Amesja

The fact that not even Park has a cotter press in their current lineup even though there are plenty of cottered cranks still out there gives a lot of credence to the efficacy of the hammer method.

I do know that as long as I had $20 and a drill motor/bits I wouldn't use a hammer if I could buy the HF press (or one of the other chain breakers. I'll never use a hammer again unless the press fails me.

noglider 

They used to make one, and it worked great. They don't need to make it any more, because there's very little demand for it.

Amesja

I've seen pictures of one but never one in person. I think the only person making a cotter press at this time is the guy at Wheelsmith. There must be somewhat of a demand for it or maybe just a demand for neat high-end stuff because after about $70 in purchase price, shipping and PayPay fees it better be something darn special

noglider 

You mean Bikesmith, not Wheelsmith, right?

Amesja

Oops. My brain does that sometimes

I've been doing wheels all day today so iI think I have wheels on the brain.

noglider 

What are you, a mechanic at a 3-speed specialty shop?

Amesja

It's beginning to look that way. I'm waiting on the spoke dude to get back to me and depending on what he says I'm either going to pulling the trigger on a $185 order from Niagara or a $275 one... I've got 1 bike on the stand and 2 more lined up behind it

Yup, looks like a 3-speed shop!



These look even better in person than the picture shows.

reptilezs

why use the inner part to press the cotter out? have you tried using the outer part to press it out? is the outer part not strong enough?

Grand Bois

We used a VAR press at the Peugeot/Raleigh/Columbia shop where I worked. I like my Bikesmith Design press better.

https://sheldonbrown.com/var/pages/var0012.html

Amesja

I tried using just the outer part the way it came without modifying it but because it had a hole in it it put all the pressure on the outside of the threads and messed them up. The inner part has a nice cup on the end so that when it is inverted with my mod an the hole enlarged so it fit into the outer part backwards it does not damage the threads of the cotter or leave any mark or mar on the big end of the cotter when pressing it it -plus it is self-centering.

I guess it is possible to use the inner part but not tighten the inner bolt to push on it. One could just turn the outer bolt. The thing with this is that the thread pitch of the inner bolt is about 1.5 or more the thread pitch. This means that the leverage ratio of turning the inner bolt is 1.5 or greater over the outer bolt.

If the pin breaks it would be possible to keep using it but the inner bolt wouldn't be able to press on it any more. Then one would have to test out the theory of how well the pressed worked only turning the outer bolt. Perhaps just turning the outer bolt is a good idea when tightening up cotters as the force keeps getting greater as the pin gets further and further pushed out.

I suggest that when one uses this press mod to tighten a cotter one keep the pin very close to the outer bolt and not let it extend more than an 1/8" or 3/16" out. I was messing around pressing a cotter in the other day on my press and let it get over 1/4" inch out and I could see that the tool wasn't perfectly perpendicular to the cotter due to the profile/shape of the particular brand of cottered crank. I saw it wasn't straight but I was too rammy and in a hurry to back it off and move up the outer bolt and instead figured one more click on my ratchet wrench would be enough and not hurt anything. I snapped a pin and now I don't have a spare.

Maybe just using the outer bolt is a good idea when pressing in the cotter. When pressing it out the pin does not extend at all if you start tight until the pin pops free and at that point it takes no force at all to move it so there is no danger of snapping the pin as it gets further out.

larwyn

I made myself a cotter press a few days ago after bending the C-clamp which had successfully removed the first cotter. It's an ugly welded up fabrication rather than the nice clean machined item it "imitates" but it it did remove the stubborn cotter that damaged a very old C-clamp and pressed them both back in with no problem. This allowed me to reuse the the "R" nuts on my '72 Raleigh. I would have made the mods to the HF tool but I needed something "now" so I scrounged around my shop for a bit of scrap material, fired up the MIG welder, and in just a few minutes I had a cotter press, ugly though it may be. It was still warm from the welding when I pressed out that second cotter and cost me $0.00.......

Amesja

Looks nice! A little bit of paint and it'll look professional

I made a chainring bolt wrench out of one of the extra pieces from this chain tool by drilling out the middle bit a little bit and cutting out two prongs on the radius of the cup and filing all the excess out of the way. Took me about 10 minutes of futzing around with a drill, hacksaw, and a file. Worked a treat. I've got a new park CNW-2 on order but I needed one RIGHT THEN. I also needed single-speed chainring bolts after turning a triple into a single for my IGH so I cut some washers up to use as shims. They'll work until the new single-speed bolts come with the CNW-2. Making your own tools is fun!

randyjawa 

I know I have shown this before but it is so easy to make if one has access to a welding machine...

