follow boards and Ram-up blocks

In the past I have promised a follow board Tutorial
follow boards have two principle applications : mold irregular parting lines & to support a fragile pattern

here is a follow board sized for 12X12 flasks so it is 14X15 this follow board is designed so I can cast up to 4 saddles at one time. Saddles are the parts I make for mugs to create a flat surface for the mounting of accoutrements, saddles size and shape vary some based on what will be mounted on them, in this example we are making saddles for 1.75 inch coins and 2 inch shield shapes we are making (2) of each that is why 4 patterns are picterd, additionally the well and runner are rammed up with the follow board, this can be pinned loosely to hold it in place on the follow board , I prefer it loose , gates could also be included if your follow board was for a specific pattern, but the well, runner and gates cannot be permanently attached to the follow board

here is everything assembled and ready to ram up . a little note 3 of the patterns are metal (brass) one is the original carved wood I measured the wood pattern, at it's center it is 1/16 of an inch thick, the rear of these saddles are the arc of a 3 inch diameter circle so they mount on the mugs, they are also slightly thicker at the upper side so they are flat on the tapered side of a mug, the follow board replicates this ( Just note these patterns are tiney and technically too thin to cast, the seconfd function of the follow board is definately in use here

hereis the drag side as rammed note the patterns and runner assembly stay in place , but you are done with the follow board

now becasue this follow board is used with several patterns , I have to touch up the drag , note I have removed some sand and smooved alot of the surface this assures us the patterns will come out clean

if you where using loose patterns and coping down, this is the result you would have hoped for and probably spent 15 minutes at least getting, I have about 2 into this operation

Parting compound added

the sprue and the cope flask half in place and ready to Ram

the rammed cope: I cut the pouring well with the sprue cutter in place (limites sand falling into the sprue), it is pictured here with parting dust applied and brushed out with a soft camel hair brush and gently blown out ( this step is really important , more next)

this is the entire mold flipped ! this is known as the"double roll" what this does is put the large hanging sand sectiones of the cope face down ( gravity is holding them in place ) , my careful cleaning of the sprue and pouring well are important because if you roll the mold and a large chunk of sand falls onto the board and you set the mold on it it could crack the cope


I have lifted the Drag off the Cope 3 of the patterns are still on the cope with no loose sand I wish all 4where there, because that is a perfect result. remember earlier I said 3 of the patterns where brass and one wood ( think about that!)

there is that wooden pattern in the drag, a light tap and a bast of air and it popped right out, the runner and well are removed with a screw ( in the finished casting you will see I did a PP job of pulling the runner

I forgot to take a picture of the finished mold all that had to be done is cut the ingates and blow it out , ingates can go in the cope or drag, cope is prefered in most cases, because this pattern the cope is a critical surface, I normally gate the drag, in this case I gated the cope and drag, Now on the closing of the mold, if there is any chance of the hanging sand on the cope section falling, the drag has to be placed on the cope and the entire mold rolled again, having worked with this excellent piece MANY times I know that is seldome required unless I make a soft ram or one of the patterns shifts alot requirein alot of coping out

Here is the as ast piece, see all the flash and drops? Nope, the only drop is on the end of my splash well from my above mentioned poor pull. can anyone see the advantage of a good follow board the castings are perfect , they will be cut lightly sanded and buffed out. this is a perfect example and application of the follow board

BTW the Ram-up block works similarly to the follow board, but is a loose piece , old school often made of plaster

V/r HT1

 

just so you realize how tiny these patterns are this is the originall wood pattern, the one that stayed in the drag

here is the other pattern reversed on the casting


V/r HT1

 

I've got four followers made from EXP styrofoam.
They save so much time instead of coping down.
Was told they wouldn't last but they are hanging tough.
I even took a split pattern, glued it back together and made a follower.
Love those things.

 

Another follow board example.

I was out at thje foundry briefly (power outage shortened thge visit) thhis morning and pulled out the flask, pattern and follow board I intend to pour in a day or two. For scale the pattern is just over 36" long and about 7 inches high. I've cast this pattern probably 30 times or more.

The empty board

Pattern in the board as it would be rammed up


Another view


The board is really a board---plywood, MDF, and lumber amalgam.

The pattern is Baltic birch plywood.

Denis

 

Looks like the way we used to do loose piece with an offset parting. We typically molded the matchplate shape into it and just made a matchplate. We never ran loose piece tooling in production.

