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Trenman
23rd October 2009, 03:10 PM
Forgive my ignorance in this matter. I have never used a reload before so I purchased a 38/120 1g motor to start out with. Below is pictured what I received.

http://i12.photobucket.com/albums/a218/lipower/rocket1.jpg

My question: I am rather baffled by the delay instructions. I dont seem to have a drill holder or drill bit in the kit at all, yet instructions say to use them to set the delay function.

http://i12.photobucket.com/albums/a218/lipower/rocket2.jpg

Honestly, maybe its because I dont have the parts, but the instructions seem vague. Could someone help me get on the right path? Cheers. L

Trenman
23rd October 2009, 03:12 PM
Also kindly excuse the poor resolution.

quickburst
23rd October 2009, 03:29 PM
You need to buy the DAT (delay adjustment tool) tool. Your vendor should have it.

I'm assuming you have the motor case?

hardinlw
23rd October 2009, 03:30 PM
It's a tool you buy separately to adjust the delay.

http://store.alshobbyshop.com/proxctidelaytool.aspx

new2hpr
23rd October 2009, 03:48 PM
I'm assuming you have the motor case?

Yes, remember the case. Quite a few have tried to fly the Pro38 reload without putting it in the casing. Results ain't pretty.

-Ken

Trenman
23rd October 2009, 05:55 PM
Yes I have the case. Do I NEED to mess with the delay to pass my L1?

Bazookadale
23rd October 2009, 06:02 PM
Yes I have the case. Do I NEED to mess with the delay to pass my L1?

Well it's an 11 second delay - is your rocket light enough to safely deploy with that long a delay? If not you need to shorten it!

stickershock23
23rd October 2009, 06:44 PM
I believe, BUT AM NOT CERTAIN, that The pro 38 delays can be shortened without the DAT tool, drill a hole 1/32" per second (about .030") that you need to remove from the propellant side of the delay.

Before you try this, someone from CTI please confirm that number.

Although I will say this, If you are going to fly any CTI reloads. the price of the tool is well worth it.

Good luck with you LI and enjoy!

Trenman
23rd October 2009, 07:30 PM
I ought to buy the tool. Everyone is sold out.... arghghhg

deandome
23rd October 2009, 07:51 PM
If you're launching w/a club of any size, SOMEONE will have one you can borrow.

Trenman
23rd October 2009, 10:47 PM
I'm sure thAt's the case but I've never done it before and I don't want to look completely stupid before my L1 cert for fear of not passing. I suppose I can just read and reread the instructions. I am quite sure it's a piece of cake for someone who has done it before. I never have but the instructions seem a bit vague.

stickershock23
23rd October 2009, 11:06 PM
Once you have the Pro DAT tool in your hand, it will all make sense.
It is very simple. no O-rings to mess with no seals, no spacers no grains to install..... Nothing. quick delay adjustment, slap the closure in... done.

Good luck

Trenman
23rd October 2009, 11:16 PM
I'll ask for clarification: do I understand correctly that a 2G reload actually has 2 grains plus a delay grain? I think that's correct.

So my question: does the igniter go all the way through the 2 grains and into the delay or does one have to be careful not to put it that far up, instead letting it rest into the 2nd grain?

n3tjm
24th October 2009, 12:24 AM
On the motors with the black poweder pellets, you want the igniter to go all the way up against the pellet. With the motors that dont have the bp pellet, you put the way up and then back it off about half an inch.

bobkrech
24th October 2009, 12:35 AM
Trenman

1.) Read and you will understand the directions! The Pro38 is as easy as dirt to use. Look at the pictures.

2.) Follow the igniter installation directions exactly. The igniter must extend all the way up to the delay grain that has a black powder starter pellet built in. If you use the supplied nozzle cap, it will hold the igniter in place. When the supplied igniter is in contact with the delay unit, the motor will light instantly.

3.) When you get to the field, find someone who uses Pro38 motors. Get him to guide and watch you assemble the motor.

4.) Borrow a PRODAT. Sim you rocket with the actual as built weight and use a Cd of 0.6 and 0.75 to determine the motor delay required. PRO 38 motors have the maximum delay as part of the identifier, The ProDat delay drill remove delay time from the delay grain and the amount remove is indicated on the tool.

For example if you use a motor with -13A at the end of the designation, and you need a 6 second delay after burnout according from your sim, you set the tool to 6 - 13 = -7 seconds and drill out the delay until the tool bottoms out. It's really that simple.

5.) Make a check list of what you have to do before you go to the field and follow it. Check off each item when you do it and you won't have a stupid mistake wreck your cert flight.

6.) Take a deep breath, and relax. With the mentoring of an experience person, you flight will go well.

Good luck.

Bob

Jeroen_at_CTI
24th October 2009, 12:53 AM
I believe, BUT AM NOT CERTAIN, that The pro 38 delays can be shortened without the DAT tool, drill a hole 1/32" per second (about .030") that you need to remove from the propellant side of the delay. Before you try this, someone from CTI please confirm that number.

Please use the delay tool. It is a lot more accurate and the same tool can be used for all Pro38 and Pro29 reloads (as well as Loki and AT and....).

The actual number is closer to 0.040" / s, btw.

Jeroen

stickershock23
24th October 2009, 12:56 AM
Please use the delay tool. It is a lot more accurate and the same tool can be used for all Pro38 and Pro29 reloads (as well as Loki and AT and....).

The actual number is closer to 0.040" / s, btw.

Jeroen

Most definitely, I was just curious to the number... XXXinch = XXX seconds

The tool is totally accurate.

MarkII
24th October 2009, 06:31 AM
Instead of having to produce multiple versions of each Pro38 and Pro54 reload with different set delays, CTI provides all of them with the maximum delay installed. You can then shorten the delay to the interval that you require. Not a bad approach to the issue of providing the user with a range of delays for a given motor. I'm not as familiar with their Pro29's, but I suspect that they carry this feature as well.

MarkII

cjl
24th October 2009, 01:37 PM
Correct - I'm pretty sure the 29's use the 38mm DAT with an adapter.

blackjack2564
25th October 2009, 01:34 AM
I ought to buy the tool. Everyone is sold out.... arghghhg

Wildman has them in stock.

blackjack2564
25th October 2009, 01:37 AM
Correct - I'm pretty sure the 29's use the 38mm DAT with an adapter.

Yep they do.