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Posts Made By: Ron Sowers

April 22, 2004 07:54 AM Forum: Equipment Talk

Fan over center, but...

Posted By Ron Sowers

I installed the fan over the mirror center last night. The install wasn't that bad. Took about 2 hours. It seemed to do it's job but the seeing sucked SO BAD that it was hard to tell! It apeared to clear the image up when it was on. I went on for a while, then off for a while etc. Also compared the defocussed star images with it on and off.
Again though, the seeing was so bad that I couldn't really get a good target pattern no matter what.

It's kinda wild looking when you look down the tube and see this fan hanging over the center of the mirror!

I'll test it over the next few nights as seeing and clouds permit. If this doesn't work then the only thing left to try are the side fans!

Just thought I'd post an update!

April 22, 2004 05:48 PM Forum: Equipment Talk

April 23, 2004 11:21 AM Forum: Equipment Talk

See this pic....

Posted By Ron Sowers

It 's from here
And this is what my star images looked like when REALLY REALLY defocused, with or without the fan.

April 24, 2004 11:06 AM Forum: Equipment Talk

My next project along with fans..

Posted By Ron Sowers

Another thing I'm going to try, a bearing between the ground board and the mount. I've tried milk jug washer, wax, oil, ect ect, it's still sticky.
When I'm at higher powers, if I pull the scope towards me, the tube flexes a bit moving the image all the way back across the feild but the scope didn't really move, if I let go it just un-flexes and goes back. So If I pull harder and kinda stutter the tension, it'll finally jerk way past, grrr.

I'm getting well known at the local Lowes now for buying doo-dads. They always ask, 'what is this for', 'umm to hard to explain' haha


April 25, 2004 10:38 AM Forum: Equipment Talk

Side fans....

Posted By Ron Sowers

Well, I got the fans, I tested configurations with a mock up to find the right distance etc. Definately need both fans blowing from the side to cover the whole surface. I just carefully measured where the holes go, now to cut. Yikes!!! I think I have cutotubophobia, I need a therapist haha. Just cut right, it'll be ok... ;-)


ps- Ya know those clip things I had stuck inside the tube to hold the center fan, and we were talking how one might come loose and let the center fan hit the primary? Well, there still in there, I could NOT get them loose and didn't want to pry with a screw driver and mar the inside of the tube. So, those do stick quite well!

April 27, 2004 07:42 AM Forum: Equipment Talk

Hey Mike C.

Posted By Ron Sowers

So have you tried out the dob with the pulling fans yet? I'm wondering how your results were.

I did some more tests last night, the seeing wasn't too hot, I really don't notice a visible difference on the planets with the fans on or off. But the out of focus star image does show less heat blobs with the fans on. Maybe if the seeing was better?

I put a 4 inch fan on the back of our 6 inch EQ newt. It has a plastic mirror mount that the mirror is glued to so I had to make it a pull fan like your set up on your dob. On that scope it seemed to really help. I was able to hit 300 power on Jupiter and it looked pretty decent for a 6 inch F5. Way better than it has in the past on that scope, but nothing to the good veiws in the dob.

Clear skies!

April 29, 2004 04:47 PM Forum: Equipment Talk

Vent covers

Posted By Ron Sowers

Hey folks,

Someone mentioned using speaker grill's for vent covers. I have searched and can only find stuff like this..

These wouldn't block light from getting in. Has anyone seen a round vent or something that would let the air out but have dividers like the air vents in the car ( but don't have to be movable)?


April 30, 2004 03:58 PM Forum: Equipment Talk

Weird questions

Posted By Ron Sowers

1) If a person has bigger eyes, do they gather more light?

2) If there is a planet ruled by insectoids, what do their telescope's eyepeices look like?

3) If light has some properties of particles, when we look at Jupiter, does that mean actual particles FROM Jupiter have been absorbed into our eye?

4) If you took one of your eyes out, left it attached so it was still working, then pointed it at the other eye, what would you see?

These are just weird things I've thought of and as you can tell, I'm too tired to think right today LOL :-D


May 1, 2004 07:28 PM Forum: Equipment Talk

Final fan setup

Posted By Ron Sowers

I decided to make things neater and tidier, and change the rear fan. I'll just use a big house fan for the first stage cooling, then the built in fans to keep things cool and remove the boundary layer. Of course, it clouded up AS I was finishing this up! Dang it, imagine that haha

Here is the bottom fans, wires now go up inside and exit out the rear of the tube..

May 10, 2004 02:53 PM Forum: Equipment Talk

2 weeks evaluation on side fans

Posted By Ron Sowers

For those who are interested, I have been testing the newt side fans over the last 2 weeks and have some definate conclusions on them.

1) Both 3 inch fans, running at full power NEVER cools the mirror fast enough to catch up. That's why I kept thinking the fans were not doing anything.

2) They do remove the boundary layer as evidenced from out of focus star images. BUT, the mirror must still be changing shape from cooling. Pyrex mirrors might not have this problem.

3) If I pre-cool the mirror for 15 minutes with a big house fan, the images will be perfect for a while, but if the temp is still dropping quickly, after 5-10 they start to warble and get fuzzy again. Running the fans at this point delays and slows the degradation but doesn't stop it.

4) Running the big house fan for an hour though makes the images stable enough I don't even need the side fans.

Conclusion- I chopped holes in the tube for noth'en! :-(

anyone else who's recently done this have any input?

Take care!