How to determine the right hight for Bevel Gear when Shimming!?!

Superstuco · August 9th, 2009, 17:52

Hello All!

After my originla g&g spur gear lost a tooth last month, I finally ordered a full set of modify gears and changed them all. After dismounting the gearbox, i cleaned and lubricated the thing and then proceeded to do my first shimming.

It looked good, but when I remounted the gearbox, I could do the full cycle (air nozzle retracting, pressure comming out) BUT it also makes that atrocious teeth grinding noise like if some gears were not touching correctly...

I cannot find where that noise comes from... evrything must be at least making contact roughly the right way if the gearbox cycles correctly... But OMG that noise...

I wonder how to determine the right height for the bevel gear to make contact with the motor's head when shimming...

Do you people have any trick? My first shimming FAILED (aparently) and was really scary!!!

Styrak · August 9th, 2009, 17:59

Could just be your motor height as well.

Superstuco · August 9th, 2009, 18:02

I screwed around with the height a lot and none seem to work.. they all do SCRRRRRRRRrRrrrRRrRRR...

I tried to plug the motor directly in the gearbox by holding it firmly with only the three gears inside the gearbox and the gearbox screwed shut, and even with only these four parts interacting I still get this SCRRRRrrRRRReaching noise.

lemegacool · August 9th, 2009, 18:05

are your gears spinning freely without the cyl/piston assy, gears could rub against each others...

Superstuco · August 9th, 2009, 18:24

yeah everything spins freely but firmly with everything removed... Actually, even with the pistons and everything in it moved ok...

ShelledPants · August 9th, 2009, 18:28

Quote:

Originally Posted by Superstuco

yeah everything spins freely but firmly with everything removed... Actually, even with the pistons and everything in it moved ok...

Put the gears back in the shell with the bushings etc... without the piston or cylinder. Now screw the shell back together with all the screws as if you were about to put it back in the gun. Now try and spin the gears by putting your finger in the cylinder area and nudging the gear. If they don't all spin easily, as in, a nudge and they all move a half cycle, then you've got too many shims somewhere and you need to re-shim. Often just holding the shell closed will not provide the same pressure as the screws and the gears will bind when fully assembled.

It will be VERY frustrating. Take your time, take a break, eat something, go for a walk and come back to it with a clear head.

Good luck.

Superstuco · August 9th, 2009, 18:30

Quote:

Originally Posted by ShelledPants

Put the gears back in the shell with the bushings etc... without the piston or cylinder. Now screw the shell back together with all the screws as if you were about to put it back in the gun. Now try and spin the gears by putting your finger in the cylinder area and nudging the gear. If they don't all spin easily, as in, a nudge and they all move a half cycle, then you've got too many shims somewhere and you need to re-shim. Often just holding the shell closed will not provide the same pressure as the screws and the gears will bind when fully assembled.

I did EXACTLY that and when it's closed everything moves smoothly when i move the sector gear with my finger...

What scares me is that by adjusting everything closing trying it and sCRRRRrrrrRRRRReeching and reopening and adjusting.... the gears will eventually loose teeths maybe before i learn the process and successfully find the problem...

lemegacool · August 9th, 2009, 18:31

Quote:

Originally Posted by Superstuco

yeah everything spins freely but firmly with everything removed... Actually, even with the pistons and everything in it moved ok...

there must be no (or very little) play between gears and their face should not toutch each others... shimming is an art! lol and as mentionned motor height is susceptible of causing that grinding noise. usually when its a grinding noise it's because the motor sits too far from the bevel...

ShelledPants · August 9th, 2009, 18:33

Quote:

Originally Posted by Superstuco

I did EXACTLY that and when it's closed everything moves smoothly when i move the sector gear with my finger...

What scares me is that by adjusting everything closing trying it and sCRRRRrrrrRRRRReeching and reopening and adjusting.... the gears will eventually loose teeths maybe before i learn the process and successfully find the problem...

This is the exact reason gun doctors cost so much: It's a hard process to learn, and costs a lot of money to learn. You may want to save yourself some time and money and take it to a professional.

lupo · August 9th, 2009, 18:59

Other then what has been suggested the only other thing I have to add is what kind of modify gears are they? I know that systema super torque up (helical) gears are super noisy just due to the design.

Styrak · August 9th, 2009, 19:00

Quote:

Originally Posted by ShelledPants

This is the exact reason gun doctors cost so much

Gun doctors don't cost that much...

Quote:

Originally Posted by lupo

I know that systema super torque up (helical) gears are super noisy just due to the design.

Helical gears should be quieter if you shim them right.

Superstuco · August 9th, 2009, 19:28

yeah well...

I'll screw around a few more times... then i guess i'll get it right, OR the gears will break...
I really want to learn how to do this right...

lawldragon · August 9th, 2009, 20:24

This is the guide I use to shim my Gearbox

http://www.arniesairsoft.co.uk/?filn.../shimguide.htm

I actually encountered the same problem when I was shimming mine, the problem was that a shim got stuck on my bevel gear and I didn't notice it which cause the bevel gear to press down on the motor. It still spinned well without anything attached just like in your case. I also applied some white lithium grease to the shim and the gears to make sure everything spinned nice and smooth then finished it off with a spray of silicon.

