Modern Bond Mold

[bullet maker 57]

I have a B 452-650 mold with a broken sprue plate screw ( broken off in the mold). Is there anyone that fixes these molds? It needs to have the broken piece removed and a new screw made or purchased. This mold drops really nice boolits for the 45acp. I would really like to get it repaired. Any help will be greatly appreciated.

Thanks
Pete

[cbrick]

Here ya go . . .

Hollow Point Bullet Mold

Rick

[bullet maker 57]

Thanks cbrick.

[bretNorCal]

If you want to do this yourself, there are reverse drillbits that can remove broken bolts. https://www.youtube.com/watch?v=FYvaPbX1sT4

Once you have it removed you may or may not need to rethread, depending if there is damage to the threads. There are rethreading taps available for this. If the threads are too far gone you will have to drill a new hole and tap the next size larger.

[bullet maker 57]

I have the left handed drill bits. I may be able to get the broken part out, but I will still need a new screw. I would prefer to have someone remove the broken screw and either make or provide a new screw. This screw keeps the sprue plate in place.
Thanks
Pete

[bretNorCal]

You would have to measure the bolt and order one, or better pick one up at the local hardware store. Or drill and tap for something known. There are tools to measure such things although in a pinch you can use calipers and look for something that is close. 5 main parameters

The head of the bolt (without an image I cant say). If its recessed this is more important, I cant imagine why it would be so any hex head should work.
The length. It needs to be long enough to bite into the mould but not so long it cant hold the sprue plate in place.
The diameter. This will normally be a standard of which there are many but often some normal number in either metric or standard. Calipers should give you enough info to know.
The thread pitch. How many threads per inch. This is often one of only a few choices. You can just count them.
Full thread or not. There may be a spot on the bolt that is not threaded, which is likely the case where the sprue plate turns. This dimension needs to be known so you will need both parts of the bolt.


Now it could be a totally custom bolt but that is unlikely. It has been cheaper to buy off the shelf bolts for a long long time. If you have the bolt head can you post a pic with a ruler in frame and next to the bolt with good lighting (avoid shadows on the bolt itself) and in focus of the side, top and broken/threads side? Avoid using a flash and if you use a ruler that is reflective try to avoid lighting angles that cause glare. I will see if I can figure out what bolt it is and where you can order one Worst case you posted pics, best case you can get a replacement bolt. Using calipers would be just as good. Post some dimensions and I can see if I can find a replacement. A pic of the bolt head and side would helpful though.

[paul h]

Any decent job shop machine shop or gunsmith should be able to handle removing the broken screw. Of course the question is why did the screw break, and is the remaining screw rusted in place? If you have a drill press, it's a pretty simple job to center punch the screw, drill a small hole and drive in an easy out. If that doesn't work, you can carefully drill out the screw until you are at the root dia, and then remove the remaining bits of bolt with a dental pick. Run in a bottoming tap to clean up the threads and replace the bolt.

The key is that this work be performed carefully, as the sprue pivot bolt needs to be perpendicular to the face of the mold. Getting it cockeyed will ruin the usefullness of the mold and require some more extensive repairs such as drilling out the hole to sink a plug and then drilling and tapping a completely new thread for the pivot bolt.

[bretNorCal]

The bolt is a slotted pan head bolt. These are common enough that ordering a replacement should not be terribly difficult, unless they used some wonky custom threading. I think it unlikely that they did because standardized bolt threading had been around for over 60 years when they made their first molds and its cheaper to buy standard bolts than custom thread something.

I just dont know the dimensions. The head appears to be about 1/3" on the molds that I have seen which *implies* that the shaft is about a #8 cause that is what a common head to shaft ratio is. As there were no measurements provided on the random google image searches I did nor much of a frame of reference or good angles for the dimensions I did know this is just a guess, and a poor one at that.

[Thin Man]

I pulled and measured the sprue plate screw from one of my Modern Bond molds and found the following:

Head diameter is .303" and length is .170"

There is an UN-threaded section adjacent to the head, diameter is .188" and length is .150".

The threaded shaft of the screw measures 10-24 pitch. This threaded section of my screw had been shortened before I got the mold, and (Oooops) I did not measure the depth of the screw cavity in the mold before putting it back into storage but suspect a screw with a total length of 1/2 inch should fill the cavity nicely and may even require being shortened. Hope this helps.

Thin Man

[Lively Boy]

the sprue plate stop screw is the same as the pivot screw if that helps...i have the same one. and it does shoot well in 45acp