Post by Southgate on Aug 20, 2008 16:09:17 GMT -5
Post #1
MCM Regular
Group: Members
Posts: 73
Joined: 13-March 06
From: Central Oregon
Member No.: 85
I posted this some time back, at another forum but it has been a while. There seems to be a lot more action here, so I thought some here might like to see it. I have edited it so that there are links to the various pictures instead of clogging up the thread with a dozen direct picture posts.
If anyone want's to make a working rear suspension on their AMT Paystar or any of the Ertl Internationals that have the Hendrickson rear tandem setup, follow along and I'll do my best to explain how I did it on my Paystar as posted earlier.
I actually assembled another one to take pics of the process.
You need to start with an unbuilt model, or at least be ready to do some serious dissassembling.
Tools you'll need are the usual assortment of Exacto knife, files solvent cement, Super glue, baking soda, razor saw, a 1/16 and 3/32 drill bit. and a jewelers saw if you can get one. They're great to have.
Also you will see I am using some brass pins or nails I got from a dollhouse supplier. Whatever pins you use, you need a drill bit of the same size. My pins are .024, so a .024 drill bit is a number 73.
You'll need some aluminum tubing in the following sizes: 1/16, 3/32, 1/8, 5/32. And a little bit of .020 styrene sheet or strip.
I start by cutting the rocker arms off the spring assembly casting. Note how far the sawblade cut goes here to the bottom of the "springs" on the inside of the piece.
img.photobucket.com/albums/v727/Sou...te/PB250149.jpg
The pieces should look like this at this point.
img.photobucket.com/albums/v727/Sou...te/PB240148.jpg
Cut off the the little nibs from the rocker arms and file the resulting piece flat across the top. Cement a piece of .020 styrene across the top. Put a slight bend in it to match that of the rocker arm. Set aside to dry.
img.photobucket.com/albums/v727/Sou...te/PB250151.jpg
Also as seen in above photo, clean up the spring casting with a file, and glue on the other side of the hanger from the kit, parts # 117 and 118 in the Paystar kit. Glue these very securely.
Assemble the kit's axles according to the instructions, but leave off the front brake controls, we'll get to those later. Make sure the parts of the axles where the little clips are in the photo above are securely cemented. I use Testors liquid solvent cement for this.
Now assemble the frame's crossmembers together, not to the frame but just the 2 halves and drill a hole the size of the pins you are using through the mounts where the traction bars will go. drill the holes as far away from the crossmember as you can but not too close to the outer edge. Do both sides.
img.photobucket.com/albums/v727/Sou...
Now get the traction bars, parts 123b, and file one of the round ends of each to a little smaller diameter than it is. This makes for better moving clearance when the parts move up and down.
Drill your pin size hole in the round ends, OFF CENTER, slightly towards the outer ends. This helps motion too.
img.photobucket.com/albums/v727/Sou...te/PB250154.jpg
![]()
img.photobucket.com/albums/v727/Southgate/PB250154.jpg[/IMG]
Now, back to the rocker arms. If you lay them on a flat surface with the added styrene strips facing UP, and slip a piece of 1/8' aluminum tubing through them and press down on it. you'll notice that the arms want to lean due to the shape of the cut plastic. Do note though that the arms are at least centered lengthwise.
Use some super glue to glue the 1/8 tube to the rocker arm, towards the bottom, away from the styrene strip. this keeps it centered lengthwise. You have to make sure that the rocker arm is square to the tubing, both vertically and horizontally. In other words a perfect "t" with about 1/2 to 1 inch sticking out both sides of the arms, and that the arms are level with the tube. At this point it is real fragile, but it allows to adjust until everything is square. Once it is SQUARE, start filling in the hole around the tube in the rocker arm with a drop of super glue and then bury it with baking soda. I found that putting the glue on the tube and letting it run into the joint worked well. Don't worry about how caked up the tubing gets. Just make sure the cavity in the rocker arm gets filled by repeating this process on both sides.
Don't let the superglue get on the detail of the rocker arm outside of that cavity.
img.photobucket.com/albums/v727/Sou...te/PB250158.jpg
When it's all filled in, let it dry a while or use accelerator.