Hoped I helped

voorhees -FWA- · August 10th, 2009, 18:46

this is a more detailed way to shim your AEG...
shim your AEG
it's long winded, but you did say you wanted to learn how to do it properly...
enjoy!

BeAcH · August 11th, 2009, 02:00

What are you working on, and when you drop your motor into your grip does it have free play inside of the grip. Sometimes when the motor is too tight inside of the grip it wont adjust itself properly. It will just sit and get stuck in one area, hence why when you try to adjust it nothing works.

If you cant get it, ill fix it for you for free, you just have to pay for shipping back and forth. Dont like seeing airsofters out of the field cuz of problems like this.

Cheers

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August 9th, 2009, 17:52	#1
Superstuco Trader rating Join Date: Jul 2009 Location: Ste-Therese,Qc	How to determine the right hight for Bevel Gear when Shimming!?! Hello All! After my originla g&g spur gear lost a tooth last month, I finally ordered a full set of modify gears and changed them all. After dismounting the gearbox, i cleaned and lubricated the thing and then proceeded to do my first shimming. It looked good, but when I remounted the gearbox, I could do the full cycle (air nozzle retracting, pressure comming out) BUT it also makes that atrocious teeth grinding noise like if some gears were not touching correctly... I cannot find where that noise comes from... evrything must be at least making contact roughly the right way if the gearbox cycles correctly... But OMG that noise... I wonder how to determine the right height for the bevel gear to make contact with the motor's head when shimming... Do you people have any trick? My first shimming FAILED (aparently) and was really scary!!! Last edited by Superstuco; August 9th, 2009 at 18:06.. Reason: forgot a word.

August 9th, 2009, 17:59	#2
Styrak Trader rating Join Date: Jan 2007 Location: Saskatoon, SK	Could just be your motor height as well. __________________ Airsoft Sales and Repair/Upgrade Services

August 9th, 2009, 18:05	#4
lemegacool Trader rating Join Date: Aug 2008 Location: notre dame des prairies /quebec	are your gears spinning freely without the cyl/piston assy, gears could rub against each others... __________________ member of fire team NOM. my other regular forum: www.toyotanation.com / gen3,gen4 camry

August 9th, 2009, 18:02	#3
Superstuco Trader rating Join Date: Jul 2009 Location: Ste-Therese,Qc	I screwed around with the height a lot and none seem to work.. they all do SCRRRRRRRRrRrrrRRrRRR... I tried to plug the motor directly in the gearbox by holding it firmly with only the three gears inside the gearbox and the gearbox screwed shut, and even with only these four parts interacting I still get this SCRRRRrrRRRReaching noise.

August 9th, 2009, 18:24	#5
Superstuco Trader rating Join Date: Jul 2009 Location: Ste-Therese,Qc	yeah everything spins freely but firmly with everything removed... Actually, even with the pistons and everything in it moved ok...

August 9th, 2009, 18:59	#10
lupo Trader rating Join Date: Dec 2001 Location: vancouver	Other then what has been suggested the only other thing I have to add is what kind of modify gears are they? I know that systema super torque up (helical) gears are super noisy just due to the design.

August 9th, 2009, 19:28	#12
Superstuco Trader rating Join Date: Jul 2009 Location: Ste-Therese,Qc	yeah well... I'll screw around a few more times... then i guess i'll get it right, OR the gears will break... I really want to learn how to do this right...

August 9th, 2009, 20:24	#13
lawldragon Trader rating Join Date: May 2009 Location: Richmond, BC	This is the guide I use to shim my Gearbox http://www.arniesairsoft.co.uk/?filn.../shimguide.htm I actually encountered the same problem when I was shimming mine, the problem was that a shim got stuck on my bevel gear and I didn't notice it which cause the bevel gear to press down on the motor. It still spinned well without anything attached just like in your case. I also applied some white lithium grease to the shim and the gears to make sure everything spinned nice and smooth then finished it off with a spray of silicon. Hoped I helped

August 10th, 2009, 18:46	#14
voorhees -FWA- Trader rating Join Date: Oct 2008 Location: Estevan, Saskatchewan	this is a more detailed way to shim your AEG... shim your AEG it's long winded, but you did say you wanted to learn how to do it properly... enjoy!

August 11th, 2009, 02:00	#15
BeAcH Trader rating Join Date: Jun 2008 Location: Fort Saint John BC	What are you working on, and when you drop your motor into your grip does it have free play inside of the grip. Sometimes when the motor is too tight inside of the grip it wont adjust itself properly. It will just sit and get stuck in one area, hence why when you try to adjust it nothing works. If you cant get it, ill fix it for you for free, you just have to pay for shipping back and forth. Dont like seeing airsofters out of the field cuz of problems like this. Cheers __________________ Live for nothing, or die for something They can have my rifle when they can pry it from my dead cold fingers

How to determine the right hight for Bevel Gear when Shimming!?!

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