Views: 0 Author: Site Editor Publish Time: 2026-08-13 Origin: Site
You have found a potential sheet metal manufacturer.
You are ready to ask for a quotation.
Then the supplier replies:
Do you have a drawing?
What material do you need?
What thickness?
What quantity?
What finish?
Now the quotation process stops and starts again.
For custom sheet metal enclosures, this is common. A manufacturer cannot provide an accurate quotation if important requirements are missing.
The good news is that you do not need a perfect engineering package before contacting a manufacturer.
You simply need enough information for the supplier to understand what you want to make and what level of manufacturing support you need.
This guide gives you a practical RFQ checklist.
Before sending drawings, explain the product application.
For example:
EV charger enclosure
Outdoor charging station cabinet
IP65 LED display cabinet
Industrial equipment enclosure
Electrical control enclosure
Energy storage enclosure
This matters because the application can affect the quotation.
For example, an enclosure used indoors may have very different requirements from one installed outdoors.
An outdoor product may require consideration of:
Water protection
Corrosion resistance
Mounting method
Door sealing
Surface durability
You do not need to write a long product specification.
Even one sentence helps:
This enclosure will be used for an outdoor EV charging station and requires IP65 protection.
Or:
This is an IP65 LED display cabinet for outdoor installation.
That immediately gives the manufacturer useful context.
A 3D CAD file is usually the most useful starting point for a custom enclosure quotation.
Common formats may include:
STEP
STP
IGES
X_T
A 3D file helps the manufacturer understand:
Overall structure
Part geometry
Bending features
Assembly relationships
Internal mounting structures
It can also reduce the number of questions required before the project is reviewed.
But what if you do not have one?
You can still request a quotation.
Many product developers do not have complete production drawings at the first stage.
You may have:
A PDF drawing
A hand sketch
Product dimensions
A product rendering
Reference images
A physical sample
A rough product concept
These can still help start the discussion.
For example, a useful message could be:
We are developing a wall-mounted EV charger. The approximate enclosure size is 600 × 400 × 200 mm. We need front display and connector openings. Please review whether you can support the enclosure structure and provide guidance on the information needed for quotation.
This is much more useful than simply writing:
Please quote this product.
You do not need to solve every engineering detail before contacting a manufacturer.
The important thing is to clearly explain what stage your project is in.
If you have a drawing, include the key dimensions.
If you do not have a complete drawing, provide approximate dimensions.
For example:
Width: 600 mm
Height: 400 mm
Depth: 200 mm
Also explain whether the dimensions are:
Final confirmed dimensions
Approximate dimensions
Available space limitations
This is important.
Sometimes the external enclosure dimensions can still be adjusted, but the internal components have fixed dimensions.
For example:
The enclosure size can be adjusted, but the internal power module requires at least 450 mm of installation space.
That information may be more valuable to the manufacturer than a rough external dimension alone.
If your engineering team has already selected a material, include it in the RFQ.
For example:
Aluminum
Iron / carbon steel
Stainless steel
Galvanized steel
If you do not know the best material, say so.
For example:
We need a cost-effective material suitable for an outdoor EV charger enclosure. Please recommend an appropriate option.
This is better than guessing.
Material selection can affect:
Cost
Weight
Structural strength
Corrosion resistance
Surface finishing
A manufacturer can provide more useful feedback when they understand the product application.
Do not simply write:
Use thick steel.
If possible, specify:
Material: Iron
Thickness: 1.5 mm
If thickness has not been finalized, explain the product requirement instead.
For example:
The enclosure needs to support internal components weighing approximately 25 kg.
This gives useful information for structural evaluation.
Thickness affects both:
Product performance
Manufacturing cost
The goal is not necessarily to use the thickest material.
It is to use a suitable structure for the actual application.
This is one of the most commonly overlooked RFQ details.
A custom enclosure may require openings for:
Displays
Buttons
Indicator lights
Connectors
Cable entry
Fans
Switches
Locks
Mounting hardware
If the positions are important, provide dimensions or a drawing.
A quotation based only on the external box size may not reflect the actual manufacturing work required.
For example:
A 500 mm × 400 mm enclosure with no openings is very different from the same enclosure with:
One display cutout
Four connector openings
Eight button holes
Multiple ventilation areas
Cable entry features
External size alone does not describe the complete project.
This is another area where quotation misunderstandings happen.
Ask yourself:
What needs to be mounted inside the enclosure?
You may need:
Mounting plates
Brackets
Support frames
PCB mounting positions
Electrical component supports
Cable management features
If you have an internal layout, include it.
