954 Buick. Figure screw it, there is no salt on the roads anyways since its too cold for it to do any good, so I jump in it. Its now around 7:00pm at night and about -5F out. Surprisingly Bonnie fires right up and seems rearing to go. Let her warm up for a good 20 minutes before pointing her out into the cold. Heading slowly down the road it becomes apparant that the heater works less then I remember it and I no longer can feel my feet. The defroster is blowing enough to keep the lower half of the windshield clear but the upper portion looks like some form of ice and crystals that you would see in National Geographic.  While heading down the road it breaks through a few drifts with little fan fair, passed a few trucks that seemed very confused to see a 54′ Buick out in this weather.  Get to the store, get something for dinner, and then head back. On the way home I found that the Buick also does not like the cold as it decides to stall in the middle of an intersection. I get out and eventually push it clear and then wait in the dark until the stupid starter switch on the gas pedal resets and decides to crank the starter over. After around 10 minutes it decides to work again and Bonnie makes it back into the safety of the garage. At this point I give up, but my sister takes pity on me and lets me borrow her Jimmy to get to work.

Next morning. Out of work, its -15F out. Decide that enough is enough and decide to work on my truck. Its in the middle of the driveway on an ice patch and behind a 4′ tall snow drift. I climb under it and begin taking the starter off. After 10 minutes cant feel my fingers, retreat to house. Back outside, fight it for another hour taking breaks to stay warm. Give up as the solinoid is no longer even clicking, and its cold. VERY, VERY, COLD. At this point I can not feel my face, back, butt, legs, hands, or feet. Climb in bed and after an hour of watching McHales Navy I finally can feel my back. I did not know that was a thing that could go numb. Hitch a ride into work later that night, pick up a new starter on the way out of work.

Today:

Decide that I will make my truck run as this is getting old fast. Its now 7 degrees out according to the sign at the bank, and winds are whipping stronger then they were a few days ago. It feels the same as it did yesterday, although its supposed to be the warmer. Climb under my truck, start working on it. Trying to get the old starter off again, getting cold, lost feeling in my hands after 10 minutes so I go inside. Back outside, starter almost out, back inside. Again, outside. Old starter is now off, going to put new starter in. Laying under the truck, on the ice, can not feel my back, legs, butt, or feet again and my hands are going numb. Try threading the eyelet of the battery cable onto the solenoid with gloves, not working. Take off gloves, touching anything metal feels like getting burned. I cant support the the starter in one hand while trying to put the cables on, old habits kick in, I put the 13mm wrench in my mouth to hold it to free my other hand.

Wrench hits my tongue and that cold feeling instantly tells my brain what I have just done. I freak out a bit and instantly try to pull it away, while dropping the starter which hits me in the face. I slightly rip the skin off the end of my tongue, which hurts, causing me to close my mouth on the wrench. My mouth is now closed around the wrench and it is firmly frozen to my lips. Great.

Lying on my back staring up at the truck I decide to finish this. Get the stupid positive cable on, and then wrestle the solenoid exciter cable on. I’m really starting to feel the cold now, wind keeps blowing snow into my face from the drift my truck is up against.  Grab on of the big long bolts that hold the starter on, try to line it up while looking directly up at it. Starter wobbles and the bolt falls out of the hole it was started in and hits me square in the eye and proceeds to roll down my coats collar and disappears. Look over and grab the other bolt which actually starts and threads in. My hands are now numb clubs from not having gloves on.

I get out from under the truck, with wrench still frozen in my mouth and attempt to find the bolt that fell down my collar. As soon as I stand I feel it slide around the front of my shirt collar, and then the stupid ice cold bolt runs down the front of my shirt, and into my pants. While the bolt proceeds to freeze the crap out of my crotch, I wrestle around trying to dig through my bibs to get to my pants to recover the bolt. It was very very cold.

Back under the truck, last bolt to go, wrench still in mouth, and my body and hands mostly numb I finally get it started and the new starter is bolted in. The truck starts, finally something has worked. While taking care of tools my hand melts some water and a wrench briefly decides to freeze to it as well. I sigh and continue to get things cleaned up from underneath my truck.

Back inside I finally start to get warm. Jump in shower with wrench still frozen to my mouth, it finally pops loose when the hot water hit it. Hot water instantly seems like a bad idea when it hits my feet, back, and hands. Feels like what I imagine falling into a cactus must feel like as all the frozen nerves start to wake up, and are instantly not happy about it. Pin pricks everywhere. I turn the water on cold and it actually feels warm. Eventually thaw out. Try to eat Cookie Crisp while watching the Today show. Can’t taste them due to the wrench that froze to my tongue.  Realize I never will be as cool as Al Roker. Go to bed.