Amesja

Why not use a hex-head? Easier to put an open-end wrench on? A 3/8"-drive hex socket makes the job really easy...

randyjawa 

Because that is a grade 8 bolt (set screw to be precise) with a recessed end that cups the cotter pin perfectly, helping to keep the bolt centered on the pin. Works great. Besides, I use a 6" adjustable and it works just great also. And, for what it is worth, you can get the same bolt in Allen wrench design but I prefer the square head.

larwyn

Randy, that is the one that I remembered seeing when the need for one struck me. I copied your design as closely as my memory of it and my available scrap pile would allow. Thanks for the inspiration.

The grade 5 half inch hex bolt was the best I could do with what I could find in my shop at the time. It is slightly cupped on the end and, as you stated, that did help keep everything all lined up. I just use the same 3/4" wrench for the press that I use to lock the rotation on my work stand (it's always handy). My press did come out a little heavy though as the bar stock that I used is 1 1/4" x 3/4".....

marley mission

gentlemen - lets see some of these homemade presses on ebay already - nice work
though i have the bikesmith press already - you are making me want to investigate making my own press as well

tell me - for someone with no welding experience - is this a good place to cut your teeth or no?

noglider 

I still haven't made or bought anything. I had an old English 3-speed whose cotters were both inserted in the same direction. Some idiot was the last to work on the bike, clearly. So I had to knock one out and put it back in. I had someone helping me, so I had him hold the bike way up high and rest the crank on my bench vise. The vise was open enough to let the cotter through. I used a ball peen hammer. We used the same procedure for putting the cotter back in. It seems to have gone well.

robertob

I use the bench vise too, works great if you're dealing with just a frameset. Now a fully assembled bike might be tough!

rhm

I weakened and ordered one. On sale for $9.99 at the moment.

I have the BikeSmith tool, but I also have two cranks that it doesn't fit; not enough clearance. The Harbor Freight one, when it comes, has a date with my bench grinder!

Amesja

I will be looking forward to a report on how the two tools compare side-by-side.

randomgear

Re-title this thread!
It's on sale for $9.99 - I just ordered mine!

Amesja

How much is shipping? I'm an "Inside Track" member and could pick one up but the nearest store is a good 35-40 minute drive from me and is a couple of tolls too. Cost for gas and tolls would be way more than the savings or even the cost of the tool at the regular price.

Captain Blight

I never use a press any more. What I do is to remove the acorn nuts almost all the way, leaving them a thread or two proud of the end of the pin (Why? Bear with me.). Next I pick up the propane torch and heat the crankarm up a bit, not screamin hot but enough so that a wet finger sizzles briskly. Call it 250-275* F.

Then I drizzle some PB Blaster into the cotter recesses and walk away for a half hour. As the crankarm cools, capillarity pulls the penetrating oil deeper into the offending area (or at least I think it does; it certainly makes a kind of sense). Anyway, when I get back around to it, one light rap from a hammer usually drops the pin right on out. The nut is left on the pin threads to protect them, as it is essentially impossible to get decent-quality cotter pins any more. It also helps spread the load along the threaded shaft, and gives me a bigger target for the hammer.

This works very well. In the probably 65-70 bikes I've treated this way, I've had to go through the heat/cool cycle more than once only three times, and they all responded to a second treatment. I suppose that I probably should talk the shop manager into buying Stonich's tool-- hell, one of our mechanics is buying his old lathe-- but this works so well and costs so little that it hardly seems worth it.

I really like the original post, and the philosophy therein: Take something that works well, and modify it for a completely different purpose where it will work superbly. There isn't enough of that in the world today; kudos to you, sir!

Amesja

Seems like a lot of work when the time it takes for me to take the press out of my toolbox and have it put back into the toolbox after I have both cranks out is 4 minutes flat for using it. The only thing that slows me down is the 30 seconds it takes to fit the press over the cotter and crank it down. Plus pressing them back in works so much better as they don't get loose and i don't have to worry about tightening them again after a few miles.

FFFFFFPT! Done -next.

I used to be a big supporter of the hammer method but once I got a press I realized how stupid I was being. For every job there is an easy way and a hard way. The press is the easy way. The right tool for the job makes the job a breeze while hitting at things with a hammer and using a torch seems a bit Flintstone Wrench to me.