PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Hi Mike, in reality...I screwed up and forgot to account for the thickness of the Flow material, peel ply, and 2 layers of CF...that likely added about 0.0800 - 0.100" to the diameter... 
And yes, it would be quicker to redo this than to rebuild the Secondary Mold...after trying to grind out the center....
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
The Secondary Baffle was slit lenght wise along the 3.4 inch direction and then we placed 2 wedges under the 2 layer CF composite to gently pry the Nylon bagging material that I held onto the mold surface with 3M adhesive 
Which as it turned out, was likely the wrong approach to take...but we will better know tomorrow when we infuse the much larger Primary Baffle assembly.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Weighing the Secondary Baffle we find that the bare cloth weighed 27 grams, but that was including material that was beyond the cut line and not used. The finished length of infused carbon fiber was 4.8 inches and we cut that down to 3.4 inches in length...
Final weight 31 grams...and again, likely at about a 30-40% resin content per carbon weight... 
Very light, stiff, and a beautiful mat finish that has NO reflection a low grazing angles...just what Mike ordered 
Thank You Mike
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Finally, the BIG Primary Baffle
This time NO 3M spray adhesive to hold the Nylon bagging material to the molds surface...just tape at the ends, hopefully it will slip off after cutting the ends square and to length.
Here is the second layer of Carbon Fiber layed up dry in the stack that started with bagging material, then screen flow material, nylon peel ply so nothing sticks to the inside of the baffle, and now the 2 layers of carbon fiber.
You can see just how shiny the bare carbon fiber is next to the infused baffle.
Tomorrow we will put in the Resin Inlet and Vacuum outlet, bag her up, modify the heating area, and infuse...hopefully with no further episodes
Would have had it infused today, but Visa called at noon from the Fraud Department...short story, everything's OK after 3 hours on the phone...$5000+ and the UPS made a delivery...all of what I did not order, was delivered unsigned for on the front porch!!!
So glad I answered the door and brought the laptops inside to call the police...
Never a boring minute...sorry for the off topic bit, but be careful out there.
Best Regards,
Preston
--------------------
A few I enjoy,
and a few more in the works ;<)
|
Mike I. Jones
Pooh-Bah
Reged: 07/02/06
Posts: 1102
Loc: Fort Worth TX
|
|
So, you can use the CF secondary baffle even after slitting it down the side? Can you bond it back together along the cut line? Or are you going to make a new one after finishing the primary baffle?
Yes - they look nice and black, even without your AeroGlaze black paint on them.
YARG what a mess on your Visa card. Glad you have ID protection and an attentive fraud dept. I do the same thing on all my cards, and it has protected me well. If people would just spend their energy productively on things like making telescopes or guitar pickin' rather than on how to steal from and hurt other people....
Mike
--------------------
56 mirrors, lenses, 16" f/6 Newt, 6" f/10 refractor, TOA-130S, Tinsley 5" f/15 Mak, 6" f/4 RFT, Coronado PST. Still to build: 24" f/10 Modified Dall-Kirkham, 10" f/26 Mak, 8" f/12 apo, spectrohelioscope, Herrig, Schupmann, and a new design you'll like.
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Hi Mike, I'll remove a little bit more so that the OD is correct per your numbers and bond it on the outside...I'll be having to bond some attachments in CF to be able to adjust it anyway...
If I were to make a new one, the OD would be about 0.100" too big...as I forgot to take the thickness of all the layers into account when we turned the taper...If I make a series out of the scope, then I'll remachine the correct tapers on both molds.
The Primary Baffle Mold is even longer and by shifting everything to the small end I believe we will hit the correct diameter without having to return the mold.
I'm staying out of trouble as I have no extra time while building this thing
Take Care,
Preston
--------------------
A few I enjoy,
and a few more in the works ;<)
|
BluewaterObserva
Post Laureate
Reged: 05/18/04
Posts: 4763
Loc: Zuni Mtns, NM
|
|
What a project to be involved with.
Just getting a .8 meter newt up and running under a 6 meter dome has proved to be the most I think I could ever strive for.
Great thread for sure. I sit here in awe after reading much of the thread.
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Thanks Bluewater, more to come shortly I hope...all of this morning with the Fraud Team tracking down details...
Regards,
Preston
--------------------
A few I enjoy,
and a few more in the works ;<)
|
Mike I. Jones
Pooh-Bah
Reged: 07/02/06
Posts: 1102
Loc: Fort Worth TX
|
|
Just had to put up another rendering of the finished scope, this time with the 2-element field flattener/corrector, FLI focuser, FLI filter wheel and SBIG camera. The only thing I don't have in the ZEMAX file right now is the primary mirror conical taper and flat back diameter.
Mike
--------------------
56 mirrors, lenses, 16" f/6 Newt, 6" f/10 refractor, TOA-130S, Tinsley 5" f/15 Mak, 6" f/4 RFT, Coronado PST. Still to build: 24" f/10 Modified Dall-Kirkham, 10" f/26 Mak, 8" f/12 apo, spectrohelioscope, Herrig, Schupmann, and a new design you'll like.
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Looks Great Mike, I think we are starting to recieve photons 
If you need any refinements of the dimensions, just holler.
Way cool diagram 
Regards,
Preston
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Today we infuse the Primary Baffle.
This will be the last time I take everyone through most of the steps in detail...
First we test for vacuum leaks without heat and then for 10 minutes with heat at 160 deg F.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Once it passes the vacuum and heat test for a final 10 minutes, we mixed up 300 gms of resin and 72 grams of cure on the scale.
Here's the infusion after 10 seconds...and we will show it in 10 second intervals until almost the end...Thanks to Jerry Dulatre for his help in taking the pictures...as I sure had my hands full.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
20 seconds
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
30 seconds
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
40 seconds
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
and finally 50 seconds.
As you can see, this all happens very quickly...so everything had better be right the first time...
The time to get to the point of infusion in preparation of the mold, layers, manifolds, bagging and taping, and finally testing was about 3 hours.
The infusion was complete in just over 60 seconds, but we leave the vacuum and heat at 160-170 deg F for about 75 minutes.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Out of curing oven after resting with the heat and vacuum off for another hour. Mold surface temp is still 130 deg F.
We will start to remove the layers down to the finished carbon fiber Primary Baffle.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Peeling back the bagging material to get to the flow material and manifolds.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
Knocking off the spiral tubing that was reinforced with a winding of support wire to help prevent it from collapsing under the heat and vacuum of 26 inchs.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
PrestonE
scholastic sledgehammer
Reged: 04/29/05
Posts: 817
Loc: Houston,Texas
|
|
After both the inlet and vacuum manifold have been removed, it's time to peal off the screen flow material. This has a thicker cross section to help the resin flow along the surface and then down into the carbon fibers.
--------------------
A few I enjoy,
and a few more in the works ;<)
|
Previous
Index
Next
Threaded
[Re: 
Edit
Reply
Quote