If you do not, provide:
Component dimensions
Component weight
Approximate installation positions
A supplier may quote only the outer enclosure if the internal structures are not clearly included in the RFQ.
Before comparing quotations, always confirm:
Does the price include the complete enclosure structure?
If protection is important, include it clearly.
For example:
EV charger enclosure: IP54 required.
Or:
EV charger enclosure: IP65 required.
For LED display cabinet projects, MT Metal focuses on:
IP65 waterproof LED display cabinets.
Protection requirements should be confirmed at the beginning because they can affect structural details such as:
Panel connections
Door structure
Sealing positions
Cable entry areas
Access openings
Do not assume that writing:
Outdoor enclosure
automatically communicates all protection requirements.
Surface finishing is not just a color decision.
Your RFQ may include requirements such as:
Powder coating
Color requirements
Surface appearance
Corrosion protection requirements
If you have a specific color requirement, provide it.
If you do not, you can simply state:
Black powder-coated finish.
The supplier can then confirm what additional information is required.
Always include the expected quantity.
For example:
Prototype: 1–5 units
Initial order: 50 units
Estimated annual demand: 2,000 units
You may not know the final production quantity yet.
That is normal.
Simply explain the current stage.
For example:
We are currently developing a prototype and expect production quantities after product validation.
This helps the manufacturer understand whether you are requesting:
Prototype pricing
Small-batch pricing
Production pricing
If possible, ask for separate pricing by quantity.
For example:
Please quote for 10, 100, and 500 units.
This can help you understand how production volume affects unit cost.
Every buyer has different priorities.
Tell the supplier what matters most.
For example:
We are looking for a cost-effective solution for production quantities above 1,000 units.
Our prototype needs to be completed as quickly as possible.
Appearance consistency is important because this is a customer-facing product.
The product will be installed outdoors and waterproof performance is a key requirement.
This information helps the manufacturer understand how to evaluate the project.
Before requesting a custom sheet metal enclosure quotation, check whether you can provide:
What will the enclosure be used for?
3D CAD, 2D drawing, sketch, rendering, or sample.
Width × Height × Depth.
If already specified.
If already specified.
Displays, connectors, buttons, cable entries, and other cutouts.
Brackets, mounting plates, supports, and component positions.
For example, IP54 or IP65 where applicable.
Powder coating, color, and appearance requirements.
Prototype, initial order, and expected production volume.
You do not need every item finalized before contacting a manufacturer.
But the more clearly you define the project, the easier it is to receive a meaningful quotation.
You can copy and complete the following template when requesting a quotation:
Product Name:
Product Application:
Project Stage: Prototype / Small Batch / Mass Production
Drawing Available: Yes / No
File Type:
Overall Dimensions:
Material:
Sheet Thickness:
Internal Components / Mounting Requirements:
Required Openings:
Protection Requirement:
Surface Finish:
Color:
Quantity Required:
Expected Annual Volume:
Target Delivery Time:
Additional Requirements:
Do not wait until every detail is finalized.
If your project is still under development, explain that clearly.
For example:
We currently have the product concept and internal component dimensions but need support developing the sheet metal enclosure structure.
Or:
We have a 3D model, but the internal mounting brackets and access panel design have not been finalized.
This is especially relevant for ODM projects.
The important thing is for the manufacturer to understand:
What is already defined?
What still needs to be developed?
That allows the project discussion to begin from the correct point.
When you receive multiple quotations, do not compare only the final number.
Ask:
A lower quotation may simply include less.
Before choosing a supplier, confirm that you are comparing the same manufacturing scope.
The fastest way to get a useful custom sheet metal enclosure quotation is not necessarily to provide a perfect engineering package.
It is to clearly communicate:
What are you making?
What information is already available?
What requirements are critical?
What still needs engineering support?
This allows the manufacturer to understand the project before quoting.
If you already have a drawing, send it.
If you only have a product concept, dimensions, or reference images, provide those and explain what you need.
A good quotation process starts with clear information.
No. A 3D file is helpful, but you can also start with 2D drawings, sketches, dimensions, reference images, or product samples.
Yes. Explain which parts of the product are already defined and which parts still require development or engineering support.
Material, thickness, overall size, structural complexity, openings, internal structures, surface finishing, protection requirements, and quantity can all affect pricing.
Yes. Even an estimated quantity helps the manufacturer understand whether the project is a prototype, small batch, or production project.
Yes. Requesting prices for several quantities can help you compare how the unit cost changes at different production volumes.
Send us your drawing, CAD file, product dimensions, or even an early product concept.
If some requirements are still under development, tell us what you already have and what support you need.
MT Metal can review your project requirements and help you clarify the manufacturing scope before quotation.
