BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
After study of the 3D road wheels, I determined they could be made to use ball bearings inside, whether by design or luck, I do not know. They seemed to have been designed to hold a flanged Ball bearing on each sides, of the following size; 3mm interior hole, 2.5mm wide and 7mm high. Therefore, 24 of them are needed, they are available from China for a few dollars for a lot of 10. This also means an inexpensive Flat head Lock Cotter Clevis M3 Pin can be used as shaft, also from China. No ball bearing with M4 center could fit the road wheel so this is why M3 is the best alternative.
After the head of the pin has been filed a bit, the provided 3D hub caps fit perfectly on the road wheel..
These are the parts required for the suspension arm. I previously made the shaft hole of the arm 4mm wide. This is perfect for a 4mm aluminum tube to be inserted inside, into which the M3 (3x16mm) shaft will enter for a tight fit.
After the 4mm aluminum tube is pressed inside the arm, a hole is made for a M1.8 metal bolt to lock the whole thing in place. The bolt will run through the hole in the 3mm shaft pin.
The road wheel is installed on the suspension arm, and is very solid and runs on ball bearings... What more can be asked.
To install the suspension arms on the hull, it seemed logical to somehow use the hole that is drilled at a specific location. Not sure if it was planned but there is enough room for a (6mm interior size) washer to be inserted in the slot in the plasticard, which happens to be correctly located in front of the hole, then a bolt can be used as a retaining device against the washer. Again, the hole for the bolt was not standard so I drilled it to fit a standard M3 screw.
Torsions bars are connected to the arms.
The two prototypes work perfectly and the suspension is really solid and smooth, it runs on Leopard 2 bars. I thinned them a bit to make them more flexible. Great, now I have 10 more to do in similar fashion and the suspension will be finished. There are likely many ways to do the suspension, this is one of them and it seems to work well and use inexpensive items.
Regards, Louis
After the head of the pin has been filed a bit, the provided 3D hub caps fit perfectly on the road wheel..
These are the parts required for the suspension arm. I previously made the shaft hole of the arm 4mm wide. This is perfect for a 4mm aluminum tube to be inserted inside, into which the M3 (3x16mm) shaft will enter for a tight fit.
After the 4mm aluminum tube is pressed inside the arm, a hole is made for a M1.8 metal bolt to lock the whole thing in place. The bolt will run through the hole in the 3mm shaft pin.
The road wheel is installed on the suspension arm, and is very solid and runs on ball bearings... What more can be asked.
To install the suspension arms on the hull, it seemed logical to somehow use the hole that is drilled at a specific location. Not sure if it was planned but there is enough room for a (6mm interior size) washer to be inserted in the slot in the plasticard, which happens to be correctly located in front of the hole, then a bolt can be used as a retaining device against the washer. Again, the hole for the bolt was not standard so I drilled it to fit a standard M3 screw.
Torsions bars are connected to the arms.
The two prototypes work perfectly and the suspension is really solid and smooth, it runs on Leopard 2 bars. I thinned them a bit to make them more flexible. Great, now I have 10 more to do in similar fashion and the suspension will be finished. There are likely many ways to do the suspension, this is one of them and it seems to work well and use inexpensive items.
Regards, Louis
Last edited by lmcq11 on Thu Nov 15, 2018 3:28 am, edited 4 times in total.
- c.rainford73
- Major
- Posts: 6104
- Joined: Thu Aug 25, 2016 7:34 pm
- Location: Connecticut USA
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Wow great progress Louis I'm really enjoying this already!
Tanks alot....
- midlife306
- Warrant Officer 1st Class
- Posts: 2238
- Joined: Sun Aug 27, 2017 10:34 am
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Coming on really well Louis
A tip for you for improving the surface finish of 3D parts, try a steel wire brush, I find they reduce the sanding needed dramatically.
Cheers
Wayne
Sent from my iPhone using Tapatalk
A tip for you for improving the surface finish of 3D parts, try a steel wire brush, I find they reduce the sanding needed dramatically.
Cheers
Wayne
Sent from my iPhone using Tapatalk
- HERMAN BIX
- Brigadier
- Posts: 10318
- Joined: Sun Jan 12, 2014 12:15 am
- Location: Gold Coast,Australia
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Ingenious solution Sir.
A pin from China !! and Leopard suspension arms
Of course you knew it would work
Top job that man
A pin from China !! and Leopard suspension arms
Of course you knew it would work
Top job that man
HL JAGDPANTHER,HL TIGER 1,HL PzIII MUNITIONSCHLEPPER, HL KT OCTOPUS,HL PANTHER ZU-FUSS,HL STuG III,HL T34/85 BEDSPRING,
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Ah Man, thank you for you encouragements. There is no doubt in my mind that I can make this a good looking BMP-1 but this build is really difficult. The bruises on my hands can testify. Every step is a creative challenge followed by a bigger one.
