northsea

Making weights with plaster molds????

25 posts in this topic

Hi all, how goes?

Not sure if I am in the right section for this question but here goes. :)

I have just discovered Buzz-bombs and am not able to get hold of any in the UK and wondered if anyone had a go at making molds made of plaster for lead?

I'm pretty sure this can be done although the plaster will not last that long but perhaps long enought to make a few. :yay:

I have made a few plaster molds so have some experience and I have also poured melted lead but never together. :nono:

Not sure whether I need to seal the plaster before pouring lead etc.

Anyone have any experience in this field?

Absolutely any input very much appreciated. :yes:

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The materials available for home constructed, short life molds are: Hi temp RTV, PoP, Durhams water putty and Bondo.

PoP and Durhams, the consensus of opinion seems to be that they are only good for about 30 pours and you have to take care to make sure the molds are completely cured, as they contain water. At least a week air drying, couple of days in a warm airing cupboard or behind the fridge against the heat exchanger. Could not find any information on sealing for lead.

Hi temp RTV, room temperature vulcanising rubber, much more expensive, but should give more casts as it is flexible and thus less wear on the mold cavity. A few members have mentioned it in the past.

Bondo. This is a polyester resin based filler. It is a thick paste usually supplied with a hardener in a tube. It is used for automotive body repairs, sometimes impregnated with glass fibres. It can be mixed with polyester resin (fibreglass resin), this will thin it out enough to enable pouring. Not sure of the ratio, about 70:30 filler/resin, add more resin if too thick to pour. Use the hardener provided with the resin. This will not require a sealer, but does tend to warp under heat, so allow plenty of time between pours and make the molds thick, to minimise the warp. This mold should be good for 100+ casts.

You can search the individual items. Here are a few links to get you started:

TU reference http://www.tackleunderground.com/forum/wire-baits/14941-how-make-spinnerbait-mold.html

This leads to Triton Mike's tutorial http://www.wmi.org/bassfish/bassboard/fishing_tactics/message.html?message_id=131571

Yankee Jigger made a PoP mold, but no information or feed back. Could be worth a PM. http://www.tackleunderground.com/forum/wire-baits/14941-how-make-spinnerbait-mold.html

Likewise, PAVABill did something similar, still no information or feedback, again a PM might gey you some information, http://www.tackleunderground.com/forum/wire-baits/14137-spinnerbait-heads.html

Here is another discussion close to the subject, http://www.tackleunderground.com/forum/wire-baits/12331-custom-mold.html This refers to another tutorial by Senkosam, although intended for plastics, still good information, http://www.tackleunderground.com/forum/soft-plastics-how/5393-kb-mold-making-1-2-3-4-5-6-7-etc.html

Dave

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As Dave said; be absolutly sure that your POP molds are "bone" dry. If not you could be off to the ER for repairs.:pissed::censored:

What I did was apply several coats of oil to the cavities and allow it to soak in. You may have to re-apply the oil after a couple of pours.

Warning:- it will get smokey, so do it in a garage with door open.

Use motor oil as it will take the heat better than kitchen oil.

Let us kow how you make out.

www.novalures.com

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Many thanks indeed guys for those replies.

I'll see how I get on with it and let you know if I decide to give it a go. :yes:

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Hi all, how goes?

Not sure if I am in the right section for this question but here goes. :)

I have just discovered Buzz-bombs and am not able to get hold of any in the UK and wondered if anyone had a go at making molds made of plaster for lead?

I'm pretty sure this can be done although the plaster will not last that long but perhaps long enought to make a few. :yay:

I have made a few plaster molds so have some experience and I have also poured melted lead but never together. :nono:

Not sure whether I need to seal the plaster before pouring lead etc.

Anyone have any experience in this field?

Absolutely any input very much appreciated. :yes:

Is a buzz bomb the same as a buzz bait? If so, you can get a mold from Do-It molds to pour them with, JIM

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You don't need to drill a hole through the lead. Just install a steel rod in one side of the 2 piece mold. Make sure the rod is secured with a 90 degee bend and anchored in the POP with epoxy. After the lead cools it should pull right off the rod forming a nice "smooth" hole. Drilling will leave burrs which can cut your line.

www.novalures.com

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That is a great idea! Thank you nova! :yay:

I'm just rying to get my head around the best way of doing this.