 

Hmmm, I think what I showed is actually properly termed a follow board as it is in place only for ramming up the cope to establish a part line, then it is removed and the drag is rammed.

Here is the definition I follow for loose piece: "Loose piece of a pattern which is attached to the pattern during molding, remains in the mold during lift-off and is only then removed separately. It is used for undercuts if the mold joint cannot be positioned in this cross section." Loose pieces are part of the pattern and are in place whilethe cope and drag are rammed, then the pattern is drawn and the loose pieces are drawn also either befroe or usually after the main pattern piece is drawn.

The above may or may not be exactly correct. I'll stand by for corrections.

Denis

 

We refer to anything that is not mounted to a plate as being loose piece....whether it be the whole casting or just a piece used to make an offset parting. I guess because of the many different types of patterns we used to have we had to differentiate between matchplates and nonmatchplate patterns of the same casting. It was just easier to say the loose piece or the matchplate when reffering to a pattern.

 

I guess the important thing is that people understand each other when using terms. Foundry work is so limited nowadays that various foundries can become pretty isolated and, no doubt develop terms and phrases unique to their shop. That’s all good. In the general use of “follow board” and “loose piece” there are useful distinctions to be made, though. In general use loose piece and follow board have distinct meanings.

Here is a good video showing the use of loose pieces (and really cool pattern making!):

Here is a follow board or block in use

The two images below were taken from this reference: http://www.atlasfdry.com/glossaryf.htm




Denis

 

Nothing like having new supervisors from north of the mason dixon line come in and have no idea what language we are speaking here. I have been in contact with hundreds of different folks from the industry and each one has their own version of what certain defects or equipment is called. Try going to schools with people from all over the country and have a conversation....the first few minutes is just trying to figure out what the hell they are talking about. We have terms no-one else uses...especially in defects....know what a rat is? Bird's eye? rat is a sticker or metallic projection..sand stuck on the pattern that looks like a rat or mouse in low lighting conditions ... bird's eye is a motion defect that occurs when the mold get pushed or bumped during the solidification of a vertical mold and resembles a bird's eye. I get to play translator when I go to schools with some of our people now because I have already been a few times and learned the language. LOL Casting defects school is the worse....they have a list of about ten different names for each defect so everybody will know what defect they are talking about. AFS and CMI are both good about trying to create a universal language.

 

Billy, north of the M-D line we usually like to cite references for what we are saying as opposed to claiming personal authority, especially if questioned.

I put up my references that seem to suggest the Yankee language spoken may not be in the category of “no idea.” I’d be more convinced with a couple references.

Denis

 

LOL... We have two guys from Wisconsin...not too far from each other....worked at different foundries...cant have a conversation with them at the same time without them citing a reference about who is correct and who is not....gets pretty funny some times. I will start some conversation I know will get them going and then leave.
They have several foundry dictionaries available...I will stick with what gets the point across the fastest....dont have time for the peeing contest.

 

Common term that I am almost positive no-one uses anywhere but here...bull. A pouring ladle attached to a trolley that can carry couple hundred pounds of iron. Got its name because the handles looked like bull horns...grab the bull by the horns and get to pouring.LOL We had many other types of ladles so we had to give them specific nicknames for people to know which is which. The latest language barrier is from my newest supervisor who calls short pours...poured shorts. Each time he says that he gets questioned as to why he says it that way.LOL Same thing I reckon...just a little different way of saying it.

 

I know...I get a weird visual every time he says that!

 

Thanks for that Dennis, I was having difficulty understanding what a Follow Board did, but after seeing your photos, the penny dropped

 

Denis

Good, Jim. Since posting above I’ve looked at quite a few web references to follow boards (can be called cradle boards) and loose pieces. They are all consistent in saying that follow boards are not pattern pieces but are a device for establishing a parting line whereas loose pieces are pattern pieces used in situations like the lamppost video where backdraft would prevent drawing a solid pattern.

One interesting idea that came up that I had not heard of previously that sounds useful was the suggestion to use linseed oil-bound core sand to make a follow board. Just place the loose pattern in a flask. Ram it up with core sand. Part down to the parting line. Remove the pattern and cure the sand. Voila! Follow board quickly made. That was from a 1940’s Modern Shop Practice book.. Nowadays silicate or epoxy binder might also be used.

Denis