Let's talk about flattening chips (1 Viewer)

[superchromix]

Hi,

Before you say it, I know there are other threads about chip flattening. The point of this thread will make itself clear, hopefully.

All of the commonly used chip flattening techniques are based on some variation of the "clamp" method - that is, put a barrel of warped chips in a clamp (possibly using ceramic blanks as spacers), tighten the clamp, and add heat. Wait for some time, re-tighten the clamp, remove the clamp from heat and allow to cool.

While this method is tried and tested, and no doubt works with some degree of success, it seems to have serious limitations. First of all, it's SLOW. The max number of chips that you can do at a time is one or two barrels, and the heating and cooling time also seems long. On top of that, it is very hard to control the parameters of the system, namely each person will tighten the clamp differently, and the chips will reach a different temperature depending on the particular oven or heating pad you are using, all depending on the air circulation around the chips because the chips are not actually in contact with anything which is thermally conductive.

HENCE, I am asking myself if there is a better way. A flattening method which would give reproducible results, and have a high enough throughput to flatten say 1000 chips in a couple of hours. Can it be done?

IF I know any group of people who are resourceful and goal driven, it's the chippers on this site. I'm sure it can be done. I even have an idea of how to do it. So, if you're interested, tell me what you think of this idea.

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CONCEPT: Chip flattening device.

Working principle: Gravity.

Description: 1. Flat metal baseplate with circular recesses, each of which have a depth of ~ 1/2 a chip thickness. Places for 25 or 50 chips. 2. Flat metal top plate of matching size.

Operation: 1. Heat base plate and top plate in oven or on heat pad until a certain temperature is reached. 2. Place warped chips in circular recesses. 3. Place heavy metal top plate on top of chips. 4. Wait a certain period of time while chips are flattened by pressure of top plate, while absorbing heat from the two plates. 5. Remove chips.

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What I like about the concept:

-- Gravity is doing the work - the force on the chips will always be the same, just the weight of the top plate. No variation due to how tight you tightened the clamp.

-- The heat can be controlled precisely. The thermal mass of the top plate and the base plate together are much larger than anything else in the system. Once they are heated to a certain temperature, the heat that is transferred to the chips during flattening will be constant, irrespective of how you are doing the heating (oven, heating pad, etc). You would just need a thermometer for this.

-- The design could be stacked, for doing larger numbers of chips. Imagine a system where four sets of plates are stacked on top of each other, each with 25 chips. You could run 100 chips at a time.

-- Once designed, the CAD drawings could be uploaded to an online CNC company and anyone could order the identical parts, anywhere in the world.

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Open questions:

1. How much weight / heat / time ? How heavy would the top and base plates need to be to be used effectively? Experimentation is needed to determine this.

2. Cost of the CNC milled parts. In principle, the design is very simple, and could be made from machined Aluminum or Brass. I doubt this would cost that much from an online CNC but I could be wrong.

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So, could this be a new way of flattening chips? I think the idea has merits. Change my mind

 

[Forty4]

Don’t think I’m understanding correctly.

There are only two plates for the entire contraption? Or are you talking about making a mold style where the two combine to make it the perfect thickness of the chip? I think the first which begs the question how is the heat going to transfer from the top and bottom chips to the middle chips? How will the weight of the chips on top not affect the chips on the bottom, and compress them more?

 

[Goldfish]

My chip flattening station is in my office next to my desk so time is not really a factor......I flatten while I work.....note the creative use of the wooden vice grips.....

 

[superchromix]

What I’m thinking is the depth of the recess in the bottom plate accommodates only one chip, so each chip is in contact with the top and bottom plate.

To build a stacked system, one could avoid extra pressure on the chips in the lower levels if stacked bottom plates are supported by e.g. rods at the four corners. I would have to draw this to explain the idea fully.

 

[FordPickup92]

@Ben8257 ?

 

[superchromix]

My chip flattening station is in my office next to my desk so time is not really a factor......I flatten while I work.....note the creative use of the wooden vice grips.....
View attachment 643729

I see that you’ve got the clamp process down to a system, but I’m just brainstorming for something different.

