Stanley/Bostitch air stapler rebuild

BobReeves · Jun 28, 2004

Seeing the air tool thread reminded me that I need to fix my air stapler. It is a Stanley/Bostitch T50S4 1/2 inch crown stapler which leaks air from someplace inside the ram assembly. I called the only place that repairs these things locally and was less than impressed with the conversation. Decided to tackle it myself but was wondering if anyone here might possibly give me a few pointers.

I have not yet attempted to take it apart as I was envisioning a "sprooing" and parts flying everywhere. I downloaded the exploded parts diagram from the web and it looks like it may just be a bad O-ring or something simple (hoping).

Anyone ever taken a air stapler apart that may give me a little insight on what to expect and the best way to proceed? I assume one would start with the 4 largish alen bolts that seem to hold the ram housing together???

Thanks,
Bob

DIYGuy · Jun 28, 2004

I have fully serviced mine. There are no springs on the inside. When taking it apart, be careful as there are quite a few precision machined surfaces.

Secondly, nothing is forced, when disassembled, it comes apart easily. That being said, it's not obvious how some of the pieces come apart.

Do not over oil it. Wipe everything down. If you over oil it, it will blow oil all over your floor. And yes, it should be only a few o-rings.

BobReeves · Jun 28, 2004

Thanks DYI,

Your post gave me to courage to tackle it, I am pretty mechanically inclined and normally wouldn't bat an eyelash but for some reason this air stapler made me a little apprehensive.

shvl73 · Jun 28, 2004

I'm not familiar with that model but, frequently you don't need the rebuild kit. A lot of models have a hard seal in the cap that seals against the cylinder, dirt gets pressed into this seal, preventing it from seating against the cylinder. Usually picking the piece of sand out of the seal & you're all set. Failed o-rings are common however & repair kits are cheap. Another common problem is the exhaust valve will stick in the cap leaving air leaking out the cap, cleaning & lubing it with light grease frees it up.

BobReeves · Jun 29, 2004

Pulled it apart this morning. Didn't see anything in the Ram assembly that looked bad so removed the trigger valve assembly and pulled it apart. Yep found the problem. There is a small orange tapered gasket that looks like it may be some sort of silicon rubber that disintegrated.

From what I can tell it doesn't seem to be part of the O-ring rebuild kit, just my luck that a common O-ring won't fix it. I emailed the factory asking about getting this gasket but my experience has been less than desirable when trying to get answers out a large company like this. A goggle search for parts mostly came up with the standard O-Ring kit, couldn't find a parts breakdown for the valve assy so this may be turn into a nightmare /forums/images/graemlins/frown.gif

shvl73 · Jun 29, 2004

What is the approximate age of the tool?
Does it have a green or white plastic trigger assembly cartridge?

BobReeves · Jun 29, 2004

I am not sure how old it is, I think maybe around 10 years. I bought it when I was building my previous shop and it has sat on a shelf for the last 8 or 9 years. The trigger valve assembly is green.

Thanks for trying to help.
Bob

shvl73 · Jun 29, 2004

I believe the trigger assembly is available as a whole assembly only. Bostitch offers it as one of their repair kits. The kit you are looking for is a TVA1. Call a tool repair center or a lumber yard that is a Bostitch dealer, they should have it in stock. I think the retail $ on the kit is a little high, I've seen it as high as $60.00, shop around if possible, I think dealer cost is below $20.00. If you have any problems, let me know.

BobReeves · Jun 29, 2004

Thanks for the help, will see if I can find it locally.

Believe it or not Stanley answered my email with a referal to a dealer in PA, no help on the part number but at least they answered /forums/images/graemlins/wink.gif