Should I Get myself a steel rod that fits through the original "weight" then bend one end as you suggest and keep this rod in while making the plaster mold?

Crumbs, no I'm not sure about this? :?

Do I need to attach the rod to the plaster mold or could I simply lay the rod in the cavity if I do the mold side on?

Either way am I better making the pouring cavity somewhere away from the rod?

Man I'm so sorry about this aspect of things. I have no clue.:nono:

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That is a great idea! Thank you nova! :yay:

I'm just rying to get my head around the best way of doing this.

Should I Get myself a steel rod that fits through the original "weight" then bend one end as you suggest and keep this rod in while making the plaster mold?

Crumbs, no I'm not sure about this? :?

Do I need to attach the rod to the plaster mold or could I simply lay the rod in the cavity if I do the mold side on?

Either way am I better making the pouring cavity somewhere away from the rod?

Man I'm so sorry about this aspect of things. I have no clue.:nono:

It may be easier to place the rod in the mold from the bottom and pull it out just after you pour the lead. Make sure you put a small wood handle on the rod or you will burn your fingers.

Just make a groove in the mold so that the rod passes from the bottom to outside the top of the mold; and make sure it is dead center or the balance of your lure will be off.

www.novalures.com

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Ah ok that makes sense to me. ;)

So the only other thing I'm not sure about is where to put the pouring funnel?

Should this be where I already have a hole for the rod or somewhere else?

Also do I need to make a vent hole or will it be ok as long as I make the pouring chamber/hole big enough?

Again, many,many thanks indeed for your support guys. :yay:

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@ northsea

These lures are looking quite similar to "Tasmanian Devils" , but I guess , that they are way heavier , since the "Devils" only have a lead tubing insert , whereas wings and body are of transparent plastic .

The German mail order shop HAKUMA ihr Spezialist für Köder, Kunstköder, Meeresangeln, Raubfisch angeln, Pilker, Wobbler, Fischen, Bleiguss, Formen, Ruten, Rollen, Dorsch angeln, Leng angeln in Norwegen, Dänemark, Hitra sells a system based on silicone sheets , that are supposed to be used to duplicate lead lures to make clones of these .

In brief the original lure is clamped between the two silicone plates in a special frame and then placed in boiling water to cure the mold , said to be good for many casts , depending on size and weight of lures .

Haven't used it before , just wanted to mention this possibility .

On their start page go to "shop" , after on the left bar click on "Bleigussformen und Zubehör" and browse through , you should find pics of it there .

Sorry , no English site version available !

greetz , diemai

Edited by diemai
text addition

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Mold vent

The first consideration for pour hole location is to achieve a complete pour. A close second is clean up of the sprue.

If the cavity is vertical and the pour hole positioned at or close to the top, the escaping air is going to be affected by the rod insert and the narrow cavity. This is going to increase bubble contact with surfaces and increase the chance of the bubble sticking or being trapped. Also, the sprue will be in an awkward place for clean up.

My suggestion is to orient the cavity horizontal, with the pour hole at the highest point, in the middle of the back. But because the top surface of the cavity will be approaching horizontal, there is still a chance of the bubble being trapped and unable to get around the corner to exit through the pour hole.

To solve the problem of this potential bubble trap, I would include a small vent (vent 1), exiting to the outer edge of the mold, both sides of the pour hole.

A potential for a bubble exists at the junction of the rod and ends of the body. Additional vents (vent 2) can be added to solve these problems.

I suggest you make the mold without vents and cut the vents only if required. The vents should be very small diameter where they intersect the cavity, maybe just a score with a sharp knife is sufficient, otherwise the lead will pour out. Once the vent is clear of the cavity, it can be widened, this makes keeping the vent clear much easier. The vents only need to be cut on one half of the mold.

This is only my opinion, I am not an expert but still fairly new to molds. If anyone disagrees, or has other ideas, I would like to read them.

Dave

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Good diagram Dave.

This may not work as the bait in question has ribs on it and the sprue will take too much room causing a deformation of the ribs.

