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BBGun Bob · Veteran Member

As most of you already know this Chinese mystery wood is very soft. Screw holes are stripped out in a heart beat with very little pressure to the screw.
I have found by putting Devcon 5 minute epoxy down the stripped out hole about 1/3 full then put a little lube on the screw threads and run it in about 3/4 of the way down the hole and let it cure about one hour(the longer the better) you will have a new hole that is both repaired and stronger than it was originally.Now you can go ahead and tighten up the screw.
Just a little message to save you from ending up with very large over sized screws : To much epoxy and you have it comming out all over the place when you put the screw in.
SHOOT SAFE SHOOT STRAIGHT ! Or you'll shoot your eye out!!!
(below) 1971 Crosman 1100 TrapMaster

AirGunEric · Site Admin

I've had to repair a couple of "Chinese mystery wood" stocks, but have used plain outdoor wood glue and then reinforced the hole with a washer. I've also used outdoor wood glue to put a broken stock back together (clamping it firmly for 24 hours to dry) and coating the inside of the stock/bedding area with the glue as well. I think the mystery wood stock I repaired like this is actually stronger than it was beforehand.

BBGun Bob · Veteran Member

Eric,
The reason I use the epoxy is curing time.If I remember correctly it takes wood glue forever to set up.I guess I am a little impatient when having to wait for something to cure.In this case I'm shooting again in one hour!
I am a retired welder and like cure time instant and hot . Wink

Me on my 1974 Super Glide Chopper

AirGunEric · Site Admin

1974 SuperGlide? No "rubber band" drive system and "Evolution" tech for you, huh? Wink

That's alot of friggin' pipe out back! Do the tips stay hot enough where someone could burn themselves if they touched them? Who did all that custom work (forks, tank, pipes, wheels- and I can't really make out the seat)? Ever do anything to improve it's factory output (what was it, about 60bhp or something)?

broommaster2000 · Moderator

Listen, I might be nagging, but going off-topic in your own topic so much... Isn't that a bit unnapropriate? I mean, okay, a talk about mistery wood and fixing it I can understand, but what does that trapmaster and chopper have to do with the topic.

I've probably done this myself, but mistakes often reveal themselves when you see them with others.

In other words, let's all try to keep it a bit of a tidy forum.

And in the meanwhile, great gun, great motor. I'm not all bad, but this just ain't the appropriate topic. Wink

By the way, please criticize my posts if they are innapropriate. Exclamation

AirGunEric · Site Admin

If the topic goes askew, and stays askew- posts can be separated into their own topic in other areas of the forum- so it's really not that big a deal, IMO. If this thread becomes more one of "HD motorcycle talk" then it will be split. However, it might also come back to mystery wood repair as well.

What is your contribution to the "mystery wood" repair here, Broom?

broommaster2000 · Moderator

Nothing, and I think your reply is satisfactional and reasonable.

Edit: I'd love to know more about chinese mystery wood since I am going to get myself a QB88. Maybe there was a bit of impatient-ness in my previous posts here.

Alstone · Moderator & Site Supporter

I've had the same problem with Chinese wood, my QB 78 butt plate fell off because of wood screws that had striped out the hole. My solution was to put an Armstrong Heli-Coil insert in the butt wood, this tool has a breach like a gun into which you insert a special spring shaped like the thread you want to put in, as the spring is screwed through breach it is compressed, the wood is taped out with a special tap to match the spring, as the spring passes from the breach to the wood it is kept in compression by the twisting motion of the bolt which has a slot on the end to engage in the spring, as soon as the spring is to the depth required the the bolt is withdrawn and the spring expands to the correct thread size.

With this system you can replace wood screws with Allan screws.

Insert tool kit

This may seem a bit complicated but this system is used to replace spark plug threads in Cars and Motorcycles

Al

AirGunEric · Site Admin

Al's Heli-coiling Chinese mystery wood! Now I've seen it all! That would be the strongest part of the gun once done.

I'm more accustomed to using Heli-Coils on cast iron and aluminum engine blocks than on Chinese airguns. Mr. Green

broommaster2000 · Moderator

It looks fluffy. Mr. Green

Say. Might it be a plan to make a good tutorial out of that one? With pictures?

I'm sure that if you just take a piece of wood and show how it's done the needed materials I'm sure the message'll get trough.

Alstone · Moderator & Site Supporter

It's not worth a tutorial Broom, if you haven't allready got the tools they are two expensive to buy for a couple of holes, and if you have the tools then hopefully you will know how to use them, as Eric says they are mostly used in the motor trade.

But if your still intrested on how it works Broom I'll post a tutorial in Maintenance and Modification.

Al

broommaster2000 · Moderator

I got two left hands, so a tutorial would be great. Besides, it's also better to find if you are new on the forum. Mr. Green