New World Datsuns...

Well I say you’re doing a fine job of accomplishing all that.

I made a new secondary spider assembly, I used the 3.1" secondary mirror as I was not sure the 3.5" would fit, I did some measuring and the 3.5" might fit, I will worry about that later, I am happy how this one turned out, it is very light, maybe a pound or two, the other one weighed a lot.

I cannot take credit for this design, I went thru a spider thread and copied the over all design, and made improvements as needed for my situation, I am happy how it turned out so far.









You can see the spacer holding the vanes in position in the photo below, I "V" cut the ends to spread the tops of the vanes apart as gravity and the weight of the secondary wants to pull the tops of the vanes towards the middle, it is about the wedge shape of the vanes rather than a "V" shape.



I put a brass spacer here to keep from collapsing the vanes as they are very thin.



The vanes are so thin they are almost invisible when collimating the scope, the other spiders were obvious, this one they are sort of like a out of focus blurry shadow, one had a twist in it, I twisted it a little and it disappeared into the shadow I mentioned, this is something new to me, I learn new things all the time about this hobby, I am hoping the spikes I could see when looking at a bright star are smaller.

I guess I should have put this here instead of my work truck thread, I bought another set of wheels for my new Dob.



I am planning to go to the Jrock shop Datsun meet/get together tomorrow.

Long story, short version, the vanes I made did not hold tension equally, so the top of the vanes warped, made a new version and put an upper ring on it so the spider vanes are musical instruments now, had to basically start over.



The spider vanes are so thin I cannot see them thru the eyepiece, I am hoping that get rid of the diffraction spikes I see on brighter stars.



I make stuff and discard it just as fast for a better version, it will never end.

This is a pretty cool rabbit hole.

This is what I woke up to this morning.





Understand this is unusual but it does not mean the end of the world, when was a kid I remember selling cub scout cookies in a blizzard during baseball season, that was in April also, once you get old you have seen almost everything, almost nothing is new.

I did some stuff I have mentioned before, I moved the wheel axle/counterweight over an inch towards the rear to clear the collimation bolt mit was over, you can see in the 3rd photo I stiffened up the axle holder, before it was just a ring, now it has a brace also.






Here I extended that collimation bolt, I extended it about 4" and put a spacer around the longer bolt, it works the same as before except the knob is higher.







Next I put a Telrad on it near the focuser, a Telrad is like a finder scope, some people use a Telrad, then a right angle finder(RAF) to center it in the low power eyepiece, then they use the low power eyepiece to center it perfectly so they can use a high power eyepiece, the Telrad, RAF, and low power eyepiece compliment each other, but that adds weight on that end of the dob telescope, it does not effect my large dobs too much, but a 10" dob(the most popular dob there is) that is a lot of weight that has to be counter balanced on the fly.



I made another mirror cover as the knobs for collimation messed up what I was using, I made little tabs out of scrap aluminum to hold it there, I will buy 3 knobs to hold it, it is within a 1/4" of touching the primary mirror, I cannot even get the tip of my little finger in there, I hope it keeps dust off the mirror.



I pulled the base apart to try to make it turn easier which it was not that bad, I put a Lazy Susan in and doubled the Teflon pads(stacked 2), but I think the 2 Teflon pads were slightly too high and the base board is not resting on the Lazy Susan, I might try shimming the Lazy Susan with a thin piece of Stainless Steel sheet metal I have, I tried this once before and the Lazy Susan was too high and the scope turned too easy, there is a sweet spot somewhere in there that I have not found yet, I forgot to take photos of that as it takes time to pull the scope apart far enough to get to that part of it, then it takes time to put it back together.

I did some major lightening today.




I can get to the collimation knobs now thru the side.



I also bought 4 knobs, 3 for the mirror cover and one for the axle end, they were $7.50 each, but I got a senior discount so it was $29.something with tax.





The axle knob, this is way better than the wingnut I was using.



I will think about this for a while now before I pull it apart and paint everything where needed with flat black in case i think of something else I need to do, I also am looking for either cloth flat black electrical tape, or felt for drawer bottoms with a sticky back that I can use on the truss tubes to stop light reflections as they are a bright silver aluminum color right now, tomorrow I may go to Staples as they had this online, if not I will go to Grovers Electric and Plumbing looking for the tape, if they have nothing I may buy 3/4" pipe insulation as that worked on my 14.5" Starsplitter until I can find something else, I used shrink tubing on my other 16" dob but that stuff weighed so much I do not want to use it anymore, it likely added over 10lbs to the weight of that dob, the box it came in was really heavy, and I had to use a propane torch to shrink it as my hobby heat gun did not do anything, and it took hours anyway.

