Fire investigation unit

[Firebuilder]

The mold for the entire trumpeter eagle grill came out terrible.  I am not sure where I went wrong with it, but the modeling clay I used  to pack out some areas, stuck to  the silicone. So I cut the light bezels free from the grill , and will attempt to make a new mold for just the bezels. Hopefully my second attempt will go better.   I cut out the openings for the light assemblies and the grill.  After some more research on this cab, I noticed they make several different grills for their apparatus. I went with  one that was not to hard to build out of evergreen stock.  I just need to find some scale grill mesh now.
 

[hct728(Bob)]

So nice to see continuous progress on the scratchbuild! Sure there are setbacks but they are leading to big improvements in quality, my compliments to your persistence. 

l like your efforts at the grille, it may take a few tries but the unique shape is a great detail on this one

It's gonna be stunning!

[GLMFAA1]

I need some information:

greg

[Firebuilder]

Thanks Bob, much appreciated.

[Firebuilder]

Greg,

That is a SSB resin E450 ambulance. It was listed as a 2005. It took me about 18 months to find it on  eBay. They  don’t show up there to often and I lost a few bids, But finally found one with a buy now option .  It is a work in  progress duplicating  a rig for someone I know.  The cab is older  than what they have now, being it’s a 2019 model, but this was the best I could  for an E450 right now ,  I am contemplating building the box from scratch, originally I was going to modify the resin box that came with the kit, however after roughly marking it out, I have to change  just about everything on there, including the roof line to match the existing rig.

Dom

[GLMFAA1]

Thanks for the info. I'll stick to chopping my Coca-Cola van apart.

greg

[Chariots of Fire]

The front of the Ferarra is coming right along.  A word of caution, however.  Be sure and sand down the face of the cab and fill in all of the little crevasses in the corners before you install the light bezels.  The same with the grill.  I'm assuming you will do the latter after the painting is done.  Be sure to clean up the primer, patch any areas that are not smooth and if there is any glue spillover, get rid of it now.  The finish will be so much better if you do.  (talking from experience!?)   

Be sure and refine the grill as well.  Sand smooth, prime, sand again, fill in little areas, sand and prime again to see how it looks.

The light bezels are just right!  Lookin' good!

[Firebuilder]

Charlie,

I do plan on following your advice,  the top left corner of the cab curve  separated from the front panel when I was cutting the  hole for the bezel. So I had to re glue  and putty it. While I  had the putty out I filled a bunch of the imperfections you are talking about. The grill is filled and being sanded again  to. Then a wet sanding and on to primer finally. Then as you said more sanding and priming.  Here are pictures at the 2nd attempt making a mold for the bezels. It was  easier to make without the grill attached and came out much better than the first total failure.  I used a different clay to pack out  the back side of the bezel, and not as much clay  as I did with the first  mold.  I have to pour the 2nd part of the mold,  any suggestions before I do?  The Alumilite instructions are not clear on what to do before pouring the 2nd half. 

Dom

[1st 700 Quad]

On 1/16/2024 at 12:23 PM, Firebuilder said:

I have no idea yet on the windshield, I  read your build thread and see you made a buck , and then vacu formed. I  can make  the buck, but not sure if I should do it in a one piece or  two piece windshield. I don’t’  have anything to vacu form with,  and I still have to research how to do that at home if possible and what would be needed.  I did see a vacu forming machine on micro mark, but it’s a big investment for maybe just a few windshields, and I am not sure that is what would work for this . If I make the buck out of a block of wood, would it be to  much grain? I  found some Ren on a website and was thinking of ordering it and using that if it would be smoother. I also saw how you used that to  make your grill, which is something  else I have to tackle. I did make the mold for the trumpeter grill and lights, just waiting for the hobby shop to get in the resin. Once that is cast, i will cut the bezels free from the grill. I hope  mold I made came out ok, it’s the first attempt at  making a mold and casting a part.  For now  I am going to wet sand the cab, ending up with 3000 grit and then Get a coat of primer on and see what needs touch up.

Dom

Dom, I bought an old Mattel Vac-U-Form on eBay for $9.95 in working condition. The size would be big enough for a two-piece windshield.

