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On my NEW 10-fcp-k I noticed that the pre drilled and tapped scope mounting hole in the receiver look to have the same black finish in the threads as the rest of the receiver.
Do you guys recommend chasing the treads out with a 6-48 tap before installing my new base a screws?
Thanks
I would, if you have a tap handy. Sometimes the holes fill up with gunk during the blasting process.
Just to clarify, don't use a tap, use a thread chaser. There is a diff. The chaser won't remove any metal, they only clear the theads.
Can you give me a source for 6/48 "thread chasers" ?
Around here Lamb industrial. The best thing to do is ask your local machine shop, were they get their supplies.
Would you like to point out where Lamb has 6-48 taps or "chasers" listed?
http://www.americastoolcrib.com/cgi/CGPTBROWSE?PAMENU=1
I have no idea, I had a local machine shop friend of mine order it. But that was years ago. Now I just use pipe cleaners and alcohlol, to clean out the threads.
I'm not sure I understand the not using a tap to clean the threads. If it removes metal then it needed to be tapped...no?
It would be like cleaning your barrel with the button they rifled it with. Experts have said, retapping can weaken the threads by 50%. If you have crud in the threads, and use a tap, there is no tolerance between them. Where then will the crud go, yup in between the two, and act as a grinding compound.
Not really.
This is why taps have flutes so the crud has a place to go so you won't damage the threads.
The flutes are there so the metal has somewhere to go. I didn't make the rules. I just follow them. Have you ever seen a bolt that was cleaned with a tap. Shiney and sharp. Not good. You can do what you want, I'm just trying to help. They wouldn't make chasers if there was no application for them. I'll give another example. Thompson Center has a breech plug shaped thread cleaner, it's made of plastic. Can you emagine cleaning the breech plug threads in the barrel, with a tap.
Sure haven't because you can't do anything to a bolt with a tap.Quote:
Originally Posted by r29l20
You assume that this is a matter of suitability, I'd argue that it's one of cost. A metal plug tap that size would make up a substantial portion of the cost of the rifle. Repeated use of a metal part over time would likely wear the threads out but a single use shouldn't hurt anything.Quote:
Thompson Center has a breech plug shaped thread cleaner, it's made of plastic.
Cleaning threads and cleaning up threads are two totally different things. Cleaning threads means *removing* foreign material from them. Cleaning up threads means *fixing* threads that have been boogered up in some manner. In the first instance, I really want to remove material and unless the threads are boogered as well, the material being removed shouldn't be the material of the threads but rather only the foreign matter. In the second case, you are correct, I want to "iron out" the messed up part and press the displaced material back where it should be. This should ideally be done on a clean thread or the foreign material will get ironed into the surface and trash the threads. The first can be done with a tap (special taps are made specifically for cleaning inside thread that have a larger than normal debris channels but are no less sharp than a thread cutting tap), the second with a thread restoring tool.
heliotaxi
So let me see if I understand.
In my situation the threads are not boogered up as Savage applies the black finish to the receiver after the scope mounting holes are drilled and tapped into the receiver and that black finish is what gets into the holes and threads making threading a screw into these holes pretty tight.
So what I did was take a 6-48 tap with some oil and cleaned out the black finish material from the holes and threads.
I watched for metal shavings as I did this and saw little to no shavings what so ever.
So now the threads look nice a clean the the screws thread into the receiver nicely.
I searched far a wide for a 6-48 "thread chaser" but couldn't find such a animal so this is why I went with a 6-48 tap.
Have you ever seen a bolt that was cleaned with a tap.[/quote]Sure haven't because you can't do anything to a bolt with a tap.
heoltaxi are you really that thick? You know what I meant. OK I'll spoon feed it to you a die. better? I don't know why some people have to get on a forum just to argue. Probably to make up for some short comming. Everyone forget what I posted. I have know idea what I'm talking about. :-X Sorry.
Sure haven't because you can't do anything to a bolt with a tap.Quote:
Originally Posted by r29l20
heoltaxi are you really that thick? You know what I meant. OK I'll spoon feed it to you a die. better? I don't know why some people have to get on a forum just to argue. Probably to make up for some short comming. Everyone forget what I posted. I have know idea what I'm talking about. :-X Sorry.
[/quote]
Was the sarcasm really necessary?
NO tap or die is cut the same...very, very close, but not exact. There is so many differences in machines, tolerances, etc, etc...that there IS a difference in the threads cut or chased.
Sarcasm feeds sarcasm. I say if you can't take it don't dish it out. It's just that easy. Try being respectful, see how that works. I'm not gonna keep this going anymore, like I said before, forget I said anything. I'm sorry I posted anything. Let it go already.
And what you did is fine. Engine builders do pretty much exactly the same thing to all the threaded holes in an engine block when it comes out of coating so the head bolts etc... thread into the block correctly.Quote:
Originally Posted by sliderspal
::)
I am an aircraft mechanic by trade. I have noticed on the Snap-On truck that I buy tools from, that there are no "thread chasers" smaller than 10-32. At least in the kit that I bought. I inquired as to whether smaller chasers were available, and was told they were not. I was told that the thread chaser is basically a hex-headed bolt with grooves cut parallel to the shank to allow the crud a place to accumulate as the chaser is run into the hole; just like a tap. The chasers are sized to remove debris from the space in between the peaks and valleys of the threads. I would surmise that a fella could make his own thread chasers by cutting grooves in a screw, and then cleaning said screw up with a die. Just my .02, but since there seems no solution to the problem yet, I thought I might take a stab at it to help a guy out.
Respectfully,
Kevin