Hammerform idea

[karmat]

Okay, I'm just brand new to this so this may be a really dumb question. I have a need to make some panels to replace rust on a few old cars and I came up with an idea for a hammerform. There is a high-strength very very fine-grained concrete used for anchoring heavy machinery called Rockite. It's rated at some ungodly compression rating which I can't remember right now. What I was thinking was that if you could pour a casting of the inside of the panel in Rockite and re-inforce it with 1/4" threaded dowel, you could then use it as a hammerform for steel. Obviously it would have to be pretty thick all around, but the idea was intriguing to me. Has anyone tried anything like this? I saw the very labor-intensive, gorgeous buck and hammerform that Randy(?) Ferguson made for the Impala fenders, and that's probably the right way to do it if you're making multiple panels, but this idea was intriguing to me anyway. Perhaps I'm just trying to cheat. :) Anyone done something like this?

Thanks!
Karl

[karmat]

Okay, I'm just brand new to this so this may be a really dumb question. I have a need to make some panels to replace rust on a few old cars and I came up with an idea for a hammerform. There is a high-strength very very fine-grained concrete used for anchoring heavy machinery called Rockite. It's rated at some ungodly compression rating which I can't remember right now. What I was thinking was that if you could pour a casting of the inside of the panel in Rockite and re-inforce it with 1/4" threaded dowel, you could then use it as a hammerform for steel. Obviously it would have to be pretty thick all around, but the idea was intriguing to me. Has anyone tried anything like this? I saw the very labor-intensive, gorgeous buck and hammerform that Randy(?) Ferguson made for the Impala fenders, and that's probably the right way to do it if you're making multiple panels, but this idea was intriguing to me anyway. Perhaps I'm just trying to cheat. :) Anyone done something like this?

Thanks!
Karl

[Hemirambler]

I say go for it. I've only ever done aluminum on a glass/steel wire buck that I used as a hammerform in places - it worked fine especially for a one off.

It sounds easy enough to try - so I think if it were me I'd be mixing up a batch!!! - I've seen guys use Saran (sp?) Wrap for a release agent - I tried it on some "bondo" bucks - worked great.



Good Luck



Jacin in Ohio

[Hemirambler]

I say go for it. I've only ever done aluminum on a glass/steel wire buck that I used as a hammerform in places - it worked fine especially for a one off.

It sounds easy enough to try - so I think if it were me I'd be mixing up a batch!!! - I've seen guys use Saran (sp?) Wrap for a release agent - I tried it on some "bondo" bucks - worked great.



Good Luck



Jacin in Ohio

[Boogiemanz1]

Hi Karl, welcome to Metalmeet. I don't know if anyone has used that approach yet....you may be a pioneer! One thing you have to consider for sure is if you can get the concrete out of what yo poured it in! Randy's buck is in two pieces so it can be removed from the fender, you would have to make considerations for a 1 piece hammerform.

If you are just working on a skin, or something like wheel radius, the concrete may work.

How tough is this stuff? You may want to make a thin piece and see how many blows it takes to chip or break it.

later....jb

[Boogiemanz1]

Hi Karl, welcome to Metalmeet. I don't know if anyone has used that approach yet....you may be a pioneer! One thing you have to consider for sure is if you can get the concrete out of what yo poured it in! Randy's buck is in two pieces so it can be removed from the fender, you would have to make considerations for a 1 piece hammerform.

If you are just working on a skin, or something like wheel radius, the concrete may work.

How tough is this stuff? You may want to make a thin piece and see how many blows it takes to chip or break it.

later....jb

[karmat]

I think I'll take you up on the idea of making a test piece to try it out on. Thanks for pointing out the necessity of splitting the buck where necessary to remove it from the piece. :)

Karl

[karmat]

I think I'll take you up on the idea of making a test piece to try it out on. Thanks for pointing out the necessity of splitting the buck where necessary to remove it from the piece. :)

Karl

[Keith]

Hello Karl,

The concrete approach has been used by Cass Nawrocki. A very talented craftsman and wheelman.

In the "Ultimate sheet Metal Fabrication" book he shows some examples of his concrete hammerform.

good luck,

[Keith]

Hello Karl,

The concrete approach has been used by Cass Nawrocki. A very talented craftsman and wheelman.

