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Fowler Xtender Bore Gage | Product Overview

Hey everybody it is Nick here at Higher Precision again and today we're going to be reviewing the Fowler Extender Bore Gauge, part number 52-646-400.

Today we're going to be reviewing the Fowler extender bore gauge part number 52-646-400. The great part about this bore gauge here it is essentially the two most popular ranges of bore gauges all wrapped into one. For those of you that are familiar with bore gauging, you will know that a 1.4-2" and then 2-6" are by far the most popular range bore gauges. Fowler hit the nail on the head when they came out with the extender sets. It the two most popular bore gauge ranges all wrapped into one. So let's take a look at this one here. What does it include and what are the specs?

This one includes a .0005" indicator on here. It's going to get you down to a measuring depth of approximately 9.5" and the total range of covers is 1.4-6.0". Now within the kit you are going to open it up and let's quickly explain what everything is. You are going to get two different feet for the bore gauge use. The smaller foot here is actually used for the anvils when measuring from 1.4-2.0" and then you have a larger foot here that is used when measuring from 2-6". Also included in the kit you have a two inch extension, a manual, you have a set of four spacers, the dial indicator & shroud (.0005" Graduations on here) and it does have the tolerance indicators as well. On top of that you are going to get all of the carbide tipped anvils to be able to let you measure the whole range of 1.4-6.0"

Now we do get a lot of phone calls when you do sell this set that people call up and they think that they're missing anvils because it does appear that there are three missing anvils here. However, the smaller anvil here, the two inch anvil is actually already pre-loaded into the 2-6" foot and the smaller the 1.4" anvil is already pre-loaded into the 1.4-2.0" foot. So the only one that is missing and technically should be missing is this large anvil here and the reason is Fowler they kind of create a universal bore gage case that they can use for a wide variety of their bore gauges just so they don't have to create a custom case for every bore gage. So this large anvil should be missing - definitely not included with this bore gauge set. So let's take a little bit deeper dive I'd like to show a few of you that have any questions on how to actually assemble the bore gauge and how to correctly set it in a setting ring.

So now I'm going to take a couple minutes to quickly explain to you folks that are interested on how to actually assemble the extender bore gauge yourself. With that you are going to need a good jeweler's screwdriver and to set it up for the purpose of this demo today we are actually going to be setting up the bore gauge to measure a 1.6" setting ring. For that sake I know I'm going to need the smaller foot for 1.4-2.0" and if I'm looking at the anvils here all the anvils are labeled and there's actually an anvil labeled 1.6" which is exactly what we're trying to set so I'm actually going to use that anvil in the foot of the bore gauge. So let's start putting this baby together and see how it goes. The first thing I'm going to do is remove the foot that measures from 2-6".

I'm going to take time just quickly remove this here and put on the smaller foot. So I remove that foot and I'm going to put the smaller foot from 1.4-2.0" on here and once I have that secured on I'm actually gonna remove the smaller anvil and put in the 1.6 anvil that we do have here. Alright so there's a little knurled knob you can just unscrew that, pop out the 1.4" anvil and I'll put that back in the space so I make sure I don't lose it and I'm gonna put in the 1.6" anvil. Now before I actually put on the 1.6" anvil I wanted to quickly explain the purpose of the spacers here because a lot of people do call up questions on what to actually do with the spacers. Now the point of the spacer is if you need it it's not always needed, the spacers can go in the backside of the anvil and what that actually does is a spacer will actually extend the anvil out just a little bit more so they aren't always needed but you do get four different size spacers in there in case you are going to need them here. Alright so now we have the smaller foot installed on the bore gauge our next step is to actually put the indicator on the bore gauge itself and this is where you're going to need the small jeweler's screwdriver. There are two screws right there we're just going to quickly remove these two screws and I have been thinking about possibly working on my singing voice or whistling to help get through the quiet times here. Alright, so I am going to pop that part off, and there is a little plastic cover that actually protects the indicator, you can just remove that there. Now we are going to install the bore gage into the indicator. Now on the top of the bore gage you are going to see a black knurled knob and you can just back off on that, just a little bit. We are going to insert this into the bore gage. The needle is moving so I know that we made good contact there. Once I have installed that there, I am going to tighten the black knurled know until it is snug and then I am going to put on the black protective cover, tighten the two screws and we should be good to go and ready to start measuring here.

Grab my jewlers screwdriver and tighten these two screws. You don't want to go to tight and I don't recommend using an electronic screwdriver either, just get a cheap inexpensive handheld jewlers screwdriver. I think we are good to go with the assebmly there. We do have the bore gage assesmbled, the indicator is snug, we have the foot from 1.4-2.0" in there and the 1.6" anvil. Before we start measuring we just want to make sure the bore gage is going correctly. The way we can do that is if you look at the foot of the bore gage you have two centralizing wheels. Now within the two centralizing wheels there is actually a little pin and that is actually does all the measureing on a bore gage. So quickly I am going to depress that pin to make sure the gage is measuring and I can tell when I push it in and out the needle is moving so I know we have it set up correctly. So now we are just going to switch up camera views and I am going to teach a couple of you on how to actually set this gage up in a setting ring.

The Extender bore gage has been assembled correctly and now we actually have to put it in a 1.6" setting ring to set the bore gage prior to use. Now when we put this in the setting ring we are going to be doing two different things. We are going be rocking the bore gage back and forth specifically looking for the reversal point but also when we rock that bore gage back and forth inbetween the two centralizing wheels we briefly mentioned before is the pin. This is the pin when depressed that actually does the measuring. So when you are rocking this bore gage back and forth you do want to make sure that the pin is being depressed. So lets put it in the ring and set the bore gage here. So we are going to put the gage in the ring and start rocking it back and forth. Again you are going to do two things here. We are going to make sure the pin is being depressed which it is. I can tell the needle is moving. The next thing we need to be focused on is the reversal point. So we are rocking the bore gage back and forth in the setting ring to try to find the reversal point. So I kind of keep it at a hight point, I am going to be rocking the bore gage and if you want the needle it goes one way....one way....one way....one way....one way. It hits a point called the "reversal point" and then is starts going back the other way. If you look I have already rotated the bezel on the indicator so now this bore gage is perfectly set up for a 1.6" dimension.

This bore gage is also offered with a .0001" indicator as well as an electronic model if you are interested. That wraps up our review on the Fowler Extender Bore Gage. This bore gage truely is two bore gages wrapped into one and is sold at a great price point. If you do have any other questions you can feel free to reach out to us at HigherPrecision.com and until next time, we will see you again.

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