A set of plates that I could just throw in the oven and forget about until they equilibrate to a certain temperature, then add the chips, leave them in the plates for 10 min, flip them out onto a table to cool, and presto 100 chips done.

 

[davislane]

wont the outside temperature also be a variable?

 

[Ben8257]

I am not sure that enough pressure would be applied or equally transferred to all chips. Some say light pressure in clamps. I use ceramics between but also clamp pretty hard. Seems like if you don't use a lot of pressure the clay doesn't move much if at all, too much pressure and over heating can push the hats back into the clay, but I still use quite a bit of pressure and I am not sure that you would achieve that by a metal plate and a weight on top, also if we are talking thick metal I would think that would slow the cooling process and potentially lead to over exposure and again possibly damage the chips.

My though is most ovens you can fit 4 clamps and that's 80plus chips. We work on chips everyday so that's just normal life for Brie and I. I get the concept and interested, but ai would start woth low value chips. The over exposure factor here is seriously a concern. When you take a clamp out of the oven those chips begin cooling quickly, you could easily be adding 5 plus minutes to the cooking time with this procedure.

Following along foe sure!!

 

[Colquhoun]

One thing to realize is that the heat is softening the chip and the clamp is flattening it...but the process doesn’t end there. It must be cooled while under the pressure as well.
The internal stress that causes the chip to warp in the first place is relaxed by the heat. The clamping brings it to the desired shape, and he cooling “sets” this shape in the chip, and reduces that inner “stress” to find another shape.
I use the heating pad, but I’ve never heated AFTER clamping. I place chips into a folded heating pad, after 10 minutes they’re toasty warm...then gently clamp them up. Remove when cool.
If I really wanted to do more than a few barrels at a time, the easiest solution is more heating pads and clamps.

 

[Shaggy]

A challenge that is noted in the other threads is that not all chips "like" the same temperature or duration. I think the key is understanding what is going on within the chip when it is being flattened. As @Colquhoun points out, you are effectively removing the internal stresses of the chip while its in a new shape/form.

I think the prevailing theory for what causes a chip to warp is heat... usually from the hotstamping operation. This heat causes stress within the chip and it tacos to relax. When we clamp the chip we put those stresses back in... when we heat the chip while clamped, we relax the stresses again. It is important to heat the chip above a certain temperature to "restructure the grains." This temperature has to get to the center of the chip (envision cooking a roast).

In order to get the center to the right temperature... quickly, you could apply a lot of heat to the face of the chip... but that will melt/deform the face. The best method would be a highly controlled, long heat, not exceeding the desired temperature... Sous Vide anyone?

The clamping pressure really isn't that important... just enough to flatten the chip... the temperature and fully heating the chip is the magic.

Additionally... who has 1000 chips that are warped? The worst I have had was ~1000 hotstamped Lakeshore fracs where about 10% of them were warped.

 

[Ben8257]

If you use the light trick (hold a barrel of chips up to a light and move up and down. Looking for light between the chips) I would say that close to 50% of the chips we have bought have been warped even AS $20 IHCs

Probably the worst come from hot desert climates, I never would have believed there were 05 CDIs with warping issues. But sure enough my first batch from Texas were pretty bad. Probably the worst I have seen were these

Took me almost and month to get them back to resonable and some were not salvageable.

Definitely worse with hotstamps, if they are old school fracs from the desert, they are likely warped. I believe it is far more common than people think. Want to check, put a barrel of chips on a hard counter top and touch the edge of the top chip, if there is any wobble at all they are warped. I have probably flattened a few thousand chips at this point.

 

[Taghkanic]

A hand-cranked book/paper press might be modified for this purpose. Not sure the plates themselves necessarily need to be heated. These can be found on Etsy (search for antique book press) in cast iron or wood. Might just warm the chips some other way, then use the press (slowwwwly).

 

[Taghkanic]

There are also high-tech temperature-controlled rosin presses with metal plates. Don’t ask how I know this.

 

[allforcharity]

There are also high-tech temperature-controlled rosin presses with metal plates. Don’t ask how I know this.

How do you know this, Sam?

 

[BamaT8ter]

This heat causes stress within the chip and it tacos to relax.

Sometimes I taco to relax too.

 

[navels]

Man who doesn't