In the "Ultimate sheet Metal Fabrication" book he shows some examples of his concrete hammerform.

good luck,

[Ron Naida]

There are some materials I have wanted to try for bucks and body contouring. Perhaps someone can experiment before I get a chance.

Vermiculite the large bags about the size of hardwood mulch when mixed with a half bag of 90lb portland cement is what I used in the old days for vinyl pool bottoms. This is a little tricky to get used to as in troweling but when it cures it is like a dried sponge and very light in weight. A little practice and you could shape a body buck. Good to contour but not for hammerforming.

Dura bond 30 60 or 90 sets in those time periods. Does not sand to shape well. reinforce with glass cloth or chicken wire

Plaster. Portland cement and marble dust mixed in the recommended quantities. reinforce as above. you can hang 1" square tiles on a verticle pool wall so a basic wood frame ,chicken wire for a body shape.and apply with a trowel or large bond squeeges. Sags less than fiberglass, bondo, or top coat. If it can be used to form detailed crown mouldings at ceilings by screeding it could be used just as clay for body profiling..

Thin set or any other high early masonry products. High strength early set. Means it has great adhesion and sets quickly.

These are just some of the materials that come to my mind as being a possibilty when I hear the term bondo buck.

Ron Naida

[Ron Naida]

There are some materials I have wanted to try for bucks and body contouring. Perhaps someone can experiment before I get a chance.

Vermiculite the large bags about the size of hardwood mulch when mixed with a half bag of 90lb portland cement is what I used in the old days for vinyl pool bottoms. This is a little tricky to get used to as in troweling but when it cures it is like a dried sponge and very light in weight. A little practice and you could shape a body buck. Good to contour but not for hammerforming.

Dura bond 30 60 or 90 sets in those time periods. Does not sand to shape well. reinforce with glass cloth or chicken wire

Plaster. Portland cement and marble dust mixed in the recommended quantities. reinforce as above. you can hang 1" square tiles on a verticle pool wall so a basic wood frame ,chicken wire for a body shape.and apply with a trowel or large bond squeeges. Sags less than fiberglass, bondo, or top coat. If it can be used to form detailed crown mouldings at ceilings by screeding it could be used just as clay for body profiling..

Thin set or any other high early masonry products. High strength early set. Means it has great adhesion and sets quickly.

These are just some of the materials that come to my mind as being a possibilty when I hear the term bondo buck.

Ron Naida

[hardtailjohn]

This has been done with great results in the aircraft industry before. The ones that I'm familiar with were done with a female buck, and were formed by dropping a shot bag on the aluminum for starters, then working to hammers and finishing on a wheel. It worked well and was suprisingly quick. Delmar Benjamin and Steve Wolff used that technique to form the wheel pants on Del's GeeBee replica.
The other one that I saw had a bunch of vacuum ports hooked to it and soft aluminum was sealed and fastened to the female form. Then it was thrown into a horse trough of water and an "M80" was pitched in the water. The concussion of the explosion caused the forming, and it was waaay cool to watch! The noise and mess were fantastic! I'm not sure where he came up with the idea, but it made a great start to a piece on the nose of a Grumman Goose!
John H.

[hardtailjohn]

This has been done with great results in the aircraft industry before. The ones that I'm familiar with were done with a female buck, and were formed by dropping a shot bag on the aluminum for starters, then working to hammers and finishing on a wheel. It worked well and was suprisingly quick. Delmar Benjamin and Steve Wolff used that technique to form the wheel pants on Del's GeeBee replica.
The other one that I saw had a bunch of vacuum ports hooked to it and soft aluminum was sealed and fastened to the female form. Then it was thrown into a horse trough of water and an "M80" was pitched in the water. The concussion of the explosion caused the forming, and it was waaay cool to watch! The noise and mess were fantastic! I'm not sure where he came up with the idea, but it made a great start to a piece on the nose of a Grumman Goose!
John H.

[Doug98105]

The material I'm familiar with is called Hydro-Stone. Technically it's classified by the manufacturer as plaster. Of all these type products I've run across Hydro-Stone has the highest compressive strength by a long ways. I know it's used extensively for forms in stretch forming aircraft panels of aluminum. Not sure how well it'll hold up to concentrated impacts during hammer forming, but if it won't probably no other cement type product will.

Do a search on Hydro-Stone and you'll find more info than you could ever use.

IIRC, it costs about 30 bucks for a 100 pound bag.