What about wrapping them in roofing felt or even felt fabric? Both of which should be flat black. Just trying to throw out ideas you may haven’t thought of.

I went with the cloth tape, less than $20.00 for m4 rolls that covered 2 truss tubes per roll.





I took everything apart and painted the necessary areas flat black, I will likely use Marine Spar Varnish on the unpainted areas.

I painted and sealed everything over the last few days, the only thing left to paint or seal is the UTA(upper tube assembly), the lower and upper rings need the bottom and inside sections painted flat black, and the spiders need everything painted flat black, everything else needs to be sealed with that "man of war spar varnish", to use the flat black spray paint I will need to either pulled the UTA apart, or maybe I can wrap the secondary in plastic and basically paint everything black as I am not sure I can paint 2 sides black without getting overspray on the other 2 sides, the only other choice is to paint everything with a brush.

Here are random photos of the dob, the harder it is to see details of black areas the better that is.

This is the mirror cell area.





Here are the side bearings.





I also put the axle holder inside the base box instead of on the outside, since I have slightly smaller side bearings they are less likely to hit the ground when moving the dob around like my other one does sometimes when topping the top of a ramp and going down again, I did this as clean as I could hoping to have a cleaner look for a frankenstein type box where all the screws are visible, it seems like everyone goes for looks, I go for function and my dobs are likely in the light weight category, there are others in the ultralight weight category, mine do not suffer the issues of the ultralights.











I still need a shroud, I am uncertain what I want to do about that, the person I had make the other shroud is the one that gave me Covid, and I started to wonder if I was going to even get it at all, I cannot sew by hand except for buttons and the sewing machine I have has seized, I suppose I could ask around about the neighbors and see if one of them would like to make some cash, I will think about it some more, I suppose I could go to the clothing supply store and ask about people they might suggest, I would like it to fit tighter than my other dob although that one works without the material sagging into the light path.

I put the dob outside for photos, it is basically done and ready to use, but conditions have not been that good this year so far.







Here it is with the shroud for the other 16", it is a little too long, I asked one of the neighbors wives if she would be interested in making some money making one for me, I shall see if that works out, I am supposed to show her the shroud in the next photo, she has only had her sewing machine for a year.



Tonight was supposed to be a good night, but it is not looking that great so far.

I forgot, I rototilled the garden today, it took a while, this is kinda late for me for my garden, but the recent freeze and snow killed all my neighbors tomato plants and other plants also, I lost nothing.

When I rototill, I make the dirt soft to the point I cannot roll the scope/dob to its observing spot, this year I might install 2" X 8" X16" cement blocks, a row for each wheel to get me to the cement observing spot.

Well I drove 9 hours today, 450 miles each way, it took me around 4.5hrs each way, I used to enjoy driving like this, not so much anymore.

When I got to where I was going the 521 kingcab turbodiesel was acting weird, apparently I ran out of diesel as when I was priming it there was nothing coming in from the tank, I had diesel fuel with me(10 gallons), so I poured 5 in and started pumping the primer again and I got fuel, it started pretty fast considering it ran out of fuel, what is baffling to me is I still showed fuel on the gauge, I stopped at a station and put $40.00 more in it and made it home with spare fuel in the tank, not sure why I got better mileage coming back as I drove fast both ways, I tried to keep it under 3000rpms(85mph) which I did most the trip, I guess I had an east wind and drove uphill on the way there and I was down wind(east wind) and driving mostly down hill on the way home, I drove to Moses Lake WA and back.

Why did I go to that place, I bought an almost new Hubble Optics ultralight UL20, which is a 20 inch mirror ultralight Dobsonian telescope, I paid quite a bit of money for this dob with all the bells and whistles(it has Goto electronics), I likely saved over $3000.00 and a year or more wait buying new, as premium telescopes/mirrors are hard to find these days, there are waiting lists for US made telescopes/mirrors of a year or more, I wanted a 24 inch($10,000 for just the mirror) but this is what I settled for(local), I have no photos right now, I will try to get some tomorrow.

