Removing pin from old deck block?

[BAD ORCA]

I have a few old Schaefer deck blocks with badly worn sheaves. Two of the blocks have a tapered base that is custom drilled and fit to a raised mounting spot on the deck. I would love to be able to re-use these old block instead of having to fill and re-drill new mounting holes in the deck.

I got a quote from Zephyr to replace the ssheaves that was reasonable, about the cost of a new block, but being the handy DIY guy that I am with a full fabrication shop at my disposal, I figured i'd take a crack at fixing them. If it goes terribly sideways I can always send them off to Zephyr for resuscitation.

Anyways, see pics attached. The blocks have pins that are mushroomed on the top. The bottom/back i cant tell if its press fit or screwed in and then the top/outer area is flattened like a rivet.

Anyone have any idea and know how to remove these pins? Does putting new pins in require a special press machine or is there some simple DIY way to install new pins and remove the old ones?

 

[Stu Jackson]

Call Garhuaer with your plate and hole dimensions They'll make up new assemblies for you. Those are rivets, not pins. This question about these blocks has been asked and answered repeatedly over the years.

 

[BigEasy]

I have a few old Schaefer deck blocks with badly worn sheaves. The blocks have pins that are mushroomed on the top. The bottom/back i cant tell if its press fit or screwed in and then the top/outer area is flattened like a rivet.
Anyone have any idea and know how to remove these pins? Does putting new pins in require a special press machine or is there some simple DIY way to install new pins and remove the old ones?

The blocks typically have stainless steel axles/pins that are retained on the outside block surface/cheeks. The axles are similar to a clevis pin. One end of the shaft is deformed into the shape of a low profile head and the other end is deformed & rolled onto the surface of the cheek to retain the axle & sheave within the block assembly. Takes specialized machinery to create that kind of deformation in stainless steel. (See attached photos of one of my blocks)
I am presently investigating rebuilding several 60mm blocks (8) for in/outhaul lines for my RF mainsail & asym spinnaker as well as four 28mm toe rail mounted blocks for my roller furled genoa line fairleads. New ones would cost nearly a boat buck. So, I plan to rebuild them, experimenting with one of each type of block to determine if the outcome is satisfactory. I have read that there are three methods to remove the axles; (1) drill rolled end of pin with a regular drill, being careful to avoid damaging the hole in the cheek. (2) Use an angle grinder on rolled end of pin, being careful not to abrade cheek surface. (3) use an end mill to carefully removed the rolled edges without damaging the cheek surface or hole. I have a 5/16" end mill on order now that I will use in a drill press. Once the rolled edges of the axle are removed, knock out the axle using a drift punch or press it out using a bench vise. Don't know yet whether I will use bronze bushing within the sheave; depends on what I find when I disassemble the blocks & how the new sheave & thru bolt fits.
I plan to use a 316 stainless bolt as a new axle with the smooth unthreaded portion within the new Delrin sheave, with sufficient threads extending through the outside cheek surface to engage a nyloc nut to retain the block components. On some of the deck mounted blocks, I understand that there may be sufficient space to grind the bolt head to fit beneath the bock & deck to capture the bolt.
I have lots of time available & most of the tools and equipment on hand, so I am going to give it a go. Estimated $ savings is 2/3 that of new blocks Schaefer Delrin sheaves are readily available ranging from $12- 20 (depending on size) & thru bolts for under $2.

 

[BAD ORCA]

The blocks typically have stainless steel axles/pins that are retained on the outside block surface/cheeks. The axles are similar to a clevis pin. One end of the shaft is deformed into the shape of a low profile head and the other end is deformed & rolled onto the surface of the cheek to retain the axle & sheave within the block assembly. Takes specialized machinery to create that kind of deformation in stainless steel. (See attached photos of one of my blocks)
I am presently investigating rebuilding several 60mm blocks (8) for in/outhaul lines for my RF mainsail & asym spinnaker as well as four 28mm toe rail mounted blocks for my roller furled genoa line fairleads. New ones would cost nearly a boat buck. So, I plan to rebuild them, experimenting with one of each type of block to determine if the outcome is satisfactory. I have read that there are three methods to remove the axles; (1) drill rolled end of pin with a regular drill, being careful to avoid damaging the hole in the cheek. (2) Use an angle grinder on rolled end of pin, being careful not to abrade cheek surface. (3) use an end mill to carefully removed the rolled edges without damaging the cheek surface or hole. I have a 5/16" end mill on order now that I will use in a drill press. Once the rolled edges of the axle are removed, knock out the axle using a drift punch or press it out using a bench vise. Don't know yet whether I will use bronze bushing within the sheave; depends on what I find when I disassemble the blocks & how the new sheave & thru bolt fits.
I plan to use a 316 stainless bolt as a new axle with the smooth unthreaded portion within the new Delrin sheave, with sufficient threads extending through the outside cheek surface to engage a nyloc nut to retain the block components. On some of the deck mounted blocks, I understand that there may be sufficient space to grind the bolt head to fit beneath the bock & deck to capture the bolt.
I have lots of time available & most of the tools and equipment on hand, so I am going to give it a go. Estimated $ savings is 2/3 that of new blocks View attachment 231039View attachment 231041 Schaefer Delrin sheaves are readily available ranging from $12- 20 (depending on size) & thru bolts for under $2.

Hey thanks BigEasy. Yeah my biggest question was that pin and what they did on the backside. If it was threaded I didnt want to risk cutting off the outside part and not be able to unthread it. I think i'm going to attempt to drill out the top side and see. Sounds like its just press fit as you described which would be great.

I was thinking of using these as replacement center pins. They have a 1/4/20 fastener and a 5/16 barrel. I'm thinking they should be plenty strong for reefing lines.

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[BigEasy]

I was thinking of using these as replacement center pins. They have a 1/4/20 fastener and a 5/16 barrel. I'm thinking they should be plenty strong for reefing lines

Yes! I do believe that would be acceptable for your application.
My end mill just arrived from Amazon, so I can begin the dissection of the bock in the picture.

 

[Deparlocean]

For drilling stainless steel like the pivot pin in your blocks, use COBALT drills as these ones stay sharp longer than any other ones. You MUST drill at slow speed to keep the drill from overheating and wearing fast. Your drill is cutting good if you see a string of steel coming out of the drilling. If not you need to sharpen the drill.

 

[BAD ORCA]

Yes! I do believe that would be acceptable for your application.
My end mill just arrived from Amazon, so I can begin the dissection of the bock in the picture.

I just hit it with an angle grinder this morning and the center pin came out pretty easy. I tried drilling but got a little off center and botched the drilling. Angle grinder was a bit messy but worked well. Ill have to do some sanding and polishing to get the clamping arm back up to snuff. The standup blocks might be a little tougher though. The rivet is crushed on both sides.

 

[BAD ORCA]

Turns out 5/16" was the magic drill bit on stand up blocks. Centered in the dimple of rivet on drill press. Drilled down .10" or so and cap popped off nicely. Hammered pin out cleanly no damage.