Mixing instructions are very specific to get the maximum strength. The proportions of mix to water and mixing time are fairly critical.

Doug

[Doug98105]

The material I'm familiar with is called Hydro-Stone. Technically it's classified by the manufacturer as plaster. Of all these type products I've run across Hydro-Stone has the highest compressive strength by a long ways. I know it's used extensively for forms in stretch forming aircraft panels of aluminum. Not sure how well it'll hold up to concentrated impacts during hammer forming, but if it won't probably no other cement type product will.

Do a search on Hydro-Stone and you'll find more info than you could ever use.

IIRC, it costs about 30 bucks for a 100 pound bag.

Mixing instructions are very specific to get the maximum strength. The proportions of mix to water and mixing time are fairly critical.

Doug

[Boogiemanz1]

I seem to remember reading about a low temp pouring metal used to make hammerforms for aircraft...was it kirksite or something like that......is it still available?

[Boogiemanz1]

I seem to remember reading about a low temp pouring metal used to make hammerforms for aircraft...was it kirksite or something like that......is it still available?

[karmat]

Well that hydro-stone sounds interesting, too. I read up on that here:

http://www.silpak.com/products/casting/hydroston.htm

The stuff I was talking about is found at:

http://www.rockite.com/

They claim that Rockite expands, so that may make it unsuitable. Maybe I'll have to come up with one of the project pieces and try both products to see what happens. Might be interesting to know. The Hydro-stone sounds cheaper, since the Rockite is pretty pricey. I'll see if I can find it locally.

Thanks for the info!

Karl

[karmat]

Well that hydro-stone sounds interesting, too. I read up on that here:

http://www.silpak.com/products/casting/hydroston.htm

The stuff I was talking about is found at:

http://www.rockite.com/

They claim that Rockite expands, so that may make it unsuitable. Maybe I'll have to come up with one of the project pieces and try both products to see what happens. Might be interesting to know. The Hydro-stone sounds cheaper, since the Rockite is pretty pricey. I'll see if I can find it locally.

Thanks for the info!

Karl

[chardy]

On reading this thread,which is good brainstorming!Concrete for forms to bend metal is a tried a true method in prototype auto panels and most likely in all metal stamping.I used to work for a company( Allied Products-since closed) here in Hillsdale.In the old days they used concrete-Hydrostone I believe;to make dies for limited run panels. the dies made good proto. panels. Allied made big dies for big auto panels,fenders,roofs,1/4 panels,etc.The concrete doesn't take a beating very well,a few parts;then scrap the die. still cheap when proofing panels. The other material mentioned was kirksite,a zinc based alloy. It has a fairly low melting temp. and will pour into any well made mold. It does have a problem,it will distort with continued hammering,one solution was to face the die face with epoxy-a metal filled epoxy. We used a heavy based epoxy,I don't remember the brand,if the company still is open? Kirksite is still available. Check salvage yards,etc. I am looking for a small amount 20 lbs or so,the price should as for scrap zinc, under a dollar a lb. Hope this helps,its is a viable idea. even the concrete could work;maybe with a filled epoxy face?

Dick Stack :)

[rkilgore29]

Hi All,

This is a very interesting thread. I have enjoyed the discussions and thought that I might add to it a bit.

I have used concrete for simple dies to press parts and have used those dies to further qualify the parts over by hammering afterwards. The shapes have been fairly simple compound curves with no sharp detail or severe reverse curves. If you have a part that you can pull a duplicate from, concrete can be a simple solution for hammerforming one or two parts.

I prefer hardwood for most shapes requiring small quantities. I have used a variety of woods and for most parts mahogany gets my vote for ease of carving and still being tough enough to get as many as 4-6 parts from aluminum, but only 1 or 2 from steel. Sharp details suffer first, tending to soften or round off. Reverse curves suffer some localized dimpling or flat spots from the amount of abuse from the constant hammering in these areas. I have used many other woods with varied success, finding the ones that carve easiest hold up the least well and the ones that hold up best are the biggest pain to carve. I prefer to do all of the finish work by hand instead of power tools. I find I have more control over the accuracy that way. Power tools make the roughing go quicker and for finish work make mistakes happen quicker.

I have also used kirksite, aluminum and steel for higher quantities or more detail. Lately I have been involved with some experimentation using machinable plastics as a possible substitute for the hardwood hammerforms. It is showing promise since it works easily like mahoganyand holds its form in a similar manner. We have a lot of it around for CNC tryout parts.

