enock111

I would like to know 3 things about this tool if anyone can help.

1. What is the tool called
2. What is the Park Tool name or number
3. What is it used for

Thanks for your help!

Troul 

A gauge used to ensure the drop out is parallel during spacing. It's missing the alignment cold setting tools.

CliffordK

It is a caliper.

Apparently sold as part as the FFG-1

https://www.parktool.com/product/fra...auge-set-ffg-1



It is similar to shop calipers (woodworking/metal working), but it appears to be a much cheaper quality.

enock111

Your the man! I've been trying to figure this one out for a long time now!!

Andrew R Stewart 

Typically used in the shop to compare axle widths when looking at replacement wheels. Not really used much when aligning a frame/drop outs (the jaw tips point the wrong direction). Andy.

JohnDThompson 

Yes, a caliper for measuring the over-the-locknut spacing on a hub. You open it so the ends touch both locknut faces, then bring it to a ruler to measure.

WizardOfBoz

I think that with this basic design you can measure both ID and OD - you can reverse them. Normally you'd use a straight-arm caliper for ID and the curved for OD, but you probably could get them to work. The picture below shows a curved arm caliper overlapping to measure ID. And the straight armed one is not reversed - opposite what I'd expect.

In any case, the OP's Park Tool calipers are curved so you can measure locknut to locknut on wheels, but can be reversed (overlapped) to measure ID such as dropout to dropout dimensions in frames.

dsbrantjr

I use these for measuring axle and hub width and similar: https://www.harborfreight.com/6-in-l...per-63714.html regular calipers work fine for dropout width.

coupster

What did you do? Buy a box of old tools and now you're trying to figure out what to do with them. Multiple posts of tool identification.

enock111

I collect and try out different bike tools especially old ones. I own some of the more obscure ones from Park Tool and there is very limited information on the web about some of them.

CliffordK

That type of caliper is designed not as much for measuring, as for compariing two objects. It could probably be overlapped as above, but not necessarily needed.

So, one takes a measurement of say the hub, them carefully moves over to the dropout to measure & compare.

Of course, one can also measure the calipers. Especially if it has some kind of locking mechanism.

The deep throat would benefit getting around spokes, hubs, and perhaps small freewheels/cassettes.

WizardOfBoz

Agree with Clifford: these types of calipers might be set using a standard dimension (a stack of gauge blocks or a "known good" part) or a ruler and used on a lathe to do a quick check on a part. So its use was mainly as a comparator. When the part was close to dimensions, a more accurate (e.g. micrometer) could be used. That's not to say that very clever machinists didn't achieve incredible results with this type of caliper. Some older vintage models had a thumbwheel that would allow you to adjust these to 0.001 to 0.002 inch precision. Here's a pick of this type. The large thumbwheel on the pivot locks the arms and the small thumbwheel on one arm allows you to wiggle one leg to get extra precision.

For our purposes, though, you could measure the locknut to locknut dimension (or the dropout to dropout dimension) using this thing, measure it with a ruler, and compare it to a compiled list like Sheldon's. 1mm or so is probably close enough to tell you which standard dimension you have.