The twelves road wheels are attached to their suspension.
After some research on the interior compartment, I noticed that the BMP has no raised floor and the suspension shows and is part of the deck. Therefore, I need to take care of the esthetic aspect of the suspension because whatever I do, it will show.
Suspension is installed. Once the gearbox is put on, I will have to adjust the suspension to make sure the chassis is horizontal and everything is strait. Those torsion bars provide good strength.
View of suspension arrangement.
The lower hull is being assembled. You can see that the gearbox will be way at the front with the first road wheel supporting the brunt of it. It will need its shock absorber to be stable.
At this point, the upper hull needs to be figured out and built as a separate module that fits on top of the lower hull. Its not obvious.
Need to install the Idler adjuster before the rear panel is put on because it will reduce room to maneuvers.
In preparation for the installation of the gearbox, I need to figure out the front shock absorber, in a way that will provide additional suspension support to the front of the vehicle. The front is quite long and will likely need to contain some electronics as well.
Regards, Louis
The twelves road wheels are attached to their suspension.
After some research on the interior compartment, I noticed that the BMP has no raised floor and the suspension shows and is part of the deck. Therefore, I need to take care of the esthetic aspect of the suspension because whatever I do, it will show.
Suspension is installed. Once the gearbox is put on, I will have to adjust the suspension to make sure the chassis is horizontal and everything is strait. Those torsion bars provide good strength.
View of suspension arrangement.
The lower hull is being assembled. You can see that the gearbox will be way at the front with the first road wheel supporting the brunt of it. It will need its shock absorber to be stable.
At this point, the upper hull needs to be figured out and built as a separate module that fits on top of the lower hull. Its not obvious.
Need to install the Idler adjuster before the rear panel is put on because it will reduce room to maneuvers.
In preparation for the installation of the gearbox, I need to figure out the front shock absorber, in a way that will provide additional suspension support to the front of the vehicle. The front is quite long and will likely need to contain some electronics as well.
Regards, Louis
- HERMAN BIX
- Brigadier
- Posts: 10318
- Joined: Sun Jan 12, 2014 12:15 am
- Location: Gold Coast,Australia
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
I will try to find a picture, but could an H/L PzIII lead arm work with its shock absorber that has capacity for an extra spring inside it ?
Its not a torsion bar, but might be able to work a different way to carry more load.
Its not a torsion bar, but might be able to work a different way to carry more load.
HL JAGDPANTHER,HL TIGER 1,HL PzIII MUNITIONSCHLEPPER, HL KT OCTOPUS,HL PANTHER ZU-FUSS,HL STuG III,HL T34/85 BEDSPRING,
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
HL PZIV MALTA,MATORRO JAGDTIGER,HL F05 TIGER,TAMIYA KT,HL PANTHERDOZER,HL EARLY PANTHER G,TAIGEN/RAMINATOR T34/76,
HL AN-BRI-RAM SU-85
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Thanks Herman, yeah, two of the provided arms by Christian have the attachment for a shock absorber, they were installed at the front. The plan is to put PzIII shock absorbers on them.HERMAN BIX wrote:could an H/L PzIII lead arm work with its shock absorber that has capacity for an extra spring
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Hi,
On such build, the modeller like myself is left with his own resources to move forward, hoping for the best. Complaining will not get me anywhere, finding solutions do, while improving skills at the same time. The builder must have the right mind set to get into this stuff. I can see this is not for everyone.
This BMP-1 build is particularly interesting in the sense that every single assembly had a surprise and required some level of problem resolution.
Continuing with the hull
The PzIII shock absorber is refined and the spring is shortened. Updated version on the right.
With the front shock absorbers installed, I am no longer worried about the ability for the suspension to carry the weight of the gearbox and electronics at the front.
I had purchased a cheap Mato Tiger Idler adjuster from Mato Mart with the hope of using it for the BMP. However, after some study, I determined the design is not adaptable for modifications that would allow a good looking interior. I therefore have to select a more expensive HennTec Panther idler adjuster like I usually use. Its on order.
Starting the upper hull. The top needs to be made removable like any RC tank. To facilitate the assembly and placement of the upper hull parts on the lower hull, small drops of superglue are used to keep the parts in place where they connect with the lower hull. These temporary joints will be easily snapped once the structure of upper hull is fully built, strait and solid.
A PzIII gearbox is installed strait on the bottom beams, sockets for the screws were made with plasticard at specific locations, avoiding any contact with the torsion bars.
Some reinforcements are required during the assembly to ensure every part is strait.