Thanks for the interesting discussion.

[Boogiemanz1]

Rick, can you post any pictures of these hammerforms with kirksite? Or any of wood or concrete? Thanks...john

[Gene_Olson]

over in the hand tool section i mentioned this for hammers,
It might also make a good facing material for hammerform dies.

Resurfaceable too.

I was actually tossing around the idea of a teardrop shaped deadblow hammer. I think working in an injection molding shop gives me crazy ideas like that.

Would it work? It would solve the "too light" issue.

Tim D.

So Tim,

as a plastics professional what do you think of this stuff?

Jett Sett it's a thermoplastic with the addition of a ceramic material.
http://www.contenti.com/products/setting_tools/510-620.html

It looks like injection mold stuff that you just heat and form.

The discussion on ArtMetal has been about shear thickening, (the aspect of a suspension of particles such as very thick cornstarch in water that causes it to flow in response to slowly applied forces but bounce if thrown)

It would seem the ceramic particles in the plastic add that sort of impact strength.

This could be a rather quick fix to just form an end on a dead blow and try it.

Gene

[rkilgore29]

Hi John,

Most of the work I have done through the years has not been recorded with pictures. I have been working in the automotive prototype business for the past 19 years and with most projects being secret so to speak, I have just plain missed a lot of opportunities for capturing parts and processes. It doesn't help that I usually don't think about pictures until the project is on its' way to the customer. :oops:

I do still have a few things around, so I'll see what pictures I can come up with.

[ralph]

Hi Rick,

Wyandotte? Prototype?

Ford? Or one of the local prototype shops. I spent 38 years at Ford in Stamping. Most of it related to die construction finance. Spent most of my time on the floor understanding the how's and why's rather than counting beans. Considered myself more a translator and salesman than a bean counter. Last 10 years or so housed at the Pilot Plant.

[rkilgore29]

Hi Ralph,

Local shops, I started out at Rousch and migrated to Batten Engineering, a part of what used to be Batten Heads. The company has been bought and sold a number of times with the most recent being Ricardo. The bulk of my experience is engine related. I have some body experience, none of it professional.

I fool around in my garage when other projects allow and am slowly working on a wheeling machine. I have a MetalAce machine at my disposal so the incentive to move quickly on the wheel is low.

I am mostly interested in art metal projects now. I have always considered a lot of the work to be functional sculpture, now I am influenced more from whimsy than function. Most of the little things I have worked on have been process exercises using minimal tools. I am constantly looking for simple or subtle techniques to exploit.

I enjoy this group because there are a lot of cool ideas being talked about and people are trying these ideas out delivering feedback. This is something that has definitely been lacking until the most recent years. Our numbers, while seemingly growing are still few in the grand scheme. This sharing is very important.

[ralph]

Rick,
You'll enjoy this metal art. Greg Koesel produced these and just ended a display at Monroe County Community College and the Ellis Library.
http://www.metalmeet.com/photopost/showgallery.php?cat=3346

Greg is an accomplished metal shaper and an avid car nut. (33 Willy's, 48 Anglia, (2) 27 T Roadster drag cars., a homebuilt Roadster pickup drag car, and a homebuilt 4dr tub). BTW he run's a Ford 6 with a prototype cross flow cylinder head in one of the 27 T's built by Batten.

Here is a manifold he is building for his car.
http://www.metalmeet.com/photopost/data/3204/46intake-manifold-med.jpg

[rkilgore29]

Thanks Ralph,

I have seen some of Greg's work on the old site. This work was new to me. He does very nice work. I hope to have that sort of time in the years to come. I seem to recall that Greg is retired and appears to be busy and enjoying it. :D

Interesting intake manifold work. That brings back some memories. We used to do a lot of this type of work before plastics moved in and began to dominate. Rapid prototype techniques using plastics have all but completely taken over prototype intake manifold fabrication. I originally went to work at Batten's to learn that very thing. I have built quite a few through the years.

