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silencer bump stop

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Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Patrick, if you end up getting it printed, make sure you specify a flexible filament. Other wise it will be a solid plastic part. Don't let them make it using PLA or PETG. Interesting to see what they. They'll have to create the 3D model and the STL file, not sure what that will cost you.
Hopefully you can make the commercial one work.

BT

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Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Just 3D printed this bumper. Based only on dimensions from the previous posts. Over-all length is 1.75, Designed for a 5/8" hole. Major diameter is 1-1/4. Printed in black polyurethane. 95A durometer so it is firm. I don't know the durometer of the OEM bumper. Printed it hollow with 3/16 walls but I'm going to re-print one with 3/32 walls. That will make it a bit softer.

Only other part I've been asked to print for any TR7-8 is the shift boot grommet.

Now I may have to get a TR8 to see if it fits.

BT



Edited 1 time(s). Last edit at 2019-02-14 09:49 AM by Bpt70gt.


Attachments:
TR8 Exhaust Bumper-1.JPG    31.9 KB
TR8 Exhaust Bumper-1.JPG

TR8 Exhaust Bumper-2.JPG    29.4 KB
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TR8 Exhaust Bumper-4.JPG    30.2 KB
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TR7 shift boot insert.JPG    19.5 KB
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Pat.L Avatar
Pat.L Silver Member Patrick Ledford
New Wilmington, PA, USA   USA
I ordered a universal bump stop from Energy Suspensions Parts part number 9.951. I did not know they came in pairs, the cost was $14.00 and change with shipping.

First picture is of the original bump stop off my TR8. It came out quite easily as someone had cut a vertical slice off the top to make insertion easier. It has the measurements showing dimensions.

The second picture shows the differences. Overall width is not a problem as there is plenty of room. The length is 1/8 inch shorter which also should not be a problem. The long stem indicated by the letter C will be removed as it is for a pull in insertion. The location B is 1/16 smaller than the hole in the frame but the location A is larger than the hole on the frame by 1/8 inch.

My thought is to apply Permatex adhesive and gasket sealer to the B location to help hold the Bump stop in place. The universal Bump Stop is slightly harder than the original but the old rubber one may have softened with age. But I believe there is a enough give to not damage the muffler. I may use my heat gun to see how much heat the universal ones can withstand as they will sit above a muffler.



Patrick
1980 TR8 DHC TPVDV8AT209637
1957 TR-3 Under restoration TS20462LO
Western Pennsylvania Triumph Association
TWOA

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Attachments:
Bump_stop_original_measurements.jpg    24.5 KB
Bump_stop_original_measurements.jpg

Bump_stop_New_markings.jpg    26.9 KB
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Pat.L Avatar
Pat.L Silver Member Patrick Ledford
New Wilmington, PA, USA   USA
In reply to # 1596473 by Bpt70gt Just 3D printed this bumper. Based only on dimensions from the previous posts. Over-all length is 1.75, Designed for a 5/8" hole. Major diameter is 1-1/4. Printed in black polyurethane. 95A durometer so it is firm. I don't know the durometer of the OEM bumper. Printed it hollow with 3/16 walls but I'm going to re-print one with 3/32 walls. That will make it a bit softer.

Only other part I've been asked to print for any TR7-8 is the shift boot grommet.

Now I may have to get a TR8 to see if it fits.

BT

Brian: I did not know you were going to print these. Are you selling them and the gear box shifter bushing?