Well here it is without the primary mirror in it, I have been fiddling around with it for the last couple days trying to figure it out and get everything working to the point where I feel it will not break down while using it, I am using the hand controller as I have no idea how to download the Goto onto my laptop let alone if it is the app for this Goto, then I would have to learn how to use that, the hand controller seems like an upgrade to me unless it moves too much when used, but I will deal with that when I have to as it has more than one speed, but I don't know how that works either.



I have made a few modifications, well it is more accurate to say I added a few things that make it tighter, it was kind of sloppy side to side movement which it should not even have, the original owner thought that was a great idea, it was stupid simple, the manufacturer should have done it.

I have not figured out how to move it yet without breaking it down, my telescopes need to be moved easily, otherwise it is a hassle and will not get used very often, it needs to be simple also, I will think of something, just have not thought of anything yet.

Well what I thought of was not simple, but it is no thought needed once done, all I need to do is roll it to the observation spot and adjust one bracket from locked to not locked and it is ready to use, getting there took some brain power, I guess I still have brains.

I made this bracket, it was mostly right the first time, once I had the design I only added one brace with a second bolt involved, so it has two bolts and a tang holding it in position, it also locks the side bearings in place but they still work normally, the tolerances are tight, but so far the altitude function works as designed.

Here is the bracket.



Here is the tang on the bracket.



Here is the painted bracket with the brace and second bolt.



Here is the tang on the back side in position.



Here is the spot where the tang needed to be with the unpainted bracket installed.



Here is the bracket installed with the other bolt, with the axle installed.



Here is the bracket when I designed it, you can see the part that goes over the altitude bearing trapping it, but it does not touch that bearing, so this on both sides takes care of the front.





Here is what I came up with to lock the back, you cam see it goes under the lower bearing trapping it, when the dob it tilted onto the wheels it cannot fall down, it gets raised with the rest of the dob.



And here the bracket is stored so I do not lose it, it is out of the way there.



Here it is on the wheels, you can see the battery box hanging down.



So I modified the battery box and made it smaller, I had to rearrange everything in this area, but it works fine this way, the second photo shows the bungee cords holding the wiring and battery in position.







I just re-did the Telrad/finder mount and painted it, have not mounted it yet so no photo, this can likely be used now to check out the quality of the Hubble Optics sandwich mirror, I hope it is a good one like my 16" sandwich mirror.

I did stuff in my garden today, I improved my observation spot by adding a path to the spot, it was so bouncy before, now it is smooth, after I did the path I rototilled everything again and then spent over an hour pulling weeds, last of all I planted the lettuce plants.





Last night I re-did the Telrad mount so it would not interfere with the shroud, here it is with the should pushed out of the way for the photo.



And here it is with the shroud in position slide past and under the Telrad mount, I did not drill any new holes.



Fact is I did not drill any new holes anywhere in this dob since buying it, everything I did to this dob so far has used existing holes and bolts, that was the reason for the tang, I did change the battery box though, and I am considering a new UTA as the secondary mirror is out in the open where it can easily get dew on it, but is has to be something light if I make a new UTA, I have more thinking to do.

Tomorrow night is when I am going to use this dob for the first time, conditions are supposed to be good.

Keep us posted on the garden. This late cold has me impatient with mine.

I bought all the tomato plants I am going to buy, but I am not ready to put them in the ground yet, I did plant the 2 lettuce plants I bought, for the rest of the season I have started a bunch lettuce plants with seeds, and I will keep starting them till likely August.

The nursery I bought 3 tomato plants today at said the cucumber plants will be in next week or the week after that, the snow/cold weather killed a lot of their starts and the ones that lived they are not happy with, they buy seeds and start all the plants they sell, they have healthy looking plants.

I worked at a house Friday and seen a homemade green house in the next yard over, I have a lot of sheet glass, when I tore my old garage door apart, I saved all the long pieces of wood that were not rotten, they have this groove where the thin square pieces of plywood went, well the sheet glass was the same thickness, so I made 6 frames for 6 pieces of 76" X 34" glass, when put together they were 80" X 38", I put them on the side making 3 walls, the back(north side) is cement blocks where the entrance will be, well once I got it to sections high I decided it was too high so I took that level down which was not easy to remove or install for that matter, my plan is to put a section on the top front at maybe 45 degrees, , then the other two at a shallower angle and have that rest on the cement block wall, I will have to squat to get in with this plan, but it will not stick up higher than the neighbors fence which was the issue for me.





I will take photos of the finished green house when it looks like a green house.