[Chariots of Fire]

Hi, Dom.  The buck needs to be as smooth as possible.  I had difficulties getting the windshield pleces to stay clear until I glued on a piece of brass sheet and then polished it.  That seemed to do the trick for the clear stock.  The plastic to use is called PETG and is 0.020" thick.  

[Firebuilder]

Steven,

Thank you for the information, I will check out eBay and see what I can find. It may be a solution to the windshield problem.

Dom

[Firebuilder]

Charlie,

Thank again for  your guidance, I have the wood bucks made up, just need to pick up the brass  at the hobby shop. I   Will let you know how. It comes out  once completed.

[Firebuilder]

Finally got some primer on the cab, will leave it  alone for a few days and then sand it and prime again. Started  building the bumper.  Work on the chassis needs to get done  while waiting for primer to dry.

[Chariots of Fire]

In reply to your question about the second half of the mold.  Don't forget to coat the entire first part of the mold and master with mold release or you won't be able to separate the two parts.  You will have to build a dam around the first part also to contain the second part of the mold rubber.  You might want to wait until you get your new materials for the mold and casting resin.

[Scott Eriksen]

On 1/18/2024 at 1:36 PM, Firebuilder said:

Greg,

That is a SSB resin E450 ambulance. It was listed as a 2005. It took me about 18 months to find it on  eBay. They  don’t show up there to often and I lost a few bids, But finally found one with a buy now option .  It is a work in  progress duplicating  a rig for someone I know.  The cab is older  than what they have now, being it’s a 2019 model, but this was the best I could  for an E450 right now ,  I am contemplating building the box from scratch, originally I was going to modify the resin box that came with the kit, however after roughly marking it out, I have to change  just about everything on there, including the roof line to match the existing rig.

Dom

That looks like a Wheel Coach style grille on that rig .,,,,,,,,,, I retired from VCI Emergency Vehicles (Horton) back last July,,my son works there also,,they just got the FDNY contract back ? 

[GLMFAA1]

That grille is similar to a Wheeled Coach. Probably a Johnny Lightning Coke van as donor mold master. Don't know of WC putting deck plate on roof it seems it would make it even more top heavy than they were.

greg

[Firebuilder]

Charlie,

 I learned that  the hard way when I made the first mold and had to cut the  bezels out when the mold halves became one solid piece.  The second   Attempt ,The mold worked  but  the results are not to promising for the bezels.  I don’t know if I need to put less clay , or try to do it in a one piece mold. I am open to suggestions anyone has  for molding the bezels. I did make a mold for some seats I will need and was very satisfied with the results.

Dom

[Firebuilder]

15 hours ago, Scott Eriksen said:

That looks like a Wheel Coach style grille on that rig .,,,,,,,,,, I retired from VCI Emergency Vehicles (Horton) back last July,,my son works there also,,they just got the FDNY contract back ? 

Scott and Greg,

after doing a little research, this kit is modeled after an approximate 1990 to 1999 wheeled coach ambulance. I did not find any roof pictures for the diamond plate.  I do know that SSB was pretty accurate with most of the details though so it may have been there. Through out my career(now retired)  in the fire/ems service, I have been in  and driven many Horton/ VCI rigs and many other brands as well.

Dom

[Chariots of Fire]

Hey, Dom.  I'll do a little study of the bezels and see what I can come up with for a solution.

[Firebuilder]

20 hours ago, Chariots of Fire said:

Hey, Dom.  I'll do a little study of the bezels and see what I can come up with for a solution.

Thank you, as always your help  and guidance is greatly appreciated.

[Firebuilder]

Some work on the  AMT pumper chassis has been started. I am using Moebius rims and tires .  After building many of the AMT pumper kits, I started to replace the plastic front axel shafts with metal tubing and rod. I had way too many wheels break off  because of the weak plastic axel shaft. I also replaced the rear axel with  heavier rod.  The original rims and axel are much thinner, The Moebius rims have a wider axel  hole  which needs the heavier axle.  Started to mock up how the cab and box will sit on the chassis.

[Chariots of Fire]

 

Looks like real progress, Dom.  Here is a How To on making a mold for your headlights.  I'm doing one for the Pierce but the same procedure will work for you with one exception which I will explain.

