Lee needs to be fixed

[soless]

Hello every one. Long time lurker. But I have learned quite a bit from everyone here. Here is my story. I was gifted a non working mold. The mold was modified. Or in the process at least. Someone tried to drill and tap a hole on a side of the mold that leads to the sprue plate screw. The tap has been broken off and is stuck and has been cut flush to the mold block. I tried to cut a slot in the tap and unscrew it with a screw driver but that thing is stuck in there pretty good. I was thinking I could mount the sprue plate to be operated in the opposite direction. I will have to modify the sprue plate a little to make it work. Is this a good idea? If so, can anybody clue me in on what the thread pitch is for the sprue plate screw? Thanks in advance.

[Wally]

This would be a difficult fix... looks like they tried to drill & tap a side hole to lock the sprue plate screw and didn't lube the tap enough it siezed up and it broke off. If I were you I'd contact Lee..they might replace the mold for 1/2 the list price of a new one...

[Harter66]

Having only taken 1 LEE mould apart I believe they are 8x32s w/ a collar bushing. I'd take the dimensions for center of the damaged hole and set it up on the opposite corner and w/a new drill and new tap move the hole. Lisa new based on aircraft expirence,aluminum and stainless tools should be used for just that often tools used elsewhere then on AL or stainless will gall or sluff especially little bitty threads. Then turn the mould around on the handles.

There is another recent post where a fellow had a similar situation and a pronged tap extractor was recommended as well as a punch to break up the tap, that may have been a 1/4 inch tap. Some heat applied to the blocks might allow enough slack to back out the tap also.

[theperfessor]

Good advice there. Lee uses what I think is 6061 aluminum alloy, which is kind of soft. Sharp tools are absolutely necessary to prevent tearing, especially when tapping. I use a commercial aluminum tapping fluid that I buy in bulk, but BullPlate lube will work just fine. And if you have a Lee mold you ought to be using BullPlate already.

I believe the pivot screw has an interference fit, but I don't know whether the screw is oversize or the original tapped hole is undersized. I think you'll probably have to drill and tap for a setscrew when you do this mod.

[deltaenterprizes]

Soak the mold corner in a solution of alum and water, the alum will eat the tap and not the aluminum. An old machinist trick.

[Chicken Thief]

I just cut up an old banger that had a fatal wound.
As you can see the screw hole is not threaded and the screw has some sort of penta scarring to make it self-tapping/locking.

My experience is that for the time being it stays put the mould works 100% but you have to lubricate or it (the screw) will bind sufficiantly to slightly work loose. When so and tightened things go from bad to worse, and the set screw is a must.

http://i295.photobucket.com/albums/mm153/Chickenthief/Skydning/R0010456.jpg
http://i295.photobucket.com/albums/mm153/Chickenthief/Skydning/R0010457.jpg
http://i295.photobucket.com/albums/mm153/Chickenthief/Skydning/R0010458.jpg

[Jal5]

I would try to soak it in a penetrating oil for 24 hrs. then use a tap extractor to get that tap piece out. then you could see about whether you want to do another tap and die for the set screw or not.

Joe

[theperfessor]

Thanks for the photos!

[kenjuudo]

Lee uses a 10-32 self tapping screw. I've machined the head off, drilled the screw body to below the top of the mold. Then removed the pins and reversed the blocks in the handles. This let me drill and tap another hole for the sprue plate and carry on. Alot of work for a cheap mold, but sometimes you just do things because you can.

jim

[mooman76]

I'm not 100% sure but I think you can reverse the sprue to the other end like you said and then remove the mould and turn it around 180 degrees so it is right again.

[bhn22]

If it's a 2 cavity mould, toss it & buy another. This is a lot of effort for a $20.00 mould. A 6 cavity mould might be worth a little effort. If you want to remove the handle pins from a 2 cavity mould, a Dremel with a burr tool should remove the crimped aluminum at the handle pins.

[MT Gianni]

Like trying to repair a bic lighter. Sometimes you just have to move on.

[quasi]

For a cutting fluid for Aluminum, I just use WD-40, it works very well. You do need sharp taps for 6061.

[JIMinPHX]

I'd take the dimensions for center of the damaged hole and set it up on the opposite corner and w/a new drill and new tap move the hole. Lisa new based on aircraft expirence,aluminum and stainless tools should be used for just that often tools used elsewhere then on AL or stainless will gall or sluff especially little bitty threads. Then turn the mould around on the handles.


I think that this is the most reliable solution. The alloy that Lee uses for a 2-cav mold seems a bit on the soft & stringy side. It roll taps better than it cut taps. I can see where someone might get into trouble with a small diameter tap in that material, especially if they didn't use good lube or if they applied a little side load to the tap. The 6-cav molds from Lee that I have messed with cut just like 6061 alloy.

My general purpose favorite method for removing broken bolts or broken taps from aluminum is to put a nut over the broken bolt/tap & then Mig weld the nut to the bolt/tap through the center hole of the nut. Mig wire doesn't stick to aluminum very easily, so this usually works well in aluminum base material. It does not work well with steel base material. As soon as the orange glow goes away, turn the broken part out with a wrench. Aluminum expands about twice as much as steel with the same change in temperature. As soon as the orange glow goes away is when you have your best clearance to work with.

If you have a lot of time on your hands, you might also try to rust the tap out. Aluminum has much better corrosion resistance than most steels do. This is a very slow process, but it does work. It works better with carbon steel taps than it does with HSS taps.

Sometimes people get lucky & just heating & cooling the block a few times in the freezer & a 200F oven is enough to loosen up the broken tap & allow you to remove it. If the tap broke going in, this is less likely to work than if the tap broke coming out.

Edit:
Alternately, you could put it up for sale cheap as a basket case on the swappin & sellin section of the board. Somebody that happens to have an EDM machine sitting in his shop, or someone with some other serious tools laying around might want to pick it up if they think they can salvage it without too much effort. To a guy with a big shop, getting a broken tap out of aluminum or reversing the blocks around is not such a difficult challenge. you probably would not get more than $10-15 shipped for it, assuming that it is a 2-cav & is otherwise complete. If it is an obsolete or popular boolit variety, you might get a little more interest.

[Mk42gunner]

If it's a 2 cavity mould, toss it & buy another. This is a lot of effort for a $20.00 mould. A 6 cavity mould might be worth a little effort. If you want to remove the handle pins from a 2 cavity mould, a Dremel with a burr tool should remove the crimped aluminum at the handle pins.

I agree with bhn22.

I like to tinker with stuff just to see if I can make something work, plus I'm cheap. However, unless the mold isn't made anymore, two cavity Lee molds are pretty much disposable once something goes seriously wrong with them.

Robert

[MtGun44]

I have fixed stuff "just because" lots of time, and this would be the only reason to do this,
unless you are as poor as I once was when I was in college. $20 and you have a new one,
but for some of us that challenge is there . . . . . . . . just sayin'

Everybody has their $ to hours spent personal ratio and it changes with time.

Bill

[bhn22]

Everybody has their $ to hours spent personal ratio and it changes with time.

Bill


Quite right