I suggest that you make the pouring hole on one end and pass the rod from the bottom to the top all the way out of the mold so that the rod does not get covered by the lead in the pouring hole, as in Dave's diagram.

www.novalures.com

Edited by nova

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Thank you very much guys for taking the time to respond.

I've managed to find a couple of photos of a mold that may work.

As you can see on the attachment I have drawn up 2 simple ideas that I think could work.

Nova are you suggesting I go for the B idea with the pouring hole directly above the rod?

I thought that if I copied the molds in the photos Diagram A

The rod hole may allow for air to escape as I fill it with lead?

Plans.jpg

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3999_thumb.attach

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B would not require a vent. A would require a vent at the highest point, to release the innevitable trapped bubble. I think B would be much easier to manage the rod, being fixed at both ends.

Dave

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I like the direct pour for 2 reasons in this case. The ribs won't get deformed and sometimes on an angle-pour you can get voids at the very top from time to time.

www.novalures.com

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Ok, thanks very much guys. :)

So If I go for B how will I secure the rod on the pouring end?

Also do you think I will need to turn the rod while pouring somehow or should the rod come out noi problem after pouring?

The thing that attracted me to diagram A is the fact that the rod will be secure at either end but I understand your point about the advantage of Diagram B. Obvioulsy if I am going to pour direct I need space around the rod to let the lead through. :huh:

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Just dip the rod in oil before each pour and it won't stick. Pull the rod out as soon as the lead sets which will be by the time you put down the pouring ladle.

www.novalures.com

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I would add additional mold on the bottom of the mold to better anchor the rod in place... That should keep the rod in the center a little better.:twocents:

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Shouldn't this post be in the wire bait section, the place were the real men post :lol:!!

I've done a bit of R&D (rippoff and duplicate) of a related lure, the Zzinger.

This mold was my first Bondo mold and was made in 1988. It's 20 years old and has poured over 50 castings. (Ignore the 2 holes that I drilled in the back of the casting, it was a balancing experiment)

IMG_1417-1.jpg

Luckily I saved a private message about how I make my Bondo molds. I hate re-typing stuff :angry:

First you need a pattern, or master that you're going to copy. It can be

made from metal, wood, plastic, etc., but it must be fairly strong and

rigid, have a smooth surface, and have no undercuts, so that it and the lead

casting will come out of the mold. You could also copy an existing

lure as well.

Here

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Northsea,

The mold-gating design provided by Vodkaman is unquestionably the best one for your purposes. The only alteration would be that the vents at the #2 location are unnecessary, as the rod pass-through holes provide enough venting at that area. With that one sketch, Vodkaman has given you most of what you need to know. Glaucus's mold follows this pattern, and his advice is also instructive here.

I recently made a Bondo mold (3oz cavity) similar to your proposed buzzbomb design. After quite literally several hundred casts, it's as good as new. I used wheel-weight (hard) lead with no problems.

Some concens that will confront you:

Do not apply oil or any liquid to the cavity, or to the line-hole rod. Oil will cause bubbles in the casting and is a potential fire and splatter-hazard.

Use hard stainless wire of at least 0.050" diam for the rod. Replace whatever line-hole wire you used during mold construction with the 0.050" (or larger) rod. Carefully shave or drill out the rod pass-through holes to accomodate the 0.050" rod.

As the lead cools, expect the casting to grip the wire very tightly. The rod must be smoked or dusted with either mica powder or moly powder before each pour. Removing the fragile casting from the wire or rod may be-- by far-- your biggest challenge. Removing the wire before opening the mold may be the only way to avoid damaging the casting. Do not ignore this consideration.

A sprue located on one of the buzzbomb 'wing' provides the best placement, and be sure to make each mold half no less than 1" thick.

Bondo is an insulating material with poor thermal conductivity. This means that only a small sprue is necesary. You should get perfect results from a sprue that tapers to an 1/8" or less. I used 1/8" with no difficulties, and probably could have gone as small as 1/16"-- no exaggeration.

Hope this helps, good luck.

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Thanks very much guys for the added info. Nuch appreciated indeed! :yay:

Glaucus how do these zzinger lures work in the water compared to Buzz-bombs? They look good and you mold and info attached looks fantastic!

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