HOW TO FOR MAKING A TWO PIECE MOLD

Begin by mounting the piece to be cast on a mound of clay.  In this case the headlight bezel includes a marker light that wraps around the curve of of the cab so it cannot be just mounted on a base.  Doing so would lock it into the mold.  Trim the clay so that it fits around the master.  In the case of the headlight bezel for the Ferrara you have to do one thing first.  Cut some masking tape and place the pieces over the back side of each lens opening.  Trim the tape so that it is at least flush with the sides with no overlap.  You want to be able to remove it later in the process.  AFTER the tape is in place mount the headlight master similar to what I have done here.

Here's another look at the bezel I'm doing.  You don't have to glue the clay down.  Just make sure there are no gaps between it and the base and that there are no gaps around the master.

Build the mold sides.  To do this I use foam board and a glue gun.  In my case as well as yours only tack the sides at the corners.  The reason for this will come later on.  A little mold material leaking out around the joints of the box is ok.

Mix up your mold material and prepare to pour it into the mold box.

Fill the box right to the top.  If you make the box higher, use your judgement as to how much to pour in.  No sense in wasting costly material but you want enough to be sure that the mold will not distort when you begin doing the actual casting.

After the mold sets (24 hours is a good time) use your Xacto knife and cut away the BOTTOM of the mold box.  This is why you need to tack glue the corners only.  It makes it easier to get the bottom away from the rest of the box.  In the photo below the bottom has been removed showing the bottom of the clay base that the headlight bezel is mounted on.  This clay needs to be removed now.  In your case after the clay is removed, remove the masking tape from the master.  Now comes the rest of the process.

In the photo above the clay has been removed and additional foam board has been cut into pieces and glued to the sides of the box. If you look at the end of the mold box you will see a notch cut in the rubber that is already set.  There is a similar notch on the other end.  These notches will align the top and bottom sections of the finished mold so that the casting will be not be off center.   Remember that the box is still upside down.  And here is the next very important step.  SPRAY OR PAINT THE ENTIRE INTERIOR OF THE BOX INCLUDING THE MASTER WITH MOLD RELEASE AGENT.  DO IT ONCE, LET IT SET FOR A WHILE AND THEN DO IT AGAIN.  BE SURE IT COVERS ALL EXPOSED SURFACES INSIDE THE BOX.

Mix up another batch of mold material and pour it into the box.  Make sure that the first material fills in every little area of the master.  The mold release will keep the new rubber from attaching to the older part of the mold.  Use a spatula or other implement to make sure the mold rubber fills all of the spaces including the notches.  Pour the rest of the mold rubber into the mold and let it sit for another 24 hours.   Next?  Pulling the mold apart and making the first casting.

 

 

Edited January 29, 2024 by Chariots of Fire

[hct728(Bob)]

Looking like something now it's in primer and on wheels! Good match between the two elements, and neat work on the bumper too

[Chariots of Fire]

The mold for the headlight bezels has been completed and below is a follow up with the first couple of castings done.  The first photo shows the mold with the upper half removed and with the original bottom half still in place.  By gluing just the corners of the upper box it was easy to remove.

And here is the completed mold with the lower box removed as well.  The separation is obvious.  With the mold release keeping the two halfs separate, they came apart easily.

In the photo below the master is still in the lower half but can be taken out.

The master is now out of the mold and casting can begin.

As with the mold making part of the process, two part casting resin was mixed in small cups with a mark on each one where Parts A and B will be filled to.   Below is the mold that has been filled with the mixed resin.  It turns white upon curing.  It is important to clear any bubbles from the mixture when it gets poured or they will show up in the final casting.  That is what happened to the first one I did.  But the nice thing is another one can be made.

Here's the second pour.  The cup to the rear had part B .  The cup in the foreground has parts A and B mixed together.  The fill lines are visible on each cup.  The two parts need to be thoroughly mixed until the apparent streaking clears up.  Then it can be poured into the mold as was done here.  The resin has not yet begun to cure in the mold.

Below is the second casting as it came out of the mold.  The tiny amount of flash is easily scraped away with an Xacto knife and fine sandpaper.  The one in the clamp is the first casting that I painted up with some Molotow chrome just to see how it will look.  Thus, endeth the lesson!?

 

[GLMFAA1]

Lesson from the master. Fantastic!

greg