Now cut the aluminum tubing off just outside the rocker arms. Cut off tube on both sides of each of the rocker arms
img.photobucket.com/albums/v727/Sou...te/PB250165.jpg
Now file the tubing down to where it is just flush with the rocker arms.
img.photobucket.com/albums/v727/Sou...te/PB250166.jpg
Now we're going to start assembling things together. NO GLUE!
Take a rocker arm and position it onto an axle where it mounts as per kit, and drill a pin sized hole through the outer part of the hanger into the rocker arm pivot. Keep everything as centered as you can.
img.photobucket.com/albums/v727/Sou...te/PB250169.jpg
I drilled the outer hole until the drill marked the arm pivot, then just drilled the arms' hole, and drilled the hanger all the way through the other side separately.
Now you need to remove the little locater nibs from the rocker arms, and carve out the little spot on the axles where they would have mounted. This gives room for plenty of motion. Put a pin through this assembly now, and it should look like this with space between the rocker arm and the axle
img.photobucket.com/albums/v727/Sou...te/PB250172.jpg
This should move freely.
Do the remaining 3 mounts this same way, but make sure that each joint goes together as you drilled it. If you were off center on one joint slightly more than others it won't matter cuz the holes will be off consistantly. In other words, these hinged joints aren't interchangable.
All four corners assembled:
img.photobucket.com/albums/v727/Sou...te/PB250173.jpg
Now with a 3/32 drill bit, from the outside, center the bit in the pivot of the rocker hanger and drill it out, and go through the other side too. I just twisted the bit in my fingers to keep things slow and in control. when you have this done, glue these to your truck's frame.
img.photobucket.com/albums/v727/Sou...te/PB250174.jpg
Now take your pin sized drill and drill through the mounts on the axles where the traction bars go. Keep these holes a little on the high side to make sure there's room for the traction bar's round ends in that mount.
Now for the fun part: When the frame is dry enough to be handled you can place the assembled rocker arms into their hangers, and take a piece of 3/32 tubing and insert it into one sice of the hangers, and twisting it in your fingers, work it through to the outside of the other hanger. Don't glue it, it will stay there fine, and allow the rockers to pivot freely. Cut it off flush.
At this time, get your traction bars and with fine needle nose pliers, work the pivot pins into the bar's mounts on the axle and through the ends of the traction bars, and do the same on the frame with that SMALL END going on the frame crossmember's bar mount. Thing should look like this:
img.photobucket.com/albums/v727/Sou...te/PB250175.jpg
Hmmm. I got my traction bars in backwards! Still works, but do try to have yours turned the other way, it can impede motion if not.
OK, I'm Back to make the drive lines work with this setup they have to be able to telescope and pivot with the works.
The first step is to drill a hole through the pivot of the u joint. I usually go half way through and then got to the other side and drill to meet in the center.
img.photobucket.com/albums/v727/Sou...te/PB250182.jpg
Now is where you need a jewlers saw. Cut around the u joint yoke, making sure you go past the hole you drilled.
img.photobucket.com/albums/v727/Sou...te/PB250184.jpg
Resulting pieces:
img.photobucket.com/albums/v727/Sou...te/PB250186.jpg
Pin 'em:
img.photobucket.com/albums/v727/Sou...te/PB250187.jpg
Cut up the drive shaft like this. Note how much of the shaft is left on the u joints.
img.photobucket.com/albums/v727/Sou...te/PB250188.jpg
On the u joint with the thicker piece of shaft left on it drill a 1/16 hole in it deep enough to super glue in a short piece of 1/16 aluminum tubing about 1/4-3/8 long... And you'll need some 1/8 and 3/32 tubing as well
img.photobucket.com/albums/v727/Sou...te/PB250191.jpg
img.photobucket.com/albums/v727/Sou...te/PB250192.jpg
Cut a piece of 1/8 tubing and a piece of 3/32 each 5/8 inch long.
Super glue the 1/16 piece of tube into the hole ya drilled, and then glue the piece of 3/32 on over it. Glue the 1/8 tube on over the stub on the ither u joint. This is a loose fit, just so ya know.
