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Hello. My Ernst Kaps upright is undergoing some restoration which includes a new set of tuning pins. Their original diameter size was a little bellow .276"
I tried different diameters and found out that the new set should have .282" to achieve the desired tightness/torque.
I am not sure about the tuning pin reamer diameter. What would be your suggestions?
Thank you very much in advance.

If you are going to ream, you will probably have to move up one size pin.

If the feel is good, just drive in the new pins.

Otherwise some use a gun barrel brush to scrub the hole. If it's a really hard maple pin block, the gun brush won't do much.

Hello Keith.
Thank you very much for your kind reply.
The original pins have .264" diameter.
When I put the .282" pin on the loosest holes, the feel is good, so I considered reaming the holes that are already tight with the original pin.
Which reamer diameter do you consider suitable for that task?
.010" less than the new pin is OK?
I will also try the gun barrel brush before reaming. Very good idea!
Thank you very much again.

In your case it would be best to use an adjustable reamer and set it about .012" less than your pin diameter for a start. Depending on the condition of your reamer and your technique this is a safer route and you can add a bit to the reamer size by 2-3 thou increments if its not enough...sometimes even doing a second pass will work. If you haven't done this before your first couple holes might end up a little bigger than expected until you get the feel for it. Because the top of the hole is usually bigger make sure you line up the reamer at the proper angle when you start or you could end up reaming some material off center before the reamer's lead chamfer fully centers itself and the reamer body gets everything lined up. Good luck with your efforts.

Hello Emmery. Thank you very much. I will follow your suggestion. I did not know about adjustable reamers. I will let you know the results.

I use a center pin as a reamer. Put the pin between two files and rough it up real good. Then place it into a center pin chuck equipped with a handle, or better yet, put it into a power drill if your doing entire sets of flanges.

As you start the job, use the same size pin to ream, as you are using to re-pin. The trick is to set the drill speed and the time you spend reaming each bushing and be consistent once you find the right formula. This will vary depending on bushing felt density and contamination from the old center pin. But once you get going, the reaming should go very quickly. If necessary, change the reaming pin to a different size, but I rarely do that. Keep a brass brush handy to clean the reamer every once in a while.

Once you get set up, you can re-pin an entire set of flanges in 3 - 4 hours. You can also treat each bushing with teflon powder, by dipping another roughed-up pin into the powder and inserting that into the bushing.

There's some other tricks to use to do the job faster if you're interested.

Ah Randy. Take note. This thread is about pin block reaming not flange bushings.

I just bought a .272" reamer for the .282" new tuning pins. I hope I do well with that reamer. I will let you know about the outcome.
Any suggestion is wellcome.

Did you purchase a T- handle for the reamer? For best results this work is done by hand reaming. See photo link here…..

http://picasaweb.google.com/silverw...Gv1sRgCJDcpYDJiOXuEA#5372558979906590594

I'll be sure to have that first cup of coffee before reading the thread next time.

Thanks for kicking me in the head. You saved my wife the trouble.

Hello Randy. Thank you very much anyway. Your post shows willingness to help others.
Hi Dan. I have the handle. Do you agree with the reamer size I choosed?
Thank you very much.

Good one.The reamer size is fine. Good luck with the job.

Oh a couple of more things I should mention, if this is an adjustable reamer you are using turn CLOCKWISE ONLY going in and out. If you reverse and turn counter-clock wise, the adjustable nut on the bottom could unwind and the reamer could expand and you will have trouble getting it out without making the hole too big.
And remember both hands on the T-handle. If you get lazy and try to turn with one hand or a socket on the top you could snap the end of the reamer like I have done previously………..

At the risk of exposing my human frailties once again, I must share my experience with pin block reaming. I found, at least in my case, that it is very easy to over-ream a hole. I used a one size smaller, reamer to new tuning pin - don't recall the exact diameter, but perhaps it was a size #3 reamer for #4 tuning pins.

The speed of the drill and the amount of time spent in the hole will make a difference in the results.

I wonder if using a pin two sizes larger than the reamer, and simply reaming the heck out of the hole may be better - more consistent?

Ever since that experience, I have only done pin block replacements when I restring. Unless the block is as-new, then I recommend using the next size-up tuning-pin without any reaming.

I hope that this post made sense and offered some value to this thread.

Dan is correct about only going clockwise, in fact no reamer (even not-adjustable ones) should ever be turned the other way while in contact with the work as a general rule, it prematurely dulls them. I don't use a power tool for reaming because the reamer heats up and expands making for a slightly looser fit on successive holes. There is also the risk of seizing in the hole if the end of the reamer's slightly dull or the body heats up bigger than the hole. You do not want to be fishing seized tool steel/carbide out of a hole.
Delignit and other blocks with lots of glue/layers give the pin a creepy feel if a excessively hot tool is run through it or even when a pin is wound out too fast with a power drill. I think the heat spreads the glue from the laminates onto the wood contact area changing the feel of the pin. A lot of unfair criticism is leveled against these multi laminates because of this. Brushing them out with a gun barrel brush after helps expose the end grain and cleaning out residue.

I fixed my earlier post.

Why can't I find the edit button?

The edit button has a time limit.

Of about six hours from what I understand Randy. Then after that, you cannot edit your postings.

When I used a reamer with a drill, many years ago, I was not satisfied with the end result.
Any time I find it necessary to ream, I do it by hand. That way, you have much more control.
Also don't do them all without checking the results.
Do some test pins.
It is much easier, to have to go oversize with just a few pins.

Randy, Dan, Emmery and John.
I appreciate very much your helpful insights regarding this task. I expect my tools and new pins to arrive in a couple of weeks. I will take special attention to all these details. Thank you very much for your assistance.
Enrique