Pair of Die Blocks - how to use them

[minilathe22]

Hello All,

I want to make some big chunky threads in wood, so I have bought a tap which is 1 1/2" 6 tpi for only £12. I chose a Whitworth thread, so the threads are nice and rounded, which I think will help stop the wood from splitting, and maybe look nicer. I have found that normal round or hexagonal dies in this thread are very expensive, at least £70 for a used one.

I managed to purchase these "adjustable die blocks" for only £10, but they do not come with anything to hold them in place. What would commonly be used to hold these for cutting a thread? I have search the net for "die block holders" but didn't see anything that looked like it would help.

 

[Trevanion]

Those are very old school! You need a particularly large-sized monster of a square die stock for them, You see them all the time on eBay but I'm not sure if I've seen one that will do 1 1/2. It also looks like they've got bevels on the sides which might suggest a particular fitment into a certain style of holder as well. I'm sorry I can't tell you more as I don't really know too much about them, perhaps the more hardcore engineering members of the forum (retired engineers) could point you in the right direction?

Like these:

 

[minilathe22]

Thank you Trevanion, that looks like the thing I need.

I wonder as I am cutting threads in wood, if I can get away with a wooden version of the ones you linked to. As you say, I would have to seek out one that fits the chamfered edges of the ones I have, which I guess would take a while and may not be cheap!

Thanks again,

 

[CHJ]

...
I wonder as I am cutting threads in wood, if I can get away with a wooden version...,

I would say you stand a very good chance of a wooden Die Stock being adequate for your needs as long as you use a suitable hard wood such as Beech, Oak or similar for the body.
If you accommodate the Vee edge along one side it will help prevent the dies moving sideways, you will need to insert a packer along the other side of the frame aperture to allow room for you to insert the dies, or fit the plain side member after the dies are located.

 

[minilathe22]

Thanks. Yes I will need to come up with a clamp of some design, to put them in and then close it. I assume I can do light cuts if I put a not of spacer between them on the first pass. Then remove the spacer and rerun it. This would help reduce required torque.

 

[Dalboy]

I have a holder and a number of sets of the thread blocks will take a photo in the morning

 

[minilathe22]

I would be interested Dalboy if you have one that fits! I have not received them yet but the description says

1 1/4" wide x 1.85" long.

I don't know what the third dimension is.

 

[Dalboy]

Here are the photos of my set up. As you can see 4 sets of dies a locking ring which also holds the guides in place

 

[minilathe22]

Thanks Dalboy. I had assumed the holder would be square. I have seen one for sale but not sure it has a big enough space for 1 1/2". I will keep looking out for one though.