When these are dry, you can slide them together. Look at that li'l bugger.
img.photobucket.com/albums/v727/Sou...te/PB250195.jpg
Make sure that the u joint pivots have lots of swing. If not you can pull the pins and file for more clearance in the yoke.
Now take the smaller shaft u Joint and glue it into the front axle's hole making sure that the arc of the pivot is in line with the hole on the aft axle. When it dries, slide the outer shaft onto it and make sure it is aligned properly too and glue it to the aft axle. Ta- Da!
Forward motion:
img.photobucket.com/albums/v727/Sou...te/PB250197.jpg
Rearward motion. note how the length of that little shaft changes.
img.photobucket.com/albums/v727/Sou...te/PB250200.jpg
Now for those brake parts: They hit the frame if left as they are when the front axle raises high enough so I cut the mount off, shortened and rounded it again and repositioned it onto the cylinder, and glue it on to the axle.
img.photobucket.com/albums/v727/Sou...te/PB250180.jpg
![]()
img.photobucket.com/albums/v727/Sou...te/PB250181.jpg
In the pictures above you can see that it now has clearance when the axle is at full raised height.
I didn't show the long front drive shaft detail, but it uses the same basic technique, except that the larger tube would be 5/32 and the smaller front part of the shaft, (inner) is 1/8.
A couple notes here. I started out with unpainted unassembled parts. They are black cuz they are from earlier issue Ertl trucks, molded in black plastic. A few pieces were missing so I stole 'em from a newer kit, thus white parts. The frame I put it on is from a Transtar 4200, which will account for some of the differences between Paystar and Transtar frames, but the procedure is the same. Later Transtar Eagle kits came with this suspension, as well as "S" series models, so there are a number of kits this procedure will work on.
When cutting aluminum tube, be sure to ream the inner edge of tubing something is gonna slide into, and slightly round the tube that will be used to slide into another tube or you can have issues with fit.
This may seem like a long process, but if you take it step at a time and work carefully, it isn't that hard. This is my 2nd one, so I hope I got all the bugs out before presenting it. Lets hear if it works for ya! Dan
MCM Regular
Group: Members
Posts: 73
Joined: 13-March 06
From: Central Oregon
Member No.: 85
I posted this some time back, at another forum but it has been a while. There seems to be a lot more action here, so I thought some here might like to see it. I have edited it so that there are links to the various pictures instead of clogging up the thread with a dozen direct picture posts.
If anyone want's to make a working rear suspension on their AMT Paystar or any of the Ertl Internationals that have the Hendrickson rear tandem setup, follow along and I'll do my best to explain how I did it on my Paystar as posted earlier.
I actually assembled another one to take pics of the process.
You need to start with an unbuilt model, or at least be ready to do some serious dissassembling.
Tools you'll need are the usual assortment of Exacto knife, files solvent cement, Super glue, baking soda, razor saw, a 1/16 and 3/32 drill bit. and a jewelers saw if you can get one. They're great to have.
Also you will see I am using some brass pins or nails I got from a dollhouse supplier. Whatever pins you use, you need a drill bit of the same size. My pins are .024, so a .024 drill bit is a number 73.
You'll need some aluminum tubing in the following sizes: 1/16, 3/32, 1/8, 5/32. And a little bit of .020 styrene sheet or strip.
I start by cutting the rocker arms off the spring assembly casting. Note how far the sawblade cut goes here to the bottom of the "springs" on the inside of the piece.
img.photobucket.com/albums/v727/Sou...te/PB250149.jpg
The pieces should look like this at this point.
img.photobucket.com/albums/v727/Sou...te/PB240148.jpg
Cut off the the little nibs from the rocker arms and file the resulting piece flat across the top. Cement a piece of .020 styrene across the top. Put a slight bend in it to match that of the rocker arm. Set aside to dry.
img.photobucket.com/albums/v727/Sou...te/PB250151.jpg
Also as seen in above photo, clean up the spring casting with a file, and glue on the other side of the hanger from the kit, parts # 117 and 118 in the Paystar kit. Glue these very securely.