Patrick
1980 TR8 DHC TPVDV8AT209637
1957 TR-3 Under restoration TS20462LO
Western Pennsylvania Triumph Association
TWOA

Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Hi Pat, Well, I generally make parts for the TR250/6 or GT6 because those are the two cars I have. I do sell a few parts for those cars. I try to concentrate on NLA parts. I was surfing the TR7/8 site and saw you inquiring about this bumper. Generally I need an actual part to reverse engineer something but you and others posted enough dimension to get me started. Your last post filled in the rest of the blanks. Mainly the thickness of the frame member (1/8"winking smiley although that seems a bit thick for a frame. Certainly different than my TR250 frame. I'm always a bit skeptical about measurements taken with a scale. I'm a retired machinist and too used to working in thousands of an inch I guess. I have version two of the bumper on the printer this minute--thinner wall section. I always like to test my creations but can't do that in this case since I don't have a TR8. I could easily drill a hole in a piece of sheet metal if I new the thickness and accurate diameter of the hole in the frame. That way I could test the bumper for fit. Since the demand for this bumper is so small, 3D printing works better because it is best suited for small quantities. It's just a part on an STL file and can be printed on demand. It may not be the least expensive way to produce parts but the cost can be reasonable if the part doesn't exist anymore. Trying to get a mold made can easily cost a couple grand for the engineering and machining a mold. Not an in-expensive route to take. Then it would take a run of several hundred to get the price point down to something we could afford.

I printed the shift boot grommet because a person saw that I printed custom parts. He had a TR6 and needed a NLA part for his hardtop. Then he asked if I could print the shift boot grommet. He provided enough info so I could create a 3D model and then printed that. Even though that grommet is available from one other source (to my knowledge), in this case I could print it at a better cost. It's made in PETG plastic or I can do nylon also.

Back to the Bumper, attached is another possible version, I could make it so it screws into the frame.

Yes, I do sell parts if I feel they are good enough, it's a hobby and not a business. It helps keep my hobby going.

BT


Attachments:
TR8 Exhaust Bumper thread in style.JPG    14.6 KB
TR8 Exhaust Bumper thread in style.JPG

Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Here is the bumper with the size adjusted to Pats dimensions. Yes, can be printed in red also.grinning smiley

BT


Attachments:
TR8 exhaust bumper-actual size-1.JPG    12.7 KB
TR8 exhaust bumper-actual size-1.JPG

TR8 exhaust bumper-actual size-2.JPG    14.8 KB
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Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, OR, USA   USA
1980 Triumph TR7 Drophead "The Great Pumpkin"
1980 Triumph TR8 "Wedgie"
In reply to # 1596522 by Bpt70gt Here is the bumper with the size adjusted to Pats dimensions. Yes, can be printed in red also.grinning smiley

BT

Brian:

Another TR7 part that is unobtanium is the pair of straps that support the glove box door on the TR7. The originals were identical in length, despite the fact that the center to center distances for the mounting points were not identical. Part ZKC99 in the attached JPEG.

I requested that the TWOA club 3D print some of these and the shift boot bushing as they are not available, but no go so far. I think black nylon would work just fine. Alas, no drawings at this time, so it will sit on the shelf as an idea.

Very pretty work on your part, and a potential cottage industry.

Vance



1980 Platinum Metallic TR8, frame off restoration, complete.
1980 Vermilion TR7 Sprint replica, in progress.


Attachments:
Glovebox.JPG    43.4 KB
Glovebox.JPG

Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Vance, the shift boot insert is an item I've printed for another forum member a while back. He provided the dimensions so I just created the 3D model on CAD and then let my printer do it's work. Can't tell you how much I enjoy watching the part grow up on a glass bed. This will be the future to help keep our cars in parts where our regular suppliers don't want make something unless they can sell hundreds of them. The boot inserts I make, I print them in PETG, still very strong. The best (strongest) filament I can print with my machine is nylon alloy 910 but it's super strong nylon and is over kill for this simple insert. PETG is what soda and water bottles are made from. So it is strong but with a bit of flexibility depending on how thick the part is.

The TR7 glove box strap would be a good candidate for TPU (thermoplastic polyurethane). Pretty strong but quite flexible. To create this strap, I'd need one to take measurements from or a good sketch with full dimensions.

I'm always looking for NLA items to re-create. Up to this point I've limited myself to TR6, TR250, GT6, Spitfire parts. Only because I'm familiar with those cars since my first TR3 back in 1967. I have a list of 20 or so parts for those cars that I've created. During the winter it's too cold up here in New England to work on my cars so it's my "creative" season. If someone can provide me with a sample strap or a good sketch, I'll see what I can do.