The 3D printed top is partially sanded at first. Then I applied a layer of putty all over it which is then sanded in the hope of having a smooth surface. Honestly, I would have preferred a set of plasticard parts to assemble. It is not strait and needs a metal reinforcement strip under to make it flat.
Bummer! the top is too narrow and it does not reach the hull sides... I re-checked that everything around was properly assembled. I see nothing wrong with the previous assembly and the angles of the side armor plates fit the Trumpeter kit. It looks like a design flaw. From the couple of pictures available on the Ludwigs website, I can see that the design of the lower hull has changed at one point because it is not like mine. Pictures show 2 variations. I can only guess what went wrong.
When one side is put on top of its base, the other side is missing 5mm to reach its base.
I do not want to change the angles of the side armor, therefore the top needs to be extended somehow. I installed a 5mm wide brass strip on both sides to create a bridge. With putty and some adjustment of the ventilation holes, it should be ok.
Continuing on following post
On such build, the modeller like myself is left with his own resources to move forward, hoping for the best. Complaining will not get me anywhere, finding solutions do, while improving skills at the same time. The builder must have the right mind set to get into this stuff. I can see this is not for everyone.
This BMP-1 build is particularly interesting in the sense that every single assembly had a surprise and required some level of problem resolution.
Continuing with the hull
The PzIII shock absorber is refined and the spring is shortened. Updated version on the right.
With the front shock absorbers installed, I am no longer worried about the ability for the suspension to carry the weight of the gearbox and electronics at the front.
I had purchased a cheap Mato Tiger Idler adjuster from Mato Mart with the hope of using it for the BMP. However, after some study, I determined the design is not adaptable for modifications that would allow a good looking interior. I therefore have to select a more expensive HennTec Panther idler adjuster like I usually use. Its on order.
Starting the upper hull. The top needs to be made removable like any RC tank. To facilitate the assembly and placement of the upper hull parts on the lower hull, small drops of superglue are used to keep the parts in place where they connect with the lower hull. These temporary joints will be easily snapped once the structure of upper hull is fully built, strait and solid.
A PzIII gearbox is installed strait on the bottom beams, sockets for the screws were made with plasticard at specific locations, avoiding any contact with the torsion bars.
Some reinforcements are required during the assembly to ensure every part is strait.
The 3D printed top is partially sanded at first. Then I applied a layer of putty all over it which is then sanded in the hope of having a smooth surface. Honestly, I would have preferred a set of plasticard parts to assemble. It is not strait and needs a metal reinforcement strip under to make it flat.
Bummer! the top is too narrow and it does not reach the hull sides... I re-checked that everything around was properly assembled. I see nothing wrong with the previous assembly and the angles of the side armor plates fit the Trumpeter kit. It looks like a design flaw. From the couple of pictures available on the Ludwigs website, I can see that the design of the lower hull has changed at one point because it is not like mine. Pictures show 2 variations. I can only guess what went wrong.
When one side is put on top of its base, the other side is missing 5mm to reach its base.
I do not want to change the angles of the side armor, therefore the top needs to be extended somehow. I installed a 5mm wide brass strip on both sides to create a bridge. With putty and some adjustment of the ventilation holes, it should be ok.
Continuing on following post
Last edited by lmcq11 on Sat Nov 17, 2018 3:20 pm, edited 2 times in total.
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
The brass strip are glued in the slots underneath the top.
Putty is applied over the brass extension to recreate the angles and then sanded. It looks good. The top is glued in place and more putty applied at the joints, awaiting drying for sanding. No worries, once sanded, more putty and more sanding, it will be all smooth. The 3D printed top was too high compared to the front section so I had to reduce the height of the hull sides by at least 2mm.
Dry fitting of the upper hull parts at the back show more issues. I am seeing that their lenght are too short by a few mm in order to reach the back plate. All parts will need to be extended, no big deal. But I would really have preferred that they be too long than too short...
Current overall view of the model. This thing is pretty big. I will compare it to other models soon to show you.
Regards, Louis
Putty is applied over the brass extension to recreate the angles and then sanded. It looks good. The top is glued in place and more putty applied at the joints, awaiting drying for sanding. No worries, once sanded, more putty and more sanding, it will be all smooth. The 3D printed top was too high compared to the front section so I had to reduce the height of the hull sides by at least 2mm.
Dry fitting of the upper hull parts at the back show more issues. I am seeing that their lenght are too short by a few mm in order to reach the back plate. All parts will need to be extended, no big deal. But I would really have preferred that they be too long than too short...
Current overall view of the model. This thing is pretty big. I will compare it to other models soon to show you.
Regards, Louis
Re: BMP-1 IFV - Soviet army, Afghanistan 1980s - Build
Great work so far! It’s looking like a BMP now