Assemble the kit's axles according to the instructions, but leave off the front brake controls, we'll get to those later. Make sure the parts of the axles where the little clips are in the photo above are securely cemented. I use Testors liquid solvent cement for this.
Now assemble the frame's crossmembers together, not to the frame but just the 2 halves and drill a hole the size of the pins you are using through the mounts where the traction bars will go. drill the holes as far away from the crossmember as you can but not too close to the outer edge. Do both sides.
img.photobucket.com/albums/v727/Sou...
Now get the traction bars, parts 123b, and file one of the round ends of each to a little smaller diameter than it is. This makes for better moving clearance when the parts move up and down.
Drill your pin size hole in the round ends, OFF CENTER, slightly towards the outer ends. This helps motion too.
img.photobucket.com/albums/v727/Sou...te/PB250154.jpg
img.photobucket.com/albums/v727/Southgate/PB250154.jpg[/IMG]
Now, back to the rocker arms. If you lay them on a flat surface with the added styrene strips facing UP, and slip a piece of 1/8' aluminum tubing through them and press down on it. you'll notice that the arms want to lean due to the shape of the cut plastic. Do note though that the arms are at least centered lengthwise.
Use some super glue to glue the 1/8 tube to the rocker arm, towards the bottom, away from the styrene strip. this keeps it centered lengthwise. You have to make sure that the rocker arm is square to the tubing, both vertically and horizontally. In other words a perfect "t" with about 1/2 to 1 inch sticking out both sides of the arms, and that the arms are level with the tube. At this point it is real fragile, but it allows to adjust until everything is square. Once it is SQUARE, start filling in the hole around the tube in the rocker arm with a drop of super glue and then bury it with baking soda. I found that putting the glue on the tube and letting it run into the joint worked well. Don't worry about how caked up the tubing gets. Just make sure the cavity in the rocker arm gets filled by repeating this process on both sides.
Don't let the superglue get on the detail of the rocker arm outside of that cavity.
img.photobucket.com/albums/v727/Sou...te/PB250158.jpg
When it's all filled in, let it dry a while or use accelerator.
Now cut the aluminum tubing off just outside the rocker arms. Cut off tube on both sides of each of the rocker arms
img.photobucket.com/albums/v727/Sou...te/PB250165.jpg
Now file the tubing down to where it is just flush with the rocker arms.
img.photobucket.com/albums/v727/Sou...te/PB250166.jpg
Now we're going to start assembling things together. NO GLUE!
Take a rocker arm and position it onto an axle where it mounts as per kit, and drill a pin sized hole through the outer part of the hanger into the rocker arm pivot. Keep everything as centered as you can.
img.photobucket.com/albums/v727/Sou...te/PB250169.jpg
I drilled the outer hole until the drill marked the arm pivot, then just drilled the arms' hole, and drilled the hanger all the way through the other side separately.
Now you need to remove the little locater nibs from the rocker arms, and carve out the little spot on the axles where they would have mounted. This gives room for plenty of motion. Put a pin through this assembly now, and it should look like this with space between the rocker arm and the axle
img.photobucket.com/albums/v727/Sou...te/PB250172.jpg
This should move freely.
Do the remaining 3 mounts this same way, but make sure that each joint goes together as you drilled it. If you were off center on one joint slightly more than others it won't matter cuz the holes will be off consistantly. In other words, these hinged joints aren't interchangable.
All four corners assembled:
img.photobucket.com/albums/v727/Sou...te/PB250173.jpg
Now with a 3/32 drill bit, from the outside, center the bit in the pivot of the rocker hanger and drill it out, and go through the other side too. I just twisted the bit in my fingers to keep things slow and in control. when you have this done, glue these to your truck's frame.
img.photobucket.com/albums/v727/Sou...te/PB250174.jpg
Now take your pin sized drill and drill through the mounts on the axles where the traction bars go. Keep these holes a little on the high side to make sure there's room for the traction bar's round ends in that mount.
Now for the fun part: When the frame is dry enough to be handled you can place the assembled rocker arms into their hangers, and take a piece of 3/32 tubing and insert it into one sice of the hangers, and twisting it in your fingers, work it through to the outside of the other hanger. Don't glue it, it will stay there fine, and allow the rockers to pivot freely. Cut it off flush.