[rkilgore29]

Hi John,

A while back you asked that I post some pictures of hammerforms I have used. Here are a couple of patterns that were to be hammerforms for some innercooler tanks and as the order quantity grew, became patterns for kirksite hammerforms.

http://www.metalmeet.com/photopost/data/3357/1915icooler_tank_pat_ose_side-thumb.JPG

http://www.metalmeet.com/photopost/data/3357/1915icooler_tank_pat_ose_top-thumb.JPG

http://www.metalmeet.com/photopost/data/3357/1915icooler_tank_pattern_ctr_-thumb.JPG

http://www.metalmeet.com/photopost/data/3357/1915icooler_tank_pat_ctr_ev-thumb.JPG

They were made from some plywood we had lying around, I am not sure what type. BTW plywood is not one of your better woods for carving. Some length was added by the patternmakers and they used a little filler to eliminate any reverse drafts. The kirksite parts have long since been recycled.

The tanks were being made from .090" 5052- H32 aluminum. I used this because I would be welding mounting plates to the tanks later and I wanted something durable. 3003 forms easier, but doesn't seem to work harden as well and is more susceptable to tears around mounting bosses or plates. Conventional wisdom is to use straps to mount tanks whenever possible and this was one of those times that straps were not an option.

[Boogiemanz1]

Rick, those are some neat shapes, and may have been tough to make, even with the hammerform. Thanks for sharing!......john

[chardy]

:) Hello Downriver Rick: I used to live East side Detroit,so of course Wyandotte is down river.I live in Hillsdale now, so still upriver,but different rivers and all smaller.I have mentioned Allied Products in my posts to Ralph, Allied used to do prototype panels for the car industry. It had a kirksite foundary,I am looking for some kirksite;20 lbs? do you have access to the stuff? I wish I had grabbed some poundage for my government jobs. If you do; I would like to buy that amount or alittle more, any help would be appreciated.

Thanks: Dick Stack

[rkilgore29]

Hi Dick,

I don't have any on hand. It has been a while since I have had any. We usually were required to return the material to the foundry after we were finished with the project, they kept our moulds and would repour if needed.

I can ask around and see if anyone I know has any.

Hillsdale is not that far away. Perhaps our paths will cross in the near future.

[chardy]

:( Boy, I sure would like to find some Kirksite, Ralph do you know anybody hoarding Kirksite?If anyone could come up with some at a reasonable price and nearby. I would reward them with a boiled muskrat dinner at the Erie Mi. VFW,or maybe not!I am getting more interested about the K stuff,it could be the answer to small volume production items. It has all kind of hand hammering possibilities, it will take a pretty good beating and keep its shape,with careful hammer work you could hold a corner and even some edges. Also faced with a filled epoxy.it could be hit pretty hard and often. Anybody have source for scrap/salvage metals-Zinc alloys? I do know it can be bought from Allcraft Silversmith Supply;small amounts and abit pricey; used to make silver/Gold flatware;molds and then hammered to a true from.I do hope this thread keeps on a goooing!!

Thanks: Dick Stack

[ralph]

Dick,
Haven't seen much in the way of kirksite dies in several years. They kind of went the way of wood models when cad die design and forming element analysis eliminated the need for binder development and soft tool proveout. I'm sure you saw that at Allied. Used to see one occasionally in the new model development shops when they would work on a "special".

I had seen some info several years ago about epoxy surfaces applied to steel build ups. The were being used both as hammer bucks and with mating dies in hydraulic presses for forming. Production runs were short at 500 or so, but the surface could be rebuilt and the buildups reused.

Several members here have posted their wireform bucks. They use heavily built up area as a hammerform for certain details. I watched Wray using his fender buck that way and Randy Ferguson has some posted pictures of the front front edge of his aluminum fender that he used as a hammerform for the tight returns in that area.
http://www.metalmeet.com/photopost/data/3126/11Imp_nose_assembly_side_view-med.jpg

Check out Randy's album for more ideas
http://www.metalmeet.com/photopost/showgallery.php?cat=3126

[chardy]

:) :D Hello Ralph and Rick and all KIrksite lovers or maybe just some interest in it.I did find some sources and users,in Michigan even! The Dearborn Deuce from Oakley Ind. in Clinton twp. uses kirksite for their short productions panels ;2000 or so. there are foundrys in Inkster and Roseville doing Kirksite.I know there could some good forms made and used for metal shaping projects. One source was selling it for $5 a lb, not bad for reusable material . On Google there was even ideas on metal filled epoxy for kirksite faces. I hope to find and use some; to do a hammering project! Hope the thread gets people thinking. Inspiration and persperation,start new projects and finish others.
Dick Stack