Interestingly, Porsche and Mercedes have created a small catalog of printed parts for their older classics. Porsche has a whopping 9 parts so far, ironically I have twice that. I've shipped parts to France, England(just last week), and next week an order going to Australia. All parts that are NLA up to now. I'm getting a kick out of this. It's just a hobby but I like the challenge.

Pretty cool that your club has 3D printer capability. The printing usually is the easy part, creating the CAD 3D model can be the time consuming task.

BT


Attachments:
TR7 shift boot insert--the family.JPG    30.3 KB
TR7 shift boot insert--the family.JPG

Xseries Brian Ridley-Jones
WATERLOOVILLE, Hampshire, UK   GBR
Vance,
I went to a couple of plastic parts factories to redo ZKC99 (I have a pair of NOS to use as a pattern) - but the pattern alone was going to cost around $2500 so I would have either had to charge $100 each or make a huge loss. I have tried to find a place to have some printed - but no luck so far!
I have found a local company that would remake the exhaust bumpers (minimum 50 - but that is just 25 TR8s!) but the printed version would seem to be a better bet as the quantity produced would match orders.
I can provide images of NOS ZKC99 if required (and most parts for a TR8 efi) though as with the GEX7490 bump stop I am loathe to open a sealed packet just for a photograph rather than potential production.
Brian RJ England

Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Vance, attached CAD rendering of the ZKC99 strap. I'd print the ends in Black nylon and use polyurethane cord between the two ends. Just an idea if there is a need. Again, just guessing on the dimensions of the ends. Very little information on this strap.

The 4th prototype of the GEX7490 exhaust bumper is on the printer now. I've got the dimensions dialed in now thanks to LaVerne. Now I'm experimenting with the density (cushion) ability of the polyurethane.

BT


Attachments:
TR8-7_ZKC99Strap.JPG    10.5 KB
TR8-7_ZKC99Strap.JPG

Pat.L Avatar
Pat.L Silver Member Patrick Ledford
New Wilmington, PA, USA   USA
In reply to # 1596864 by Bpt70gt Vance, attached CAD rendering of the ZKC99 strap. I'd print the ends in Black nylon and use polyurethane cord between the two ends. Just an idea if there is a need. Again, just guessing on the dimensions of the ends. Very little information on this strap.

The 4th prototype of the GEX7490 exhaust bumper is on the printer now. I've got the dimensions dialed in now thanks to LaVerne. Now I'm experimenting with the density (cushion) ability of the polyurethane.

BT

Brian:

Sending a PM



Patrick
1980 TR8 DHC TPVDV8AT209637
1957 TR-3 Under restoration TS20462LO
Western Pennsylvania Triumph Association
TWOA

Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Here is prototype #4. As usual it takes several attempts to get the best combination of design and methods but this one is close. True to size as dimensions supplied by members of the forum. Again, material is polyurethane so it is firm but this model is hollow with 1/8" walls. I had printed one with 1/16 walls but that was too soft. I'll print one more and this time with 3/32" walls and that may be the best combination of the two. I can't imagine this bumper coming into play to often unless you are hitting speed bumps at 40mph so I suspect it sits in the TR frame and takes only an occasional hit from the muffler.

On the ZKC99 strap, that's about as far as I can go until someone can provide accurate dimensions for the ends. Of course it all depends if there is a need for this part also.

BT


Attachments:
TR8GEX7470-2.JPG    31.7 KB
TR8GEX7470-2.JPG

TR8GEX7470-3.JPG    32.2 KB
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TR8GEX7470-4.JPG    34.6 KB
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Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Bumper update: After a lot of prototypes, I think this bumper is very close to a done project. Just some final testing to accomplish for proper fit into the frame.

BT


Attachments:
GEX7470_REV12-1.JPG    20.5 KB
GEX7470_REV12-1.JPG

TR8GEX7470_Rev12-2.JPG    16.8 KB
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