At this time, get your traction bars and with fine needle nose pliers, work the pivot pins into the bar's mounts on the axle and through the ends of the traction bars, and do the same on the frame with that SMALL END going on the frame crossmember's bar mount. Thing should look like this:
img.photobucket.com/albums/v727/Sou...te/PB250175.jpg
Hmmm. I got my traction bars in backwards! Still works, but do try to have yours turned the other way, it can impede motion if not.
OK, I'm Back to make the drive lines work with this setup they have to be able to telescope and pivot with the works.
The first step is to drill a hole through the pivot of the u joint. I usually go half way through and then got to the other side and drill to meet in the center.
img.photobucket.com/albums/v727/Sou...te/PB250182.jpg
Now is where you need a jewlers saw. Cut around the u joint yoke, making sure you go past the hole you drilled.
img.photobucket.com/albums/v727/Sou...te/PB250184.jpg
Resulting pieces:
img.photobucket.com/albums/v727/Sou...te/PB250186.jpg
Pin 'em:
img.photobucket.com/albums/v727/Sou...te/PB250187.jpg
Cut up the drive shaft like this. Note how much of the shaft is left on the u joints.
img.photobucket.com/albums/v727/Sou...te/PB250188.jpg
On the u joint with the thicker piece of shaft left on it drill a 1/16 hole in it deep enough to super glue in a short piece of 1/16 aluminum tubing about 1/4-3/8 long... And you'll need some 1/8 and 3/32 tubing as well
img.photobucket.com/albums/v727/Sou...te/PB250191.jpg
img.photobucket.com/albums/v727/Sou...te/PB250192.jpg
Cut a piece of 1/8 tubing and a piece of 3/32 each 5/8 inch long.
Super glue the 1/16 piece of tube into the hole ya drilled, and then glue the piece of 3/32 on over it. Glue the 1/8 tube on over the stub on the ither u joint. This is a loose fit, just so ya know.
When these are dry, you can slide them together. Look at that li'l bugger.
img.photobucket.com/albums/v727/Sou...te/PB250195.jpg
Make sure that the u joint pivots have lots of swing. If not you can pull the pins and file for more clearance in the yoke.
Now take the smaller shaft u Joint and glue it into the front axle's hole making sure that the arc of the pivot is in line with the hole on the aft axle. When it dries, slide the outer shaft onto it and make sure it is aligned properly too and glue it to the aft axle. Ta- Da!
Forward motion:
img.photobucket.com/albums/v727/Sou...te/PB250197.jpg
Rearward motion. note how the length of that little shaft changes.
img.photobucket.com/albums/v727/Sou...te/PB250200.jpg
Now for those brake parts: They hit the frame if left as they are when the front axle raises high enough so I cut the mount off, shortened and rounded it again and repositioned it onto the cylinder, and glue it on to the axle.
img.photobucket.com/albums/v727/Sou...te/PB250180.jpg
img.photobucket.com/albums/v727/Sou...te/PB250181.jpg
In the pictures above you can see that it now has clearance when the axle is at full raised height.
I didn't show the long front drive shaft detail, but it uses the same basic technique, except that the larger tube would be 5/32 and the smaller front part of the shaft, (inner) is 1/8.
A couple notes here. I started out with unpainted unassembled parts. They are black cuz they are from earlier issue Ertl trucks, molded in black plastic. A few pieces were missing so I stole 'em from a newer kit, thus white parts. The frame I put it on is from a Transtar 4200, which will account for some of the differences between Paystar and Transtar frames, but the procedure is the same. Later Transtar Eagle kits came with this suspension, as well as "S" series models, so there are a number of kits this procedure will work on.
When cutting aluminum tube, be sure to ream the inner edge of tubing something is gonna slide into, and slightly round the tube that will be used to slide into another tube or you can have issues with fit.
This may seem like a long process, but if you take it step at a time and work carefully, it isn't that hard. This is my 2nd one, so I hope I got all the bugs out before presenting it. Lets hear if it works for ya! Dan
Two freaks with the same idea 
I did it on my Astro. Not exactly the same way, but it still works like the same way.
