Monday, July 30, 2012

Short report

Main tube with squeeze out epoxy removed, and with the was paper rolls still inside, weighs 916 grams.
I am guessing the wax paper weighs 20 grams, based on the one I did not use weighing about 7 grams.

The tube sections weigh 566 grams, the sleeve fabric 192 grams. 916 - 566 = 350.
350 - 192 - 20 (wax paper estimate) = 138 epoxy
total epoxy, fabric =330
% resin to total weight = 138 / 330 = 41.82 %

The holy grail ratio is 70 / 30. 55 / 45 was my goal.

 I saturate the cloth with in excess of 100% fabric weight, and  with short bladders got little squeeze out, I am surprised. I got lots of squeeze out, so much that the tube was glued to the bench, despite that it was on 3/16" spacers.

The only explanation for why more epoxy did not get trapped inside the main tube, would be as follows.

The expanded inner tube is pressing the wax paper against the inside wall. Sealing the ends of the wet fabric roll, the only place it can go is out the joints which it did in spades.  This was not expected.

And I am happy it worked out this way.

I'm pretty sure I can get most of the wax paper out with water / alcohol mix, and a 2" OD wire tube brush.

Sunday, July 29, 2012

Main Tube Bonding

Main Tube Bonding
Edited, and compressed. Time was approximately 45 minutes from start to finish.

This does not include set up, and fabric cutting. Clock started with epoxy being mixed.

Did not go as well as hoped, but well enough. I could roll the fabric a little tighter. Lots of refinement possible.

Pressure low 20 psi for 5 minutes, then increased to 85 psi. I did not max it out.

Neat sample leftover was hard gelled about 2 hours after mixing. It was close to 90 in the shop today.

Tube preperation

Tube prep

Its easier to do this prior to mitering.

Flex hones come in a wide range of sizes, and grits.With CF use water as a lubricant.

This is an important step.

Saturday, July 28, 2012

Wax Paper

video link is here:
http://youtu.be/NK6z1TvnU1Q

Wrapping  a mandrel, then getting the fabric  tube onto the inner tube is not so easy.

Gave up and was washing up, paper towel holder was empty. Bingo.

Wrap the fabric around the tube, slide the tube onto the inner tube at the joints, remove if possible, but why worry if not. It can get gone later on.

Tuesday, July 17, 2012

BURB has moved here

Anything new will be here.

This is easier for me. It is a time issue.

Comments are on, but chances are I will not reply.

New stuff will be added, "when I get around to it." 

If you are interested, check back now and then.