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foamy
07-13-2011, 09:18 AM
I repaired my Centurion and find that I misaligned my replacement tube. It has about a 1/16" bow to it, right in the middle at the joint. I didn't check the alignment with a straight edge when I did it. It took the missus to notice and point it out to me. I'm disappointed.

Is there a fix for this without starting over? Is it a real problem? I guess I can answer the last question because I know it's there and it bugs me.

jeffyjeep
07-13-2011, 09:47 AM
What adhesive did you use on the joint?

foamy
07-13-2011, 10:22 AM
What adhesive did you use on the joint?

Elmers Glue-All, the regular white glue.

tbzep
07-13-2011, 10:29 AM
Heat will soften white glue. I've heard that vinegar will soften it also. Maybe a combination of wicking in some vinegar and then heating???

If you don't mind the Centurion being a little shorter, just cut the coupler out and put in another.

jeffyjeep
07-13-2011, 10:55 AM
Right. If you can't get the glue to release and you don't want the rocket shorter, cut the tube just above and just below the coupler, measure how much you cut out, then splice in a length of BT with a coupler at the top and one at the bottom. It will increase the weight a BCH, but the gain in strength and rigidity might be worth it.

foamy
07-13-2011, 11:17 AM
Thanks gentlemen. I appreciate the advice. I'll try a hair dryer on it and perhaps the vinegar/heat combo if that doesn't work. Otherwise, its slice and dice again.

I thought I had done a good job of cutting the tube on this rocket, but it could have been better. Is there a tried and true technique for tube cutting that guarantees or at least improves my chances of a level, consistent cut? I have no special tools other than an Exacto knife and a Dremel.

tbzep
07-13-2011, 11:31 AM
Thanks gentlemen. I appreciate the advice. I'll try a hair dryer on it and perhaps the vinegar/heat combo if that doesn't work. Otherwise, its slice and dice again.

I thought I had done a good job of cutting the tube on this rocket, but it could have been better. Is there a tried and true technique for tube cutting that guarantees or at least improves my chances of a level, consistent cut? I have no special tools other than an Exacto knife and a Dremel.

There are tools you can use to make accurate cuts, but I get great results with a plain old Xacto knife. I wrap the tube with paper to mark my line, then take my time with the Xacto. Very light cuts, making multiple passes. Occasionally I need to hit it with a sanding block after the cut, but most of the time it's good to go.

You can make a razor blade tube cutter from plans that are available somewhere around here on the web. Estes has some tube cutting guides that should be out by now. Product link (http://www.rocketshoppe.com/forums/showpost.php?p=114337&postcount=7)

foamy
07-13-2011, 11:53 AM
Thanks tbzep. I used a variation of your technique last time, but I'll follow your suggestion and use a bit more patience this time round—if it comes to that.

After a Google search, I found the instructions for making a cutting jig and I may build one in the future if I don't master this.

Again, to all, I appreciate the help and thank you.

gpoehlein
07-13-2011, 12:12 PM
I have also heard of using the heat from a 100 watt light bulb to soften white glue (usually to straighten fins, but it might work here as well. An iron might also do the job as well, but I think I'd draw the line short of using the kitchen stove or a propane torch! :p

76gunner
07-13-2011, 01:09 PM
Thanks gentlemen. I appreciate the advice. I'll try a hair dryer on it and perhaps the vinegar/heat combo if that doesn't work. Otherwise, its slice and dice again.

I thought I had done a good job of cutting the tube on this rocket, but it could have been better. Is there a tried and true technique for tube cutting that guarantees or at least improves my chances of a level, consistent cut? I have no special tools other than an Exacto knife and a Dremel.
I'm pretty sure that X-Acto make a small miter box too for use with their razor saws, or you can always get a small one from Lowe's or Home Depot. If toy do a lot of tube cutting, that may be your best bet.... just a thought ;)

Gunner
NAR# 18493

tbzep
07-13-2011, 01:18 PM
I'm pretty sure that X-Acto make a small miter box too for use with their razor saws, or you can always get a small one from Lowe's or Home Depot. If toy do a lot of tube cutting, that may be your best bet.... just a thought ;)

Gunner
NAR# 18493
Those hobby mitre boxes have short walls. You could cut BT-5 and maybe BT-20, but anything bigger and the saw won't seat in the slots. A regular carpentry mitre box might do if the saw has fine enough teeth to make a clean cut once you get about half way down into the tube.

ghrocketman
07-13-2011, 01:48 PM
Liket that signature, Foamy.
I'm a card carrying member of that club.
MUCH more entertaining to be a grouch than one of those yay-hoos that sees a silver lining in everything ! :p

foamy
07-13-2011, 02:13 PM
Liket that signature, Foamy.
I'm a card carrying member of that club.
MUCH more entertaining to be a grouch than one of those yay-hoos that sees a silver lining in everything ! :p

Thanks. A line from a recent Dilbert strip: "Optimism is just another word for disappointment."

But seriously, dining, cocktails and bartenders used to be a lot better and the gov't was a lot smaller.

Bill
07-13-2011, 05:02 PM
I repaired my Centurion and find that I misaligned my replacement tube. It has about a 1/16" bow to it, right in the middle at the joint. I didn't check the alignment with a straight edge when I did it. It took the missus to notice and point it out to me. I'm disappointed.



It would not do to have a rocket with Peyronie's disease. If you end up having to cut it, here is my reliable way to cut tubes.

1. Slide a coupler inside the tube to support it while you are making the cut.

2. Use a sharp knife. This is as good a time as any to use a new blade.

3. I used to buy stamps by the roll. I wrap the waxed paper backing strip around the tube as a guide for the knife.

4. Cut slowly and do not try to do it in a single pass. I find that holding the knife stationary and rotating the tube gives me the best results.

5. Push the coupler into the end of the tube until it is even with the freshly cut end and gently sand the end.

6. Done.


Bill